1
|
Ge S, Dias ACP, Zhang X. Chimerism of avian IgY-scFv and truncated IgG-Fc: A novel strategy in cross-species antibody generation and enhancement. Immunology 2024; 172:46-60. [PMID: 38247105 DOI: 10.1111/imm.13752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2023] [Accepted: 12/15/2023] [Indexed: 01/23/2024] Open
Abstract
Chicken single-chain fragment variable (IgY-scFv) is a functional fragment and an emerging development in genetically engineered antibodies with a wide range of biomedical applications. However, scFvs have considerably shorter serum half-life due to the absence of antibody Fc region compared with the full-length antibody, and usually requires continuous intravenous administration for efficacy. A promising approach to overcome this limitation is to fuse scFv with immunoglobulin G (IgG) Fc region, for better recognition and mediation by the neonatal Fc receptor (FcRn) in the host. In this study, engineered mammalian ΔFc domains (CH2, CH3, and intact Fc region) were fused with anti-canine parvovirus-like particles avian IgY-scFv to produce chimeric antibodies and expressed in the HEK293 cell expression system. The obtained scFv-CH2, scFv-CH3, and scFv-Fc can bind with antigen specifically and dose-dependently. Surface plasmon resonance investigation confirmed that scFv-CH2, scFv-CH3, and scFv-Fc had different degrees of binding to FcRn, with scFv-Fc showing the highest affinity. scFv-Fc had a significantly longer half-life in mice compared with the unfused scFv. The identified ΔFcs are promising for the development of engineered Fc-based therapeutic antibodies and proteins with longer half-lives. The avian IgY-scFv-mammalian IgG Fc region opens up new avenues for antibody engineering, and it is a novel strategy to enhance the rapid development and screening of functional antibodies in veterinary and human medicine.
Collapse
Affiliation(s)
- Shikun Ge
- Department of Biology, Centre of Molecular and Environmental Biology, University of Minho, Braga, Portugal
- College of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, China
| | - Alberto Carlos Pires Dias
- Department of Biology, Centre of Molecular and Environmental Biology, University of Minho, Braga, Portugal
| | - Xiaoying Zhang
- Department of Biology, Centre of Molecular and Environmental Biology, University of Minho, Braga, Portugal
- College of Biological Science and Engineering, Shaanxi University of Technology, Hanzhong, China
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph, Ontario, Canada
| |
Collapse
|
2
|
Awad RM, Breckpot K. Novel technologies for applying immune checkpoint blockers. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2023; 382:1-101. [PMID: 38225100 DOI: 10.1016/bs.ircmb.2023.03.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
Abstract
Cancer cells develop several ways to subdue the immune system among others via upregulation of inhibitory immune checkpoint (ICP) proteins. These ICPs paralyze immune effector cells and thereby enable unfettered tumor growth. Monoclonal antibodies (mAbs) that block ICPs can prevent immune exhaustion. Due to their outstanding effects, mAbs revolutionized the field of cancer immunotherapy. However, current ICP therapy regimens suffer from issues related to systemic administration of mAbs, including the onset of immune related adverse events, poor pharmacokinetics, limited tumor accessibility and immunogenicity. These drawbacks and new insights on spatiality prompted the exploration of novel administration routes for mAbs for instance peritumoral delivery. Moreover, novel ICP drug classes that are adept to novel delivery technologies were developed to circumvent the drawbacks of mAbs. We therefore review the state-of-the-art and novel delivery strategies of ICP drugs.
Collapse
Affiliation(s)
- Robin Maximilian Awad
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Karine Breckpot
- Laboratory for Molecular and Cellular Therapy, Department of Biomedical Sciences, Vrije Universiteit Brussel, Brussels, Belgium.
| |
Collapse
|
3
|
Baart VM, van Manen L, Bhairosingh SS, Vuijk FA, Iamele L, de Jonge H, Scotti C, Resnati M, Cordfunke RA, Kuppen PJK, Mazar AP, Burggraaf J, Vahrmeijer AL, Sier CFM. Side-by-Side Comparison of uPAR-Targeting Optical Imaging Antibodies and Antibody Fragments for Fluorescence-Guided Surgery of Solid Tumors. Mol Imaging Biol 2023; 25:122-132. [PMID: 34642899 PMCID: PMC9970952 DOI: 10.1007/s11307-021-01657-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 08/27/2021] [Accepted: 09/21/2021] [Indexed: 01/22/2023]
Abstract
PURPOSE Radical resection is paramount for curative oncological surgery. Fluorescence-guided surgery (FGS) aids in intraoperative identification of tumor-positive resection margins. This study aims to assess the feasibility of urokinase plasminogen activator receptor (uPAR) targeting antibody fragments for FGS in a direct comparison with their parent IgG in various relevant in vivo models. PROCEDURES Humanized anti-uPAR monoclonal antibody MNPR-101 (uIgG) was proteolytically digested into F(ab')2 and Fab fragments named uFab2 and uFab. Surface plasmon resonance (SPR) and cell assays were used to determine in vitro binding before and after fluorescent labeling with IRDye800CW. Mice bearing subcutaneous HT-29 human colonic cancer cells were imaged serially for up to 120 h after fluorescent tracer administration. Imaging characteristics and ex vivo organ biodistribution were further compared in orthotopic pancreatic ductal adenocarcinoma (BxPc-3-luc2), head-and-neck squamous cell carcinoma (OSC-19-luc2-GFP), and peritoneal carcinomatosis (HT29-luc2) models using the clinical Artemis fluorescence imaging system. RESULTS Unconjugated and conjugated uIgG, uFab2, and uFab specifically recognized uPAR in the nanomolar range as determined by SPR and cell assays. Subcutaneous tumors were clearly identifiable with tumor-to-background ratios (TBRs) > 2 after 72 h for uIgG-800F and 24 h for uFab2-800F and uFab-800F. For the latter two, mean fluorescence intensities (MFIs) dipped below predetermined threshold after 72 h and 36 h, respectively. Tumors were easily identified in the orthotopic models with uIgG-800F consistently having the highest MFIs and uFab2-800F and uFab-800F having similar values. In biodistribution studies, kidney and liver fluorescence approached tumor fluorescence after uIgG-800F administration and surpassed tumor fluorescence after uFab2-800F or uFab-800F administration, resulting in interference in the abdominal orthotopic mouse models. CONCLUSIONS In a side-by-side comparison, FGS with uPAR-targeting antibody fragments compared with the parent IgG resulted in earlier tumor visualization at the expense of peak fluorescence intensity.
Collapse
Affiliation(s)
- Victor M Baart
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands.
| | - Labrinus van Manen
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Floris A Vuijk
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | - Luisa Iamele
- Unit of Immunology and General Pathology, Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Ardis Srl, Pavia, Italy
| | - Hugo de Jonge
- Unit of Immunology and General Pathology, Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Ardis Srl, Pavia, Italy
| | - Claudia Scotti
- Unit of Immunology and General Pathology, Department of Molecular Medicine, University of Pavia, Pavia, Italy.,Ardis Srl, Pavia, Italy
| | - Massimo Resnati
- Age Related Diseases Unit, Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milano, Italy
| | - Robert A Cordfunke
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Peter J K Kuppen
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Jacobus Burggraaf
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands.,Centre for Human Drug Research, Leiden, The Netherlands
| | | | - Cornelis F M Sier
- Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands.,Percuros BV, Leiden, The Netherlands
| |
Collapse
|
4
|
Tran VL, Bouleau A, Nozach H, Richard M, Chevaleyre C, Dubois S, Kereselidze D, Kuhnast B, Evans MJ, Specklin S, Truillet C. Impact of Radiolabeling Strategies on the Pharmacokinetics and Distribution of an Anti-PD-L1 PET Ligand. Mol Pharm 2022; 19:3673-3680. [PMID: 35998011 DOI: 10.1021/acs.molpharmaceut.2c00497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Molecular imaging with PET offers an alternative method to quantify programmed-death-ligand 1 (PD-L1) to accurately select patients for immunotherapies. More and more clinical and preclinical trials involve radiolabeling of antibody fragments for their desirably fast clearance and high tumor penetration. As the radiolabeling strategy can significantly impact pharmacokinetics and biodistribution, we explored in this work a site-specific radiofluorination strategy on an anti-PD-L1 fragment antigen-binding (Fab) and compared the pharmacokinetic and biodistribution properties with the same Fab labeled using stochastic radiolabeling chemistry. We applied an enzymatic bioconjugation mediated by a variant of the lipoic acid ligase (LplA) that promotes the formation of an amide bond between a short peptide cloned onto the C terminus of the Fab. A synthetic analogue of the enzyme natural substrate, lipoic acid, was radiolabeled with fluorine-18 for site-specific conjugation by LplA. We compared the biodistribution of the site-specifically labeled Fab with a stochastically labeled Fab on lysine side chains in tumor-bearing mice. The two methods of fluorination demonstrate a comparable whole-body biodistribution. The 89Zr-labeled Fab had different biodistribution compared to either 18F-labeled Fab. We attribute the difference to [89Zr] metabolism. Fab-LAP-[18F]FPyOctA therefore reflects better the true pharmacokinetic profile of the Fab.
Collapse
Affiliation(s)
- Vu Long Tran
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, SHFJ, Orsay 91400, France
| | - Alizée Bouleau
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, SHFJ, Orsay 91400, France
| | - Hervé Nozach
- Université Paris-Saclay, CEA, DMTS, SIMoS, CEA-Saclay, Gif-sur-Yvette CEDEX 91191, France
| | - Mylène Richard
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, SHFJ, Orsay 91400, France
| | - Céline Chevaleyre
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, SHFJ, Orsay 91400, France
| | - Steven Dubois
- Université Paris-Saclay, CEA, DMTS, SIMoS, CEA-Saclay, Gif-sur-Yvette CEDEX 91191, France
| | - Dimitri Kereselidze
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, SHFJ, Orsay 91400, France
| | - Bertrand Kuhnast
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, SHFJ, Orsay 91400, France
| | - Michael J Evans
- Department of Radiology and Biomedical Imaging, UCSF, San Francisco, California 94107, United States
| | - Simon Specklin
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, SHFJ, Orsay 91400, France
| | - Charles Truillet
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, SHFJ, Orsay 91400, France
| |
Collapse
|
5
|
Near-Infrared Fluorescence Imaging of EGFR-Overexpressing Tumors in the Mouse Xenograft Model Using scFv-IRDye800CW and Cetuximab-IRDye800CW. Mol Imaging 2022; 2022:9589820. [PMID: 35517713 PMCID: PMC9042373 DOI: 10.1155/2022/9589820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Accepted: 03/21/2022] [Indexed: 12/18/2022] Open
Abstract
EGFR (epidermal growth factor receptor) is overexpressed in a variety of human cancers (including squamous cell carcinoma of head and neck, colon cancer, and some breast cancers) and therefore is regarded as an ideal target for cancer therapy or imaging purposes. In the current study, we produced a scFv-based near-infrared probe (called cet.Hum.scFv-IRDye-800CW) and evaluated its ability in recognizing and imaging of EGFR-overexpressing tumors in a mouse model. Like the molecular probe consisting of its parental antibody (cetuximab, an FDA-approved monoclonal antibody) and IRD800CW, cet.Hum.scFv-IRDye-800CW was able to recognize EGFR-overexpressing tumors in mice. cet.Hum.scFv-IRDye-800CW was found to be superior to the cetuximab-based probe in imaging of mouse tumors. The tumor-to-background ratio and blood clearance rate were higher when cet.Hum.scFv-IRDye-800CW was used as an imaging probe.
Collapse
|
6
|
Imaging Immune Cells Using Fc Domain Probes in Mouse Cancer Xenograft Models. Cancers (Basel) 2022; 14:cancers14020300. [PMID: 35053466 PMCID: PMC8773629 DOI: 10.3390/cancers14020300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 12/31/2021] [Accepted: 01/05/2022] [Indexed: 02/04/2023] Open
Abstract
Simple Summary The immune system responds to abnormal cell growth by sending immune cells to kill them. The immune cell response is very important since it can usually stop abnormal cells from growing and spreading. Immuno-therapeutics used to treat cancer require help from the immune system to be effective. A biopsy is typically performed to determine the therapeutic efficacy of cancer treatment which is invasive and difficult. A simpler and less invasive way to monitor therapeutic efficacy is needed. Here, we show a molecule that can be used as an imaging agent to determine immune cell recruitment to tumors. Abstract Tracking immune responses is complex due to the mixture of cell types, variability in cell populations, and the dynamic environment. Tissue biopsies and blood analysis can identify infiltrating and circulating immune cells; however, due to the dynamic nature of the immune response, these are prone to sampling errors. Non-invasive targeted molecular imaging provides a method to monitor immune response, which has advantages of providing whole-body images, being non-invasive, and allowing longitudinal monitoring. Three non-specific Fc-containing proteins were labeled with near-infrared dye IRDye800CW and used as imaging probes to assess tumor-infiltrating immune cells in FaDu and A-431 xenograft models. We showed that Fc domains localize to tumors and are visible by fluorescent imaging. This tumor localization appears to be based on binding tumor-associated immune cells and some xenografts showed higher fluorescent signals than others. The Fc domain alone bound to different human immune cell types. The Fc domain can be a valuable research tool to study innate immune response.
Collapse
|
7
|
Fundamentals and developments in fluorescence-guided cancer surgery. Nat Rev Clin Oncol 2022; 19:9-22. [PMID: 34493858 DOI: 10.1038/s41571-021-00548-3] [Citation(s) in RCA: 93] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/26/2021] [Indexed: 02/07/2023]
Abstract
Fluorescence-guided surgery using tumour-targeted imaging agents has emerged over the past decade as a promising and effective method of intraoperative cancer detection. An impressive number of fluorescently labelled antibodies, peptides, particles and other molecules related to cancer hallmarks have been developed for the illumination of target lesions. New approaches are being implemented to translate these imaging agents into the clinic, although only a few have made it past early-phase clinical trials. For this translational process to succeed, target selection, imaging agents and their related detection systems and clinical implementation have to operate in perfect harmony to enable real-time intraoperative visualization that can benefit patients. Herein, we review key aspects of this imaging cascade and focus on imaging approaches and methods that have helped to shed new light onto the field of intraoperative fluorescence-guided cancer surgery with the singular goal of improving patient outcomes.
Collapse
|
8
|
Wang W, Wang J, Hong G, Mao L, Zhu N, Liu T. Methoxypolyethylene Glycol-Substituted Zinc Phthalocyanines for Multiple Tumor-Selective Fluorescence Imaging and Photodynamic Therapy. Biomacromolecules 2021; 22:4284-4294. [PMID: 34569232 DOI: 10.1021/acs.biomac.1c00855] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Highly tumor-tissue-selective drugs are a prerequisite for accurate diagnosis and efficient photodynamic therapy (PDT) of tumors, but the currently used fluorescent dyes and photosensitizers generally lack the ability for high accumulation and precise localization in tumor tissues. Here we report that monomethoxy polyethylene glycol (MPEG)-modified zinc phthalocyanine (ZnPc) can be selectively accumulated in multiple tumor tissues, and that the selectivity is controlled by the chain length of MPEG. MPEG-monosubstituted ZnPcs with different chain lengths were synthesized, among which the shorter chain (mw < 2k)-modified ZnPc did not show tumor tissue selectivity, while MPEG2k-5k-substituted ZnPc could be rapidly and selectively accumulated in H22 tumor tissues in mice after intravenous injection. Especially, MPEG4k-Pc showed the best tumor tissue selectivity with a tumor/liver (T/L) ratio of 1.7-2.2 in HepG2, MDA-MB231, AGS, and HT-29 tumor-bearing mice. It also exhibited potent photodynamic therapy effects after one PDT treatment, and tumor growth was significantly inhibited in H22-bearing mice with an inhibition rate over 98% and no obvious toxicity. Consequently, MPEG-modified ZnPc could serve as a potential platform for selective fluorescence imaging and photodynamic therapy of multiple tumors.
Collapse
Affiliation(s)
- Wenzhi Wang
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, China
| | - Jiawen Wang
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, China
| | - Ge Hong
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, China
| | - Lina Mao
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, China
| | - Na Zhu
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, China
| | - Tianjun Liu
- Tianjin Key Laboratory of Biomedical Materials, Institute of Biomedical Engineering, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300192, China
| |
Collapse
|
9
|
Ahmadi P, Muguruma K, Chang TC, Tamura S, Tsubokura K, Egawa Y, Suzuki T, Dohmae N, Nakao Y, Tanaka K. In vivo metal-catalyzed SeCT therapy by a proapoptotic peptide. Chem Sci 2021; 12:12266-12273. [PMID: 34603656 PMCID: PMC8480321 DOI: 10.1039/d1sc01784e] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 08/16/2021] [Indexed: 01/03/2023] Open
Abstract
Selective cell tagging (SeCT) therapy is a strategy for labeling a targeted cell with certain chemical moieties via a catalytic chemical transformation in order to elicit a therapeutic effect. Herein, we report a cancer therapy based on targeted cell surface tagging with proapoptotic peptides (Ac-GGKLFG-X; X = reactive group) that induce apoptosis when attached to the cell surface. Using either Au-catalyzed amidation or Ru-catalyzed alkylation, these proapoptotic peptides showed excellent therapeutic effects both in vitro and in vivo. In particular, co-treatment with proapoptotic peptide and the carrier-Ru complex significantly and synergistically inhibited tumor growth and prolonged survival rate of tumor-bearing mice after only a single injection. This is the first report of Ru catalyst application in vivo, and this approach could be used in SeCT for cancer therapy.
Collapse
Affiliation(s)
- Peni Ahmadi
- Biofunctional Synthetic Chemistry, RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Kyohei Muguruma
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology 2-12-1 Ookayama Meguro Tokyo 152-8552 Japan
| | - Tsung-Che Chang
- Biofunctional Synthetic Chemistry, RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Satoru Tamura
- Department of Medicinal and Organic Chemistry, School of Pharmacy, Iwate Medical University Yahaba Iwate 028-3694 Japan
| | - Kazuki Tsubokura
- Biofunctional Synthetic Chemistry, RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Yasuko Egawa
- Biofunctional Synthetic Chemistry, RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Takehiro Suzuki
- Biomolecular Characterization Unit, RIKEN Center for Sustainable Resource Science 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Naoshi Dohmae
- Biomolecular Characterization Unit, RIKEN Center for Sustainable Resource Science 2-1 Hirosawa Wako Saitama 351-0198 Japan
| | - Yoichi Nakao
- School of Advanced Science and Engineering, Department of Chemistry and Biochemistry, Waseda University 3-4-1 Okubo Shinjuku Tokyo 169-8555 Japan
| | - Katsunori Tanaka
- Biofunctional Synthetic Chemistry, RIKEN Cluster for Pioneering Research 2-1 Hirosawa Wako Saitama 351-0198 Japan
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology, Tokyo Institute of Technology 2-12-1 Ookayama Meguro Tokyo 152-8552 Japan
- Biofunctional Chemistry Laboratory, A. Butlerov Institute of Chemistry, Kazan Federal University 18 Kremlyovskaya Street Kazan 420008 Russia
| |
Collapse
|
10
|
Meng B, Folaron MR, Strawbridge RR, Sadeghipour N, Samkoe KS, Tichauer K, Davis SC. Noninvasive quantification of target availability during therapy using paired-agent fluorescence tomography. Am J Cancer Res 2020; 10:11230-11243. [PMID: 33042280 PMCID: PMC7532673 DOI: 10.7150/thno.45273] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 08/06/2020] [Indexed: 12/13/2022] Open
Abstract
Immuno-oncological treatment strategies that target abnormal receptor profiles of tumors are an increasingly important feature of cancer therapy. Yet, assessing receptor availability (RA) and drug-target engagement, important determinants of therapeutic efficacy, is challenging with current imaging strategies, largely due to the complex nonspecific uptake behavior of imaging agents in tumors. Herein, we evaluate whether a quantitative noninvasive imaging approach designed to compensate for nonspecific uptake, MRI-coupled paired-agent fluorescence tomography (MRI-PAFT), is capable of rapidly assessing the availability of epidermal growth factor receptor (EGFR) in response to one dose of anti-EGFR antibody therapy in orthotopic brain tumor models. Methods: Mice bearing orthotopic brain tumor xenografts with relatively high EGFR expression (U251) (N=10) or undetectable human EGFR (9L) (N=9) were considered in this study. For each tumor type, mice were either treated with one dose of cetuximab, or remained untreated. All animals were scanned using MRI-PAFT, which commenced immediately after paired-agent administration, and values of RA were recovered using a model-based approach, which uses the entire dynamic sequence of agent uptake, as well as a simplified “snapshot” approach which requires uptake measurements at only two time points. Recovered values of RA were evaluated between groups and techniques. Hematoxylin & eosin (H&E) and immunohistochemical (IHC) staining was performed on tumor specimens from every animal to confirm tumor presence and EGFR status. Results: In animals bearing EGFR(+) tumors, a significant difference in RA values between treated and untreated animals was observed (RA = 0.24 ± 0.15 and 0.61 ± 0.18, respectively, p=0.027), with an area under the curve - receiver operating characteristic (AUC-ROC) value of 0.92. We did not observe a statistically significant difference in RA values between treated and untreated animals bearing EGFR(-) tumors (RA = 0.18 ± 0.19 and 0.27 ± 0.21, respectively; p = 0.89; AUC-ROC = 0.55), nor did we observe a difference between treated EGFR(+) tumors compared to treated and untreated EGFR(-) tumors. Notably, the snapshot paired-agent strategy quantified drug-receptor engagement within just 30 minutes of agent administration. Examination of the targeted agent alone showed no capacity to distinguish tumors either by treatment or receptor status, even 24h after agent administration. Conclusions: This study demonstrated that a noninvasive imaging strategy enables rapid quantification of receptor availability in response to therapy, a capability that could be leveraged in preclinical drug development, patient stratification, and treatment monitoring.
Collapse
|
11
|
Engineered Fragments of the PSMA-Specific 5D3 Antibody and Their Functional Characterization. Int J Mol Sci 2020; 21:ijms21186672. [PMID: 32932591 PMCID: PMC7555429 DOI: 10.3390/ijms21186672] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 11/29/2022] Open
Abstract
Prostate-Specific Membrane Antigen (PSMA) is an established biomarker for the imaging and experimental therapy of prostate cancer (PCa), as it is strongly upregulated in high-grade primary, androgen-independent, and metastatic lesions. Here, we report on the development and functional characterization of recombinant single-chain Fv (scFv) and Fab fragments derived from the 5D3 PSMA-specific monoclonal antibody (mAb). These fragments were engineered, heterologously expressed in insect S2 cells, and purified to homogeneity with yields up to 20 mg/L. In vitro assays including ELISA, immunofluorescence and flow cytometry, revealed that the fragments retain the nanomolar affinity and single target specificity of the parent 5D3 antibody. Importantly, using a murine xenograft model of PCa, we verified the suitability of fluorescently labeled fragments for in vivo imaging of PSMA-positive tumors and compared their pharmacokinetics and tissue distribution to the parent mAb. Collectively, our data provide an experimental basis for the further development of 5D3 recombinant fragments for future clinical use.
Collapse
|
12
|
Hanna R, Cardarelli L, Patel N, Blazer LL, Adams JJ, Sidhu SS. A phage-displayed single-chain Fab library optimized for rapid production of single-chain IgGs. Protein Sci 2020; 29:2075-2084. [PMID: 32803886 DOI: 10.1002/pro.3931] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 08/10/2020] [Accepted: 08/11/2020] [Indexed: 12/25/2022]
Abstract
Phage-displayed synthetic antibody (Ab) repertoires have become a major source of affinity reagents for basic and clinical research. Specific Abs identified from such libraries are often screened as fragments antigen binding (Fabs) produced in bacteria, and those with desired biochemical characteristics are reformatted for production as full-length immunoglobulin G (IgG) in mammalian cells. The conversion of Fabs to IgGs is a cumbersome and often rate-limiting step in the development of Abs. Moreover, biochemical properties required for lead IgG development are not always shared by the Fabs, and these issues are not uncovered until a significant effort has been spent on Abs that ultimately will not be useful. Thus, there is a need for simple and rapid techniques to convert phage-displayed Fabs to IgGs at an early stage of the Ab screening process. We report the generation of a highly diverse phage-displayed synthetic single-chain Fab (scFab) library, in which the light and heavy chains were tethered with an optimized linker. Following selection, pools of scFabs were converted to single-chain IgGs (scIgGs) en masse, enabling facile screening of hundreds of phage-derived scIgGs. We show that this approach can be used to rapidly screen for and select scIgGs that target cell-surface receptors, and scIgGs behave the same as conventional IgGs.
Collapse
Affiliation(s)
- Rachel Hanna
- Department of Molecular Genetics, Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Lia Cardarelli
- Department of Molecular Genetics, Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Nish Patel
- Department of Molecular Genetics, Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Levi L Blazer
- Department of Molecular Genetics, Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Jarrett J Adams
- Department of Molecular Genetics, Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| | - Sachdev S Sidhu
- Department of Molecular Genetics, Donnelly Centre, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
13
|
Wu Y, Zhang F. Exploiting molecular probes to perform near‐infrared fluorescence‐guided surgery. VIEW 2020. [DOI: 10.1002/viw.20200068] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Yifan Wu
- Department of Chemistry State Key Laboratory of Molecular Engineering of Polymers Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials and iChem Fudan University Shanghai China
| | - Fan Zhang
- Department of Chemistry State Key Laboratory of Molecular Engineering of Polymers Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials and iChem Fudan University Shanghai China
| |
Collapse
|
14
|
Cnudde T, Lakhrif Z, Bourgoin J, Boursin F, Horiot C, Henriquet C, di Tommaso A, Juste MO, Jiacomini IG, Dimier-Poisson I, Pugnière M, Mévélec MN, Aubrey N. Exploration and Modulation of Antibody Fragment Biophysical Properties by Replacing the Framework Region Sequences. Antibodies (Basel) 2020; 9:antib9020009. [PMID: 32326443 PMCID: PMC7344962 DOI: 10.3390/antib9020009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 04/12/2020] [Accepted: 04/13/2020] [Indexed: 02/06/2023] Open
Abstract
In order to increase the successful development of recombinant antibodies and fragments, it seems fundamental to enhance their expression and/or biophysical properties, such as the thermal, chemical, and pH stabilities. In this study, we employed a method bases on replacing the antibody framework region sequences, in order to promote more particularly single-chain Fragment variable (scFv) product quality. We provide evidence that mutations of the VH- C-C′ loop might significantly improve the prokaryote production of well-folded and functional fragments with a production yield multiplied by 27 times. Additional mutations are accountable for an increase in the thermal (+19.6 °C) and chemical (+1.9 M) stabilities have also been identified. Furthermore, the hereby-produced fragments have shown to remain stable at a pH of 2.0, which avoids molecule functional and structural impairments during the purification process. Lastly, this study provides relevant information to the understanding of the relationship between the antibodies amino acid sequences and their respective biophysical properties.
Collapse
Affiliation(s)
- Thomas Cnudde
- INRAE, ISP, Université de Tours, F-37000 Tours, France; (T.C.); (Z.L.)
| | - Zineb Lakhrif
- INRAE, ISP, Université de Tours, F-37000 Tours, France; (T.C.); (Z.L.)
| | - Justine Bourgoin
- INRAE, ISP, Université de Tours, F-37000 Tours, France; (T.C.); (Z.L.)
| | - Fanny Boursin
- INRAE, ISP, Université de Tours, F-37000 Tours, France; (T.C.); (Z.L.)
| | - Catherine Horiot
- INRAE, ISP, Université de Tours, F-37000 Tours, France; (T.C.); (Z.L.)
| | - Corinne Henriquet
- IRCM, Institut de Recherche en Cancérologie de Montpellier, INSERM, U1194, Université Montpellier, ICM Institut Régional du Cancer, 34090 Montpellier, France
| | - Anne di Tommaso
- INRAE, ISP, Université de Tours, F-37000 Tours, France; (T.C.); (Z.L.)
| | | | - Isabella Gizzi Jiacomini
- Laboratório de Imunoquímica, Departamento de Patologia Básica, Universidade Federal do Paraná, Curitiba 81530, PR, Brazil
| | | | - Martine Pugnière
- IRCM, Institut de Recherche en Cancérologie de Montpellier, INSERM, U1194, Université Montpellier, ICM Institut Régional du Cancer, 34090 Montpellier, France
| | | | - Nicolas Aubrey
- INRAE, ISP, Université de Tours, F-37000 Tours, France; (T.C.); (Z.L.)
- Correspondence:
| |
Collapse
|
15
|
Wei W, Rosenkrans ZT, Liu J, Huang G, Luo QY, Cai W. ImmunoPET: Concept, Design, and Applications. Chem Rev 2020; 120:3787-3851. [PMID: 32202104 DOI: 10.1021/acs.chemrev.9b00738] [Citation(s) in RCA: 224] [Impact Index Per Article: 56.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Immuno-positron emission tomography (immunoPET) is a paradigm-shifting molecular imaging modality combining the superior targeting specificity of monoclonal antibody (mAb) and the inherent sensitivity of PET technique. A variety of radionuclides and mAbs have been exploited to develop immunoPET probes, which has been driven by the development and optimization of radiochemistry and conjugation strategies. In addition, tumor-targeting vectors with a short circulation time (e.g., Nanobody) or with an enhanced binding affinity (e.g., bispecific antibody) are being used to design novel immunoPET probes. Accordingly, several immunoPET probes, such as 89Zr-Df-pertuzumab and 89Zr-atezolizumab, have been successfully translated for clinical use. By noninvasively and dynamically revealing the expression of heterogeneous tumor antigens, immunoPET imaging is gradually changing the theranostic landscape of several types of malignancies. ImmunoPET is the method of choice for imaging specific tumor markers, immune cells, immune checkpoints, and inflammatory processes. Furthermore, the integration of immunoPET imaging in antibody drug development is of substantial significance because it provides pivotal information regarding antibody targeting abilities and distribution profiles. Herein, we present the latest immunoPET imaging strategies and their preclinical and clinical applications. We also emphasize current conjugation strategies that can be leveraged to develop next-generation immunoPET probes. Lastly, we discuss practical considerations to tune the development and translation of immunoPET imaging strategies.
Collapse
Affiliation(s)
- Weijun Wei
- Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.,Departments of Radiology and Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Room 7137, Madison, Wisconsin 53705, United States
| | - Zachary T Rosenkrans
- Department of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States
| | - Jianjun Liu
- Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Gang Huang
- Department of Nuclear Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.,Shanghai Key Laboratory of Molecular Imaging, Shanghai University of Medicine and Health Sciences, Shanghai 201318, China
| | - Quan-Yong Luo
- Department of Nuclear Medicine, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai 200233, China
| | - Weibo Cai
- Departments of Radiology and Medical Physics, University of Wisconsin-Madison, 1111 Highland Avenue, Room 7137, Madison, Wisconsin 53705, United States.,Department of Pharmaceutical Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53705, United States.,University of Wisconsin Carbone Cancer Center, Madison, Wisconsin 53705, United States
| |
Collapse
|
16
|
Zhao X, Ning Q, Mo Z, Tang S. A promising cancer diagnosis and treatment strategy: targeted cancer therapy and imaging based on antibody fragment. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2020; 47:3621-3630. [PMID: 31468992 DOI: 10.1080/21691401.2019.1657875] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
With the arrival of the precision medicine and personalized treatment era, targeted therapy that improves efficacy and reduces side effects has become the mainstream approach of cancer treatment. Antibody fragments that further enhance penetration and retain the most critical antigen-specific binding functions are considered the focus of research targeting cancer imaging and therapy. Thanks to the superior penetration and rapid blood clearance of antibody fragments, antibody fragment-based imaging agents enable efficient and sensitive imaging of tumour sites. In tumour-targeted therapy, antibody fragments can directly inhibit tumour proliferation and growth, serve as an ideal carrier for delivery of anti-tumour drugs, or manipulate the immune system to eliminate tumour cells. In this review, the excellent physicochemical properties and the basic structure of antibody fragments are expressly depicted depicted, the progress of antibody fragments in cancer therapy and imaging are thoroughly summarized, and the future development of antibody fragments is predicted.
Collapse
Affiliation(s)
- Xuhong Zhao
- Learning Key Laboratory for Pharmacoproteomics of Hunan Province, Institute of Pharmacy and Pharmacology, University of South China , Hengyang , China.,Hunan Province Key Laboratory for Antibody-Based Drug and Intelligent Delivery System, Hunan University of Medicine , Huaihua , China
| | - Qian Ning
- Hunan Province Key Laboratory for Antibody-Based Drug and Intelligent Delivery System, Hunan University of Medicine , Huaihua , China
| | - Zhongcheng Mo
- Department of Histology and Embryology, Clinical Anatomy and Reproductive Medicine Application Institute, Hengyang Medical School, University of South China , Hengyang , China
| | - Shengsong Tang
- Learning Key Laboratory for Pharmacoproteomics of Hunan Province, Institute of Pharmacy and Pharmacology, University of South China , Hengyang , China.,Hunan Province Key Laboratory for Antibody-Based Drug and Intelligent Delivery System, Hunan University of Medicine , Huaihua , China
| |
Collapse
|
17
|
Xing J, Wang Z, Xu H, Liu C, Wei Z, Zhao L, Ren L. Pak2 inhibition promotes resveratrol-mediated glioblastoma A172 cell apoptosis via modulating the AMPK-YAP signaling pathway. J Cell Physiol 2020; 235:6563-6573. [PMID: 32017068 DOI: 10.1002/jcp.29515] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Accepted: 01/08/2020] [Indexed: 12/28/2022]
Abstract
As a polyphenolic compound, resveratrol (Res) is widely present in a variety of plants. Previous studies have shown that Res can inhibit various tumors. However, its role in c remains largely unexplored. In the present study, we first demonstrated that Res inhibited cell viability and induced apoptosis of glioblastoma A172 cell. Further experiments showed that Res induced mitochondrial dysfunction and activated the activity of caspase-9. Functional studies have found that Res treatment is associated with an increase in the expression of Pak2. Interestingly, inhibition of Pak2 could further augment the proapoptotic effect of Res. Mechanistically, Pak2 inhibition induced reactive oxygen species overproduction, mitochondria-JNK pathway activation, and AMPK-YAP axis suppression. However, overexpression of YAP could abolish the anticancer effects of Res and Pak2 inhibition, suggesting a necessary role played by the AMPK-YAP pathway in regulating cancer-suppressive actions of Res and Pak2 inhibition. Altogether, our results indicated that Res in combination with Pak2 inhibition could further enhance the anticancer property of Res and this effect is mediated via the AMPK-YAP pathway.
Collapse
Affiliation(s)
- Jin Xing
- Department of Neurosurgery, Shanghai Pudong Hospital, Shanghai Fu Dan University School of Medicine, Shanghai, China
| | - Zhihan Wang
- Department of Neurosurgery, Shanghai Pudong Hospital, Shanghai Fu Dan University School of Medicine, Shanghai, China
| | - Hao Xu
- Department of Neurosurgery, Shanghai Pudong Hospital, Shanghai Fu Dan University School of Medicine, Shanghai, China
| | - Chaobo Liu
- Department of Neurosurgery, Shanghai Pudong Hospital, Shanghai Fu Dan University School of Medicine, Shanghai, China
| | - Zilong Wei
- Department of Neurosurgery, Shanghai Pudong Hospital, Shanghai Fu Dan University School of Medicine, Shanghai, China
| | - Liang Zhao
- Department of Neurosurgery, Shanghai Pudong Hospital, Shanghai Fu Dan University School of Medicine, Shanghai, China
| | - Li Ren
- Department of Neurosurgery, Shanghai Pudong Hospital, Shanghai Fu Dan University School of Medicine, Shanghai, China
| |
Collapse
|
18
|
Debie P, Hernot S. Emerging Fluorescent Molecular Tracers to Guide Intra-Operative Surgical Decision-Making. Front Pharmacol 2019; 10:510. [PMID: 31139085 PMCID: PMC6527780 DOI: 10.3389/fphar.2019.00510] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 04/24/2019] [Indexed: 12/26/2022] Open
Abstract
Fluorescence imaging is an emerging technology that can provide real-time information about the operating field during cancer surgery. Non-specific fluorescent agents, used for the assessment of blood flow and sentinel lymph node detection, have so far dominated this field. However, over the last decade, several clinical studies have demonstrated the great potential of targeted fluorescent tracers to visualize tumor lesions in a more specific way. This has led to an exponential growth in the development of novel molecular fluorescent contrast agents. In this review, the design of fluorescent molecular tracers will be discussed, with particular attention for agents and approaches that are of interest for clinical translation.
Collapse
Affiliation(s)
| | - Sophie Hernot
- Laboratory for in vivo Cellular and Molecular Imaging (ICMI-BEFY/MIMA), Vrije Universiteit Brussel, Brussels, Belgium
| |
Collapse
|
19
|
Liu D, Li W, Jiang X, Bai S, Liu J, Liu X, Shi Y, Kuai Z, Kong W, Gao R, Shan Y. Using near-infrared enhanced thermozyme and scFv dual-conjugated Au nanorods for detection and targeted photothermal treatment of Alzheimer's disease. Theranostics 2019; 9:2268-2281. [PMID: 31149043 PMCID: PMC6531298 DOI: 10.7150/thno.30649] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Accepted: 12/26/2018] [Indexed: 02/06/2023] Open
Abstract
Investigation of targeting inhibitors of Aβ aggregation, heme-Aβ peroxidase-like activity and efficient detectors of Aβ aggregation, are of therapeutic value and diagnostics significance for the treatment of Alzheimer's disease (AD). Due to the complex pathogenesis of AD, theranostics treatment with multiple functions are necessary. Herein we constructed the NIR absorption property of gold nanorods (GNRs) loaded with single chain variable fragment (scFv) 12B4 and thermophilic acylpeptide hydrolase (APH) ST0779 as a smart theranostic complex (GNRs-APH-scFv, GAS), which possesses both rapid detection of Aβ aggregates and NIR photothermal treatment that effectively disassembles Aβ aggregates and inhibits Aβ-mediated toxicity. Methods: We screened targeting anti-Aβ scFv 12B4 and thermophilic acylpeptide hydrolase as amyloid-degrading enzyme, synthesized GAS gold nanorods complex. The GAS was evalued by Aβ inhibition and disaggregation assays, Aβ detection assays, Aβ mediated toxicity assays in vitro. In vivo, delaying Aβ-induced paralysis in AD model of Caenorhabditis elegans was also tested by GAS. Results: In vitro, GAS has a synergistic effect to inhibit and disassociate Aβ aggregates, in addition to decrease heme-Aβ peroxidase-like activity. In cultured cells, treatment with GAS reduces Aβ-induced cytotoxicity, while also delaying Aβ-mediated paralysis in CL4176 C.elegans model of AD. Furthermore, the photothermal effect of the GAS upon NIR laser irradiation not only helps disassociate the Aβ aggregates but also boosts APH activity to clear Aβ. The GAS, as a targeting detector and inhibitor, allows real-time detection of Aβ aggregates. Conclusion: These results firstly highlight the combination of scFv, APH and nanoparticles to be theranostic AD drugs. Taken together, our strategy provides a new thought into the design of smart compounds for use as efficiently therapeutic and preventive agents against AD. Moreover, our design provides broad prospects of biomedical strategy for further theranostics application in those diseases caused by abnormal protein.
Collapse
|
20
|
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] [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.
Collapse
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
| |
Collapse
|