1
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Bernhard W, Barreto K, Toledo D, El-Sayed A, Jett KA, Casaco A, Fonge H, Geyer CR. Evaluation of nimotuzumab Fab 2 as an optical imaging agent in EGFR positive cancers. Sci Rep 2023; 13:10990. [PMID: 37419997 PMCID: PMC10328982 DOI: 10.1038/s41598-023-37873-9] [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: 03/20/2022] [Accepted: 06/28/2023] [Indexed: 07/09/2023] Open
Abstract
Molecular-targeted imaging probes can be used with a variety of imaging modalities to detect diseased tissues and guide their removal. EGFR is a useful biomarker for a variety of cancers, because it is expressed at high levels relative to normal tissues. Previously, we showed the anti-EGFR antibody nimotuzumab can be used as a positron emission tomography and fluorescent imaging probe for EGFR positive cancers in mice. These imaging probes are currently in clinical trials for PET imaging and image-guided surgery, respectively. One issue with using antibody probes for imaging is their long circulation time and slow tissue penetration, which requires patients to wait a few days after injection before imaging or surgery, multiple visits and longer radiation exposure. Here, we generated a Fab2 fragment of nimotuzumab, by pepsin digestion and labeled it with IRDye800CW to evaluate its optical imaging properties. The Fab2 had faster tumor accumulation and clearance in mice relative to the nimotuzumab IgG. The fluorescent signal peaked at 2 h post injection and remained high until 6 h post injection. The properties of the Fab2 allow a higher signal to background to be obtained in a shorter time frame, reducing the wait time for imaging after probe infusion.
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Affiliation(s)
- Wendy Bernhard
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Kris Barreto
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | | | - Ayman El-Sayed
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Kimberly A Jett
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | | | - Humphrey Fonge
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - C Ronald Geyer
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada.
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2
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Jett KA, Baker ZN, Hossain A, Boulet A, Cobine PA, Ghosh S, Ng P, Yilmaz O, Barreto K, DeCoteau J, Mochoruk K, Ioannou GN, Savard C, Yuan S, Abdalla OH, Lowden C, Kim BE, Cheng HYM, Battersby BJ, Gohil VM, Leary SC. Mitochondrial dysfunction reactivates α-fetoprotein expression that drives copper-dependent immunosuppression in mitochondrial disease models. J Clin Invest 2023; 133:154684. [PMID: 36301669 PMCID: PMC9797342 DOI: 10.1172/jci154684] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 10/26/2022] [Indexed: 02/04/2023] Open
Abstract
Signaling circuits crucial to systemic physiology are widespread, yet uncovering their molecular underpinnings remains a barrier to understanding the etiology of many metabolic disorders. Here, we identified a copper-linked signaling circuit activated by disruption of mitochondrial function in the murine liver or heart that resulted in atrophy of the spleen and thymus and caused a peripheral white blood cell deficiency. We demonstrated that the leukopenia was caused by α-fetoprotein, which required copper and the cell surface receptor CCR5 to promote white blood cell death. We further showed that α-fetoprotein expression was upregulated in several cell types upon inhibition of oxidative phosphorylation. Collectively, our data argue that α-fetoprotein may be secreted by bioenergetically stressed tissue to suppress the immune system, an effect that may explain the recurrent or chronic infections that are observed in a subset of mitochondrial diseases or in other disorders with secondary mitochondrial dysfunction.
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Affiliation(s)
- Kimberly A. Jett
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Canada
| | - Zakery N. Baker
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Canada
| | - Amzad Hossain
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Canada
| | - Aren Boulet
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Canada
| | - Paul A. Cobine
- Department of Biological Sciences, Auburn University, Auburn, Alabama, USA
| | - Sagnika Ghosh
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Philip Ng
- Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Orhan Yilmaz
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Canada
| | - Kris Barreto
- Department of Laboratory and Pathology Medicine, University of Saskatchewan, Saskatoon, Canada
| | - John DeCoteau
- Department of Laboratory and Pathology Medicine, University of Saskatchewan, Saskatoon, Canada
| | - Karen Mochoruk
- Department of Laboratory and Pathology Medicine, University of Saskatchewan, Saskatoon, Canada
| | - George N. Ioannou
- Division of Gastroenterology,,Research and Development, Veterans Affairs Puget Sound Health Care System and the,Division of Gastroenterology, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Christopher Savard
- Division of Gastroenterology,,Research and Development, Veterans Affairs Puget Sound Health Care System and the,Division of Gastroenterology, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Sai Yuan
- Department of Animal and Avian Sciences, University of Maryland, College Park, Maryland, USA
| | - Osama H.M.H. Abdalla
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
| | - Christopher Lowden
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
| | - Byung-Eun Kim
- Department of Animal and Avian Sciences, University of Maryland, College Park, Maryland, USA
| | - Hai-Ying Mary Cheng
- Department of Biology, University of Toronto Mississauga, Mississauga, Ontario, Canada.,Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
| | | | - Vishal M. Gohil
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, USA
| | - Scot C. Leary
- Department of Biochemistry, Microbiology and Immunology, University of Saskatchewan, Saskatoon, Canada
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3
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Maruthachalam BV, Barreto K, Hogan D, Kusalik A, Geyer CR. Generation of synthetic antibody fragments with optimal complementarity determining region lengths for Notch-1 recognition. Front Microbiol 2022; 13:931307. [PMID: 35992693 PMCID: PMC9381698 DOI: 10.3389/fmicb.2022.931307] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Accepted: 07/12/2022] [Indexed: 11/13/2022] Open
Abstract
Synthetic antibodies have been engineered against a wide variety of antigens with desirable biophysical, biochemical, and pharmacological properties. Here, we describe the generation and characterization of synthetic antigen-binding fragments (Fabs) against Notch-1. Three single-framework synthetic Fab libraries, named S, F, and modified-F, were screened against the recombinant human Notch-1 extracellular domain using phage display. These libraries were built on a modified trastuzumab framework, containing two or four diversified complementarity-determining regions (CDRs) and different CDR diversity designs. In total, 12 Notch-1 Fabs were generated with 10 different CDRH3 lengths. These Fabs possessed a high affinity for Notch-1 (sub-nM to mid-nM KDapp values) and exhibited different binding profiles (mono-, bi-or tri-specific) toward Notch/Jagged receptors. Importantly, we showed that screening focused diversity libraries, implementing next-generation sequencing approaches, and fine-tuning the CDR length diversity provided improved binding solutions for Notch-1 recognition. These findings have implications for antibody library design and antibody phage display.
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Affiliation(s)
| | - Kris Barreto
- Department of Biochemistry, University of Saskatchewan, Saskatoon, SK, Canada
| | - Daniel Hogan
- Department of Computer Science, University of Saskatchewan, Saskatoon, SK, Canada
| | - Anthony Kusalik
- Department of Computer Science, University of Saskatchewan, Saskatoon, SK, Canada
| | - Clarence Ronald Geyer
- Department of Pathology, University of Saskatchewan, Saskatoon, SK, Canada
- *Correspondence: Clarence Ronald Geyer,
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4
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Bernhard W, Barreto K, El-Sayed A, Gonzalez C, Viswas RS, Toledo D, Casaco A, DeCoteau J, Fonge H, Geyer CR. Pre-clinical study of IRDye800CW-nimotuzumab formulation, stability, pharmacokinetics, and safety. BMC Cancer 2021; 21:270. [PMID: 33711962 PMCID: PMC7953729 DOI: 10.1186/s12885-021-08003-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [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: 09/29/2020] [Accepted: 03/02/2021] [Indexed: 12/23/2022] Open
Abstract
Background Epidermal growth factor receptor (EGFR) is a target for cancer therapy as it is overexpressed in a wide variety of cancers. Therapeutic antibodies that bind EGFR are being evaluated in clinical trials as imaging agents for positron emission tomography and image-guided surgery. However, some of these antibodies have safety concerns such as infusion reactions, limiting their use in imaging applications. Nimotuzumab is a therapeutic monoclonal antibody that is specific for EGFR and has been used as a therapy in a number of countries. Methods Formulation of IRDye800CW-nimotuzumab for a clinical trial application was prepared. The physical, chemical, and pharmaceutical properties were tested to develop the specifications to determine stability of the product. The acute and delayed toxicities were tested and IRDye800CW-nimotuzumab was determined to be non-toxic. Non-compartmental pharmacokinetics analysis was used to determine the half-life of IRDye800CW-nimotuzumab. Results IRDye800CW-nimotuzumab was determined to be non-toxic from the acute and delayed toxicity study. The half-life of IRDye800CW-nimotuzumab was determined to be 38 ± 1.5 h. A bi-exponential analysis was also used which gave a t1/2 alpha of 1.5 h and t1/2 beta of 40.8 h. Conclusions Here, we show preclinical studies demonstrating that nimotuzumab conjugated to IRDye800CW is safe and does not exhibit toxicities commonly associated with EGFR targeting antibodies. Supplementary Information The online version contains supplementary material available at 10.1186/s12885-021-08003-3.
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Affiliation(s)
- Wendy Bernhard
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Kris Barreto
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Ayman El-Sayed
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Carolina Gonzalez
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Raja Solomon Viswas
- Department of Medical Imaging, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | | | | | - John DeCoteau
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada
| | - Humphrey Fonge
- Department of Medical Imaging, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada. .,Department of Medical Imaging, Royal University Hospital, Saskatoon, SK, Canada.
| | - Clarence Ronald Geyer
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon, SK, Canada.
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5
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Solomon VR, Alizadeh E, Bernhard W, Makhlouf A, Hartimath SV, Hill W, El-Sayed A, Barreto K, Geyer CR, Fonge H. Development and preclinical evaluation of cixutumumab drug conjugates in a model of insulin growth factor receptor I (IGF-1R) positive cancer. Sci Rep 2020; 10:18549. [PMID: 33122707 PMCID: PMC7596529 DOI: 10.1038/s41598-020-75279-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 09/29/2020] [Indexed: 12/25/2022] Open
Abstract
Overexpression of insulin growth factor receptor type 1 (IGF-1R) is observed in many cancers. Antibody drug conjugates (ADCs) with PEGylated maytansine (PEG6-DM1) show promise in vitro. We developed PEG6-DM1 ADCs with low and high drug to antibody ratios (DAR) using an anti-IGF-1R antibody cixutumumab (IMC-A12). Conjugates with low (cixutumumab-PEG6-DM1-Low) and high (cixutumumab-PEG6-DM1-High) DAR as 3.4 and 7.2, respectively, were generated. QC was performed by UV spectrophotometry, HPLC, bioanalyzer, and biolayer-interferometry. We compared the in vitro binding and internalization rates of the ADCs in IGF-1R-positive MCF-7/Her18 cells. We radiolabeled the ADCs with 111In and used microSPECT/CT imaging and ex vivo biodistribution to understand their in vivo behavior in MCF-7/Her18 xenograft mice. The therapeutic potential of the ADC was studied in vitro and in mouse xenograft. Internalization rates of all ADCs was high and increased over 48 h and EC50 was in the low nanomolar range. MicroSPECT/CT imaging and ex vivo biodistribution showed significantly lower tumor uptake of 111In-cixutumumab-PEG6-DM1-High compared to 111In-cixutumumab-PEG6-DM1-Low and 111In-cixutumumab. Cixutumumab-PEG6-DM1-Low significantly prolonged the survival of mice bearing MCF-7/Her18 xenograft compared with cixutumumab, cixutumumab-PEG6-DM1-High, or the PBS control group. Cixutumumab-PEG6-DM1-Low ADC was more effective. The study highlights the potential utility of cixutumumab-ADCs as theranostics against IGF-1R positive cancers.
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Affiliation(s)
- Viswas Raja Solomon
- Department of Medical Imaging, RUH Saskatoon, University of Saskatchewan, College of Medicine, 103 Hospital Dr., Saskatoon, SK, S7N 0W8, Canada
| | - Elahe Alizadeh
- Department of Medical Imaging, RUH Saskatoon, University of Saskatchewan, College of Medicine, 103 Hospital Dr., Saskatoon, SK, S7N 0W8, Canada
| | - Wendy Bernhard
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Amal Makhlouf
- Department of Medical Imaging, RUH Saskatoon, University of Saskatchewan, College of Medicine, 103 Hospital Dr., Saskatoon, SK, S7N 0W8, Canada.,Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Kasr El-Aini, Cairo, 12411, Egypt
| | - Siddesh V Hartimath
- Department of Medical Imaging, RUH Saskatoon, University of Saskatchewan, College of Medicine, 103 Hospital Dr., Saskatoon, SK, S7N 0W8, Canada
| | - Wayne Hill
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Ayman El-Sayed
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Kris Barreto
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Clarence Ronald Geyer
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Humphrey Fonge
- Department of Medical Imaging, RUH Saskatoon, University of Saskatchewan, College of Medicine, 103 Hospital Dr., Saskatoon, SK, S7N 0W8, Canada. .,Department of Medical Imaging, Royal University Hospital Saskatoon, Saskatoon, SK, Canada.
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6
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Barreto K, Maruthachalam BV, Hill W, Hogan D, Sutherland AR, Kusalik A, Fonge H, DeCoteau JF, Geyer CR. Next-generation sequencing-guided identification and reconstruction of antibody CDR combinations from phage selection outputs. Nucleic Acids Res 2019; 47:e50. [PMID: 30854567 PMCID: PMC6511873 DOI: 10.1093/nar/gkz131] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 12/12/2018] [Accepted: 03/07/2019] [Indexed: 12/12/2022] Open
Abstract
Next-generation sequencing (NGS) technologies have been employed in several phage display platforms for analyzing natural and synthetic antibody sequences and for identifying and reconstructing single-chain variable fragments (scFv) and antigen-binding fragments (Fab) not found by conventional ELISA screens. In this work, we developed an NGS-assisted antibody discovery platform by integrating phage-displayed, single-framework, synthetic Fab libraries. Due to limitations in attainable read and amplicon lengths, NGS analysis of Fab libraries and selection outputs is usually restricted to either VH or VL. Since this information alone is not sufficient for high-throughput reconstruction of Fabs, we developed a rapid and simple method for linking and sequencing all diversified CDRs in phage Fab pools. Our method resulted in a reliable and straightforward platform for converting NGS information into Fab clones. We used our NGS-assisted Fab reconstruction method to recover low-frequency rare clones from phage selection outputs. While previous studies chose rare clones for rescue based on their relative frequencies in sequencing outputs, we chose rare clones for reconstruction from less-frequent CDRH3 lengths. In some cases, reconstructed rare clones (frequency ∼0.1%) showed higher affinity and better specificity than high-frequency top clones identified by Sanger sequencing, highlighting the significance of NGS-based approaches in synthetic antibody discovery.
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Affiliation(s)
- Kris Barreto
- Department of Pathology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | | | - Wayne Hill
- Department of Pathology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Daniel Hogan
- Department of Computer Science, University of Saskatchewan, Saskatoon, SK S7N 5C9, Canada
| | - Ashley R Sutherland
- Department of Biochemistry, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - Anthony Kusalik
- Department of Computer Science, University of Saskatchewan, Saskatoon, SK S7N 5C9, Canada
| | - Humphrey Fonge
- Department of Medical Imaging, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - John F DeCoteau
- Department of Pathology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
| | - C Ronald Geyer
- Department of Pathology, University of Saskatchewan, Saskatoon, SK S7N 5E5, Canada
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7
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Barreto K. Depleting the Latent HIV-1 Cell Population using 225Ac-labeled Anti-CD4+ Targeted Radioimmunoconjugates. J Med Imaging Radiat Sci 2019. [DOI: 10.1016/j.jmir.2019.03.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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8
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Hartimath SV, El-Sayed A, Makhlouf A, Bernhard W, Gonzalez C, Hill W, Parada AC, Barreto K, Geyer CR, Fonge H. Therapeutic potential of nimotuzumab PEGylated-maytansine antibody drug conjugates against EGFR positive xenograft. Oncotarget 2019; 10:1031-1044. [PMID: 30800216 PMCID: PMC6383682 DOI: 10.18632/oncotarget.26613] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [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: 09/07/2018] [Accepted: 12/20/2018] [Indexed: 12/26/2022] Open
Abstract
Nimotuzumab is a humanized anti-epidermal growth factor receptor I (EGFR) monoclonal antibody. We have developed antibody drug conjugates (ADCs) with nimotuzumab conjugated to PEGylated-maytansine (PEG6-DM1). We generated conjugates with low (nimotuzumab-PEG6-DM1-Low: DAR = 3.5) and high (nimotuzumab-PEG6-DM1-High: DAR = 7.3) drug to antibody ratios (DAR). Quality control was performed using UV spectrophotometry, size exclusion HPLC, bioanalyzer, biolayer interferometry (BLI), and flow cytometry in EGFR-positive DLD-1, MDA-MB-468 (high density EGFR), and HT-29 (very low EGFR density) cells. Control antibody drug conjugates were developed using a human anti-maltose binding protein (MBP) antibody. BLI showed that the binding of nimotuzumab-PEG6-DM1-Low and nimotuzumab-PEG6-DM1-High was slightly but significantly affected by conjugation of the drug (nimotuzumab KD 0.89 ± 0.02 nM < nimotuzumab-PEG6-DM1-Low KD 1.94 ± 0.02 nM < nimotuzumab-PEG6-DM1-High KD 3.75 ± 0.03 nM). In vitro cytotoxicity was determined following incubation of cells with the immunoconjugates and IC50 values were determined. Nimotuzumab-PEG6-DM1-Low and nimotuzumab-PEG6-DM1-High were used to treat EGFR positive KRAS mutant DLD-1 colorectal cancer xenograft. DLD-1 cells were transduced with a red fluorescent protein (iRFP702) to allow the use of near infrared imaging (NIR) for tumor response monitoring. In vitro potency correlated with the number of drugs on antibody, with nimotuzumab-PEG6-DM1-High showing higher activity than nimotuzumab-PEG6-DM1-Low. Three doses (15 mg/kg) of the ADCs prolonged the survival of DLD-1-iRFP-702 tumor bearing mice as monitored by NIR. Nimotuzumab-PEG6-DM1-Low resulted in 4/6 complete cure while nimotuzumab-PEG6-DM1-High resulted in 2/5 complete cure. The novel ADCs were very effective in a colorectal cancer model in vivo.
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Affiliation(s)
- Siddesh V Hartimath
- Department of Medical Imaging, College of Medicine, University of Saskatchewan, Saskatoon SK, S7N 0W8, Canada.,Saskatchewan Centre for Cyclotron Sciences (SCCS), the Fedoruk Centre, Saskatoon SK, S7N 5C4, Canada
| | - Ayman El-Sayed
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon SK, S7N 5E5, Canada
| | - Amal Makhlouf
- Department of Medical Imaging, College of Medicine, University of Saskatchewan, Saskatoon SK, S7N 0W8, Canada.,Saskatchewan Centre for Cyclotron Sciences (SCCS), the Fedoruk Centre, Saskatoon SK, S7N 5C4, Canada.,Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Cairo University, Kasr El-Aini, 12411, Cairo, Egypt
| | - Wendy Bernhard
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon SK, S7N 5E5, Canada
| | - Carolina Gonzalez
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon SK, S7N 5E5, Canada
| | - Wayne Hill
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon SK, S7N 5E5, Canada
| | | | - Kris Barreto
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon SK, S7N 5E5, Canada
| | - Clarence Ronald Geyer
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Saskatoon SK, S7N 5E5, Canada
| | - Humphrey Fonge
- Department of Medical Imaging, College of Medicine, University of Saskatchewan, Saskatoon SK, S7N 0W8, Canada.,Saskatchewan Centre for Cyclotron Sciences (SCCS), the Fedoruk Centre, Saskatoon SK, S7N 5C4, Canada.,Department of Medical Imaging, Royal University Hospital Saskatoon, Saskatoon SK, S7N 0W8, Canada
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9
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Bernhard W, El-Sayed A, Barreto K, Gonzalez C, Fonge H, Geyer CR. Near infrared imaging of epidermal growth factor receptor positive xenografts in mice with domain I/II specific antibody fragments. Theranostics 2019; 9:974-985. [PMID: 30867810 PMCID: PMC6401412 DOI: 10.7150/thno.30835] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Accepted: 12/31/2018] [Indexed: 12/03/2022] Open
Abstract
Epidermal growth factor receptor (EGFR) is a transmembrane cell surface receptor that is frequently overexpressed and/or mutated in many cancers. Therapies targeting EGFR have poor outcomes due to the lack of reliable diagnostic tests to monitor EGFR. Current in vitro EGFR diagnostic methods are invasive, requiring biopsies, which limits tumor sampling and availability. EGFR molecular imaging provides non-invasive whole-body images capable of detecting primary tumors and metastases, which can be used to diagnose and monitor response to therapy. Methods: We evaluated properties of two anti-EGFR fragments, 8708 and 8709, as molecular-targeted imaging probes. 8708 and 8709 are anti-EGFR antigen binding fragments (Fabs) that recognize domain I/II of EGFR, which is distinct from epitopes recognized by current anti-EGFR therapeutic antibodies. We used complementarity determining region sequences from 8708 and 8709 Fabs to generate an anti-EGFR IgG and (scFv)2 and scFv-Fc antibody fragments. We expressed, purified, and labeled the IgG and fragments with IRDye800CW and used them to image EGFR-positive and -negative xenografts in CD-1 nude mice. 8709 scFv-Fc was also tested for competitive binding with the therapeutic anti-EGFR antibody nimotuzumab and for quantifying ratios of EGFR and EGFRvIII deletion mutant. Results: IRDye800CW-labeled 8708 (scFv)2 and 8709 scFv-Fc imaging probes showed high levels of accumulation and good retention in EGFR-positive xenografts, with peak accumulation occurring at 24 and 48 hours post injection, respectively. IRDye680RD-labeled 8709 scFv-Fc did not compete with IRDye800CW-labeled nimotuzumab for EGFR binding as assayed by flow cytometry using an EGFR-positive cell line. IRDye680RD-labeled 8709 scFv-Fc and IRDye800CW-labeled nimotuzumab used in combination were able to determine the ratio of cells expressing EGFR and a deletion mutant EGFRvIII. Conclusion: IRDye800CW-labeled 8708 (scFv)2 and 8709 scFv-Fc had desirable binding affinities, clearance times, and tumor accumulation to be used for imaging in combination with current EGFR targeted therapies. This study highlights the potential for using 8708 (scFv)2 and 8709 scFv-Fc as EGFR diagnostic and therapy monitoring tools.
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Affiliation(s)
- Wendy Bernhard
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Ayman El-Sayed
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Kris Barreto
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Carolina Gonzalez
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Humphrey Fonge
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
- Saskatchewan Centre for Cyclotron Sciences (SCCS), the Fedoruk Centre, Saskatoon SK, Canada
- Department of Medical Imaging, Royal University Hospital Saskatoon, Saskatoon SK, Canada
| | - Clarence Ronald Geyer
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
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10
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Hashemi P, Barreto K, Bernhard W, Lomness A, Honson N, Pfeifer TA, Harrigan PR, Sadowski I. Compounds producing an effective combinatorial regimen for disruption of HIV-1 latency. EMBO Mol Med 2019; 10:160-174. [PMID: 29246970 PMCID: PMC5838563 DOI: 10.15252/emmm.201708193] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [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] [Indexed: 01/01/2023] Open
Abstract
Highly active antiretroviral therapy (HAART) has improved the outlook for the HIV epidemic, but does not provide a cure. The proposed “shock‐and‐kill” strategy is directed at inducing latent HIV reservoirs, which may then be purged via boosted immune response or targeting infected cells. We describe five novel compounds that are capable of reversing HIV latency without affecting the general T‐cell activation state. The new compounds exhibit synergy for reactivation of latent provirus with other latency‐reversing agents (LRAs), in particular ingenol‐3‐angelate/PEP005. One compound, designated PH02, was efficient at reactivating viral transcription in several cell lines bearing reporter HIV‐1 at different integration sites. Furthermore, it was capable of reversing latency in resting CD4+ T lymphocytes from latently infected aviremic patient cells on HAART, while producing minimal cellular toxicity. The combination of PH02 and PEP005 produces a strong synergistic effect for reactivation, as demonstrated through a quantitative viral outgrowth assay (qVOA), on CD4+ T lymphocytes from HIV‐1‐infected individuals. We propose that the PH02/PEP005 combination may represent an effective novel treatment for abrogating persistent HIV‐1 infection.
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Affiliation(s)
- Pargol Hashemi
- Biochemistry and Molecular Biology, Molecular Epigenetics, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Kris Barreto
- Biochemistry and Molecular Biology, Molecular Epigenetics, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Wendy Bernhard
- Biochemistry and Molecular Biology, Molecular Epigenetics, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Adam Lomness
- Biochemistry and Molecular Biology, Molecular Epigenetics, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Nicolette Honson
- The Centre for Drug Research and Development, Vancouver, BC, Canada
| | - Tom A Pfeifer
- The Centre for Drug Research and Development, Vancouver, BC, Canada
| | - P Richard Harrigan
- BC Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, BC, Canada
| | - Ivan Sadowski
- Biochemistry and Molecular Biology, Molecular Epigenetics, Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
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11
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Hartimath SV, Alizadeh E, Solomon VR, Chekol R, Bernhard W, Hill W, Parada AC, Barreto K, Geyer CR, Fonge H. Preclinical Evaluation of 111In-Labeled PEGylated Maytansine Nimotuzumab Drug Conjugates in EGFR-Positive Cancer Models. J Nucl Med 2019; 60:1103-1110. [PMID: 30655327 DOI: 10.2967/jnumed.118.220095] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [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: 09/05/2018] [Accepted: 12/10/2018] [Indexed: 12/12/2022] Open
Abstract
Epidermal growth factor receptor I (EGFR) is overexpressed in most cancers of epithelial origin. Antibody drug conjugates (ADCs) with PEGylated-maytansine (PEG-DM1) show promise in vitro and in vivo. However, in vivo biodistribution data for ADCs with PEG-DM1 have not been reported. Development of methods to understand the real-time in vivo behavior of these ADCs is needed to move these compounds to the clinic. Methods: Here we have used noninvasive small-animal SPECT/CT imaging and ex vivo biodistribution to understand the in vivo behavior of PEG6-DM1 ADCs. We developed nimotuzumab ADCs conjugated to PEG6-DM1. We generated immunoconjugates with low (nimotuzumab-PEG6-DM1-Low) and high (nimotuzumab-PEG6-DM1-High) drug-to-antibody ratios. The drug-to-antibody of nimotuzumab-PEG6-DM1-Low and nimotuzumab-PEG6-DM1-High was 3.5 and 7.3, respectively. Quality control was performed using ultraviolet spectrophotometry, size-exclusion high-performance liquid chromatography, bioanalyzer, biolayer interferometry, and flow cytometry in EGFR-positive DLD-1 cells. These immunoconjugates were conjugated with DOTA and radiolabeled with 111In. The in vitro binding and internalization rates of 111In-nimotuzumab, 111In-nimotuzumab-PEG6-DM1-Low, and 111In-nimotuzumab-PEG6-DM1-High were characterized. Furthermore, the pharmacokinetics, biodistribution, and imaging characteristics were evaluated in normal and DLD-1 tumor-bearing mice. Results: Flow cytometry and biolayer interferometry showed a trend toward decreasing EGFR affinity with increasing number of PEG6-DM1 on the antibody. Despite the lower overall cellular binding of the PEG6-DM1 radioimmunoconjugates, internalization was higher for PEG6-DM1 ADCs than for the non-PEGylated ADC in the following order: 111In-nimotuzumab-PEG6-DM1-High > 111In-nimotuzumab-PEG6-DM1-Low > 111In-nimotuzumab. Nuclear uptake of 111In-nimotuzumab-PEG6-DM1-High was 4.4-fold higher than 111In-nimotuzumab. Pharmacokinetics and biodistribution showed that 111In-nimotuzumab-PEG6-DM1-High had the slowest blood and whole-body clearance rate. Uptake in DLD-1 tumors of 111In-nimotuzumab was similar to 111In-nimotuzumab-PEG6-DM1-Low but was significantly higher than for 111In-nimotuzumab-PEG6-DM1-High. Tumor-to-background ratios for 111In-nimotuzumab and 111In-nimotuzumab-PEG6-DM1-Low were higher than for 111In-nimotuzumab-PEG6-DM1-High. Conclusion: The results show that conjugation of multiple PEG6-DM1 reduces the affinity for EGFR in vitro. However, the reduced affinity is counteracted by the high internalization rate of constructs with PEG6-DM1 ADCs in vitro. The decreased affinity resulted in low tumor uptake of 111In-nimotuzumab-PEG6-DM1-High, with a slow overall whole-body clearance rate. These data provide insights for evaluating the pharmacokinetics and normal -tissue toxicity and in determining dosing rate of PEGylated ADCs.
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Affiliation(s)
- Siddesh V Hartimath
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Elahe Alizadeh
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Viswas Raja Solomon
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Rufael Chekol
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Wendy Bernhard
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Wayne Hill
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | | | - Kris Barreto
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Clarence Ronald Geyer
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada
| | - Humphrey Fonge
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon SK, Canada .,Department of Medical Imaging, Royal University Hospital (RUH), Saskatoon SK, Canada
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12
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Alam MK, Brabant M, Viswas RS, Barreto K, Fonge H, Ronald Geyer C. A novel synthetic trivalent single chain variable fragment (tri-scFv) construction platform based on the SpyTag/SpyCatcher protein ligase system. BMC Biotechnol 2018; 18:55. [PMID: 30200951 PMCID: PMC6131909 DOI: 10.1186/s12896-018-0466-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [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: 06/15/2018] [Accepted: 09/03/2018] [Indexed: 01/12/2023] Open
Abstract
Background Advances in antibody engineering provide strategies to construct recombinant antibody-like molecules with modified pharmacokinetic properties. Multermerization is one strategy that has been used to produce antibody-like molecules with two or more antigen binding sites. Multimerization enhances the functional affinity (avidity) and can be used to optimize size and pharmacokinetic properties. Most multimerization strategies involve genetically fusing or non-covalently linking antibody fragments using oligomerization domains. Recent studies have defined guidelines for producing antibody-like molecules with optimal tumor targeting properties, which require intermediates size (70–120 kDa) and bi- or tri-valency. Results We described a highly modular antibody-engineering platform for rapidly constructing synthetic, trivalent single chain variable fragments (Tri-scFv) using the SpyCatcher/SpyTag protein ligase system. We used this platform to construct an anti-human epidermal growth factor receptor 3 (HER3) Tri-scFv. We generated the anti-HER3 Tri-scFv by genetically fusing a SpyCatcher to the C-terminus of an anti-HER3 scFv and ligating it to a synthetic Tri-SpyTag peptide. The anti-HER3 Tri-scFv bound recombinant HER3 with an apparent KD of 2.67 nM, which is approximately 12 times lower than the KD of monomeric anti-HER3 scFv (31.2 nM). Anti-HER3 Tri-scFv also bound endogenous cell surface expressed HER3 stronger than the monomer anti-HER3 scFv. Conclusion We used the SpyTag/SpyCatcher protein ligase system to ligate anti-HER3 scFv fused to a SpyCatcher at its C-termini to a Tri-SpyTag to construct Tr-scFv. This system allowed the construction of a Tri-scFv with all the scFv antigen-binding sites pointed outwards. The anti-HER3 Tri-scFv bound recombinant and endogenously expressed HER3 with higher functional affinity (avidity) than the monomeric anti-HER3 scFv. The Tri-scFv had the size, valency, and functional affinity that are desired for therapeutic and imaging applications. Use of the SpyTag/SpyCatcher protein ligase system allows Tri-scFvs to be rapidly constructed in a simple, modular manner, which can be easily applied to scFvs or other antibody fragments targeting other antigens.
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Affiliation(s)
- Md Kausar Alam
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Room 2841, Royal University Hospital, 103 Hospital Drive, Saskatoon, S7N 0W8, Canada
| | - Michelle Brabant
- Department of Biochemistry, College of Medicine, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada
| | | | - Kris Barreto
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Room 2841, Royal University Hospital, 103 Hospital Drive, Saskatoon, S7N 0W8, Canada
| | - Humphrey Fonge
- Medical Imaging, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada
| | - C Ronald Geyer
- Department of Pathology and Laboratory Medicine, College of Medicine, University of Saskatchewan, Room 2841, Royal University Hospital, 103 Hospital Drive, Saskatoon, S7N 0W8, Canada.
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El-Sayed A, Bernhard W, Barreto K, Gonzalez C, Hill W, Pastushok L, Fonge H, Geyer CR. Evaluation of antibody fragment properties for near-infrared fluorescence imaging of HER3-positive cancer xenografts. Am J Cancer Res 2018; 8:4856-4869. [PMID: 30279742 PMCID: PMC6160764 DOI: 10.7150/thno.24252] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 07/10/2018] [Indexed: 11/24/2022] Open
Abstract
In vivo imaging is influenced by the half-life, tissue penetration, biodistribution, and affinity of the imaging probe. Immunoglobulin G (IgG) is composed of discrete domains with known functions, providing a template for engineering antibody fragments with desired imaging properties. Here, we engineered antibody-based imaging probes, consisting of different combinations of antibody domains, labeled them with the near-infrared fluorescent dye IRDye800CW, and evaluated their in vivo imaging properties. Antibody-based imaging probes were based on an anti-HER3 antigen binding fragment (Fab) isolated using phage display. Methods: We constructed six anti-HER3 antibody-based imaging probes: a single chain variable fragment (scFv), Fab, diabody, scFv-CH3, scFv-Fc, and IgG. IRDye800CW-labeled, antibody-based probes were injected into nude mice bearing FaDu xenografts and their distribution to the xenograft, liver, and kidneys was evaluated. Results: These imaging probes bound to recombinant HER3 and to the HER3-positive cell line, FaDu. Small antibody fragments with molecular weight <60 kDa (scFv, diabody, and Fab) accumulated rapidly in the xenograft (maximum accumulation between 2-4 h post injection (hpi)) and cleared primarily through the kidneys. scFv-CH3 (80 kDa) had fast clearance and peaked in the xenograft between 2-3 hpi and cleared from xenograft in a rate comparable to Fab and diabody. IgG and scFv-Fc persisted in the xenografts for up to 72 hpi and distributed mainly to the xenograft and liver. The highest xenograft fluorescence signals were observed with IgG and scFv-Fc imaging probes and persisted for 2-3 days. Conclusion: These results highlight the utility of using antibody fragments to optimize clearance, tumor labeling, and biodistribution properties for developing anti-HER3 probes for image-guided surgery or PET imaging.
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14
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Solomon VR, Gonzalez C, Alizadeh E, Bernhard W, Hartimath SV, Barreto K, Geyer CR, Fonge H. 99mTc(CO) 3+ labeled domain I/II-specific anti-EGFR (scFv) 2 antibody fragment for imaging EGFR expression. Eur J Med Chem 2018; 157:437-446. [PMID: 30103192 DOI: 10.1016/j.ejmech.2018.08.014] [Citation(s) in RCA: 8] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2018] [Revised: 07/31/2018] [Accepted: 08/04/2018] [Indexed: 12/17/2022]
Abstract
Bifunctional chelators (BFCs) are covalently linked to biologically active targeting molecules and radiolabeled with radiometals. Technetium-99 m (99mTc) is the most widely used isotope in nuclear medicine because of its excellent physical properties. The objective of this study was to synthesize and characterize a novel BFC that allows for the labeling of antibodies and antibody fragments using the 99mTc(CO)3+ core which forms a very stable complex with 99mTc in the +1 oxidation sate. This study reports the synthesis of a BFC 1-pyrrolidinyl-2,5-dione-11-(bis((1-(carboxymethyl)-1H-imidazol-2-yl)methyl)amino)undecanoic acid (SAAC-CIM NHS ester), and the in vitro and in vivo evaluation of 99mTc(CO)3-SAAC-CIM-DLO6-(scFv)2 (99mTc(CO)3-DLO6-(scFv)2), a domain I/II-specific anti-epidermal growth factor receptor I (anti-EGFR) antibody fragment. The chelator allowed radiolabeling the (scFv)2 antibody fragment in very mild conditions with no significant decrease in binding to EGFR. Radiochemical yields of >50% (radiochemical purity > 95%) of the resulting anti-EGFR (scFv)2 immunoconjugate 99mTc(CO)3-DLO6-(scFv)2 was obtained. The radioimmunoconjugate was stable in histidine challenge experiments with less than 20% transchelation at 24 h after challenge in the presence of a 1500-fold excess of histidine. In vivo biodistribution of 99mTc(CO)3-DLO6-(scFv)2 indicates that the tracer was mainly cleared via renal excretion and to a lesser extent via the hepatobiliary pathway. The microSPECT imaging studies performed in mice confirmed the in vitro affinity results. The 99mTc(CO)3-DLO6-(scFv)2 shows some promising properties and warrants further investigation for imaging EGFR.
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Affiliation(s)
- Viswas Raja Solomon
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada; Saskatchewan Centre for Cyclotron Sciences (SCCS), The Fedoruk Centre, Saskatoon, SK, Canada
| | - Carolina Gonzalez
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Elahe Alizadeh
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada; Saskatchewan Centre for Cyclotron Sciences (SCCS), The Fedoruk Centre, Saskatoon, SK, Canada
| | - Wendy Bernhard
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Siddesh V Hartimath
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada; Saskatchewan Centre for Cyclotron Sciences (SCCS), The Fedoruk Centre, Saskatoon, SK, Canada
| | - Kris Barreto
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Clarence Ronald Geyer
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada.
| | - Humphrey Fonge
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada; Saskatchewan Centre for Cyclotron Sciences (SCCS), The Fedoruk Centre, Saskatoon, SK, Canada; Department of Medical Imaging, Royal University Hospital Saskatoon, Saskatoon, SK, Canada.
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15
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Chekol R, Solomon VR, Alizadeh E, Bernhard W, Fisher D, Hill W, Barreto K, DeCoteau JF, Parada AC, Geyer CR, Fonge H. 89Zr-nimotuzumab for immunoPET imaging of epidermal growth factor receptor I. Oncotarget 2018; 9:17117-17132. [PMID: 29682209 PMCID: PMC5908310 DOI: 10.18632/oncotarget.24965] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [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: 01/08/2018] [Accepted: 02/26/2018] [Indexed: 11/25/2022] Open
Abstract
Rationale Epidermal growth factor receptor (EGFR) upregulation is associated with enhanced proliferation and drug resistance in a number of cancers. Nimotuzumab is a humanized monoclonal antibody with high affinity for EGFR. The objective of this study was to determine if 89Zr-DFO-nimotuzumab could be suitable for human use as a PET probe for quantifying EGFR in vivo. Methods To evaluate the pharmacokinetics, biodistribution, microPET imaging, radiation dosimetry, and normal tissue toxicity in tumor and non-tumor bearing mice of 89Zr-desferoxamine-nimotuzumab (89Zr-DFO-nimotuzumab) of a product prepared under GMP conditions. Nimotuzumab was conjugated to DFO and radiolabeled with 89Zr. 89Zr-DFO-nimotuzumab was characterized by in vitro gel-electrophoresis, biolayer interferometry (BLI) and flow cytometry. 89Zr-DFO-nimotuzumab was evaluated in vivo by microPET and ex vivo by biodistribution in healthy and EGFR-positive tumor bearing mice. Results Flow cytometry with A431 cells showed no significant difference in the dissociation constant of nimotuzumab (13 ± 2 nM) compared with DFO-nimotuzumab (17 ± 4 nM). PET imaging in mice xenografts showed persistently high tumor uptake with the highest uptake obtained in DLD-1 xenograft (18.3 %IA/cc) at 168 hp.i. The projected human effective dose was low and was 0.184 mSv/MBq (0.679 rem/mCi) in females and 0.205 mSv/MBq (0.757 rem/mCi) in males. There was no apparent normal tissue toxicity as shown by cell blood counts and blood biochemistry analyses at 168-fold and 25-fold excess of the projected human radioactive and mass dose of the agent. Conclusion 89Zr-DFO-nimotuzumab had low organ absorbed dose and effective dose that makes it suitable for potential human use.
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Affiliation(s)
- Rufael Chekol
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada.,Saskatchewan Centre for Cyclotron Sciences (SCCS), The Fedoruk Centre, Saskatoon, SK, Canada
| | - Viswas Raja Solomon
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada.,Saskatchewan Centre for Cyclotron Sciences (SCCS), The Fedoruk Centre, Saskatoon, SK, Canada
| | - Elahe Alizadeh
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada.,Saskatchewan Centre for Cyclotron Sciences (SCCS), The Fedoruk Centre, Saskatoon, SK, Canada
| | - Wendy Bernhard
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Darrell Fisher
- Versant Medical Physics and Radiation Safety, Boston, MA, USA
| | - Wayne Hill
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Kris Barreto
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - John Francis DeCoteau
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | | | - Clarence Ronald Geyer
- Department of Pathology and Laboratory Medicine, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada
| | - Humphrey Fonge
- Department of Medical Imaging, University of Saskatchewan, College of Medicine, Saskatoon, SK, Canada.,Saskatchewan Centre for Cyclotron Sciences (SCCS), The Fedoruk Centre, Saskatoon, SK, Canada.,Department of Medical Imaging, Royal University Hospital Saskatoon, Saskatoon, SK, Canada
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Bernhard W, El-Sayed A, Barreto K, Gonzalez C, Hill W, Parada AC, Fonge H, Geyer CR. Near infrared fluorescence imaging of EGFR expression in vivo using IRDye800CW-nimotuzumab. Oncotarget 2017; 9:6213-6227. [PMID: 29464066 PMCID: PMC5814206 DOI: 10.18632/oncotarget.23557] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [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: 08/25/2017] [Accepted: 10/27/2017] [Indexed: 01/24/2023] Open
Abstract
Nimotuzumab is a humanized anti-epidermal growth factor receptor (EGFR) monoclonal antibody that is approved in many countries for the treatment of EGFR-positive cancers. Near infrared (NIR) fluorescent dye-labeled antibodies represent an attractive class of image-guided surgical probes because of their high specificity, tumor uptake, and low dissociation from tumor cells that express the antigen. In this study, we developed a NIR fluorescent dye-labeled nimotuzumab immunoconjugate, IRDye800CW-nimotuzumab, and evaluated in vitro binding with EGFR-positive cells, in vivo tumor uptake by NIR fluorescent imaging, and ex vivo biodistribution. There was no difference in binding between nimotuzumab and IRDye800CW-nimotuzumab to EGFR-positive cells. In mice bearing EGFR-positive xenografts, IRDye800CW-nimotuzumab uptake peaked at 4 days post injection and slowly decreased thereafter with high levels of accumulation still observed at 28 days post injection. In EGFR-positive xenografts, IRDye800CW-nimotuzumab showed more than 2-fold higher uptake in tumors compared to IRDye800CW-cetuximab. In addition, liver uptake of IRDye800CW-nimotuzumab was two-fold lower than cetuximab. The lower liver uptake of IRDye800CW-nimotuzumab could have implications on the selected dose for clinical trials of the immunoconjugate. In summary, this study shows that nimotuzumab is a good candidate for NIR fluorescent imaging and image-guided surgery.
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Affiliation(s)
- Wendy Bernhard
- Department of Pathology, University of Saskatchewan, Saskatoon, Canada
| | - Ayman El-Sayed
- Department of Pathology, University of Saskatchewan, Saskatoon, Canada
| | - Kris Barreto
- Department of Pathology, University of Saskatchewan, Saskatoon, Canada
| | - Carolina Gonzalez
- Department of Pathology, University of Saskatchewan, Saskatoon, Canada
| | - Wayne Hill
- Department of Pathology, University of Saskatchewan, Saskatoon, Canada
| | | | - Humphrey Fonge
- Department of Medical Imaging, University of Saskatchewan, Saskatoon, Canada.,Department of Medical Imaging, Royal University Hospital, Saskatoon, Canada.,Saskatchewan Centre for Cyclotron Sciences (SCCS), Fedoruk Centre, Saskatoon, Canada
| | - C Ronald Geyer
- Department of Pathology, University of Saskatchewan, Saskatoon, Canada
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17
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Alam MK, Gonzalez C, Hill W, El-Sayed A, Fonge H, Barreto K, Geyer CR. Cover Feature: Synthetic Modular Antibody Construction by Using the SpyTag/SpyCatcher Protein-Ligase System (ChemBioChem 22/2017). Chembiochem 2017. [DOI: 10.1002/cbic.201700569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Md Kausar Alam
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Carolina Gonzalez
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Wayne Hill
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Ayman El-Sayed
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Humphrey Fonge
- Medical Imaging; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Kris Barreto
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - C. Ronald Geyer
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
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Maruthachalam BV, El-Sayed A, Liu J, Sutherland AR, Hill W, Alam MK, Pastushok L, Fonge H, Barreto K, Geyer CR. A Single-Framework Synthetic Antibody Library Containing a Combination of Canonical and Variable Complementarity-Determining Regions. Chembiochem 2017; 18:2247-2259. [DOI: 10.1002/cbic.201700279] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Indexed: 12/21/2022]
Affiliation(s)
| | - Ayman El-Sayed
- Department of Pathology; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Jianghai Liu
- Department of Pathology; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Ashley R. Sutherland
- Department of Biochemistry; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Wayne Hill
- Department of Pathology; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Md Kausar Alam
- Department of Pathology; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Landon Pastushok
- Department of Pathology; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Humphrey Fonge
- Department of Medical Imaging; University of Saskatchewan; Saskatoon SK S7N 0W8 Canada
| | - Kris Barreto
- Department of Pathology; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - C. Ronald Geyer
- Department of Pathology; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
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Alam MK, Gonzalez C, Hill W, El-Sayed A, Fonge H, Barreto K, Geyer CR. Synthetic Modular Antibody Construction by Using the SpyTag/SpyCatcher Protein-Ligase System. Chembiochem 2017; 18:2217-2221. [DOI: 10.1002/cbic.201700411] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Indexed: 12/18/2022]
Affiliation(s)
- Md Kausar Alam
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Carolina Gonzalez
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Wayne Hill
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Ayman El-Sayed
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Humphrey Fonge
- Medical Imaging; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - Kris Barreto
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
| | - C. Ronald Geyer
- Department of Pathology and Laboratory Medicine; University of Saskatchewan; Saskatoon SK S7N 5E5 Canada
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Abstract
Peptides are useful reagents for reverse analysis of protein function in a variety of organisms, as they have a dominant mode of action that can inhibit protein interactions or activities. Further, peptides are important tools for validating proteins as therapeutic targets, for determining structure/activity relationships, and for designing small molecules. Genetic selection strategies have been developed for screening combinatorial peptide libraries to rapidly isolate peptides that interact with a given target. In genetic selections and biological assays, linear peptides are not very stable and are rapidly degraded. In contrast, cyclic peptides are more stable and bind with higher affinity. Genetic selections of cyclic peptides are difficult as they are not compatible with most selection technologies. Thus, there has been limited number of applications that use cyclic peptides for the reverse analysis of protein function.Here, we describe a protocol to isolate cyclic peptides that bind proteins in the yeast two-hybrid assay. Cyclic peptides used in the yeast two-hybrid assay are referred to as "lariat" peptides. Lariat peptides are made by blocking the intein-producing cyclic peptide reaction at an intermediate step. They consist of a lactone cyclic peptide or "noose" region connected by an amide bond to a transcription activation domain. Combinatorial libraries of >10(7) lariat peptides can be screened using the yeast two-hybrid assay to isolate lariat peptides for studying the function or validating the therapeutic potential of protein targets.
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Affiliation(s)
- Kris Barreto
- Department of Biochemistry, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK, Canada, S7N 5E5
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21
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Bernhard W, Barreto K, Raithatha S, Sadowski I. An upstream YY1 binding site on the HIV-1 LTR contributes to latent infection. PLoS One 2013; 8:e77052. [PMID: 24116200 PMCID: PMC3792934 DOI: 10.1371/journal.pone.0077052] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [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: 08/02/2013] [Accepted: 08/28/2013] [Indexed: 02/03/2023] Open
Abstract
During HIV-1 infection a population of latently infected cells is established. This population is the major obstacle preventing total eradication of the virus from AIDS patients. HIV-1 latency is thought to arise by various mechanisms including repressive chromatin modifications. Transcription factors such as YY1 have been shown to facilitate repressive chromatin modifications by the recruitment of histone deacetylases. In this study, we identified a novel binding site for YY1 on the HIV-1 LTR, 120 nucleotides upstream of the transcription start site. We show that YY1 can bind to this site in vitro and in vivo and that binding to the LTR is dissociated upon T cell activation. Overexpression of YY1 causes an increase in the proportion of cells that produce latent infections. These observations, in combination with previous results, demonstrate that YY1 plays a prominent role in controlling the establishment and maintenance of latent HIV-1 provirus in unstimulated cells.
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Affiliation(s)
- Wendy Bernhard
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kris Barreto
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Sheetal Raithatha
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Ivan Sadowski
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
- * E-mail:
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22
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Abstract
Going against tradition: although most kinase inhibitors are ATP competitive, lariat peptides inhibit Abl kinase activity in an ATP-uncompetitive manner. Further, lariat peptides discriminated Src family kinases, and recognize the allosteric region that lies adjacent to the ATP binding pocket in the Abl kinase catalytic cleft.
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Affiliation(s)
- V M Bharathikumar
- Department of Biochemistry, University of Saskatchewan, 107 Wiggins Road, Saskatoon, SK S7N 5E5 (Canada)
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23
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Sadowski I, Breitkreutz BJ, Stark C, Su TC, Dahabieh M, Raithatha S, Bernhard W, Oughtred R, Dolinski K, Barreto K, Tyers M. The PhosphoGRID Saccharomyces cerevisiae protein phosphorylation site database: version 2.0 update. Database (Oxford) 2013; 2013:bat026. [PMID: 23674503 PMCID: PMC3653121 DOI: 10.1093/database/bat026] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
PhosphoGRID is an online database that curates and houses experimentally verified in vivo phosphorylation sites in the Saccharomyces cerevisiae proteome (www.phosphogrid.org). Phosphosites are annotated with specific protein kinases and/or phosphatases, along with the condition(s) under which the phosphorylation occurs and/or the effects on protein function. We report here an updated data set, including nine additional high-throughput (HTP) mass spectrometry studies. The version 2.0 data set contains information on 20 177 unique phosphorylated residues, representing a 4-fold increase from version 1.0, and includes 1614 unique phosphosites derived from focused low-throughput (LTP) studies. The overlap between HTP and LTP studies represents only ∼3% of the total unique sites, but importantly 45% of sites from LTP studies with defined function were discovered in at least two independent HTP studies. The majority of new phosphosites in this update occur on previously documented proteins, suggesting that coverage of phosphoproteins in the yeast proteome is approaching saturation. We will continue to update the PhosphoGRID data set, with the expectation that the integration of information from LTP and HTP studies will enable the development of predictive models of phosphorylation-based signaling networks. Database URL:http://www.phosphogrid.org/
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Affiliation(s)
- Ivan Sadowski
- Department of Biochemistry and Molecular Biology, Molecular Epigenetics, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia, Canada V6T 1Z3.
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24
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Barreto K, Aparicio A, Bharathikumar VM, DeCoteau JF, Geyer CR. Yeast two-hybrid screening of cyclic peptide libraries using a combination of random and PI-deconvolution pooling strategies. Protein Eng Des Sel 2012; 25:453-64. [PMID: 22763264 DOI: 10.1093/protein/gzs029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We developed a high throughput yeast two-hybrid (Y2H) assay for screening pools of combinatorial cyclic peptide preys against pools of bait proteins. The assay used the PI (pooling with imaginary tags) deconvolution pooling strategy to generate pools of baits and a random pooling strategy to generate pools of cyclic peptide preys. Haploid yeast, expressing pools of baits or preys, were arrayed and mated to each other to generate diploid arrays, where the yeast express both baits and preys. Diploid arrays were scored for activation of the Y2H reporter genes. We used this Y2H pooling strategy, referred to as 'PI-pool-on-random pool', to screen a cyclic peptide library for interactions against Bcr-Abl domains. Seven Bcr-Abl domain baits and LexA control were pooled using the PI deconvolution pooling strategy. The cyclic peptide library was randomly arrayed into pools of ~1000 members. Cyclic peptides were isolated for six of seven Bcr-Abl domain baits. The PI-pool-on-random pooling Y2H assay using high stringency Y2H reporter genes produced no false positives, while missing 20% of real interactions. The high specificity of the PI-pool-on-random pooling Y2H assay eliminates the need to validate interactions. Pooling of baits and preys allows large prey libraries to be screened against multiple baits and takes advantage of PI-deconvolution to determine protein interactions with high sensitivity and specificity. The scalability of this assay allows the peptide preys to be isolated in a high throughput manner against a large number of baits and provides an avenue for generating affinity agents against entire proteomes in the future.
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Affiliation(s)
- K Barreto
- Department of Biochemistry, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E5
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25
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Bernhard W, Barreto K, Saunders A, Dahabieh MS, Johnson P, Sadowski I. The Suv39H1 methyltransferase inhibitor chaetocin causes induction of integrated HIV-1 without producing a T cell response. FEBS Lett 2011; 585:3549-54. [PMID: 22020221 DOI: 10.1016/j.febslet.2011.10.018] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 10/05/2011] [Accepted: 10/07/2011] [Indexed: 12/18/2022]
Abstract
Latent HIV-1 (human immunodeficiency virus-1) provirus is unaffected by current AIDS (acquired immunodeficiency syndrome) therapies. We show here that chaetocin, an SUV39H1 histone methyltransferase inhibitor, causes 25-fold induction of latent HIV-1 expression, while producing minimal toxicity and without causing T cell activation. Induction is associated with loss of histone H3 lysine 9 (H3K9) trimethylation at the long terminal repeat (LTR) promoter, and a corresponding increase in H3K9 acetylation. The effect of chaetocin is amplified synergistically in combination with histone deacetylase (HDAC) inhibitors. These results indicate that chaetocin may provide a therapy to purge cells of latent HIV-1, possibly in combination with other chromatin remodeling drugs.
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Affiliation(s)
- Wendy Bernhard
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, Canada
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Barreto K, Bharathikumar VM, Ricardo A, DeCoteau JF, Luo Y, Geyer CR. A genetic screen for isolating "lariat" Peptide inhibitors of protein function. ACTA ACUST UNITED AC 2010; 16:1148-57. [PMID: 19942138 DOI: 10.1016/j.chembiol.2009.10.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2009] [Revised: 09/30/2009] [Accepted: 10/19/2009] [Indexed: 10/20/2022]
Abstract
Functional genomic analyses provide information that allows hypotheses to be formulated on protein function. These hypotheses, however, need to be validated using reverse genetic approaches, which are difficult to perform on a large scale and in diploid organisms. We developed a genetic screen for isolating "lariat" peptides that function as trans dominant inhibitors of protein function. A lariat consists of a lactone-cyclized peptide with a covalently attached transcription activation domain, which allows combinatorial lariat libraries to be screened for protein interactions using the yeast two-hybrid assay. We isolated lariats against the bacterial repressor protein LexA. LexA regulates bacterial SOS response and LexA mutants that cannot undergo autoproteolysis make bacteria more sensitive to, and inhibit resistance against, cytotoxic reagents. We showed that an anti-LexA lariat blocked LexA autoproteolysis and potentiated the antimicrobial activity of mitomycin C.
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