Project description:To gain further insight into how CCT fusion engineering impacts their function, we characterized CAR-T cells using transcriptome profiling. We performed mRNA-seq from all four groups of CAR-T cells, either without stimulation (baseline) or with 2 rounds of NALM6GL stimulation. For CAR-T cells that were cocultured with 2 rounds of NALM6GL cells, we sorted the pure CAR-T populations (CAR+; GFP-) before subjecting them to RNA sequencing
Project description:To systematically investigate the effect of CCT engineering on CAR-T cell phenotypes in vivo, we used single-cell RNA sequencing (scRNA-seq) to characterize the full spectrum of engineered CAR-T cells and their transcriptomic profiles
Project description:Chimeric antigen receptor (CAR)-T cells are powerful therapeutics; however, their efficacy is often hindered by critical hurdles. Here utilizing the endocytic feature of the cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) cytoplasmic tail, we reprogram CAR function and substantially enhance CAR-T efficacy in vivo. CAR-T cells with monomeric, duplex or triplex CTLA-4 cytoplasmic tails (CCTs) fused to the C terminus of CAR exhibit a progressive increase in cytotoxicity under repeated stimulation, accompanied by reduced activation and production of proinflammatory cytokines. Further characterization reveals that CARs with increasing CCT fusion show a progressively lower surface expression, regulated by their constant endocytosis, recycling and degradation under steady state. The molecular dynamics of reengineered CAR with CCT fusion results in reduced CAR-mediated trogocytosis, loss of tumor antigen and improved CAR-T survival. CARs with either monomeric (CAR-1CCT) or duplex CCTs (CAR-2CCT) have superior antitumor efficacy in a relapsed leukemia model. Single-cell RNA sequencing and flow cytometry analysis reveal that CAR-2CCT cells retain a stronger central memory phenotype and exhibit increased persistence. These findings illuminate a unique strategy for engineering therapeutic T cells and improving CAR-T function through synthetic CCT fusion, which is orthogonal to other cell engineering techniques.
Project description:To characterize transfer of molecules from target cells into CAR T cells via trogocytosis we cultured NALM-6 leukemia cell line expressing a CD19-mCherry fusion protein with CAR T cells. NALM6-CD19-mCherry were loaded with heavy amino acid and cocultured with CAR T cells for 1 hour. CAR T cells were next sorted into two fractions, mCherry-positive (TrogPos), and -negative (TrogNeg). Proteomics analysis revealed the presence of targeted antigen (CD19) in the TrogPos only.
Project description:Human induced pluripotent stem cells (iPS cells) resemble embryonic stem cells and can differentiate into cell derivatives of all three germ layers. However, frequently the differentiation efficiency of iPS cells into some lineages is rather poor. Here, we found that fusion of iPS cells with human hematopoietic stem cells (HSC) enhances iPS cell differentiation. Such iPS hybrids showed a prominent differentiation bias towards hematopoietic lineages but also towards other mesendodermal lineages. Additionally, during differentiation of iPS hybrids expression of early mesendodermal markers - Brachyury (T), MIX1 Homeobox-Like Protein 1 (MIXL1) and Goosecoid (GSC) - appeared with faster kinetics than in parental iPS cells. Following iPS hybrid differentiation there was a prominent induction of NODAL and inhibition of NODAL signaling blunted mesendodermal differentiation. This indicates that NODAL signaling is critically involved in mesendodermal bias of iPS hybrid differentiation. In summary, we demonstrate that iPS cell fusion with HSC prominently enhances iPS differentiation. 11 samples were hybridized GeneChip Human Gene 1.0 ST Arrays (Affymetrix)
Project description:The tumor microenvironment presents many obstacles to effective CAR T cell therapy, including glucose competition from tumor and myeloid cells. Using mouse models of acute lymphoblastic leukemia (ALL), renal cell carcinoma (RCC), and glioblastoma (GBM), we show that enforced expression of the glucose transporter GLUT1 enhances anti-tumor efficacy and promotes favorable CAR T cell phenotypes for two clinically relevant CAR designs, 19-28z and IL13Ra2-BBz. In the NALM6 ALL model, 19-28z-GLUT1 promotes Tscm formation and prolongs survival. RNA sequencing of these CAR T cells reveals that overexpression of GLUT1, but not GLUT3, enriches for genes involved in glycolysis, mitochondrial respiration, and memory precursor phenotypes. Extending these data, 19-28z-GLUT1 CAR T cells improve tumor control and response to rechallenge in an RCC patient derived xenograft model. Furthermore, IL13Ra2-BBz CAR T cells overexpressing GLUT1 prolong survival of mice bearing orthotopic GBMs and exhibit decreased exhaustion markers. This novel engineering approach can offer a competitive advantage to CAR T cells in harsh tumor environments where glucose is limiting.