Faculty Collaboration Database

Immune tolerance induced by platelet-targeted factor VIII gene therapy in hemophilia A mice is CD4 T cell mediated. J Thromb Haemost 2017 Oct;15(10):1994-2004

Date

08/12/2017

Pubmed ID

28799202

Pubmed Central ID

PMC5630523

DOI

10.1111/jth.13800

Scopus ID

2-s2.0-85029226218 (requires institutional sign-in at Scopus site)   25 Citations

Abstract

UNLABELLED: Essentials The immune response is a significant concern in gene therapy. Platelet-targeted gene therapy can restore hemostasis and induce immune tolerance. CD4 T cell compartment is tolerized after platelet gene therapy. Preconditioning regimen affects immune tolerance induction in platelet gene therapy.

SUMMARY: Background Immune responses are a major concern in gene therapy. Our previous studies demonstrated that platelet-targeted factor VIII (FVIII) (2bF8) gene therapy together with in vivo drug selection of transduced cells can rescue the bleeding diathesis and induce immune tolerance in FVIII^null mice. Objective To investigate whether non-selectable 2bF8 lentiviral vector (LV) for the induction of platelet-FVIII expression is sufficient to induce immune tolerance and how immune tolerance is induced after 2bF8LV gene therapy. Methods Platelet-FVIII expression was introduced by 2bF8LV transduction and transplantation. FVIII assays and tail bleeding tests were used to confirm the success of platelet gene therapy. Animals were challenged with rhF8 to explore if immune tolerance was induced after gene therapy. Treg cell analysis, T-cell proliferation assay and memory B-cell-mediated ELISPOT assay were used to investigate the potential mechanisms of immune tolerance. Results We showed that platelet-FVIII expression was sustained and the bleeding diathesis was restored in FVIII^null mice after 2bF8LV gene therapy. None of the transduced recipients developed anti-FVIII inhibitory antibodies in the groups preconditioned with 660 cGy irradiation or busulfan plus ATG treatment even after rhF8 challenge. Treg cells significantly increased in 2bF8LV-transduced recipients and the immune tolerance developed was transferable. CD4⁺ T cells from treated animals failed to proliferate in response to rhF8 re-stimulation, but memory B cells could differentiate into antibody secreting cells in 2bF8LV-transduced recipients. Conclusion 2bF8LV gene transfer without in vivo selection of manipulated cells can introduce immune tolerance in hemophilia A mice and this immune tolerance is CD4⁺ T cell mediated.

Author List

Chen Y, Luo X, Schroeder JA, Chen J, Baumgartner CK, Hu J, Shi Q

Author

Qizhen Shi MD, PhD Professor in the Pediatrics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Antibodies
B-Lymphocytes
Blood Platelets
Bone Marrow Transplantation
Cells, Cultured
Disease Models, Animal
Factor VIII
Female
Genetic Predisposition to Disease
Genetic Therapy
Hemophilia A
Humans
Immune Tolerance
Immunologic Memory
Immunosuppressive Agents
Lymphocyte Activation
Male
Mice, Inbred C57BL
Mice, Knockout
Phenotype
T-Lymphocytes, Regulatory
Transduction, Genetic