Expression of CD20-specific chimeric antigen receptor (CD20-CAR) on Jurkat T cells and evaluation its biological activity

Abstract

CD20 is a potential target for immunotherapy treatments of haematological malignancies due to its specific expression and unique biological property. Over the years, many anti-CD20 monoclonal antibodies (mAbs) have been developed, such as Rituximab, Ibritumomab, Tositumomab, etc., and applied in B cells related to cancer treatments. Recently, a new immunological therapy, namely Chimeric antigen receptor (CAR) T-cell therapy, in which the patient’s T cells are reprogrammed ex vivo with a transgene encoding a CAR in order to active them against the tumour, has emerged as a promising treatment for B-cell malignancies. In this study, the authors generated and expressed two variants of chimeric receptor antigen-specific to CD20 on Jurkat T cells, in which one variant referenced the sequence from the patent (SEQ01) and the other was our own designed sequence (SEQ02). The transient expression after electroporation 24 hours confirmed the presence of mRNA and protein of CD20-CAR in both sequences. Moreover, these chimeric receptors were also detected on the membrane of Jurkat cells using flow cytometer analysis, indicating that the author could successfully transduce and express CD20-CAR in Jurkat cells. Co-culture CD20-Jurkat-CAR-T cells with CD20-expressing Raji B cells show that the generated Jurkat could be activated via their chimeric receptors through increasing the secretion of Interleukin-2 in both sequences. Taken together, our preliminary data suggest that the authors have been able to express the CD20-activating functional transgenic receptor on Jurkat cells, which will be applied for generating CD20-CAR-expressing CD4⁺/CD8⁺ T cells.