Construction and Functional Characterization of a Fully Human Anti-Cd19 Chimeric Antigen Receptor (Hucar)-Expressing Primary Human T Cells Publisher Pubmed



Mirzaei HR¹ ; Jamali A^{2, 3} ; Jafarzadeh L¹ ; Masoumi E¹ ; Alishah K⁴ ; Fallah Mehrjardi K¹ ; Emami SAH⁵ ; Noorbakhsh F¹ ; Till BG⁶ ; Hadjati J¹ Show Affiliations
Source: Journal of Cellular Physiology Published:2019

Abstract

Although remarkable results have been attained by adoptively transferring T cells expressing fully murine and/or humanized anti-CD19 chimeric antigen receptors (CARs) to treat B cell malignancies, evidence of human anti-mouse immune responses against CARs provides a rationale for the development of less immunogenic CARs. By developing a fully human CAR (huCAR), these human anti-mouse immune responses are likely eliminated. This, perhaps, not only increases the persistence of anti-CD19 CAR T cells—thereby reducing the risk of tumor relapse—but also facilitates administration of multiple, temporally separated doses of CAR T cells to the same recipient. To these ends, we have designed and constructed a second-generation fully human anti-CD19 CAR (or huCAR19) containing a fully human single-chain variable fragment (ScFv) fused with a CD8a hinge, a 4-1BB transmembrane domain and intracellular T cell signaling domains of 4-1BB and CD3z. T cells expressing this CAR specifically recognized and lysed CD19+ target cells produced cytokines and proliferated in vitro. Moreover, cell volume data revealed that our huCAR construct cannot induce antigen-independent tonic signaling in the absence of cognate antigen. Considering our results, our anti-CD19 huCAR may overcome issues of transgene immunogenicity that plague trials utilizing CARs containing mouse-derived ScFvs. These results suggest that this huCAR19 be safely and effectively applied for adaptive T cell immunotherapy in clinical practice. © 2018 Wiley Periodicals, Inc.