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Singla R, Wall D, Anderson S, Zia N, Korte JC, Kravets L, McKiernan G, Butler J, Gammilonghi A, Arora J, Solomon B, Hicks R, Cain T, Darcy P, Cullinane C, Neeson P, Ramanathan R, Shukla R, Bansal V, Harrison S. Abstract LB-023: Dynamic real time in vivo CAR T cell tracking: Clinical and preclinical studies using a novel dual PET-MR imaging agent. Cancer Res 2020. [DOI: 10.1158/1538-7445.am2020-lb-023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Objective: The aim is to demonstrate dynamic in-vivo tracking of CAR T cell therapy for treatment of solid tumors using Cu-64 labeled superparamagnetic iron oxide nanoparticles (SPION) as novel dual PET-MR imaging agent.
Methodology: Cu-64 SPION: Cu-64 radioisotope is bound to silica coated SPION using enhanced electrolysis plating techniques with tin and palladium seeding. Preclinical Model: Mouse splenic T cells were activated with anti-CD3, anti-CD28 & cultured with IL-2 and IL-7, prior to being transduced with second generation anti-Her-2 CAR (scFv-CD28-CD3ζ). 5 x 105 E0771-hHER2 breast tumor cells were implanted subcutaneously into male C57Bl/6-human HER2 transgenic mice. 107 labeled CAR T or control T cells (Cu-64 5-8 MBq) were injected into tail vein. Clinical Model: Activated T cells using antibody CD3 (OKT3) & IL-2 are transduced with retroviral vector constructs encoding for chimeric T-cell receptor specific for Lewis Y antigen. Modified T-cells are further expanded ex-vivo and reinfused. 3 x 108 CAR T cells were labeled with Cu-64 (200 - 300 MBq). Labeling of CAR T cells with Cu-64 SPION: Transfecting agent protamine sulphate facilitated cellular uptake of Cu-64 SPION within cells. Functional assays: 51Chromium release, cytometric bead array and cell viability showed that labeling process did not affect CAR T cell cytotoxicity, cytokine secretion (TNFα and IFN-γ) and viability. CAR T Cell Tracking: Scanning was performed using clinical grade dual PET-MR scanner.
Preliminary Data: In this clinical trial (HREC/16/PMCC/30) patients are being enrolled for first in human in vivo study to determine how many cells distribute to solid tumor sites within first few days of CAR T cell therapy. This is first data that demonstrates that CAR-T cells can be consistently and efficiently labeled (≤60%) with cell viability (≥85%) and at sensitivity comparable to detecting at least z cells at tumor site using clinical grade dual PET-MR scanner. SUVmean values provides insight into individual response to therapy. The observed increase in SUVmax over time specifies localization of CAR T cells at tumor sites.
Clinical data at early time point showed moderate uptake in lungs posterior basal segments without increased activity over next few days, thus suggesting transient process. Mild, diffuse bone marrow and relatively intense uptake in the liver and spleen suggests margination of cells to the reticulo-endothelial system. Distinct PET signal suggests localization of labeled cells in the secondary tumor sites. Little background uptake in important organs such as brain and heart indicate the safety profile of imaging agent. Absence of signal in bladder indicates hepatobiliary excretion, which may allow re-absorption from GI tract and re-circulation.
Distinct PET signal within tumor in preclinical studies confirms trafficking of CAR T cells to tumor site as compared to controls. A negative contrast in the liver on T2 weighted MRI in both the preclinical and clinical studies. Preliminary Conclusion:This is first in human in vivo study to show CAR T cell distribution in real time and provides insight into individual responses of tumors to therapy. CAR T cell functionality largely remain unchanged due to labeling process. The preliminary findings indicate that labeled cells traffic to tumor sites in first few hours of infusion and remain persistent for extended period.
Citation Format: Ritu Singla, Dominic Wall, Samuel Anderson, Nicholas Zia, James C. Korte, Lucy Kravets, Gerard McKiernan, Jeanne Butler, Amanda Gammilonghi, Jyoti Arora, Ben Solomon, Rodney Hicks, Timothy Cain, Phillip Darcy, Carleen Cullinane, Paul Neeson, Rajesh Ramanathan, Ravi Shukla, Vipul Bansal, Simon Harrison. Dynamic real time in vivo CAR T cell tracking: Clinical and preclinical studies using a novel dual PET-MR imaging agent [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-023.
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Affiliation(s)
- Ritu Singla
- 1Cell Therapies Pty Ltd., MELBOURNE, Australia
| | | | | | | | | | | | | | - Jeanne Butler
- 4Peter MacCallum Cancer Centre, MELBOURNE, Australia
| | | | | | - Ben Solomon
- 4Peter MacCallum Cancer Centre, MELBOURNE, Australia
| | - Rodney Hicks
- 4Peter MacCallum Cancer Centre, MELBOURNE, Australia
| | | | - Phillip Darcy
- 4Peter MacCallum Cancer Centre, MELBOURNE, Australia
| | | | - Paul Neeson
- 4Peter MacCallum Cancer Centre, MELBOURNE, Australia
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Singla R, Wall DM, Anderson S, Zia N, Korte JC, Kravets L, McKiernan G, Butler J, Gammilonghi A, Arora J, Solomon BJ, Hicks RJ, Cain T, Darcy PK, Cullinane C, Neeson PJ, Ramanathan R, Shukla R, Bansal V, Harrison SJ. First in-human study of in vivo imaging of ex vivo labeled CAR T cells with dual PET-MR. J Clin Oncol 2020. [DOI: 10.1200/jco.2020.38.15_suppl.3557] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
3557 Background: This is a first in human in-vivo biodistribution of ex-vivo labelled CAR T cells assessed in a cohort of patients. Cells were labelled with novel Cu-64 labelled superparamagnetic iron oxide nanoparticles (SPION) and infused IV into patients with solid tumors & tracked using clinical dual PET-MR. The study validates the clinical translation of CAR T cell in-vivo tracking in real time. Methods: Cu-64 radioisotope was bound to silica coated SPION using electrolysis plating with tin & palladium seeding. Cellular uptake of Cu-64 SPION was facilitated with a transfecting agent. Functional assays including 51Chromium release, cytometric bead array demonstrated that labelling process did not affect cytotoxicity & cytokine secretion (TNFα & IFN-g). T cells were transduced with retroviral vector constructs encoding for second-generation chimeric T-cell receptor specific for carbohydrate Lewis Y antigen. Modified T-cells were expanded ex-vivo & were labelled with Cu-64 (~300 MBq) prior to re-infusion (3 x108 labelled cells). Scanning is performed with Siemens 3T dual PET-MR scanner. Results: In this first in human in-vivo study (HREC/16/PMCC/30) a cohort of patients received ex-vivo labelled CAR T cells to determine how many labelled cells distribute to solid tumor sites within 3-5 days. Our results demonstrate that cells can be efficiently labelled (≤60%) with high cell viability (≥85%) at a sensitivity sufficient to detect labelled cells at tumor site for up to 5 days. An observed trend in SUVmean & SUVmax provided insight into efficacy & individual response to therapy. Early time points showed moderate uptake of labelled cells in lungs posterior basal segments without increased activity over next few days, suggesting a transient process. Mild, diffuse bone marrow & relatively intense uptake of labelled cells in liver & spleen suggests margination of cells to reticulo-endothelial system. Distinct PET signal at some of the tumor sites at 24 h suggests antigen specific localization & time taken to reach these sites. Excretion via hepatobiliary indicated reabsorption from GI tract & re-circulation of labelled cells. Minimal uptake in brain & heart supported safety profile of labeling agent. Conclusions: This is first in human in-vivo study to provide highly valuable visual and dynamic data in real time and provides insight into individual responses to therapy. CAR T cell functionality largely remain unchanged due to labeling process. The findings indicate that labelled cells traffic to tumor sites at later time points & remain persistent for extended period of time.
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Affiliation(s)
- Ritu Singla
- Cell Therapies, Peter MacCallum Cancer Centre, Melbourne, Australia
| | | | - Samuel Anderson
- Sir Ian Potter NanoBioSensing Facility, RMIT University, Melbourne, Australia
| | | | | | - Lucy Kravets
- Cell Therapies, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Gerard McKiernan
- Cell Therapies, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Jeanne Butler
- Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
| | - Amanda Gammilonghi
- Sir Ian Potter NanoBioSensing Facility, RMIT University, Melbourne, Australia
| | - Jyoti Arora
- Sir Ian Potter NanoBioSensing Facility, RMIT University, Melbourne, Australia
| | | | | | | | - Phillip K. Darcy
- Peter MacCallum Cancer Centre, The University of Melbourne, Melbourne, Australia
| | | | - Paul J. Neeson
- Peter MacCallum Cancer Centre, The University of Melbourne, Melbourne, Australia
| | - Rajesh Ramanathan
- Sir Ian Potter NanoBioSensing Facility, RMIT University, Melbourne, Australia
| | - Ravi Shukla
- Sir Ian Potter NanoBioSensing Facility, RMIT University, Melbourne, Australia
| | - Vipul Bansal
- Sir Ian Potter NanoBioSensing Facility, RMIT University, Melbourne, Australia
| | - Simon J. Harrison
- Peter MacCallum Cancer Centre and Royal Melbourne Hospital, Melbourne, Australia
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Singla R, Wall D, Anderson S, Zia N, Korte J, Kravets L, McKiernan G, Butler J, Gammilonghi A, Arora J, Wright M, Solomon B, Hicks R, Cain T, Darcy P, Cullinane C, Neeson P, Ramanathan R, Shukla R, Bansal V, Harrison S. First in Human Study of In-vivo Imaging of Ex-Vivo Labelled CAR T Cells with Dual PET-MR. Cytotherapy 2020. [DOI: 10.1016/j.jcyt.2020.04.074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Abstract
Embryonic stem cells (ESCs) represent a mainstay for pluripotent stem cell research and development (R&D) and provide tangible opportunities for clinical translation including cell therapies and drug discovery. Moreover, in spite of the discovery of induced pluripotent stem cells (iPSCs), ESCs are an essential reference point, against which other pluripotent cells are compared. Hence, there is an ongoing need to derive and bank quality-controlled research-grade and clinical-grade ESC lines using established and standardized methods. Here, we provide a concise, step-by-step protocol for the derivation of ESCs from human embryos. While largely based on previously reported method for clinical-grade human ESC (hESC) line derivation, the protocol is suitable for routine application, although adaptable for clinical-compliance.
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Affiliation(s)
- Jeremy M Crook
- ARC Centre of Excellence for Electromaterials Science, Intelligent Polymer Research Institute, AIIM Facility, Innovation Campus, University of Wollongong, Fairy Meadow, New South Wales, 2519, Australia. .,Illawarra Health and Medical Research Institute, University of Wollongong, Wollongong, New South Wales, 2522, Australia. .,Department of Surgery, St Vincent's Hospital, The University of Melbourne, Fitzroy, Victoria, 3065, Australia.
| | - Lucy Kravets
- Centre for Blood Cell Therapies, Peter MacCallum Cancer Centre, East Melbourne, Australia
| | - Teija Peura
- Genea Biomedx, Level 2, 321 Kent Street, Sydney, NSW, 2000, Australia
| | - Meri T Firpo
- Department of Medicine, Division of Endocrinology and Stem Cell Institute, McGuire Translational Research Facility, University of Minnesota, 2001 6th Street SE, Mail Code 2873, Minneapolis, MN, 55455, USA
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Ritchie DS, Neeson PJ, Khot A, Peinert S, Tai T, Tainton K, Chen K, Shin M, Wall DM, Hönemann D, Gambell P, Westerman DA, Haurat J, Westwood JA, Scott AM, Kravets L, Dickinson M, Trapani JA, Smyth MJ, Darcy PK, Kershaw MH, Prince HM. Persistence and efficacy of second generation CAR T cell against the LeY antigen in acute myeloid leukemia. Mol Ther 2013; 21:2122-9. [PMID: 23831595 DOI: 10.1038/mt.2013.154] [Citation(s) in RCA: 324] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 06/24/2013] [Indexed: 01/01/2023] Open
Abstract
In a phase I study of autologous chimeric antigen receptor (CAR) anti-LeY T-cell therapy of acute myeloid leukemia (AML), we examined the safety and postinfusion persistence of adoptively transferred T cells. Following fludarabine-containing preconditioning, four patients received up to 1.3 × 109 total T cells, of which 14-38% expressed the CAR. Grade 3 or 4 toxicity was not observed. One patient achieved a cytogenetic remission whereas another with active leukemia had a reduction in peripheral blood (PB) blasts and a third showed a protracted remission. Using an aliquot of In111-labeled CAR T cells, we demonstrated trafficking to the bone marrow (BM) in those patients with the greatest clinical benefit. Furthermore, in a patient with leukemia cutis, CAR T cells infiltrated proven sites of disease. Serial PCR of PB and BM for the LeY transgene demonstrated that infused CAR T cells persisted for up to 10 months. Our study supports the feasibility and safety of CAR-T-cell therapy in high-risk AML, and demonstrates durable in vivo persistence.
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Affiliation(s)
- David S Ritchie
- 1] Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Australia [2] Hematology Immunology Translational Research Laboratory, Peter MacCallum Cancer Centre, East Melbourne, Australia [3] Cancer Immunology Research Program, Peter MacCallum Cancer Centre, East Melbourne, Australia [4] Division of Cancer Medicine, Peter MacCallum Cancer Centre, East Melbourne, Australia [5] Centre for Blood Cell Therapies, Peter MacCallum Cancer Centre, East Melbourne, Australia
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Neeson P, Ritchie D, Khot A, Peinert S, Tai T, Honemann D, Gambell P, Westerman D, Westwood J, Scott A, Kravets L, Dickinson M, Trapani J, Smyth M, Darcy P, Kershaw M, Prince H. In vivo trafficking, persistence and efficacy of Lewis-Y chimeric antigen receptor T cells in patients with Lewis-Y positive acute myeloid leukaemia (P4354). The Journal of Immunology 2013. [DOI: 10.4049/jimmunol.190.supp.177.10] [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] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Second generation chimeric antigen receptor (CAR) T cells were used to treat patients with acute myeloid leukemia (AML) in a phase I clinical study. Autologous T cells were genetically modified to express a CAR which re-directed T cell effector function to the LeY tumor associated carbohydrate antigen on AML cells. CAR-T cell therapy safety, AML disease response, and CAR-T cell trafficking and persistence post-infusion were investigated. Five patients received GMP grade CAR-T cells (LeY-T). Post infusion, no patients experienced grade 3 or 4 toxicities. Patient AML responses to LeY-T cell infusion included a transient cytogenetic response and a reduction in peripheral blood leukemic blast count. In all patients, LeY-T cells trafficked thru peripheral blood, and persisted in the bone marrow. In one patient, leukemia cutis was associated with trafficking of the LeY-T cells to the skin at sites of AML blast infiltration. Despite LeY-T cells being present at the disease site, relapse with LeY-expressing AML blasts occurred in all patients (range 29 days to 23 months) post-infusion. Further studies indicated LeY-T cell CAR expression was downregulated post-infusion in vivo, this was also observed post-LeY antigen exposure and long term culture in vitro. This study provides important safety and feasibility data to support the application of CAR-T cell therapy to treat AML. Furthermore, we provide a potential mechanism for tumor escape from LeY-T cell surveillance in vivo.
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Affiliation(s)
- Paul Neeson
- 1Cancer Immunology Research, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - David Ritchie
- 1Cancer Immunology Research, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
- 2Haematology Department, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
- 4Center for Blood Cell Therapy, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Amit Khot
- 2Haematology Department, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Stefan Peinert
- 2Haematology Department, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Tsin Tai
- 1Cancer Immunology Research, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Dirk Honemann
- 2Haematology Department, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Peter Gambell
- 3Pathology Department, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - David Westerman
- 3Pathology Department, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Jennifer Westwood
- 1Cancer Immunology Research, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Andrew Scott
- 5Tumor targeting program, Ludwig Inst. for Cancer Res., Melbourne, VIC, Australia
| | - Lucy Kravets
- 4Center for Blood Cell Therapy, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Michael Dickinson
- 2Haematology Department, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Joseph Trapani
- 1Cancer Immunology Research, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Mark Smyth
- 1Cancer Immunology Research, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Phillip Darcy
- 1Cancer Immunology Research, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - Michael Kershaw
- 1Cancer Immunology Research, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
| | - H. Prince
- 2Haematology Department, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
- 4Center for Blood Cell Therapy, Peter MacCallum Cancer Ctr., Melbourne, VIC, Australia
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Khot A, Ritchie D, Neeson P, Peinert S, Tai T, Kravets L, Chen K, Hoenemann D, Shin M, Tainton K, Westwood J, Kershaw M, Haurat J, Trapani J, Smyth M, Darcy P, Scott A, Wall D, Gambell P, Dickinson M, Westerman D, Hicks R, Prince M. Autologous peripheral blood T lymphocytes transduced with an anti lewisy chimeric receptor gene can be infused safely and persist in patients with lewisy positive acute myeloid leukaemia. Cytotherapy 2013. [DOI: 10.1016/j.jcyt.2013.01.048] [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: 10/27/2022]
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Crook JM, Peura TT, Kravets L, Bosman AG, Buzzard JJ, Horne R, Hentze H, Dunn NR, Zweigerdt R, Chua F, Upshall A, Colman A. The generation of six clinical-grade human embryonic stem cell lines. Cell Stem Cell 2008; 1:490-4. [PMID: 18938745 DOI: 10.1016/j.stem.2007.10.004] [Citation(s) in RCA: 150] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Lackmann M, Oates AC, Dottori M, Smith FM, Do C, Power M, Kravets L, Boyd AW. Distinct subdomains of the EphA3 receptor mediate ligand binding and receptor dimerization. J Biol Chem 1998; 273:20228-37. [PMID: 9685371 DOI: 10.1074/jbc.273.32.20228] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Eph receptor tyrosine kinases and their ligands (ephrins) are highly conserved protein families implicated in patterning events during development, particularly in the nervous system. In a number of functional studies, strict conservation of structure and function across distantly related vertebrate species has been confirmed. In this study we make use of the observation that soluble human EphA3 (HEK) exerts a dominant negative effect on somite formation and axial organization during zebrafish embryogenesis to probe receptor function. Based on exon structure we have dissected the extracellular region of EphA3 receptor into evolutionarily conserved subdomains and used kinetic BIAcore analysis, mRNA injection into zebrafish embryos, and receptor transphosphorylation analysis to study their function. We show that ligand binding is restricted to the N-terminal region encoded by exon III, and we identify an independent, C-terminal receptor-dimerization domain. Recombinant proteins encoding either region in isolation can function as receptor antagonists in zebrafish. We propose a two-step mechanism of Eph receptor activation with distinct ligand binding and ligand-independent receptor-receptor oligomerization events.
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Affiliation(s)
- M Lackmann
- Ludwig Institute for Cancer Research (Melbourne Branch), Post Office, Royal Melbourne Hospital, Victoria 3050, Australia
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Lackmann M, Mann RJ, Kravets L, Smith FM, Bucci TA, Maxwell KF, Howlett GJ, Olsson JE, Vanden Bos T, Cerretti DP, Boyd AW. Ligand for EPH-related kinase (LERK) 7 is the preferred high affinity ligand for the HEK receptor. J Biol Chem 1997; 272:16521-30. [PMID: 9195962 DOI: 10.1074/jbc.272.26.16521] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
HEK is a member of the EPH-like receptor tyrosine kinase family, which appear to have roles in development and oncogenesis. Recently, we purified a soluble HEK ligand which is also a ligand (AL1) for the HEK-related receptor EHK1. Promiscuity appears to be a characteristic feature of interactions between the EPH-like receptors and their ligands, termed ligands for EPH-related kinases (LERKs). This prompted us to analyze the interactions between the HEK exodomain and fusion proteins comprising candidate LERKs and the Fc portion of human IgG1 (Fc) or a FLAGTM-peptide tag by surface plasmon resonance, size exclusion high performance liquid chromatography, sedimentation equilibrium, and transphosphorylation. Our results indicate that AL1/LERK7 is the preferred high-affinity ligand for HEK, forming a stable 1:1 complex with a dissociation constant of 12 nM. As expected the apparent affinities of bivalent fusion proteins of LERKs and the Fc portion of human IgG1 had significantly reduced dissociation rates compared with their monovalent, FLAGTM-tagged derivatives. High-avidity binding of monovalent ligands can be achieved by antibody-mediated cross-linking of monovalent ligands and with LERK7 results in specific phosphorylation of the receptor. By extrapolation, our findings indicate that some of the reported LERK-receptor interactions are a consequence of the use of bivalent ligand or receptor constructs and may be functionally irrelevant.
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Affiliation(s)
- M Lackmann
- Cooperative Research Centre for Cellular Growth Factors, Victoria 3050, Australia
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