Differential gene expression profiling of CD19CAR-T cell incorporated B-cell costimulatory signaling domain. Enrichment of T-cell proliferation and memory gene signatures of CD79A/CD40 costimulatory domain potentiates CD19CAR-T cell functions

CD19 chimeric antigen receptor (CAR) T-cell has demonstrated remarkable outcomes in B-cell malignancies. Recently, the novel CD19CAR-T cell incorporated with the B-cell costimulatory molecules of CD79A/CD40 has demonstrated superior antitumor activity in the B-cell lymphoma model compared to CD28 or 4-1BB. Here, we investigated the intrinsic transcriptional gene underlying the functional advantage of CD19.79A.40z CAR-T cells following CD19 antigen exposure using transcriptome analysis compared to CD28 or 4‐1BB. Notably, CD19.79A.40z CAR‐T cells up‐regulated genes involved in T‐cell activation, T‐cell proliferation, and NF‐κB signaling, whereas down-regulated genes were associated with T-cell exhaustion and apoptosis. Interestingly, CD19.79A.40z CAR- and CD19.BBz CAR-T cells were enriched in almost similar pathways. Furthermore, gene set enrichment analysis demonstrated the enrichment of genes, which were previously identified to correlate with T-cell proliferation, interferon signaling pathway, naïve and memory T-cell signatures, and down-regulated T-cell exhausted genes in CD79A/CD40, were compared with the T-cell costimulatory domain. The CD19.79A.40z CAR-T cells also up-regulated genes related to glycolysis and fatty acid metabolism, which are necessary to drive T-cell proliferation and differentiation compared to conventional CD19CAR-T cells. Our study provides a comprehensive insight into the understanding of gene signatures that potentiates the superior antitumor functions by CD19CAR-T cells incorporated with the CD79A/CD40 costimulatory domain.