1
|
Kraft BD, Verhulst S, Lai TP, Sullenger BA, Wang Y, Rountree W, Chen L, Woods CW, Denny TN, Aviv A. T-cell count and T-cell telomere length in patients with severe COVID-19. Front Immunol 2024; 15:1356638. [PMID: 38550590 PMCID: PMC10972845 DOI: 10.3389/fimmu.2024.1356638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 02/19/2024] [Indexed: 04/02/2024] Open
Abstract
Lymphocyte telomere length (TL) is highly variable and shortens with age. Short telomeres may impede TL-dependent T-cell clonal expansion with viral infection. As SARS-CoV-2 infection can induce prolonged and severe T-cell lymphopenia, infected adults, and particularly older adults with short telomeres, may display severe T-cell lymphopenia. To examine the relationship between T-cell TL parameters and T-cell counts, we studied 40 patients hospitalized with severe COVID-19. T-cells were isolated from lymphocytes, counted using flow cytometry, and their TL parameters were measured using the Telomere Shortest Length Assay. The cohort (median age = 62 years, 27% female) was racially and ethnically diverse (33% White, 35% Black, and 33% Other). On intensive care unit study day 1, T-cell count (mean=1.03 x109/L) was inversely related to age (p=0.007) and higher in females than males (p=0.025). Mean TL was 3.88 kilobases (kb), and 45.3% of telomeres were shorter than 3 kb. Using multiple regression analysis and adjusting for age and sex, T-cell count decreased with increased proportion of T-cell telomeres shorter than 3 kb (p=0.033) and increased with mean TL (p=0.052). Our findings suggest an association between the buildup of short telomeres within T-cells and explain in part reduced peripheral blood T-cell counts in patients with severe COVID-19. Shortened T-cell telomeres may be a risk factor for COVID-19-associated T-cell lymphopenia.
Collapse
Affiliation(s)
- Bryan D. Kraft
- Division of Pulmonary, Allergy, and Critical Care Medicine, Duke University Medical Center, Durham, NC, United States
| | - Simon Verhulst
- Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, Netherlands
| | - Tsung-Po Lai
- Center of Human Development and Aging, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
| | - Bruce A. Sullenger
- Department of Surgery, Duke University Medical Center, Durham, NC, United States
| | - Yunfei Wang
- Duke Human Vaccine Institute, Durham, NC, United States
| | - Wes Rountree
- Duke Human Vaccine Institute, Durham, NC, United States
| | - Lingye Chen
- Division of Pulmonary, Allergy, and Critical Care Medicine, Duke University Medical Center, Durham, NC, United States
| | - Christopher W. Woods
- Center for Infectious Disease Diagnostics and Innovation, Duke University Medical Center, Durham, NC, United States
- Department of Medicine, Durham Veterans Affairs Health Care System, Durham, NC, United States
| | | | - Abraham Aviv
- Center of Human Development and Aging, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
- Department of Pediatrics, New Jersey Medical School, Rutgers, The State University of New Jersey, Newark, NJ, United States
| |
Collapse
|
2
|
Chen O, Jiang C, Berta T, Powell Gray B, Furutani K, Sullenger BA, Ji RR. MicroRNA let-7b enhances spinal cord nociceptive synaptic transmission and induces acute and persistent pain through neuronal and microglial signaling. Pain 2024:00006396-990000000-00548. [PMID: 38452223 DOI: 10.1097/j.pain.0000000000003206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 01/02/2024] [Indexed: 03/09/2024]
Abstract
ABSTRACT Secreted microRNAs (miRNAs) have been detected in various body fluids including the cerebrospinal fluid, yet their direct role in regulating synaptic transmission remains uncertain. We found that intrathecal injection of low dose of let-7b (1 μg) induced short-term (<24 hours) mechanical allodynia and heat hyperalgesia, a response that is compromised in Tlr7-/- or Trpa1-/- mice. Ex vivo and in vivo calcium imaging in GCaMP6-report mice revealed increased calcium signal in spinal cord afferent terminals and doral root ganglion/dorsal root ganglia neurons following spinal perfusion and intraplantar injection of let-7b. Patch-clamp recordings also demonstrated enhanced excitatory synaptic transmission (miniature excitatory postsynaptic currents [EPSCs]) in spinal nociceptive neurons following let-7b perfusion or optogenetic activation of axonal terminals. The elevation in spinal calcium signaling and EPSCs was dependent on the presence of toll-like receptor-7 (TLR7) and transient receptor potential ion channel subtype A1 (TRPA1). In addition, endogenous let-7b is enriched in spinal cord synaptosome, and peripheral inflammation increased let-7b in doral root ganglion/dorsal root ganglia neurons, spinal cord tissue, and the cerebrospinal fluid. Notably, let-7b antagomir inhibited inflammatory pain and inflammation-induced synaptic plasticity (EPSC increase), suggesting an endogenous role of let-7b in regulating pain and synaptic transmission. Furthermore, intrathecal injection of let-7b, at a higher dose (10 μg), induced persistent mechanical allodynia for >2 weeks, which was abolished in Tlr7-/- mice. The high dose of let-7b also induced microgliosis in the spinal cord. Of interest, intrathecal minocycline only inhibited let-7b-induced mechanical allodynia in male but not female mice. Our findings indicate that the secreted microRNA let-7b has the capacity to provoke pain through both neuronal and glial signaling, thereby establishing miRNA as an emerging neuromodulator.
Collapse
Affiliation(s)
- Ouyang Chen
- Department of Anesthesiology, Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC, United States
- Department of Cell Biology, Duke University Medical Center, Durham, NC, United States
| | - Changyu Jiang
- Department of Anesthesiology, Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC, United States
| | - Temugin Berta
- Department of Anesthesiology, Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC, United States
- Department of Anesthesiology, Pain Research Center, University of Cincinnati Medical Center, Cincinnati, OH, United States
| | - Bethany Powell Gray
- Department of Surgery, Duke Cancer Institute, Duke University Medical Center, Durham, NC, United States
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, United States
| | - Kenta Furutani
- Department of Anesthesiology, Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC, United States
| | - Bruce A Sullenger
- Department of Surgery, Duke Cancer Institute, Duke University Medical Center, Durham, NC, United States
| | - Ru-Rong Ji
- Department of Anesthesiology, Center for Translational Pain Medicine, Duke University Medical Center, Durham, NC, United States
- Department of Cell Biology, Duke University Medical Center, Durham, NC, United States
- Department of Neurobiology, Duke University Medical Center, Durham, NC, United States
| |
Collapse
|
3
|
Requena MD, Yan A, Llanga T, Sullenger BA. Reversible Aptamer Staining, Sorting, and Cleaning of Cells (Clean FACS) with Antidote Oligonucleotide or Nuclease Yields Fully Responsive Cells. Nucleic Acid Ther 2024; 34:12-17. [PMID: 38285522 DOI: 10.1089/nat.2023.0050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2024] Open
Abstract
The ability to reverse the binding of aptamers to their target proteins has received considerable attention for developing controllable therapeutic agents. Recently, use of aptamers as reversible cell-sorting ligands has also sparked interest. Antibodies are currently utilized for isolating cells expressing a particular cell surface receptor. The inability to remove antibodies from isolated cells following sorting greatly limits their utility for many applications. Previously, we described how a particular aptamer-antidote oligonucleotide pair can isolate cells and clean them. Here, we demonstrate that this approach is generalizable; aptamers can simultaneously recognize more than one cell type during fluorescent activated cell sorting (FACS). Moreover, we describe a novel approach to reverse aptamer binding following cell sorting using a nuclease. This alternative strategy represents a cleaning approach that does not require the generation of antidote oligonucleotides for each aptamer and will greatly reduce the cost and expand the utility of Clean FACS.
Collapse
Affiliation(s)
- Martin D Requena
- Department of Surgery, Duke University, Durham, North Carolina, USA
- University Program in Genetics and Genomics, and Duke University, Durham, North Carolina, USA
| | - Amy Yan
- Department of Surgery, Duke University, Durham, North Carolina, USA
| | - Telmo Llanga
- Department of Surgery, Duke University, Durham, North Carolina, USA
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina, USA
| | - Bruce A Sullenger
- Department of Surgery, Duke University, Durham, North Carolina, USA
- University Program in Genetics and Genomics, and Duke University, Durham, North Carolina, USA
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina, USA
| |
Collapse
|
4
|
Requena MD, Gray BP, Sullenger BA. Protocol for purification of cells in their native state using reversible aptamer-antidote pairs. STAR Protoc 2023; 4:102348. [PMID: 37314924 PMCID: PMC10277588 DOI: 10.1016/j.xpro.2023.102348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 03/13/2023] [Accepted: 05/11/2023] [Indexed: 06/16/2023] Open
Abstract
Cell isolation from complex mixtures is a key step in many clinical and research applications, but standard isolation methods may affect the cell's biology and are difficult to reverse. Here, we present a method to isolate and restore cells to their native state using an aptamer that binds epidermal growth factor receptor (EGFR+)cells and a complementary antisense oligonucleotide to reverse binding. For complete details on the use and execution of this protocol, please refer to Gray et al.1.
Collapse
Affiliation(s)
- Martin D Requena
- Department of Surgery, Duke University Medical Center, 2 Genome Ct, Durham, NC 27710, USA; University Program in Genetics and Genomics, Duke University Medical Center, 2 Genome Ct, Durham, NC 27710, USA.
| | - Bethany Powell Gray
- Department of Surgery, Duke University Medical Center, 2 Genome Ct, Durham, NC 27710, USA; Department of Pharmacology and Molecular Sciences, The Johns Hopkins University School of Medicine, 725 North Wolfe St, Baltimore, MD 21205, USA
| | - Bruce A Sullenger
- Department of Surgery, Duke University Medical Center, 2 Genome Ct, Durham, NC 27710, USA; University Program in Genetics and Genomics, Duke University Medical Center, 2 Genome Ct, Durham, NC 27710, USA.
| |
Collapse
|
5
|
Bush K, Corsi GI, Yan AC, Haynes K, Layzer JM, Zhou JH, Llanga T, Gorodkin J, Sullenger BA. Utilizing directed evolution to interrogate and optimize CRISPR/Cas guide RNA scaffolds. Cell Chem Biol 2023; 30:879-892.e5. [PMID: 37390831 PMCID: PMC10529641 DOI: 10.1016/j.chembiol.2023.06.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 03/09/2023] [Accepted: 06/06/2023] [Indexed: 07/02/2023]
Abstract
CRISPR-based editing has revolutionized genome engineering despite the observation that many DNA sequences remain challenging to target. Unproductive interactions formed between the single guide RNA's (sgRNA) Cas9-binding scaffold domain and DNA-binding antisense domain are often responsible for such limited editing resolution. To bypass this limitation, we develop a functional SELEX (systematic evolution of ligands by exponential enrichment) approach, termed BLADE (binding and ligand activated directed evolution), to identify numerous, diverse sgRNA variants that bind Streptococcus pyogenes Cas9 and support DNA cleavage. These variants demonstrate surprising malleability in sgRNA sequence. We also observe that particular variants partner more effectively with specific DNA-binding antisense domains, yielding combinations with enhanced editing efficiencies at various target sites. Using molecular evolution, CRISPR-based systems could be created to efficiently edit even challenging DNA sequences making the genome more tractable to engineering. This selection approach will be valuable for generating sgRNAs with a range of useful activities.
Collapse
Affiliation(s)
- Korie Bush
- Department of Surgery, Duke University, Durham, NC 27710, USA; University Program in Genetics and Genomics, Duke University, Durham, NC 27710, USA; Moderna Genomics, Cambridge, MA 02139, USA
| | - Giulia I Corsi
- Center for non-Coding RNA in Technology and Health, Department of Veterinary and Animal Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark; Tessera Therapeutics, Somerville, MA 02143, USA
| | - Amy C Yan
- Department of Surgery, Duke University, Durham, NC 27710, USA
| | - Keith Haynes
- Department of Information Technology, Midlands Technical College, Columbia, SC 29202, USA
| | | | - Jonathan H Zhou
- Department of Surgery, Duke University, Durham, NC 27710, USA; University Program in Genetics and Genomics, Duke University, Durham, NC 27710, USA
| | - Telmo Llanga
- Department of Surgery, Duke University, Durham, NC 27710, USA; Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA
| | - Jan Gorodkin
- Center for non-Coding RNA in Technology and Health, Department of Veterinary and Animal Sciences, University of Copenhagen, 1871 Frederiksberg, Denmark
| | - Bruce A Sullenger
- Department of Surgery, Duke University, Durham, NC 27710, USA; University Program in Genetics and Genomics, Duke University, Durham, NC 27710, USA; Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA; Department of Biomedical Engineering, Duke University, Durham, NC 27710, USA.
| |
Collapse
|
6
|
Yu H, Frederiksen J, Sullenger BA. Applications and future of aptamers that achieve rapid-onset anticoagulation. RNA 2023; 29:455-462. [PMID: 36697262 PMCID: PMC10019365 DOI: 10.1261/rna.079503.122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
In this short Perspective, we discuss the history of, and recent progress toward, the development of aptamers that can serve as rapid onset anticoagulants during cardiopulmonary bypass (CPB), extracorporeal membrane oxygenation (ECMO), and catheter-based diagnostic and interventional procedures, several million of which are performed each year worldwide. Aptamer anticoagulants provide potent and antidote-controllable anticoagulation and have low immunogenicity. New methods of aptamer isolation and engineering have not only improved the quality of aptamers, but also accelerated their development. Unfortunately, no aptamer identified to date can produce an anticoagulant effect as potent as that produced by unfractionated heparin (UFH), the standard anticoagulant for CPB. We have suggested several possible strategies to amplify the anticoagulant potency of existing aptamer anticoagulants.
Collapse
Affiliation(s)
- Haixiang Yu
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - James Frederiksen
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA
| | - Bruce A Sullenger
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27710, USA
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
| |
Collapse
|
7
|
Gray BP, Kelly L, Steen-Burrell KA, Layzer JM, Rempel RE, Nimjee SM, Cooley BC, Tarantal AF, Sullenger BA. Rapid molecular imaging of active thrombi in vivo using aptamer-antidote probes. Mol Ther Nucleic Acids 2023; 31:440-451. [PMID: 36817726 PMCID: PMC9930157 DOI: 10.1016/j.omtn.2023.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 01/19/2023] [Indexed: 01/22/2023]
Abstract
Pathological blood clotting, or thrombosis, limits vital blood flow to organs; such deprivation can lead to catastrophic events including myocardial infarction, pulmonary embolism, and ischemic stroke. Prompt restoration of blood flow greatly improves outcomes. We explored whether aptamers could serve as molecular imaging probes to rapidly detect thrombi. An aptamer targeting thrombin, Tog25t, was found to rapidly localize to and visualize pre-existing clots in the femoral and jugular veins of mice using fluorescence imaging and, when circulating, was able to image clots as they form. Since free aptamer is quickly cleared from circulation, contrast is rapidly developed, allowing clot visualization within minutes. Moreover, administration of an antidote oligonucleotide further enhanced contrast development, causing the unbound aptamer to clear within 5min while impacting the clot-bound aptamer more slowly. These findings suggest that aptamers can serve as imaging agents for rapid detection of thrombi in acute care and perioperative settings.
Collapse
Affiliation(s)
- Bethany Powell Gray
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | - Linsley Kelly
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | | | - Juliana M. Layzer
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | - Rachel E. Rempel
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | - Shahid M. Nimjee
- Department of Neurological Surgery, The Ohio State University Wexner Medical Center, Columbus, OH 43210, USA
| | - Brian C. Cooley
- Department of Pathology and Laboratory Medicine, University of North Carolina School of Medicine, Chapel Hill, NC 27599-7525, USA
| | - Alice F. Tarantal
- Departments of Pediatrics and Cell Biology and Human Anatomy, School of Medicine, and California National Primate Research Center, University of California Davis, Davis, CA 95616-8542, USA
| | - Bruce A. Sullenger
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
- Departments of Pharmacology & Cancer Biology and Biomedical Engineering, Duke University, Durham, NC 27710, USA
| |
Collapse
|
8
|
Puzzo F, Zhang C, Powell Gray B, Zhang F, Sullenger BA, Kay MA. Aptamer-programmable adeno-associated viral vectors as a novel platform for cell-specific gene transfer. Mol Ther Nucleic Acids 2023; 31:383-397. [PMID: 36817723 PMCID: PMC9929486 DOI: 10.1016/j.omtn.2023.01.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 01/19/2023] [Indexed: 01/22/2023]
Abstract
Adeno-associated viruses (AAVs) are commonly used for in vivo gene therapy. Nevertheless, the wide tropism that characterizes these vectors limits specific targeting to a particular cell type or tissue. Here, we developed new chemically modified AAV vectors (Nε-AAVs) displaying a single site substitution on the capsid surface for post-production vector engineering through biorthogonal copper-free click chemistry. We were able to identify AAV vectors that would tolerate the unnatural amino acid substitution on the capsid without disrupting their packaging efficiency. We functionalized the Nε-AAVs through conjugation with DNA (AS1411) or RNA (E3) aptamers or with a folic acid moiety (FA). E3-, AS1411-, and FA-AAVs showed on average a 3- to 9-fold increase in transduction compared with their non-conjugated counterparts in different cancer cell lines. Using specific competitors, we established ligand-specific transduction. In vivo studies confirmed the selective uptake of FA-AAV and AS1411-AAV without off-target transduction in peripheral organs. Overall, the high versatility of these novel Nε-AAVs might pave the way to tailoring gene therapy vectors toward specific types of cells both for ex vivo and in vivo applications.
Collapse
Affiliation(s)
- Francesco Puzzo
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA
| | - Chuanling Zhang
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA
- State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Bethany Powell Gray
- Department of Surgery, Duke University School of Medicine, Durham, NC 27705, USA
| | - Feijie Zhang
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA
| | - Bruce A. Sullenger
- Department of Surgery, Duke University School of Medicine, Durham, NC 27705, USA
| | - Mark A. Kay
- Departments of Pediatrics and Genetics, Stanford University, Stanford, CA 94305, USA
| |
Collapse
|
9
|
Olson LB, Hunter NI, Rempel RE, Yu H, Spencer DM, Sullenger CZ, Greene WS, Varanko AK, Eghtesadi SA, Chilkoti A, Pisetsky DS, Everitt JI, Sullenger BA. Mixed-surface polyamidoamine polymer variants retain nucleic acid-scavenger ability with reduced toxicity. iScience 2022; 25:105542. [PMID: 36444294 PMCID: PMC9700028 DOI: 10.1016/j.isci.2022.105542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/02/2022] [Accepted: 11/07/2022] [Indexed: 11/11/2022] Open
Abstract
Nucleic acid-binding polymers can have anti-inflammatory properties and beneficial effects in animal models of infection, trauma, cancer, and autoimmunity. PAMAM G3, a polyamidoamine dendrimer, is fully cationic bearing 32 protonable surface amines. However, while PAMAM G3 treatment leads to improved outcomes for mice infected with influenza, at risk of cancer metastasis, or genetically prone to lupus, its administration can lead to serosal inflammation and elevation of biomarkers of liver and kidney damage. Variants with reduced density of cationic charge through the interspersal of hydroxyl groups were evaluated as potentially better-tolerated alternatives. Notably, the variant PAMAM G3 50:50, similar in size as PAMAM G3 but with half the charge, was not toxic in cell culture, less associated with weight loss or serosal inflammation after parenteral administration, and remained effective in reducing glomerulonephritis in lupus-prone mice. Identification of such modified scavengers should facilitate their development as safe and effective anti-inflammatory agents.
Collapse
Affiliation(s)
- Lyra B. Olson
- Department of Surgery, Duke University, Durham, NC 27710, USA
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA
| | - Nicole I. Hunter
- Department of Surgery, Duke University, Durham, NC 27710, USA
- Department of Chemistry, Duke University, Durham, NC 27710, USA
| | | | - Haixiang Yu
- Department of Surgery, Duke University, Durham, NC 27710, USA
| | - Diane M. Spencer
- Department of Medicine and Immunology, Division of Rheumatology, Duke University Medical Center, Durham, NC 27710, USA
| | - Cynthia Z. Sullenger
- Department of Surgery, Duke University, Durham, NC 27710, USA
- Department of Biology, Duke University, Durham, NC 27710, USA
| | | | | | - Seyed A. Eghtesadi
- Department of Biomedical Engineering, Duke University, Durham, NC 27710, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Duke University, Durham, NC 27710, USA
| | - David S. Pisetsky
- Department of Medicine and Immunology, Division of Rheumatology, Duke University Medical Center, Durham, NC 27710, USA
- Medical Research Service, Veterans Administration Medical Center, Durham, NC 27705, USA
| | | | - Bruce A. Sullenger
- Department of Surgery, Duke University, Durham, NC 27710, USA
- Department of Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA
- Department of Biomedical Engineering, Duke University, Durham, NC 27710, USA
| |
Collapse
|
10
|
Mohan AA, Olson LB, Naqvi IA, Morrison SA, Kraft BD, Chen L, Que LG, Ma Q, Barkauskas CE, Kirk A, Nair SK, Sullenger BA, Kasotakis G. Age and Comorbidities Predict COVID-19 Outcome, Regardless of Innate Immune Response Severity: A Single Institutional Cohort Study. Crit Care Explor 2022; 4:e0799. [PMID: 36506827 PMCID: PMC9726311 DOI: 10.1097/cce.0000000000000799] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The COVID-19 pandemic has claimed over eight hundred thousand lives in the United States alone, with older individuals and those with comorbidities being at higher risk of severe disease and death. Although severe acute respiratory syndrome coronavirus 2-induced hyperinflammation is one of the mechanisms underlying the high mortality, the association between age and innate immune responses in COVID-19 mortality remains unclear. DESIGN Flow cytometry of fresh blood and multiplexed inflammatory chemokine measurements of sera were performed on samples collected longitudinally from our cohort. Aggregate impact of comorbid conditions was calculated with the Charlson Comorbidity Index, and association between patient factors and outcomes was calculated via Cox proportional hazard analysis and repeated measures analysis of variance. SETTING A cohort of severely ill COVID-19 patients requiring ICU admission was followed prospectively. PATIENTS In total, 67 patients (46 male, age 59 ± 14 yr) were included in the study. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Mortality in our cohort was 41.8%. We identified older age (hazard ratio [HR] 1.09 [95% CI 1.07-1.11]; p = 0.001), higher comorbidity index (HR 1.24 [95% CI 1.14-1.35]; p = 0.039), and hyponatremia (HR 0.90 [95% CI 0.82-0.99]; p = 0.026) to each independently increase risk for death in COVID-19. We also found that neutrophilia (R = 0.2; p = 0.017), chemokine C-C motif ligand (CCL) 2 (R = 0.3; p = 0.043), and C-X-C motif chemokine ligand 9 (CXCL9) (R = 0.3; p = 0.050) were weakly but significantly correlated with mortality. Older age was associated with lower monocyte (R = -0.2; p = 0.006) and cluster of differentiation (CD) 16+ cell counts (R = -0.2; p = 0.002) and increased CCL11 concentration (R = 0.3; p = 0.050). Similarly, younger patients (< 65 yr) demonstrated a rise in CD4 (b-coefficient = 0.02; p = 0.036) and CD8 (0.01; p = 0.001) counts, as well as CCL20 (b-coefficient = 6.8; p = 0.036) during their ICU stay. This CD8 count rise was also associated with survival (b-coefficient = 0.01; p = 0.023). CONCLUSIONS Age, comorbidities, and hyponatremia independently predict mortality in severe COVID-19. Neutrophilia and higher CCL2 and CXCL9 levels are also associated with higher mortality, while independent of age.
Collapse
Affiliation(s)
| | - Lyra B Olson
- Department of Surgery, Duke University, Durham, NC
| | | | | | | | - Lingye Chen
- Department of Surgery, Duke University, Durham, NC
| | | | - Qing Ma
- Department of Surgery, Duke University, Durham, NC
| | | | - Allan Kirk
- Department of Surgery, Duke University, Durham, NC
| | - Smita K Nair
- Department of Surgery, Duke University, Durham, NC
- Departments of Neurosurgery and Pathology, Duke University, Durham, NC
| | - Bruce A Sullenger
- Department of Surgery, Duke University, Durham, NC
- Departments of Neurosurgery and Pathology, Duke University, Durham, NC
- Departments of Neurosurgery, Pharmacology, and Cancer Biology, Duke University, Durham, NC
| | | |
Collapse
|
11
|
Shea SM, Thomas KA, Rassam RMG, Mihalko EP, Daniel C, Sullenger BA, Spinella PC, Nimjee SM. Dose-Dependent Von Willebrand Factor Inhibition by Aptamer BB-031 Correlates with Thrombolysis in a Microfluidic Model of Arterial Occlusion. Pharmaceuticals (Basel) 2022; 15:ph15121450. [PMID: 36558901 PMCID: PMC9785393 DOI: 10.3390/ph15121450] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 11/14/2022] [Accepted: 11/16/2022] [Indexed: 11/24/2022] Open
Abstract
Von Willebrand Factor (VWF) plays a critical role in thrombus formation, stabilization, and propagation. Previous studies have demonstrated that targeted inhibition of VWF induces thrombolysis when administered in vivo in animal models of ischemic stroke. The study objective was to quantify dose-dependent inhibition of VWF-platelet function and its relationship with thrombolysis using BB-031, an aptamer that binds VWF and inhibits its function. VWF:Ac, VWF:RCo, T-TAS, and ristocetin-induced impedance aggregometry were used to assess BB-031-mediated inhibition of VWF. Reductions in original thrombus surface area and new deposition during administration of treatment were measured in a microfluidic model of arterial thrombolysis. Rotational thromboelastometry was used to assess changes in hemostasis. BB-031 induced maximal inhibition at the highest dose (3384 nM) in VWF:Ac, and demonstrated dose-dependent responses in all other assays. BB-031, but not vehicle, induced recanalization in the microfluidic model. Maximal lytic efficacy in the microfluidic model was seen at 1692 nM and not 3384 nM BB-031 when assessed by surface area. Minor changes in ROTEM parameters were seen at 3384 nM BB-031. Targeted VWF inhibition by BB-031 results in clinically measurable impairment of VWF function, and specifically VWF-GPIb function as measured by VWF:Ac. BB-031 also induced thrombolysis as measured in a microfluidic model of occlusion and reperfusion. Moderate correlation between inhibition and lysis was observed. Additional studies are required to further examine off-target effects of BB-031 at high doses, however, these are expected to be above the range of clinical targeted dosing.
Collapse
Affiliation(s)
- Susan M. Shea
- Division of Critical Care, Department of Pediatrics, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
- Correspondence: ; Tel.: +1-412-624-4872
| | - Kimberly A. Thomas
- Division of Critical Care, Department of Pediatrics, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Rassam M. G. Rassam
- Division of Critical Care, Department of Pediatrics, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Emily P. Mihalko
- Trauma and Transfusion Medicine Research Center, Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Christina Daniel
- Division of Critical Care, Department of Pediatrics, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Bruce A. Sullenger
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Philip C. Spinella
- Division of Critical Care, Department of Pediatrics, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Shahid M. Nimjee
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| |
Collapse
|
12
|
Abstract
Systemic lupus erythematosus (SLE) is a chronic and often progressive autoimmune disorder marked clinically by a variable constellation of symptoms including fatigue, rash, joint pains, and kidney damage. The lungs, heart, gastrointestinal system, and brain can also be impacted, and individuals with lupus are at higher risk for atherosclerosis, thrombosis, thyroid disease, and other disorders associated with chronic inflammation . Autoimmune diseases are marked by erroneous immune responses in which the target of the immune response is a "self"-antigen, or autoantigen, driven by the development of antigen-specific B or T cells that have overcome the normal systems of self-tolerance built into the development of B and T cells. SLE is specifically characterized by the production of autoantibodies against nucleic acids and their binding proteins, including anti-double stranded DNA, anti-Smith (an RNA binding protein), and many others . These antibodies bind their nuclear-derived antigens to form immune complexes that cause injury and scarring through direct deposition in tissues and activation of innate immune cells . In over 50% of SLE patients, immune complex aggregation in the kidneys drives intrarenal inflammation and injury and leads to lupus nephritis, a progressive destruction of the glomeruli that is one of the most common causes of lupus-related death . To counter this pathology increasing attention has turned to developing approaches to reduce the development and continued generation of such autoantibodies. In particular, the molecular and cellular events that lead to long term, continuous activation of such autoimmune responses have become the focus of new therapeutic strategies to limit renal and other pathologies in lupus patients. The focus of this review is to consider how the innate immune system is involved in the development and progression of lupus nephritis and how a novel approach to inhibit innate immune activation by neutralizing the activators of this response, called Damage Associated Molecular Patterns, may represent a promising approach to treat this and other autoimmune disorders.
Collapse
Affiliation(s)
- Lyra B Olson
- Department of Surgery, Duke University, Durham, North Carolina; Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina
| | - Nicole I Hunter
- Department of Surgery, Duke University, Durham, North Carolina; Department of Chemistry, Duke University, Durham, North Carolina
| | - Rachel E Rempel
- Department of Surgery, Duke University, Durham, North Carolina
| | - Bruce A Sullenger
- Department of Surgery, Duke University, Durham, North Carolina; Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina; Department of Biomedical Engineering, Duke University, Durham, North Carolina.
| |
Collapse
|
13
|
Corey KM, Olson LB, Naqvi IA, Morrison SA, Davis C, Nimjee SM, Que LG, Bachelder RE, Kraft BD, Chen L, Nair SK, Levy JH, Sullenger BA. Suppression of Fibrinolysis and Hypercoagulability, Severity of Hypoxemia, and Mortality in COVID-19 Patients: A Retrospective Cohort Study. Anesthesiology 2022; 137:67-78. [PMID: 35412597 PMCID: PMC9250792 DOI: 10.1097/aln.0000000000004239] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND COVID-19 causes hypercoagulability, but the association between coagulopathy and hypoxemia in critically ill patients has not been thoroughly explored. This study hypothesized that severity of coagulopathy would be associated with acute respiratory distress syndrome severity, major thrombotic events, and mortality in patients requiring intensive care unit-level care. METHODS Viscoelastic testing by rotational thromboelastometry and coagulation factor biomarker analyses were performed in this prospective observational cohort study of critically ill COVID-19 patients from April 2020 to October 2020. Statistical analyses were performed to identify significant coagulopathic biomarkers such as fibrinolysis-inhibiting plasminogen activator inhibitor 1 and their associations with clinical outcomes such as mortality, extracorporeal membrane oxygenation requirement, occurrence of major thrombotic events, and severity of hypoxemia (arterial partial pressure of oxygen/fraction of inspired oxygen categorized into mild, moderate, and severe per the Berlin criteria). RESULTS In total, 53 of 55 (96%) of the cohort required mechanical ventilation and 9 of 55 (16%) required extracorporeal membrane oxygenation. Extracorporeal membrane oxygenation-naïve patients demonstrated lysis indices at 30 min indicative of fibrinolytic suppression on rotational thromboelastometry. Survivors demonstrated fewer procoagulate acute phase reactants, such as microparticle-bound tissue factor levels (odds ratio, 0.14 [0.02, 0.99]; P = 0.049). Those who did not experience significant bleeding events had smaller changes in ADAMTS13 levels compared to those who did (odds ratio, 0.05 [0, 0.7]; P = 0.026). Elevations in plasminogen activator inhibitor 1 (odds ratio, 1.95 [1.21, 3.14]; P = 0.006), d-dimer (odds ratio, 3.52 [0.99, 12.48]; P = 0.05), and factor VIII (no clot, 1.15 ± 0.28 vs. clot, 1.42 ± 0.31; P = 0.003) were also demonstrated in extracorporeal membrane oxygenation-naïve patients who experienced major thrombotic events. Plasminogen activator inhibitor 1 levels were significantly elevated during periods of severe compared to mild and moderate acute respiratory distress syndrome (severe, 44.2 ± 14.9 ng/ml vs. mild, 31.8 ± 14.7 ng/ml and moderate, 33.1 ± 15.9 ng/ml; P = 0.029 and 0.039, respectively). CONCLUSIONS Increased inflammatory and procoagulant markers such as plasminogen activator inhibitor 1, microparticle-bound tissue factor, and von Willebrand factor levels are associated with severe hypoxemia and major thrombotic events, implicating fibrinolytic suppression in the microcirculatory system and subsequent micro- and macrovascular thrombosis in severe COVID-19. EDITOR’S PERSPECTIVE
Collapse
Affiliation(s)
- Kristin M. Corey
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710
| | - Lyra B. Olson
- Duke Medical Scientist Training Program, Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710
| | - Ibtehaj A. Naqvi
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710
| | - Sarah A Morrison
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710
| | - Connor Davis
- Duke Institute for Health Innovation, Duke University School of Medicine, Durham, NC 27710
| | - Shahid M. Nimjee
- Department of Neurosurgery, The Ohio State University Medical Center, Columbus, OH 43203
| | - Loretta G. Que
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - Robin E. Bachelder
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710
| | - Bryan D. Kraft
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - Lingye Chen
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - Smita K. Nair
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710
| | - Jerrold H. Levy
- Departments of Anesthesiology, Critical Care, and Surgery, Duke University School of Medicine, Durham, NC 27710
| | - Bruce A. Sullenger
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710
| |
Collapse
|
14
|
Chabata CV, Frederiksen JW, Olson LB, Naqvi IA, Hall SE, Gunaratne R, Kraft BD, Que LG, Chen L, Sullenger BA. Combining Heparin and a FX/Xa Aptamer to Reduce Thrombin Generation in Cardiopulmonary Bypass and COVID-19. Nucleic Acid Ther 2022; 32:139-150. [PMID: 35021888 PMCID: PMC9221171 DOI: 10.1089/nat.2021.0077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 11/10/2021] [Indexed: 11/13/2022] Open
Abstract
Known limitations of unfractionated heparin (UFH) have encouraged the evaluation of anticoagulant aptamers as alternatives to UFH in highly procoagulant settings such as cardiopulmonary bypass (CPB). Despite progress, these efforts have not been totally successful. We take a different approach and explore whether properties of an anticoagulant aptamer can complement UFH, rather than replace it, to address shortcomings with UFH use. Combining RNA aptamer 11F7t, which targets factor X/Xa, with UFH (or low molecular weight heparin) yields a significantly enhanced anticoagulant cocktail effective in normal and COVID-19 patient blood. This aptamer-UFH combination (1) supports continuous circulation of human blood through an ex vivo membrane oxygenation circuit, as is required for patients undergoing CPB and COVID-19 patients requiring extracorporeal membrane oxygenation, (2) allows for a reduced level of UFH to be employed, (3) more effectively limits thrombin generation compared to UFH alone, and (4) is rapidly reversed by the administration of protamine sulfate, the standard treatment for reversing UFH clinically following CPB. Thus, the combination of factor X/Xa aptamer and UFH has significantly improved anticoagulant properties compared to UFH alone and underscores the potential of RNA aptamers to improve medical management of acute care patients requiring potent yet rapidly reversible anticoagulation.
Collapse
Affiliation(s)
- Charlene V. Chabata
- Department of Surgery, Department of Medicine, Duke University Medical Centre, Durham, North Carolina, USA
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina, USA
| | - James W. Frederiksen
- Department of Surgery, Department of Medicine, Duke University Medical Centre, Durham, North Carolina, USA
| | - Lyra B. Olson
- Department of Surgery, Department of Medicine, Duke University Medical Centre, Durham, North Carolina, USA
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina, USA
- Medical Scientist Training Program, Duke University, Durham, North Carolina, USA
| | - Ibtehaj A. Naqvi
- Department of Surgery, Department of Medicine, Duke University Medical Centre, Durham, North Carolina, USA
- Department of Anesthesiology, Department of Medicine, Duke University Medical Centre, Durham, North Carolina, USA
| | - Sharon E. Hall
- Division of Hematology, Department of Medicine, Duke University Medical Centre, Durham, North Carolina, USA
| | - Ruwan Gunaratne
- Department of Medicine, Stanford University Medical Center, Stanford, California, USA
| | - Bryan D. Kraft
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Loretta G. Que
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Lingye Chen
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Bruce A. Sullenger
- Department of Surgery, Department of Medicine, Duke University Medical Centre, Durham, North Carolina, USA
- Department of Pharmacology and Cancer Biology, Duke University, Durham, North Carolina, USA
| |
Collapse
|
15
|
Reed CR, Bonadonna D, Otto JC, McDaniel CG, Chabata CV, Kuchibhatla M, Frederiksen J, Layzer JM, Arepally GM, Sullenger BA, Tracy ET. Aptamer-based factor IXa inhibition preserves hemostasis and prevents thrombosis in a piglet model of ECMO. Molecular Therapy - Nucleic Acids 2022; 27:524-534. [PMID: 35036063 PMCID: PMC8728519 DOI: 10.1016/j.omtn.2021.12.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 12/09/2021] [Indexed: 11/30/2022]
Abstract
Extracorporeal membrane oxygenation (ECMO) requires anticoagulation to prevent clotting when the patient’s blood contacts the circuit. Unfractionated heparin (UFH) usually prevents clotting but can cause life-threatening bleeding. An anticoagulant that selectively inhibits the contact activation (intrinsic) pathway while sparing the tissue factor (extrinsic) pathway of coagulation might prevent clotting triggered by the circuit while permitting physiologic coagulation at surgical sites. DTRI-178 is an RNA anticoagulant aptamer conjugated to polyethylene glycol that increases its half-life in circulation. This aptamer is based on a previously described molecule (9.3t) that inhibits intrinsic tenase activity by binding to factor IXa on an exosite. Using a piglet model of pediatric venoarterial (VA) ECMO, we compared thromboprevention and blood loss using a single dose of DTRI-178 versus UFH. In each of five experiments, we subjected two litter-matched piglets, one anticoagulated with DTRI-178 and the other with UFH, to simultaneous 12-h periods of VA ECMO. Both anticoagulants achieved satisfactory and comparable thromboprotection. However, UFH piglets had increased surgical site bleeding and required significantly greater blood transfusion volumes than piglets anticoagulated with DTRI-178. Our results indicate that DTRI-178, an aptamer against factor IXa, may be feasible, safer, and result in fewer transfusions and clinical bleeding events in ECMO.
Collapse
Affiliation(s)
- Christopher R. Reed
- Department of Surgery, Duke University Medical Center and Health System, 2301 Erwin Road, Box 3443, Durham, NC 27710, USA
- Corresponding author Christopher R. Reed, MD, Department of Surgery, Duke University Medical Center and Health System, 2301 Erwin Road, Box 3443, Durham, NC 27710, USA
| | - Desiree Bonadonna
- Extracorporeal Life Support, Duke University Medical Center, Durham, NC 27710, USA
| | - James C. Otto
- Department of Surgery, Duke University Medical Center and Health System, 2301 Erwin Road, Box 3443, Durham, NC 27710, USA
| | | | - Charlene Vongai Chabata
- Departments of Surgery; and Pharmacology and Cancer Biology, Duke University, Durham, NC 27710, USA
| | - Maragatha Kuchibhatla
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC 27710, USA
| | - James Frederiksen
- Department of Surgery, Duke University Medical Center and Health System, 2301 Erwin Road, Box 3443, Durham, NC 27710, USA
| | - Juliana M. Layzer
- Duke University Clinical and Translational Science Institute, Durham, NC 27710, USA
| | - Gowthami M. Arepally
- Division of Hematology, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Bruce A. Sullenger
- Department of Surgery, Duke University Medical Center and Health System, 2301 Erwin Road, Box 3443, Durham, NC 27710, USA
| | - Elisabeth T. Tracy
- Department of Surgery, Duke University Medical Center and Health System, 2301 Erwin Road, Box 3443, Durham, NC 27710, USA
- Division of Pediatric Surgery, Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| |
Collapse
|
16
|
Ozer I, Pitoc GA, Layzer JM, Moreno A, Olson LB, Layzer KD, Hucknall AM, Sullenger BA, Chilkoti A. PEG-Like Brush Polymer Conjugate of RNA Aptamer That Shows Reversible Anticoagulant Activity and Minimal Immune Response. Adv Mater 2022; 34:e2107852. [PMID: 34994037 DOI: 10.1002/adma.202107852] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/28/2021] [Indexed: 06/14/2023]
Abstract
Ribonucleic acid (RNA) therapeutics are an emerging class of drugs. RNA aptamers are of significant therapeutic and clinical interest because their activity can be easily reversed in vivo-a useful feature that is difficult to achieve using other therapeutic modalities. Despite their therapeutic promise, RNA aptamers are limited by their poor blood circulation. The attachment of polyethylene glycol (PEG) to RNA aptamers addresses this limitation. However, an RNA aptamer-PEG conjugate that is a reversible anticoagulant fails in a clinical trial due to the reactivity of the conjugate with pre-existing PEG antibodies and has cast a pall over PEGylation of aptamers and other biologics, despite its long history of utility in drug delivery. Here, PEG antibody-reactivity of this RNA aptamer is eliminated by conjugating it to a next-generation PEG-like brush polymer-poly[(oligoethylene glycol) methyl ether methacrylate)] (POEGMA). The conjugate retained the drug's therapeutic action and the ability to be easily reversed. Importantly, this conjugate does not bind pre-existing PEG antibodies that are prevalent in humans and does not induce a humoral immune response against the polymer itself in mice. These findings suggest a path to rescuing the PEGylation of RNA therapeutics and vaccines from the deleterious side-effects of PEG.
Collapse
Affiliation(s)
- Imran Ozer
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - George A Pitoc
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
| | - Juliana M Layzer
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
- Duke Clinical and Translational Science Institute, Durham, NC, 27707, USA
| | - Angelo Moreno
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
| | - Lyra B Olson
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
| | - Kyle D Layzer
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
| | - Angus M Hucknall
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| | - Bruce A Sullenger
- Department of Surgery, Duke University Medical Center, Durham, NC, 27707, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA
| |
Collapse
|
17
|
Soule EE, Yu H, Olson L, Naqvi I, Kumar S, Krishnaswamy S, Sullenger BA. Generation of an anticoagulant aptamer that targets factor V/Va and disrupts the FVa-membrane interaction in normal and COVID-19 patient samples. Cell Chem Biol 2022; 29:215-225.e5. [PMID: 35114109 PMCID: PMC8808741 DOI: 10.1016/j.chembiol.2022.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 11/11/2021] [Accepted: 01/11/2022] [Indexed: 11/29/2022]
Abstract
Coagulation cofactors profoundly regulate hemostasis and are appealing targets for anticoagulants. However, targeting such proteins has been challenging because they lack an active site. To address this, we isolate an RNA aptamer termed T18.3 that binds to both factor V (FV) and FVa with nanomolar affinity and demonstrates clinically relevant anticoagulant activity in both plasma and whole blood. The aptamer also shows synergy with low molecular weight heparin and delivers potent anticoagulation in plasma collected from patients with coronavirus disease 2019 (COVID-19). Moreover, the aptamer's anticoagulant activity can be rapidly and efficiently reversed using protamine sulfate, which potentially allows fine-tuning of aptamer's activity post-administration. We further show that the aptamer achieves its anticoagulant activity by abrogating FV/FVa interactions with phospholipid membranes. Our success in generating an anticoagulant aptamer targeting FV/Va demonstrates the feasibility of using cofactor-binding aptamers as therapeutic protein inhibitors and reveals an unconventional working mechanism of an aptamer by interrupting protein-membrane interactions.
Collapse
Affiliation(s)
- Erin E. Soule
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC 27710, USA,Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Haixiang Yu
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Lyra Olson
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC 27710, USA,Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Ibtehaj Naqvi
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Shekhar Kumar
- The Children’s Hospital of Philadelphia, Division of Hematology, Department of Pediatrics, The University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Sriram Krishnaswamy
- The Children’s Hospital of Philadelphia, Division of Hematology, Department of Pediatrics, The University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Bruce A. Sullenger
- Department of Pharmacology & Cancer Biology, Duke University, Durham, NC 27710, USA,Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA,Corresponding author
| |
Collapse
|
18
|
Kelly L, Olson LB, Rempel RE, Everitt JI, Levine D, Nair SK, Davis ME, Sullenger BA. β-Cyclodextrin-containing polymer treatment of cutaneous lupus and influenza improves outcomes. Mol Ther 2022; 30:845-854. [PMID: 34628051 PMCID: PMC8821959 DOI: 10.1016/j.ymthe.2021.10.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 08/27/2021] [Accepted: 09/30/2021] [Indexed: 02/04/2023] Open
Abstract
Nucleic acid (NA)-containing damage- and pathogen-associated molecular patterns (DAMPs and PAMPs, respectively) are implicated in numerous pathological conditions from infectious diseases to autoimmune disorders. Nucleic acid-binding polymers, including polyamidoamine (PAMAM) dendrimers, have demonstrated anti-inflammatory properties when administered to neutralize DAMPs/PAMPs. The PAMAM G3 variant has been shown to have beneficial effects in a cutaneous lupus erythematosus (CLE) murine model and improve survival of mice challenged with influenza. Unfortunately, the narrow therapeutic window of cationic PAMAM dendrimers makes their clinical development challenging. An alternative nucleic acid-binding polymer that has been evaluated in humans is a linear β-cyclodextrin-containing polymer (CDP). CDP's characteristics prompted us to evaluate its anti-inflammatory potential in CLE autoimmune and influenza infectious disease mouse models. We report that CDP effectively inhibits NA-containing DAMP-mediated activation of Toll-like receptors (TLRs) in cell culture, improves healing in lupus mice, and does not immunocompromise treated animals upon influenza infection but improves survival even when administered 3 days after infection. Finally, as anticipated, we observe limited toxicity in animals treated with CDP compared with PAMAM G3. Thus, CDP is a new anti-inflammatory agent that may be readily translated to the clinic to combat diseases associated with pathological NA-containing DAMPs/PAMPs.
Collapse
Affiliation(s)
- Linsley Kelly
- Department of Surgery, Duke University, Durham, NC 27710, USA
| | - Lyra B Olson
- Department of Surgery, Department of Pharmacology and Cancer Biology, Duke Medical Scientist Training Program, Duke University, Durham, NC 27710, USA
| | - Rachel E Rempel
- Department of Surgery, Duke University, Durham, NC 27710, USA
| | | | - Dana Levine
- Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Smita K Nair
- Department of Surgery, Department of Neurosurgery, Department of Pathology, Duke University, Durham, NC 27710, USA
| | - Mark E Davis
- Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Bruce A Sullenger
- Department of Surgery, Department of Pharmacology and Cancer Biology, Department of Neurosurgery, Department of Biomedical Engineering, Duke University, Durham, NC 27710, USA.
| |
Collapse
|
19
|
Eteshola EOU, Landa K, Rempel RE, Naqvi IA, Hwang ES, Nair SK, Sullenger BA. Breast cancer-derived DAMPs enhance cell invasion and metastasis, while nucleic acid scavengers mitigate these effects. Mol Ther Nucleic Acids 2021; 26:1-10. [PMID: 34513289 PMCID: PMC8408553 DOI: 10.1016/j.omtn.2021.06.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 06/25/2021] [Indexed: 12/23/2022]
Abstract
Breast cancer (BC) is the most common malignancy in women. Particular subtypes with aggressive behavior are major contributors to poor outcomes. Triple-negative breast cancer (TNBC) is difficult to treat, pro-inflammatory, and highly metastatic. We demonstrate that TNBC cells express TLR9 and are responsive to TLR9 ligands, and treatment of TNBC cells with chemotherapy increases the release of nucleic-acid-containing damage-associated molecular patterns (NA DAMPs) in cell culture. Such culture-derived and breast cancer patient-derived NA DAMPs increase TLR9 activation and TNBC cell invasion in vitro. Notably, treatment with the polyamidoamine dendrimer generation 3.0 (PAMAM-G3) behaved as a nucleic acid scavenger (NAS) and significantly mitigates such effects. In mice that develop spontaneous BC induced by polyoma middle T oncoprotein (MMTV-PyMT), treatment with PAMAM-G3 significantly reduces lung metastasis. Thus, NAS treatment mitigates cancer-induced inflammation and metastasis and represents a novel therapeutic approach for combating breast cancer.
Collapse
Affiliation(s)
- Elias O U Eteshola
- Duke University School of Medicine, Department of Pharmacology and Cancer Biology, Durham, NC 27710, USA.,Duke University Medical Center, Department of Surgery, Durham, NC 27710, USA
| | - Karenia Landa
- Duke University Medical Center, Department of Surgery, Durham, NC 27710, USA
| | - Rachel E Rempel
- Duke University Medical Center, Department of Surgery, Durham, NC 27710, USA
| | - Ibtehaj A Naqvi
- Duke University Medical Center, Department of Surgery, Durham, NC 27710, USA
| | - E Shelley Hwang
- Duke University Medical Center, Department of Surgery, Durham, NC 27710, USA.,Duke Cancer Institute, Durham, NC 27710, USA
| | - Smita K Nair
- Duke University Medical Center, Department of Surgery, Durham, NC 27710, USA.,Duke Cancer Institute, Durham, NC 27710, USA
| | - Bruce A Sullenger
- Duke University School of Medicine, Department of Pharmacology and Cancer Biology, Durham, NC 27710, USA.,Duke University Medical Center, Department of Surgery, Durham, NC 27710, USA.,Duke Cancer Institute, Durham, NC 27710, USA
| |
Collapse
|
20
|
Heggestad JT, Britton RJ, Kinnamon DS, Wall SA, Joh DY, Hucknall AM, Olson LB, Anderson JG, Mazur A, Wolfe CR, Oguin TH, Sullenger BA, Burke TW, Kraft BD, Sempowski GD, Woods CW, Chilkoti A. Rapid test to assess the escape of SARS-CoV-2 variants of concern. Sci Adv 2021; 7:eabl7682. [PMID: 34860546 PMCID: PMC8641938 DOI: 10.1126/sciadv.abl7682] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 10/15/2021] [Indexed: 05/03/2023]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants are concerning in the ongoing coronavirus disease 2019 (COVID-19) pandemic. Here, we developed a rapid test, termed CoVariant-SCAN, that detects neutralizing antibodies (nAbs) capable of blocking interactions between the angiotensin-converting enzyme 2 receptor and the spike protein of wild-type (WT) SARS-CoV-2 and three other variants: B.1.1.7, B.1.351, and P.1. Using CoVariant-SCAN, we assessed neutralization/blocking of monoclonal antibodies and plasma from COVID-19–positive and vaccinated individuals. For several monoclonal antibodies and most plasma samples, neutralization against B.1.351 and P.1 variants is diminished relative to WT, while B.1.1.7 is largely cross-neutralized. We also showed that we can rapidly adapt the platform to detect nAbs against an additional variant—B.1.617.2 (Delta)—without reengineering or reoptimizing the assay. Results using CoVariant-SCAN are consistent with live virus neutralization assays and demonstrate that this easy-to-deploy test could be used to rapidly assess nAb response against multiple SARS-CoV-2 variants.
Collapse
Affiliation(s)
- Jacob T. Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Rhett J. Britton
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - David S. Kinnamon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Simone A. Wall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Daniel Y. Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Angus M. Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Lyra B. Olson
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jack G. Anderson
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Anna Mazur
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Cameron R. Wolfe
- Division of Infectious Diseases, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Thomas H. Oguin
- Department of Medicine and the Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Bruce A. Sullenger
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | - Thomas W. Burke
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Bryan D. Kraft
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Gregory D. Sempowski
- Department of Medicine and the Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Christopher W. Woods
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
- Department of Medicine and the Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| |
Collapse
|
21
|
Heggestad JT, Kinnamon DS, Olson LB, Liu J, Kelly G, Wall SA, Oshabaheebwa S, Quinn Z, Fontes CM, Joh DY, Hucknall AM, Pieper C, Anderson JG, Naqvi IA, Chen L, Que LG, Oguin T, Nair SK, Sullenger BA, Woods CW, Burke TW, Sempowski GD, Kraft BD, Chilkoti A. Multiplexed, quantitative serological profiling of COVID-19 from blood by a point-of-care test. Sci Adv 2021; 7:eabg4901. [PMID: 34172447 PMCID: PMC8232907 DOI: 10.1126/sciadv.abg4901] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 05/12/2021] [Indexed: 05/08/2023]
Abstract
Highly sensitive, specific, and point-of-care (POC) serological assays are an essential tool to manage coronavirus disease 2019 (COVID-19). Here, we report on a microfluidic POC test that can profile the antibody response against multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antigens-spike S1 (S1), nucleocapsid (N), and the receptor binding domain (RBD)-simultaneously from 60 μl of blood, plasma, or serum. We assessed the levels of antibodies in plasma samples from 31 individuals (with longitudinal sampling) with severe COVID-19, 41 healthy individuals, and 18 individuals with seasonal coronavirus infections. This POC assay achieved high sensitivity and specificity, tracked seroconversion, and showed good concordance with a live virus microneutralization assay. We can also detect a prognostic biomarker of severity, IP-10 (interferon-γ-induced protein 10), on the same chip. Because our test requires minimal user intervention and is read by a handheld detector, it can be globally deployed to combat COVID-19.
Collapse
Affiliation(s)
- Jacob T Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - David S Kinnamon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Lyra B Olson
- Duke Medical Scientist Training Program, Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jason Liu
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Garrett Kelly
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Simone A Wall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Solomon Oshabaheebwa
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Zachary Quinn
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Cassio M Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Daniel Y Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
- Division of Plastic, Maxillofacial, and Oral Surgery, Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Angus M Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
| | - Carl Pieper
- Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27708, USA
| | - Jack G Anderson
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Ibtehaj A Naqvi
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
| | - Lingye Chen
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Loretta G Que
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Thomas Oguin
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Smita K Nair
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Neurosurgery and Pathology, Duke University School of Medicine, Duke University, Durham, NC 27710, USA
| | - Bruce A Sullenger
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710, USA
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Christopher W Woods
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Thomas W Burke
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710, USA
| | - Gregory D Sempowski
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710, USA
| | - Bryan D Kraft
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708, USA.
| |
Collapse
|
22
|
Olson LB, Naqvi IA, Turner DJ, Morrison SA, Kraft BD, Chen L, Sullenger BA, Nair SK, Que LG, Levy JH. Key Pathogenic Factors in Coronavirus Disease 2019-Associated Coagulopathy and Acute Lung Injury Highlighted in a Patient With Copresentation of Acute Myelocytic Leukemia: A Case Report. A A Pract 2021; 15:e01432. [PMID: 33783367 PMCID: PMC8330627 DOI: 10.1213/xaa.0000000000001432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/08/2021] [Indexed: 01/02/2023]
Abstract
The role of concurrent illness in coronavirus disease 2019 (COVID-19) is unknown. Patients with leukemia may display altered thromboinflammatory responses. We report a 53-year-old man presenting with acute leukemia and COVID-19 who developed thrombotic complications and acute respiratory distress syndrome. Multiple analyses, including rotational thromboelastometry and flow cytometry on blood and bronchoalveolar lavage, are reported to characterize coagulation and immune profiles. The patient developed chemotherapy-induced neutropenia that may have protected his lungs from granulocyte-driven hyperinflammatory acute lung injury. However, neutropenia also alters viral clearing, potentially enabling ongoing viral propagation. This case depicts a precarious equilibrium between leukemia and COVID-19.
Collapse
Affiliation(s)
- Lyra B. Olson
- From the Duke Medical Scientist Training Program, Department of Pharmacology and Cancer Biology and
| | - Ibtehaj A. Naqvi
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina
| | - Daniel J. Turner
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Sarah A. Morrison
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina
| | - Bryan D. Kraft
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Lingye Chen
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Bruce A. Sullenger
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina
| | - Smita K. Nair
- Department of Surgery, Duke University School of Medicine, Durham, North Carolina
| | - Loretta G. Que
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Jerrold H. Levy
- Departments of Anesthesiology, Critical Care, and Surgery, Duke University School of Medicine, Durham, North Carolina
| |
Collapse
|
23
|
Olson LB, Naqvi IA, CHEN LINGYE, Que LG, KRAFT BRYAND, Nair SK, Nimjee SM, Sullenger BA. Abstract P102: Elevated Von Willebrand Factor in Patients Presenting With Large-Vessel Occlusion Stroke as First Symptom of COVID-19 Mirrors Levels in Patients With COVID-19 Requiring ICU-Level Care. Stroke 2021. [DOI: 10.1161/str.52.suppl_1.p102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Introduction:
COVID-19 is a coagulopathic disease marked by elevated d-dimers, fibrinogen, and von Willebrand factor (vWF) levels accompanying arterial and venous thrombosis. While the majority of thrombotic events associated with COVID-19 occur in hospitalized patients, a subset of patients with minimal risk factors for CVA but with positive SARS-CoV-2 testing present with stroke as presumed first manifestation of infection. It is unclear if the pro-coagulant milieu present in patients requiring hospitalization for the respiratory complications of COVID-19 is the same as that of patients who present with stroke as first symptom of disease.
Methods:
Following emergent revascularization, clinical vWF levels were measured in patients presenting with stroke who tested positive for COVID-19. In parallel, plasma vWF levels from 28 patients with COVID-19 requiring ICU-level care and 8 healthy volunteers were measured via ELISA.
Results:
Three otherwise healthy patients between the ages of 45-55 years with positive test for SARS-CoV-2 presented with large-vessel stroke. By comparison, the average age of non-COVID stroke patients was 66 years. The consistency of the clots extracted through the aspirating catheter was dark, gelatinous throughout, without evidence of calcification, and distal thrombosis was noted minutes after revascularization. The vWF level for one patient was 345%, while the other two patients had vWF levels >400% of normal, exceeding the upper limit of detection of clinical assays. In the ICU cohort, 12 of 28 had thrombotic events during hospitalization. vWF levels were elevated by a mean of 800% over healthy controls with a range of 230-1670%.
Conclusions:
vWF levels were markedly elevated in both ICU patients and stroke patients with COVID-19 with an overlapping range of elevation over healthy controls. This suggests that widespread endothelial inflammation accompanies infection with SARS-CoV-2 even in the absence of respiratory symptoms.
Collapse
|
24
|
Zakeri A, Jadhav AP, Sullenger BA, Nimjee SM. Ischemic stroke in COVID-19-positive patients: an overview of SARS-CoV-2 and thrombotic mechanisms for the neurointerventionalist. J Neurointerv Surg 2020; 13:202-206. [PMID: 33298508 DOI: 10.1136/neurintsurg-2020-016794] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 11/17/2020] [Accepted: 11/21/2020] [Indexed: 12/16/2022]
Abstract
Coronavirus disease 2019 (COVID-19) results from infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It was first reported in Wuhan, China in patients suffering from severe pneumonia and acute respiratory distress syndrome and has now grown into the first pandemic in over 100 years. Patients infected with SARS-CoV-2 develop arterial thrombosis including stroke, myocardial infarction and peripheral arterial thrombosis, all of which result in poor outcomes despite maximal medical, endovascular, and microsurgical treatment compared with non-COVID-19-infected patients. In this review we provide a brief overview of SARS-CoV-2, the infectious agent responsible for the COVID-19 pandemic, and describe the mechanisms responsible for COVID-19-associated coagulopathy. Finally, we discuss the impact of COVID-19 on ischemic stroke, focusing on large vessel occlusion.
Collapse
Affiliation(s)
- Amanda Zakeri
- Neurosurgery, The Ohio State University Medical Center, Columbus, Ohio, USA
| | | | - Bruce A Sullenger
- Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Shahid M Nimjee
- Neurosurgery, The Ohio State University Medical Center, Columbus, Ohio, USA
| |
Collapse
|
25
|
Heggestad JT, Kinnamon DS, Olson LB, Liu J, Kelly G, Wall SA, Fontes CM, Joh DY, Hucknall AM, Pieper C, Naqvi IA, Chen L, Que LG, Oguin T, Nair SK, Sullenger BA, Woods CW, Sempowski GD, Kraft BD, Chilkoti A. Multiplexed, quantitative serological profiling of COVID-19 from a drop of blood by a point-of-care test. medRxiv 2020:2020.11.05.20226654. [PMID: 33173900 PMCID: PMC7654894 DOI: 10.1101/2020.11.05.20226654] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Highly sensitive, specific, and point-of-care (POC) serological assays are an essential tool to manage the COVID-19 pandemic. Here, we report on a microfluidic, multiplexed POC test that can profile the antibody response against multiple SARS-CoV-2 antigens - Spike S1 (S1), Nucleocapsid (N), and the receptor binding domain (RBD) - simultaneously from a 60 microliter drop of blood, plasma, or serum. We assessed the levels of anti-SARS-CoV-2 antibodies in plasma samples from 19 individuals (at multiple time points) with COVID-19 that required admission to the intensive care unit and from 10 healthy individuals. This POC assay shows good concordance with a live virus microneutralization assay, achieved high sensitivity (100%) and specificity (100%), and successfully tracked the longitudinal evolution of the antibody response in infected individuals. We also demonstrated that we can detect a chemokine, IP-10, on the same chip, which may provide prognostic insight into patient outcomes. Because our test requires minimal user intervention and is read by a handheld detector, it can be globally deployed in the fight against COVID-19 by democratizing access to laboratory quality tests.
Collapse
Affiliation(s)
- Jacob T Heggestad
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - David S Kinnamon
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Lyra B Olson
- Duke Medical Scientist Training Program, Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710 USA
| | - Jason Liu
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Garrett Kelly
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Simone A Wall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Cassio M Fontes
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Daniel Y Joh
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
- Division of Plastic, Maxillofacial, and Oral Surgery, Department of Surgery, Duke University Medical Center, Durham NC 27710 USA
| | - Angus M Hucknall
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| | - Carl Pieper
- Departments of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC 27708 USA
| | - Ibtehaj A Naqvi
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710 USA
| | - Lingye Chen
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710 USA
| | - Loretta G Que
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710 USA
| | - Thomas Oguin
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710 USA
| | - Smita K Nair
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710 USA
- Department of Neurosurgery and Pathology, Duke University School of Medicine, Duke University, Durham, NC 27710 USA
| | - Bruce A Sullenger
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
- Department of Surgery, Duke University School of Medicine, Durham, NC 27710 USA
- Department of Pharmacology and Cancer Biology, Duke University School of Medicine, Durham, NC 27710 USA
| | - Christopher W Woods
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710 USA
- Center for Applied Genomics and Precision Medicine, Department of Medicine, Duke University, Durham, NC 27710 USA
| | - Gregory D Sempowski
- Department of Medicine and Duke Human Vaccine Institute, School of Medicine, Duke University, Durham, NC 27710 USA
| | - Bryan D Kraft
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Duke University Medical Center, Durham, NC 27710 USA
| | - Ashutosh Chilkoti
- Department of Biomedical Engineering, Pratt School of Engineering, Duke University, Durham, NC 27708 USA
| |
Collapse
|
26
|
Hu J, Hodgkinson CP, Pratt RE, Lee J, Sullenger BA, Dzau VJ. Enhancing cardiac reprogramming via synthetic RNA oligonucleotides. Mol Ther Nucleic Acids 2020; 23:55-62. [PMID: 33335792 PMCID: PMC7723775 DOI: 10.1016/j.omtn.2020.10.034] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 10/21/2020] [Indexed: 11/08/2022]
Abstract
Reprogramming scar fibroblasts into new heart muscle cells has the potential to restore function to the injured heart. However, the effectiveness of reprogramming is notably low. We have recently demonstrated that the effectiveness of reprogramming fibroblasts into heart muscle cells (cardiomyocytes) is increased by the addition of RNA-sensing receptor ligands. Clinical use of these ligands is problematic due to their ability to induce adverse inflammatory events. To overcome this issue, we sought to determine whether synthetic analogs of natural RNA-sensing receptor ligands, which avoid generating inflammatory insults and are nuclease resistant, would similarly enhance fibroblast reprogramming into cardiomyocytes. Indeed, one such stabilized RNA, ICR2, increased the expression of cardiomyocyte-specific mRNAs in reprogrammed fibroblasts. Moreover, ICR2 enhanced the ability of reprogramming factors to produce cardiomyocytes with mature sarcomeres. Knockdown assays indicated that the effects of ICR2 were mediated by the RNA-sensing receptors Rig-I and TLR3. In addition, ICR2 reduced the effective dose and number of reprogramming factors needed for efficient reprogramming. In summary, the synthetic RNA oligonucleotide ICR2 is a potential therapeutic agent to enhance cardiac reprogramming efficiency.
Collapse
Affiliation(s)
- Jiabiao Hu
- Mandel Center for Heart and Vascular Research, and the Duke Cardiovascular Research Center, Duke University Medical Center, Durham, NC 27710, USA
| | - Conrad P Hodgkinson
- Mandel Center for Heart and Vascular Research, and the Duke Cardiovascular Research Center, Duke University Medical Center, Durham, NC 27710, USA
| | - Richard E Pratt
- Mandel Center for Heart and Vascular Research, and the Duke Cardiovascular Research Center, Duke University Medical Center, Durham, NC 27710, USA
| | - JaeWoo Lee
- Department of Surgery, Duke University, Durham, NC 27710, USA
| | | | - Victor J Dzau
- Mandel Center for Heart and Vascular Research, and the Duke Cardiovascular Research Center, Duke University Medical Center, Durham, NC 27710, USA
| |
Collapse
|
27
|
Nimjee SM, Sullenger BA. Therapeutic Aptamers: Evolving to Find their Clinical Niche. Curr Med Chem 2020; 27:4181-4193. [PMID: 31573879 DOI: 10.2174/0929867326666191001125101] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 03/28/2019] [Accepted: 03/28/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND The discovery that short oligonucleotides, termed aptamers, can fold into three-dimensional structures that allow them to selectively bind and inhibit the activity of pathogenic proteins is now over 25 years old. The invention of the SELEX methodology heralded in an era in which such nucleic acid-based ligands could be generated against a wide variety of therapeutic targets. RESULTS A large number of aptamers have now been identified by combinatorial chemistry methods in the laboratory and moreover, an increasing number have been discovered in nature. The affinities and activities of such aptamers have often been compared to that of antibodies, yet only a few of these agents have made it into clinical studies compared to a large and increasing number of therapeutic antibodies. One therapeutic aptamer targeting VEGF has made it to market, while 3 others have advanced as far as phase III clinical trials. CONCLUSION In this manuscript, we hope the reader appreciates that the success of aptamers becoming a class of drugs is less about nucleic acid biochemistry and more about target validation and overall drug chemistry.
Collapse
Affiliation(s)
- Shahid M Nimjee
- Department of Neurological Surgery, Wexner Medical Center, The Ohio State University, Columbus, OH, United States
| | - Bruce A Sullenger
- Department of Surgery, Duke University Medical Center, Durham, NC, United States
| |
Collapse
|
28
|
LaCroix BL, Patierno BM, Sullenger BA, George DJ, Patierno SR, Freedman JA. Abstract B006: Development of a novel therapeutic splice-switching oligonucleotide targeting race-related androgen receptor signaling and aggressive prostate cancer. Cancer Epidemiol Biomarkers Prev 2020. [DOI: 10.1158/1538-7755.disp18-b006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Abstract
Background: Age-adjusted incidence and mortality rates for prostate cancer (PCa) among African American (AA) men are 1.6- and 2.4-fold greater, respectively, than among white men. The more aggressive characteristics of AA PCa account for a significant component of the PCa disparity, in addition to social determinants of health. Differences in androgenic activities in AA versus white populations and PCa patients have been observed and, clinically, AAs have a less complete response to androgen deprivation than whites do. One of the critical androgen receptor signaling targets in PCa is AR-V7, an androgen receptor variant that lacks the ligand-binding domain, is constitutively active, and associates with castration-resistant PCa, poorer clinical outcomes, and resistance to androgen ablation/androgen receptor inhibition therapies. This work addresses the urgent need to develop a novel therapeutic strategy capable of inhibiting AR-V7.
Methods: We have designed and synthesized a novel chemically modified splice switching oligonucleotide (SSO) to correct aberrant splicing leading to production of AR-V7 as well as a control scrambled SSO. After transfection of PCa cell lines derived from AA and white patients with these SSOs, we have examined AR-V7 as well as androgen receptor RNA and protein levels using qPCR and Western blot analysis, respectively. Resulting alterations in proliferation have been assessed by monitoring cell growth using an Incucyte Live-Cell Imaging System and associated software.
Results: Transfection of a panel of PCa cell lines derived from AA and white patients with AR-V7 SSO decreases AR-V7 RNA and protein in a dose-dependent manner while maintaining expression levels of full-length androgen receptor. Preliminary data suggest this biochemical response correlates with a biologically significant phenotype. AR-V7 SSO decreases proliferation in PCa cells, including proliferation in the presence of the androgen receptor inhibitor, enzalutamide, over and above the reduction seen in response to enzalutamide alone in both enzalutamide-sensitive and -resistant PCa cell lines. Additionally, transfection of PCa cells with SSOs designed to target nearby splicing enhancer sequences partially reduces AR-V7 RNA expression. Further studies to examine the effects of this SSO on transactivation activity, signaling and PCa cell biology, and the therapeutic efficacy of this SSO in AA and white PCa patient-derived primary cell lines and xenografts are under way.
Conclusions: These studies suggest that a SSO can be developed to modulate androgen receptor signaling, inhibiting constitutive signaling and restoring ligand dependency, with interference of nearby splicing enhancer sequences contributing to its function. Such an SSO could represent a novel therapeutic strategy with the potential to reduce PCa disparities for AA men and improve outcomes for men of all races with aggressive disease driven by this mechanism.
Citation Format: Bonnie L. LaCroix, Brendon M. Patierno, Bruce A. Sullenger, Daniel J. George, Steven R. Patierno, Jennifer A. Freedman. Development of a novel therapeutic splice-switching oligonucleotide targeting race-related androgen receptor signaling and aggressive prostate cancer [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr B006.
Collapse
|
29
|
Abstract
The first clinical studies utilizing RNA-guided endonucleases (RGENs) to therapeutically edit RNA and DNA in cancer patients were recently published. These groundbreaking technological advances promise to revolutionize genetic therapy and, as I discuss, represent the culmination of decades of innovative work to engineer RGENs for such editing applications.
Collapse
Affiliation(s)
- Bruce A Sullenger
- Departments of Surgery, Pharmacology and Cancer Biology, and Biomedical Engineering, Duke University, 2 Genome Ct, Durham, NC 27710, USA.
| |
Collapse
|
30
|
Eteshola EO, Landa K, Hwang ES, Moreno A, Nair SK, Sullenger BA. Abstract A90: Blocking proinvasive signaling and inflammatory activation in triple-negative breast cancer with nucleic-acid scavengers (NAS). Cancer Immunol Res 2020. [DOI: 10.1158/2326-6074.tumimm19-a90] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Breast cancers (BC) remain the most lethal malignancies among women worldwide and the second leading cause of cancer-related mortalities in the US. Subtype heterogeneity and aggressive invasive potential are believed to be the major contributors of these outcomes. BC lacking canonical histologic receptors (i.e., ER/PR/HER2), called triple negative (TNBC), are notoriously aggressive, difficult to treat, and metastatic. It has been observed that the degree of inflammation-driven tumorigenesis tends to correlate with increased levels of cell free DNA (cfDNA) and other damage-associated molecular patterns (DAMPs) in cancer patient sera. Our lab has previously shown that nucleic-acid scavengers (NAS) can block proinflammatory and proinvasive/metastatic signals elicited by nucleic acid-containing DAMP activation of innate immune sensors such as of the Toll-like receptors (TLRs). Recently, we showed that treatment with the nucleic acid-binding polymer, PAMAM-G3, resulted in a drastic reduction in metastatic tumor burden to the liver in an immunocompetent murine model of pancreatic cancer (Naqvi I, Gunaratne R, et al., Mol Ther 2018;26). Ongoing work has shown that chemotherapy-derived TNBC-conditioned media (CM) and TNBC patient sera greatly increase TNBC cell invasion in vitro and that treatment with the NAS PAMAM-G3 significantly inhibits this effect. Treatment of the human monocyte cell line, THP-1, with TNBC CM elicited a very strong proinflammatory response comparable to known innate immune stimulants such as poly(I:C), LPS, and CpG, with elevated levels of IL-8, IL-6, MCP-1 (CCL2), IL-18, and IL-1β. Other biologically relevant immune responders such as isolated human PBMCs and whole blood will be tested to determine the potential impact on the tumor immune microenvironment during tumorigenesis and treatment. To elucidate the mechanism by which this NAS works in these tumor settings, our lab has developed several PAMAM-G3 derivatives, including biotin, IR-, and near-IR fluorophore-labeled molecules. These molecules will allow us to conduct DAMP capture and characterization experiments, as well as perform in vitro and in vivo live imaging experiments to gain insight into NAS PK/PD properties. Mechanistic insight into NAS antimetastatic and anti-inflammatory capabilities will enhance our understanding of metastatic progression and its interplay with the immune system. Moreover, these principles will aid in the development of novel of antimetastatic therapies to improve TNBC patient outcomes.
Citation Format: Elias O.U. Eteshola, Karenia Landa, E. Shelley Hwang, Angelo Moreno, Smita K. Nair, Bruce A. Sullenger. Blocking proinvasive signaling and inflammatory activation in triple-negative breast cancer with nucleic-acid scavengers (NAS) [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr A90.
Collapse
|
31
|
Gray BP, Requena MD, Nichols MD, Sullenger BA. Aptamers as Reversible Sorting Ligands for Preparation of Cells in Their Native State. Cell Chem Biol 2019; 27:232-244.e7. [PMID: 31879266 DOI: 10.1016/j.chembiol.2019.12.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 11/01/2019] [Accepted: 12/05/2019] [Indexed: 12/13/2022]
Abstract
Although antibodies are routinely used to label and isolate a desired cell type from a more complex mixture of cells, via either fluorescence-activated cell sorting (FACS) or magnetic-activated cell sorting (MACS), such antibody labeling is not easily reversible. We describe an FACS and MACS compatible method to reversibly label and purify cells using aptamers. Magnetic beads loaded with the epidermal growth factor receptor (EGFR)-binding antagonistic aptamer E07 specifically isolated EGFR-expressing cells, and pure, label-free cells were recovered via treatment with an "antidote" oligonucleotide complementary to the aptamer. Additionally, while FACS sorting cells with E07 or EGFR antibody yielded EGFR(+) cells with impeded EGFR signaling, stripping off the aptamer via antidote treatment restored receptor function, returning cells to their native state, which was not possible with the antibody. The ability to reversibly label or isolate cells without compromising their function is a valuable, versatile tool with important implications for both the laboratory and clinic.
Collapse
Affiliation(s)
- Bethany Powell Gray
- Department of Surgery, Duke University Medical Center, 2 Genome Ct, Durham, NC 27710, USA
| | - Martin D Requena
- Department of Surgery, Duke University Medical Center, 2 Genome Ct, Durham, NC 27710, USA
| | - Michael D Nichols
- Department of Biomedical Engineering, Duke University, 101 Science Dr, Durham, NC 27710, USA
| | - Bruce A Sullenger
- Department of Surgery, Duke University Medical Center, 2 Genome Ct, Durham, NC 27710, USA; Department of Biomedical Engineering, Duke University, 101 Science Dr, Durham, NC 27710, USA.
| |
Collapse
|
32
|
Eteshola EO, Naqvi IA, Gunaratne R, Moreno A, Nair SK, Sullenger BA. Abstract 4515: Utilizing nucleic-acid scavengers (NASs) to inhibit proinflammatory and proinvasive signaling in triple-negative breast cancer. Cancer Res 2019. [DOI: 10.1158/1538-7445.am2019-4515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Breast cancers (BC) remain the most lethal malignancies amongst women worldwide and the second leading cause of cancer-related mortalities in the US. Subtype heterogeneity and aggressive invasive potential are believed to be the major contributors of these outcomes. BC lacking canonical histological receptors (i.e. ER/PR/HER2), called triple-negative (TNBC), are notoriously aggressive, difficult-to-treat, and metastatic. It has been observed that the degree of inflammation-driven tumorigenesis tends to correlate with increased levels of cell-free DNA (cfDNA) in cancer patient sera. Our lab had previously shown that nucleic-acid scavengers (NASs) could be used to block the pro-inflammatory and pro-invasive/metastatic signals (e.g. DAMPs) elicited by these cfDNA/RNA likely through innate immune sensors such as of the toll-like receptors (TLRs). Recently, we showed that treatment with the cationic polymer NAS, PAMAM-G3, elicited a drastic reduction in metastatic tumor burden to the liver in an immune-competent murine model of pancreatic cancer (I. Naqvi & R. Gunaratne et al., Molecular Therapy 26, 2018). Ongoing work has shown that both chemotherapy-derived TNBC conditioned media and a TLR9 agonist greatly increased TNBC in vitro invasion and was significantly inhibited upon treatment with PAMAM-G3. To elucidate the mechanism by which this NAS works in these tumor settings, our lab has developed several PAMAM-G3 derivatives, including biotin, IR-, and near-IR fluorophore labeled molecules. These molecules will allow us to conduct DAMP capture and characterization experiments, as well as perform in vitro and in vivo live imaging experiments to gain better insights into NAS PK/PD properties. Mechanistic insight into NAS anti-metastatic and anti-inflammatory capabilities will enhance our basic understanding of metastatic progression and its interplay with the immune system. Moreover, these principles will aid in the development of novel of anti-metastatic therapies to improve TNBC patient outcomes.
Citation Format: Elias O. Eteshola, Ibtehaj A. Naqvi, Ruwan Gunaratne, Angelo Moreno, Smita K. Nair, Bruce A. Sullenger. Utilizing nucleic-acid scavengers (NASs) to inhibit proinflammatory and proinvasive signaling in triple-negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4515.
Collapse
|
33
|
Moreno A, Pitoc GA, Ganson NJ, Layzer JM, Hershfield MS, Tarantal AF, Sullenger BA. Anti-PEG Antibodies Inhibit the Anticoagulant Activity of PEGylated Aptamers. Cell Chem Biol 2019; 26:634-644.e3. [PMID: 30827937 PMCID: PMC6707742 DOI: 10.1016/j.chembiol.2019.02.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Revised: 12/17/2018] [Accepted: 01/31/2019] [Indexed: 02/06/2023]
Abstract
Biopharmaceuticals have become increasingly attractive therapeutic agents and are often PEGylated to enhance their pharmacokinetics and reduce their immunogenicity. However, recent human clinical trials have demonstrated that administration of PEGylated compounds can evoke anti-PEG antibodies. Considering the ubiquity of PEG in commercial products and the presence of pre-existing anti-PEG antibodies in patients in large clinical trials evaluating a PEG-modified aptamer, we investigated how anti-PEG antibodies effect the therapeutic activities of PEGylated RNA aptamers. We demonstrate that anti-PEG antibodies can directly bind to and inhibit anticoagulant aptamer function in vitro and in vivo. Moreover, in parallel studies we detected the presence of anti-PEG antibodies in nonhuman primates after a single administration of a PEGylated aptamer. Our results suggest that anti-PEG antibodies can limit the activity of PEGylated drugs and potentially compromise the activity of otherwise effective therapeutic agents.
Collapse
Affiliation(s)
- Angelo Moreno
- Department of Molecular Genetics and Microbiology graduate program, Duke University, Durham, NC, USA,Department of Surgery, Duke University, Durham, NC, USA
| | | | - Nancy J. Ganson
- Department of Medicine, Duke University Medical Center, Durham, NC, USA
| | - Juliana M. Layzer
- Department of Surgery, Duke University, Durham, NC, USA,Duke Clinical and Translational Science Institute, Durham, NC, USA
| | | | - Alice F. Tarantal
- Departments of Pediatrics and Cell Biology and Human Anatomy, School of Medicine, NHLBI Center for Gene Transfer for Heart, Lung, and Blood Disease, and California National Primate Research Center, University of California, Davis, CA, USA
| | - Bruce A. Sullenger
- Department of Molecular Genetics and Microbiology graduate program, Duke University, Durham, NC, USA,Department of Surgery, Duke University, Durham, NC, USA,Contact Info: Corresponding Author and Lead Contact:
| |
Collapse
|
34
|
Nimjee SM, Dornbos D, Pitoc GA, Wheeler DG, Layzer JM, Venetos N, Huttinger A, Talentino SE, Musgrave NJ, Moody H, Rempel RE, Jones C, Carlisle K, Wilson J, Bratton C, Joseph ME, Khan S, Hoffman MR, Sommerville L, Becker RC, Zweier JL, Sullenger BA. Preclinical Development of a vWF Aptamer to Limit Thrombosis and Engender Arterial Recanalization of Occluded Vessels. Mol Ther 2019; 27:1228-1241. [PMID: 30987839 DOI: 10.1016/j.ymthe.2019.03.016] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 03/08/2019] [Accepted: 03/25/2019] [Indexed: 11/18/2022] Open
Abstract
Endothelial surface and circulating glycoprotein von Willebrand factor (vWF) regulates platelet adhesion and is associated with thrombotic diseases, including ischemic stroke, myocardial infarction, and peripheral vascular disease. Thrombosis, as manifested in these diseases, is the leading cause of disability and death in the western world. Current parenteral antithrombotic and thrombolytic agents used to treat these conditions are limited by a short therapeutic window, irreversibility, and major risk of hemorrhage. To overcome these limitations, we developed a novel anti-vWF aptamer, called DTRI-031, that selectively binds and inhibits vWF-mediated platelet adhesion and arterial thrombosis while enabling rapid reversal of this antiplatelet activity by an antidote oligonucleotide (AO). Aptamer DTRI-031 exerts dose-dependent inhibition of platelet aggregation and thrombosis in whole blood and mice, respectively. Moreover, DTRI-031 can achieve potent vascular recanalization of platelet-rich thrombotic occlusions in murine and canine carotid arteries. Finally, DTRI-031 activity is rapidly (<5 min) and completely reversed by AO administration in a murine saphenous vein hemorrhage model, and murine toxicology studies indicate the aptamer is well tolerated. These findings suggest that targeting vWF with an antidote-controllable aptamer potentially represents an effective and safer treatment for thrombosis patients having platelet-rich arterial occlusions in the brain, heart, or periphery.
Collapse
Affiliation(s)
- Shahid M Nimjee
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA.
| | - David Dornbos
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - George A Pitoc
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Debra G Wheeler
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Juliana M Layzer
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Nicholas Venetos
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Allyson Huttinger
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Spencer E Talentino
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Nicholas J Musgrave
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Holly Moody
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Rachel E Rempel
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Cheyenne Jones
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Kendyl Carlisle
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Jenna Wilson
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Camille Bratton
- Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Matthew E Joseph
- Department of Surgery, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Shoeb Khan
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Maureane R Hoffman
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
| | - Laura Sommerville
- Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
| | - Richard C Becker
- Department of Medicine, University of Cincinnati Medical Center, Cincinnati, OH 45219, USA
| | - Jay L Zweier
- Department of Internal Medicine, The Ohio State University Medical Center, Columbus, OH 43210, USA
| | - Bruce A Sullenger
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA.
| |
Collapse
|
35
|
Darrabie MD, Cheeseman J, Limkakeng AT, Borawski J, Sullenger BA, Elster EA, Kirk AD, Lee J. Toll-like receptor activation as a biomarker in traumatically injured patients. J Surg Res 2018; 231:270-277. [PMID: 30278940 DOI: 10.1016/j.jss.2018.05.059] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 03/25/2018] [Accepted: 05/25/2018] [Indexed: 01/17/2023]
Abstract
BACKGROUND Surgical insult and trauma have been shown to cause dysregulation of the immune and inflammatory responses. Interaction of damage-associated molecular patterns (DAMPs) with toll-like receptors (TLRs) initiates innate immune response and systemic inflammatory responses. Given that surgical patients produce high levels of circulating damage-associated molecular patterns, we hypothesized that plasma-activated TLR activity would be correlated to injury status and could be used to predict pathological conditions involving tissue injury. METHODS An observational study was performed using samples from a single-institution prospective tissue and data repository from a Level-1 trauma center. In vitro TLR 2, 3, 4, and 9 activation was determined in a TLR reporter assay after isolation of plasma from peripheral blood. We determined correlations between plasma-activated TLR activity and clinical course measures of severity. RESULTS Eighteen patients were enrolled (median Injury Severity Score 15 [interquartile range 10, 23.5]). Trauma resulted in significant elevation in circulation high mobility group box 1 as well as increase of plasma-activated TLR activation (2.8-5.4-fold) compared to healthy controls. There was no correlation between circulating high mobility group box 1 and trauma morbidity; however, the plasma-activated TLR activity was correlated with acute physiology and chronic health evaluation II scores (R square = 0.24-0.38, P < 0.05). Patients who received blood products demonstrated significant increases in the levels of plasma-activated TLRs 2, 3, 4, and 9 and had a trend toward developing systemic inflammatory response syndrome. CONCLUSIONS Further studies examining TLR modulation and signaling in surgical patients may assist in predictive risk modeling and reduction in morbidity and mortality.
Collapse
Affiliation(s)
| | | | | | - Joseph Borawski
- Department of Surgery, Duke University, Durham, North Carolina
| | | | - Eric A Elster
- Department of Surgery, Uniformed Services University of Health Sciences and Walter Reed National Military Medical Center, Bethesda, Maryland
| | - Allan D Kirk
- Department of Surgery, Duke University, Durham, North Carolina
| | - Jaewoo Lee
- Department of Surgery, Duke University, Durham, North Carolina.
| |
Collapse
|
36
|
Huttinger AL, Wheeler DG, Gnyawali S, Dornbos D, Layzer JM, Venetos N, Talentino S, Musgrave NJ, Jones C, Bratton C, Joseph ME, Sen C, Sullenger BA, Nimjee SM. Ferric Chloride-induced Canine Carotid Artery Thrombosis: A Large Animal Model of Vascular Injury. J Vis Exp 2018. [PMID: 30247470 DOI: 10.3791/57981] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Occlusive arterial thrombosis leading to cerebral ischemic stroke and myocardial infarction contributes to ~13 million deaths every year globally. Here, we have translated a vascular injury model from a small animal into a large animal (canine), with slight modifications that can be used for pre-clinical screening of prophylactic and thrombolytic agents. In addition to the surgical methods, the modified protocol describes the step-by-step methods to assess carotid artery canalization by angiography, detailed instructions to process both the brain and carotid artery for histological analysis to verify carotid canalization and cerebral hemorrhage, and specific parameters to complete an assessment of downstream thromboembolic events by utilizing magnetic resonance imaging (MRI). In addition, specific procedural changes from the previously well-established small animal model necessary to translate into a large animal (canine) vascular injury are discussed.
Collapse
Affiliation(s)
| | | | | | - David Dornbos
- Department of Neurological Surgery, Ohio State University
| | | | | | | | | | - Cheyenne Jones
- Department of Neurological Surgery, Ohio State University
| | | | | | - Chandan Sen
- Department of Surgery, Ohio State University
| | | | | |
Collapse
|
37
|
Gunaratne R, Kumar S, Frederiksen JW, Stayrook S, Lohrmann JL, Perry K, Bompiani KM, Chabata CV, Thalji NK, Ho MD, Arepally G, Camire RM, Krishnaswamy S, Sullenger BA. Combination of aptamer and drug for reversible anticoagulation in cardiopulmonary bypass. Nat Biotechnol 2018; 36:606-613. [PMID: 29863725 PMCID: PMC6349032 DOI: 10.1038/nbt.4153] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 03/27/2018] [Indexed: 02/05/2023]
Abstract
Unfractionated heparin (UFH), the standard anticoagulant for cardiopulmonary bypass (CPB) surgery, carries a risk of post-operative bleeding and is potentially harmful in patients with heparin-induced thrombocytopenia-associated antibodies. To improve the activity of an alternative anticoagulant, the RNA aptamer 11F7t, we solved X-ray crystal structures of the aptamer bound to factor Xa (FXa). The finding that 11F7t did not bind the catalytic site suggested that it could complement small-molecule FXa inhibitors. We demonstrate that combinations of 11F7t and catalytic-site FXa inhibitors enhance anticoagulation in purified reaction mixtures and plasma. Aptamer-drug combinations prevented clot formation as effectively as UFH in human blood circulated in an extracorporeal oxygenator circuit that mimicked CPB, while avoiding side effects of UFH. An antidote could promptly neutralize the anticoagulant effects of both FXa inhibitors. Our results suggest that drugs and aptamers with shared targets can be combined to exert more specific and potent effects than either agent alone.
Collapse
Affiliation(s)
- Ruwan Gunaratne
- Duke University, Department of Pharmacology and Cancer Biology, Durham, NC 27710
- Duke University, Medical Scientist Training Program, Durham, NC 27710
| | - Shekhar Kumar
- Research Institute, Children’s Hospital of Philadelphia, Philadelphia, PA 19104
| | | | - Steven Stayrook
- Department of Pediatrics, University of Pennsylvania, Philadelphia, PA 19104
| | | | - Kay Perry
- Northeastern Collaborative Access Team (NE-CAT) and Departments of Chemistry and Chemical Biology, Cornell University, Argonne National Laboratory, Argonne, IL 60439
| | | | - Charlene V. Chabata
- Duke University, Department of Pharmacology and Cancer Biology, Durham, NC 27710
| | - Nabil K. Thalji
- Research Institute, Children’s Hospital of Philadelphia, Philadelphia, PA 19104
- Department of Pediatrics, University of Pennsylvania, Philadelphia, PA 19104
| | - Michelle D. Ho
- Research Institute, Children’s Hospital of Philadelphia, Philadelphia, PA 19104
| | | | - Rodney M. Camire
- Research Institute, Children’s Hospital of Philadelphia, Philadelphia, PA 19104
- Department of Pediatrics, University of Pennsylvania, Philadelphia, PA 19104
| | - Sriram Krishnaswamy
- Research Institute, Children’s Hospital of Philadelphia, Philadelphia, PA 19104
- Department of Pediatrics, University of Pennsylvania, Philadelphia, PA 19104
| | - Bruce A. Sullenger
- Duke University, Department of Pharmacology and Cancer Biology, Durham, NC 27710
- Duke University, Department of Surgery, Durham, NC 27710
| |
Collapse
|
38
|
LaCroix BL, Patierno BM, Sullenger BA, George DJ, Patierno SR, Freedman JA. Abstract PR04: Development of a novel therapeutic splice-switching oligonucleotide targeting race-related androgen receptor signaling and aggressive prostate cancer. Cancer Epidemiol Biomarkers Prev 2018. [DOI: 10.1158/1538-7755.disp17-pr04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Abstract
Background: Age-adjusted incidence and mortality rates for prostate cancer (PCa) among African American (AA) men are 1.6- and 2.4-fold greater, respectively, than among white men. The more aggressive characteristics of AA PCa account for a significant component of the PCa disparity, in addition to social determinants of health. Differences in androgenic activities in AA versus white populations and PCa patients have been observed and, clinically, AAs have a less complete response to androgen deprivation than whites do. One of the critical androgen receptor signaling targets in PCa is AR-V7, an androgen receptor variant that lacks the ligand-binding domain, is constitutively active and associates with castration-resistant PCa, poorer clinical outcomes, and resistance to androgen ablation/androgen receptor inhibition therapies. This work addresses the urgent need to develop a novel therapeutic strategy capable of inhibiting AR-V7.
Methods: We have designed and synthesized a novel chemically modified splice switching oligonucleotide (SSO) to correct aberrant splicing leading to production of AR-V7 as well as a control scrambled SSO. After transfection of PCa cell lines derived from AA and white patients with these SSOs, we have examined AR-V7 as well as androgen receptor RNA and protein levels using qPCR and Western blot analysis, respectively. Resulting alterations in proliferation have been assessed by monitoring cell growth using an Incucyte Live-Cell Imaging System and associated software.
Results: Transfection of a panel of PCa cell lines derived from AA and white patients with AR-V7 SSO decreases AR-V7 RNA and protein in a dose-dependent manner while maintaining expression levels of full-length androgen receptor. Preliminary data suggest that this biochemical response correlates with a biologically significant phenotype. AR-V7 SSO decreases proliferation in PCa cells, including proliferation in the presence of the androgen receptor inhibitor, enzalutamide, over and above the reduction seen in response to enzalutamide alone in both enzalutamide-sensitive and -resistant PCa cell lines. Further studies to examine the effects of this SSO on transactivation activity, signaling, and PCa cell biology and the therapeutic efficacy of this SSO in AA and white PCa patient-derived primary cell lines and xenografts are under way.
Conclusions: These studies suggest that a SSO can be developed to modulate androgen receptor signaling, inhibiting constitutive signaling and restoring ligand dependency. Such a SSO could represent a novel therapeutic strategy with the potential to reduce PCa disparities for AA men and improve outcomes for men of all races with aggressive disease driven by this mechanism.
Citation Format: Bonnie L. LaCroix, Brendon M. Patierno, Bruce A. Sullenger, Daniel J. George, Steven R. Patierno, Jennifer A. Freedman. Development of a novel therapeutic splice-switching oligonucleotide targeting race-related androgen receptor signaling and aggressive prostate cancer [abstract]. In: Proceedings of the Tenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2017 Sep 25-28; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2018;27(7 Suppl):Abstract nr PR04.
Collapse
|
39
|
Affiliation(s)
- Bruce A Sullenger
- Department of Surgery, Duke Translational Research Institute, Duke University Medical Center , Durham, North Carolina
| |
Collapse
|
40
|
Abstract
Aptamers are single-stranded nucleic acid molecules that bind to and inhibit proteins and are commonly produced by systematic evolution of ligands by exponential enrichment (SELEX). Aptamers undergo extensive pharmacological revision, which alters affinity, specificity, and therapeutic half-life, tailoring each drug for a specific clinical need. The first therapeutic aptamer was described 25 years ago. Thus far, one aptamer has been approved for clinical use, and numerous others are in preclinical or clinical development. This review presents a short history of aptamers and SELEX, describes their pharmacological development and optimization, and reviews potential treatment of diseases including visual disorders, thrombosis, and cancer.
Collapse
Affiliation(s)
- Shahid M Nimjee
- Department of Neurological Surgery, The Ohio State University Wexner Medical Center, Columbus, Ohio 43210;
| | - Rebekah R White
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27705;
| | - Richard C Becker
- Department of Medicine, University of Cincinnati Medical Center, Cincinnati, Ohio 45267;
| | - Bruce A Sullenger
- Department of Surgery, Duke University Medical Center, Durham, North Carolina 27705; .,Duke Translational Research Institute, Duke University Medical Center, Durham, North Carolina 27705;
| |
Collapse
|
41
|
Steen Burrell KA, Layzer J, Sullenger BA. A kallikrein-targeting RNA aptamer inhibits the intrinsic pathway of coagulation and reduces bradykinin release. J Thromb Haemost 2017; 15:1807-1817. [PMID: 28632925 PMCID: PMC5818257 DOI: 10.1111/jth.13760] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Indexed: 01/29/2023]
Abstract
Essentials Kallikrein amplifies contact activation and is a potential target for preventing thrombosis. We developed and characterized a kallikrein aptamer using convergent evolution and kinetic assays. Kall1-T4 prolongs intrinsic clotting time by inhibiting factor XIIa-mediated prekallikrein activation. Kall1-T4 decreases high-molecular-weight kininogen cleavage and bradykinin release. SUMMARY Background Plasma kallikrein is a serine protease that plays an integral role in many biological processes, including coagulation, inflammation, and fibrinolysis. The main function of kallikrein in coagulation is the amplification of activated factor XII (FXIIa) production, which ultimately leads to thrombin generation and fibrin clot formation. Kallikrein is generated by FXIIa-mediated cleavage of the zymogen prekallikrein, which is usually complexed with the non-enzymatic cofactor high molecular weight kininogen (HK). HK also serves as a substrate for kallikrein to generate the proinflammatory peptide bradykinin (BK). Interestingly, prekallikrein-deficient mice are protected from thrombotic events while retaining normal hemostatic capacity. Therefore, therapeutic targeting of kallikrein may provide a safer alternative to traditional anticoagulants with anti-inflammatory benefits. Objectives To isolate and characterize an RNA aptamer that binds to and inhibits plasma kallikrein, and to elucidate its mechanism of action. Methods and Results Using convergent Systematic Evolution of Ligands by Exponential Enrichment (SELEX), we isolated an RNA aptamer that targets kallikrein. This aptamer, Kall1-T4, specifically binds to both prekallikrein and kallikrein with similar subnanomolar binding affinities, and dose-dependently prolongs fibrin clot formation in an activated partial thromboplastin time (APTT) coagulation assay. In a purified in vitro system, Kall1-T4 inhibits the reciprocal activation of prekallikrein and FXII primarily by reducing the rate of FXIIa-mediated prekallikrein activation. Additionally, Kall1-T4 significantly reduces kallikrein-mediated HK cleavage and subsequent BK release. Conclusions We have isolated a specific and potent inhibitor of prekallikrein/kallikrein activity that serves as a powerful tool for further elucidating the role of kallikrein in thrombosis and inflammation.
Collapse
Affiliation(s)
- K-A Steen Burrell
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
| | - J Layzer
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
| | - B A Sullenger
- Department of Surgery, Duke University Medical Center, Durham, NC, USA
| |
Collapse
|
42
|
Abstract
BACKGROUND The plasma protease factor XIa (FXIa) has become a target of interest for therapeutics designed to prevent or treat thrombotic disorders. METHODS We used a solution-based, directed evolution approach called systematic evolution of ligands by exponential enrichment (SELEX) to isolate RNA aptamers that target the FXIa catalytic domain. RESULTS Two aptamers, designated 11.16 and 12.7, were identified that bound to previously identified anion binding and serpin bindings sites on the FXIa catalytic domain. The aptamers were non-competitive inhibitors of FXIa cleavage of a tripeptide chromogenic substrate and of FXIa activation of factor IX. In normal human plasma, aptamer 12.7 significantly prolonged the aPTT clotting time. CONCLUSIONS The results show that novel inhibitors of FXIa can be prepared using SELEX techniques. RNA aptamers can bind to distinct sites on the FXIa catalytic domain and noncompetitively inhibit FXIa activity toward its primary macromolecular substrate factor IX with different levels of potency. Such compounds can be developed for use as therapeutic inhibitors.
Collapse
Affiliation(s)
- R S Woodruff
- Department of Surgery, Duke University Medical Center, Durham, NC, United States; University Program in Genetics and Genomics, Duke University, Durham, NC, United States
| | - I Ivanov
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - I M Verhamme
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - M-F Sun
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - D Gailani
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, United States
| | - B A Sullenger
- Department of Surgery, Duke University Medical Center, Durham, NC, United States.
| |
Collapse
|
43
|
Lee J, Jackman JG, Kwun J, Manook M, Moreno A, Elster EA, Kirk AD, Leong KW, Sullenger BA. Nucleic acid scavenging microfiber mesh inhibits trauma-induced inflammation and thrombosis. Biomaterials 2016; 120:94-102. [PMID: 28049065 DOI: 10.1016/j.biomaterials.2016.12.024] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 11/21/2016] [Accepted: 12/21/2016] [Indexed: 12/11/2022]
Abstract
Trauma patients produce a host of danger signals and high levels of damage-associated molecular patterns (DAMPs) after cellular injury and tissue damage. These DAMPs are directly and indirectly involved in the pathogenesis of various inflammatory and thrombotic complications in patients with severe injuries. No effective therapeutic agents for the removal of DAMPs from blood or tissue fluid have been developed. Herein, we demonstrated that nucleic acid binding polymers, e.g., polyethylenimine (PEI) and polyamidoamine dendrimers, immobilized onto electrospun microfiber mesh can effectively capture various DAMPs, such as extracellular DNAs and high mobility group box 1 (HMGB1). Furthermore, treatment with PEI-immobilized microfiber mesh abrogated the ability of DAMPs, released from dead and dying cells in culture or found in patients following traumatic injury, to activate innate immune responses and coagulation in vitro and in vivo. Nucleic acid scavenging microfiber meshes represent an effective strategy to combat inflammation and thrombosis in trauma.
Collapse
Affiliation(s)
- Jaewoo Lee
- Department of Surgery, Duke University, Durham, NC, 27710, USA.
| | - Jennifer G Jackman
- Department of Biomedical Engineering, Duke University, Durham, NC, 27710, USA
| | - Jean Kwun
- Department of Surgery, Duke University, Durham, NC, 27710, USA; Duke Transplant Center, Department of Surgery, Duke University, Durham, NC, 27710, USA
| | - Miriam Manook
- Department of Surgery, Duke University, Durham, NC, 27710, USA; Duke Transplant Center, Department of Surgery, Duke University, Durham, NC, 27710, USA
| | - Angelo Moreno
- Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, 27710, USA
| | - Eric A Elster
- Department of Surgery, Uniformed Services University of Health Sciences, Walter Reed National Military Medical Center, Bethesda, MD, 20814, USA
| | - Allan D Kirk
- Department of Surgery, Duke University, Durham, NC, 27710, USA; Duke Transplant Center, Department of Surgery, Duke University, Durham, NC, 27710, USA
| | - Kam W Leong
- Department of Biomedical Engineering, Duke University, Durham, NC, 27710, USA; Department of Biomedical Engineering, Columbia University, New York, NY, 10027, USA
| | - Bruce A Sullenger
- Department of Surgery, Duke University, Durham, NC, 27710, USA; Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, 27710, USA.
| |
Collapse
|
44
|
Abstract
Dying cells release nucleic acids (NA) and NA-containing complexes that activate inflammatory pathways of immune cells. Sustained activation of these pathways contributes to chronic inflammation frequently encountered in autoimmune and inflammatory diseases. In this study, grafting of cationic polymers onto a nanofibrous mesh enabled local scavenging of negatively charged pro-inflammatory molecules in the extracellular space. Nucleic acid scavenging nanofibers (NASFs) formed from poly(styrene-alt-maleic anhydride) conjugated with 1.8 kDa bPEI resulted in nanofibers of diameters 486 ± 9 nm. NASFs inhibited the NF-κB response stimulated by the negatively charged agonists, CpG and poly(I:C), in Ramos-blue cells but not Pam3CSK4, a nonanionic agonist. Moreover, NASFs significantly impeded NF-κB activation in cells stimulated with damage-associated molecular pattern molecules (DAMPs) released from doxorubicin killed cancer cells. In vivo application of NASFs to open wounds demonstrated nucleic acid scavenging in wounds of diabetic mice infected with Pseudomonas aeruginosa, suggesting the in vivo efficacy of NASFs. This simple technique of generating NASF results in effective localized anti-inflammation in vitro and local nucleic acid scavenging in vivo.
Collapse
Affiliation(s)
| | | | | | | | - Kam W Leong
- Department of Biomedical Engineering, Columbia University , New York, New York, United States
| | | |
Collapse
|
45
|
Kahsai AW, Wisler JW, Lee J, Ahn S, Cahill TJ, Dennison SM, Staus DP, Thomsen ARB, Anasti KM, Pani B, Wingler LM, Desai H, Bompiani KM, Strachan RT, Qin X, Alam SM, Sullenger BA, Lefkowitz RJ. Conformationally selective RNA aptamers allosterically modulate the β2-adrenoceptor. Nat Chem Biol 2016; 12:709-16. [PMID: 27398998 PMCID: PMC4990464 DOI: 10.1038/nchembio.2126] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 05/09/2016] [Indexed: 01/08/2023]
Abstract
G-protein-coupled receptor (GPCR) ligands function by stabilizing multiple, functionally distinct receptor conformations. This property underlies the ability of 'biased agonists' to activate specific subsets of a given receptor's signaling profile. However, stabilizing distinct active GPCR conformations to enable structural characterization of mechanisms underlying GPCR activation remains difficult. These challenges have accentuated the need for receptor tools that allosterically stabilize and regulate receptor function through unique, previously unappreciated mechanisms. Here, using a highly diverse RNA library combined with advanced selection strategies involving state-of-the-art next-generation sequencing and bioinformatics analyses, we identify RNA aptamers that bind a prototypical GPCR, the β2-adrenoceptor (β2AR). Using biochemical, pharmacological, and biophysical approaches, we demonstrate that these aptamers bind with nanomolar affinity at defined surfaces of the receptor, allosterically stabilizing active, inactive, and ligand-specific receptor conformations. The discovery of RNA aptamers as allosteric GPCR modulators significantly expands the diversity of ligands available to study the structural and functional regulation of GPCRs.
Collapse
Affiliation(s)
- Alem W. Kahsai
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710
| | - James W. Wisler
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710
| | - Jungmin Lee
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138
| | - Seungkirl Ahn
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710
| | - Thomas J. Cahill
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710
- Department of Biochemistry, Duke University Medical Center, Durham, NC, 27710
| | - S. Moses Dennison
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC, 27710
| | - Dean P. Staus
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710
| | - Alex R. B. Thomsen
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710
| | - Kara M. Anasti
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC, 27710
| | - Biswaranjan Pani
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710
| | - Laura M. Wingler
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710
| | - Hemant Desai
- The University of North Carolina School of Medicine, Chapel Hill, NC 27516
| | - Kristin M. Bompiani
- Department of Surgery, Duke University Medical Center, Durham, NC, 27710
- Duke Translational Research Institute, Duke University Medical Center, Durham, NC, 27710
- The University of California, San Diego, Moores Cancer Center, La Jolla, CA 92093
| | | | - Xiaoxia Qin
- Genome Sequencing and Analysis Core Resource, Duke University, Durham, NC, 27710
| | - S. Munir Alam
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC, 27710
| | - Bruce A. Sullenger
- Department of Surgery, Duke University Medical Center, Durham, NC, 27710
- Duke Translational Research Institute, Duke University Medical Center, Durham, NC, 27710
| | - Robert J. Lefkowitz
- Department of Medicine, Duke University Medical Center, Durham, NC, 27710
- Department of Biochemistry, Duke University Medical Center, Durham, NC, 27710
- Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC, 27710
| |
Collapse
|
46
|
Lee J, Xu L, Gibson TM, Gersbach CA, Sullenger BA. Differential effects of toll-like receptor stimulation on mRNA-driven myogenic conversion of human and mouse fibroblasts. Biochem Biophys Res Commun 2016; 478:1484-90. [PMID: 27586271 DOI: 10.1016/j.bbrc.2016.08.159] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 08/27/2016] [Indexed: 02/06/2023]
Abstract
Transfection with in vitro transcribed mRNAs is a safe and effective tool to convert somatic cells to any cell type of interest. One caveat of mRNA transfection is that mRNAs are recognized by multiple RNA-sensing toll like receptors (TLRs). These TLRs can both promote and inhibit cellular reprogramming. We demonstrated that mRNA transfection stimulated TLR3 and TLR7 and induced cytotoxicity and IFN-β expression in human and mouse fibroblasts. Furthermore, mRNA transfection induced paracrine inhibition of repeated mRNA transfection through type I IFNs. Modified mRNAs (mmRNAs) containing pseudouridine and 5-methycytosine reduced TLR stimulation, cytotoxicity and IFN-β expression in fibroblasts. Repeated liposomal transfection with MyoD mmRNAs significantly enhanced myogenic conversion of human and mouse fibroblasts compared with repeated transfection with MyoD mRNAs. Interestingly, electroporation of mRNAs and mmRNAs completely abrogated cytotoxicity and IFN-β expression and also abolished myogenic conversion of fibroblasts. At a low concentration, TLR7/8 agonist R848 enhanced MyoD mmRNA-driven conversion of human fibroblasts into skeletal muscle cells, whereas high concentrations of R848 inhibited myogenic conversion of fibroblasts. Our study suggests that deliberate control of TLR signaling is a key factor in the success of mRNA-driven cellular reprogramming.
Collapse
Affiliation(s)
- Jaewoo Lee
- Department of Surgery, Duke University, USA; Duke Translational Research Institute, Duke University Medical Center, Durham, NC 27710, USA.
| | - Li Xu
- Department of Surgery, Duke University, USA
| | - Tyler M Gibson
- Department of Biomedical Engineering, Duke University, USA
| | | | - Bruce A Sullenger
- Department of Surgery, Duke University, USA; Duke Translational Research Institute, Duke University Medical Center, Durham, NC 27710, USA.
| |
Collapse
|
47
|
Abstract
The study of RNA has continually emphasized the structural and functional versatility of RNA molecules. This versatility has inspired translational and clinical researchers to explore the utility of RNA-based therapeutic agents for a wide variety of medical applications. Several RNA therapeutics, with diverse modes of action, are being evaluated in large late-stage clinical trials, and many more are in early clinical development. Hundreds of patients are enrolled in large trials testing messenger RNAs to combat cancer, small interfering RNAs to treat renal and hepatic disorders, and aptamers to combat ocular and cardiovascular disease. Results from these studies are generating considerable interest among the biomedical community and the public and will be important for the future development of this emerging class of therapeutic agents.
Collapse
Affiliation(s)
- Bruce A Sullenger
- Duke Translational Research Institute and Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | - Smita Nair
- Duke Translational Research Institute and Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| |
Collapse
|
48
|
Nimjee SM, Povsic TJ, Sullenger BA, Becker RC. Translation and Clinical Development of Antithrombotic Aptamers. Nucleic Acid Ther 2016; 26:147-55. [PMID: 26882082 PMCID: PMC4900189 DOI: 10.1089/nat.2015.0581] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2015] [Accepted: 01/12/2016] [Indexed: 01/02/2023] Open
Abstract
Thrombosis is a necessary physiological process to protect the body from uncontrolled bleeding. Pathological thrombus formation can lead to devastating clinical events including heart attack, stroke, deep vein thrombosis, pulmonary embolism, and disseminated intravascular coagulation. Numerous drugs have been developed to inhibit thrombosis. These have been targeted to coagulation factors along with proteins and receptors that activate platelets. While these drugs are effective at preventing blood clotting, their major side effect is inadvertent hemorrhage that can result in significant morbidity and mortality. There exists a need for anticoagulants that are not only effective at preventing thrombosis but can also be readily reversed. Aptamers offer a potential solution, representing a new class of drug agents that can be isolated to any protein and where antidote oligonucleotides can be designed based on the sequence of the aptamer. We present a summary of the anticoagulant and antithrombotic aptamers that have been identified and their stage of development and comment on the future of aptamer-based drug development to treat thrombosis.
Collapse
Affiliation(s)
- Shahid M. Nimjee
- Department of Neurological Surgery, The Ohio State University Wexner Medical Center, Columbus, Ohio
| | - Thomas J. Povsic
- Duke Clinical Research Institute, Department of Medicine, Duke University Medical Center, Durham, North Carolina
| | - Bruce A. Sullenger
- Department of Surgery, Duke University Medical Center, Durham, North Carolina
| | - Richard C. Becker
- Department of Medicine, University of Cincinnati Medical Center, Cincinnati, Ohio
| |
Collapse
|
49
|
Mi J, Ray P, Liu J, Kuan CT, Xu J, Hsu D, Sullenger BA, White RR, Clary BM. In Vivo Selection Against Human Colorectal Cancer Xenografts Identifies an Aptamer That Targets RNA Helicase Protein DHX9. Mol Ther Nucleic Acids 2016; 5:e315. [PMID: 27115840 PMCID: PMC5014527 DOI: 10.1038/mtna.2016.27] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 03/10/2016] [Indexed: 12/25/2022]
Abstract
The ability to selectively target disease-related tissues with molecules is critical to the design of effective therapeutic and diagnostic reagents. Recognizing the differences between the in vivo environment and in vitro conditions, we employed an in vivo selection strategy to identify RNA aptamers (targeting motifs) that could localize to tumor in situ. One of the selected molecules is an aptamer that binds to the protein DHX9, an RNA helicase that is known to be upregulated in colorectal cancer. Upon systemic administration, the aptamer preferentially localized to the nucleus of cancer cells in vivo and thus has the potential to be used for targeted delivery.
Collapse
Affiliation(s)
- Jing Mi
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Partha Ray
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Jenny Liu
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Chien-Tsun Kuan
- Department of Pathology, Duke University Medical Center, Durham, North Carolina, USA
| | - Jennifer Xu
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - David Hsu
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | - Bruce A Sullenger
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Rebekah R White
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Bryan M Clary
- Department of Surgery, University of California at San Diego, La Jolla, California, USA
| |
Collapse
|
50
|
Freedman JA, Robinson TJ, LaCroix B, Patierno BM, George DJ, Sullenger BA, Patierno SR. Abstract B18: Development of novel therapeutic splice-switching oligonucleotides against aggressive prostate cancer in men of African descent. Cancer Epidemiol Biomarkers Prev 2016. [DOI: 10.1158/1538-7755.disp15-b18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Abstract
African American (AA) men exhibit a nearly 2-fold higher incidence and 3-fold higher mortality rate from prostate cancer compared to Caucasian American (CA) men and disparities in tumor aggressiveness remain after controlling for social determinants of health. Previous work from our laboratory and others has revealed differences in gene expression that contribute to prostate cancer health disparities among AAs. Oncogenic signaling pathways exhibiting up-regulation more often in AA prostate cancer include androgen receptor (AR) and epidermal growth factor receptor (EGFR). Thus, novel therapeutic strategies capable of driving production of inhibitory AR and EGFR isoforms and capable of limiting aberrant constitutively active AR isoforms are urgently needed. Such strategies will increase our understanding of these molecular mechanisms underlying prostate cancer in AA men. In addition, such strategies have the potential to ultimately result in novel specific approaches for treatment that will help reduce prostate cancer disparities for AAs and will improve treatment of advanced stage disease in all men with aggressive disease driven by these mechanisms.
Splice-switching oligonucleotides (SSOs) represent a novel therapeutic strategy to combat prostate cancer. Unlike the strategy of using RNA interference to inhibit the expression of a gene, SSOs simultaneously limit the production of pathogenic proteins and induce the expression of protein variants with therapeutic value. SSOs modulate pre-mRNA splicing by binding to target pre-mRNAs and blocking access of the splicing machinery to a particular splice site, and can be used to produce novel splice variants or correct aberrant splicing. Herein we have designed and synthesized novel SSOs targeting AR and EGFR pre-mRNAs to produce inhibitory splice variants and correct aberrant splicing as follows.
We have synthesized a SSO to correct the aberrant splicing that leads to production of the constitutively active AR-V7 variant leading to restoration of ligand dependency. Transfection of prostate cancer cells with this chemically modified SSO, which targets the splice site of the cryptic exon included in AR-V7, decreases AR-V7 RNA. In addition, we have synthesized a SSO to drive production of a naturally occurring dominant-negative AR variant (AR45) leading to interference with wild type AR transactivation activity. Transfection of prostate cancer cells with this chemically modified SSO, which targets the splice site of the first exon of wild type AR and leads to inclusion of an alternative first exon encoding the unique N-terminal extension characterizing AR45, increases AR45 RNA. Furthermore, we have synthesized SSOs targeting exons in the transmembrane domain and the tyrosine kinase domain of EGFR to drive production of a soluble, naturally expressed inhibitory EGFR isoform and a dominant-negative EGFR isoform, respectively. Transfection of prostate cancer cells with these chemically modified SSOs increase RNA corresponding to these isoforms. Studies are underway to examine the effects of these SSOs on AR and EGFR signaling, respectively, and the effects of these SSOs on prostate tumor cell biology.
These studies suggest that SSOs can be developed to modulate AR and EGFR signaling. Such SSOs have the potential to further our understanding of the contribution of the targeted molecular mechanisms to AA prostate cancer and have the potential to yield novel therapeutic modalities to combat prostate cancer in AA men as well as men of all races with aggressive disease driven by these mechanisms.
Citation Format: Jennifer A. Freedman, Timothy J. Robinson, Bonnie LaCroix, Brendon M. Patierno, Daniel J. George, Bruce A. Sullenger, Steven R. Patierno. Development of novel therapeutic splice-switching oligonucleotides against aggressive prostate cancer in men of African descent. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr B18.
Collapse
|