Project description:Purpose: To compare cell states amoung three populations of interest among circulating CAR T cells in patients with lymphoma. Methods: Nine patients with large B-cell lymphoma (LBCL) were treated with axicabtagene ciloleucel (axi-cel), a commercial CD19-targeted CAR T-cell therapy. On day 7, fresh peripheral blood mononuclear cells were stained with an antibody panel for fluorescence-activated cell sorting (FACS), a panel for cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq), and a viability dye. Single live CAR+ T cells were sorted from each patient, counted, processed for 5' single-cell RNA-sequencing with feature barcoding and TCR clonotype analysis on the 10X Genomics platform, and sequenced by the Stanford Genomics Facility (HighSeq 4000) or Novogene (NovaSeq 6000). Results: We found that circulating CD4+ and CD8+ CAR T cells that express CD57 and T-bet are clonally expanded and display features of effector T cells. In contrast, CD4+ CD57- CAR T cells that express Helios expand polyclonally and display features of T regulatory cells. Conclusions: This study provides insights into cell states of circulating CAR T cells on day 7 that associate with clinical response or toxicity in LBCL patients treated with axi-cel.
Project description:CD19-directed chimeric antigen receptor (CAR) T cells can induce durable remissions in relapsed/refractory large B-cell lymphomas (R/R LBCL), but 60% of patients still relapse. Biological mechanisms explaining lack of disease-response are largely unknown. To identify mechanisms of response and survival before CAR T manufacturing in 95 R/R LBCL receiving tisagenlecleucel or axicabtagene ciloleucel, we performed phenotypic, transcriptomic and functional evaluations of leukapheresis products (LK). Transcriptomic profiling of T cells in LK, revealed a signature composed of 4 myeloid genes able to identify patients with very short progression-free survival, highlighting the role of monocytes in CAR T therapy response. Accordingly, response and survival were negatively influenced by high circulating absolute monocyte counts at the time of leukapheresis, and the combined evaluation of peripheral blood monocytes and the four-gene signature in LK, identifies LBCL patients at very high risk of progression after CAR T.
Project description:Chimeric antigen receptor (CAR) T cell therapies have revolutionized B cell malignancy treatment, but subsets of patients with large B cell lymphoma (LBCL) experience primary resistance or relapse after CAR T cell treatment. To uncover tumor microenvironment (TME)-induced resistance mechanisms, we examined patients’ intratumoral immune infiltrates and observed that elevated levels of immunoregulatory macrophages in pre-infusion tumor biopsies are correlated with poor clinical responses. In murine models, CAR T cell-produced interferon-gamma (IFN-g) promotes the expression of inducible nitric oxide synthase (iNOS, NOS2) in immunoregulatory macrophages, impairing CAR T cell function. Mechanistically, proteomics analysis of CAR T cells revealed that iNOS-expressing macrophages promote the upregulation of genes mediating apoptosis and cell cycle arrest in CAR T cells, while downregulating ribosome biogenesis and protein synthesis. Furthermore, CAR T cell metabolism is compromised by the depletion of glycolytic intermediates and rewiring of the TCA cycle. Pharmacological inhibition of iNOS enhances the CAR T cell treatment efficacy in B cell tumor-bearing mice. Notably, elevated levels of iNOS+CD14+ monocytes were observed in leukaphereses of patients with non-durable response to CAR T cell therapy. These findings suggest that mitigating iNOS in tumor-associated macrophages (TAMs), potentially by modulating IFN-g expression in CAR T cells, could improve outcomes for LBCL patients.
Project description:Chimeric antigen receptor (CAR) T cell therapies have revolutionized B cell malignancy treatment, but subsets of patients with large B cell lymphoma (LBCL) experience primary resistance or relapse after CAR T cell treatment. To uncover tumor microenvironment (TME)-induced resistance mechanisms, we examined patients’ intratumoral immune infiltrates and observed that elevated levels of immunoregulatory macrophages in pre-infusion tumor biopsies are correlated with poor clinical responses. In murine models, CAR T cell-produced interferon-gamma (IFN-g) promotes the expression of inducible nitric oxide synthase (iNOS, NOS2) in immunoregulatory macrophages, impairing CAR T cell function. Mechanistically, proteomics analysis of CAR T cells revealed that iNOS-expressing macrophages promote the upregulation of genes mediating apoptosis and cell cycle arrest in CAR T cells, while downregulating ribosome biogenesis and protein synthesis. Furthermore, CAR T cell metabolism is compromised by the depletion of glycolytic intermediates and rewiring of the TCA cycle. Pharmacological inhibition of iNOS enhances the CAR T cell treatment efficacy in B cell tumor-bearing mice. Notably, elevated levels of iNOS+CD14+ monocytes were observed in leukaphereses of patients with non-durable response to CAR T cell therapy. These findings suggest that mitigating iNOS in tumor-associated macrophages (TAMs), potentially by modulating IFN-g expression in CAR T cells, could improve outcomes for LBCL patients.
Project description:<p>Anti-CD19 chimeric antigen receptor (CAR) T-cell therapy for relapsed or refractory (r/r) large B-cell lymphoma (LBCL) results in durable response in only a subset of patients. MYC overexpression in LBCL tumors is associated with poor response to treatment. We tested whether a MYC-driven polyamine signature, as a liquid biopsy, is predictive of response to anti-CD19 CAR-T therapy in patients with r/r LBCL. Elevated plasma acetylated polyamines were associated with non-durable response. Concordantly, increased expression of spermidine synthase, a key enzyme which regulates levels of acetylated spermidine, was prognostic for survival in r/r LBCL. A broad metabolite screen identified additional markers which resulted in a 6-marker panel (6MetP) consisting of acetylspermidine, diacetylspermidine and lysophospholipids which was validated in an independent set from another institution as predictive of non-durable response to CAR T therapy. A polyamine centric metabolomics liquid biopsy panel has predictive value for response to CAR-T therapy in r/r LBCL. </p>
Project description:Circulating monocyte counts coupled with a 4-gene signature at leukapheresis predict survival of lymphoma patients treated with CAR T
Project description:Immunotherapy using CD19-directed chimeric antigen receptor (CAR)-T cells has shown excellent results for treatment of B-cell leukaemia and lymphoma. To produce CAR-T cells, the patient’s own T cells are isolated from the blood and modified in a laboratory with a genetic vector to express a tumor antigen-directed CAR on its surface. The CAR-T cells are then expanded in numbers and given back to the patient with the aim to eradicate the tumors. However, some patients display primary resistance to CAR-T treatment while others relapse quickly after CAR-T treatment. In this experiment, we seek to understand whether the quality of the individual CAR-T cell product the patients were given can predict outcome to the therapy. We investigate the transcriptional profile of the individual CAR-T infusion products using single-cell RNA sequencing. In this dataset, we identified a T cell subset correlating with response that could be used as an indicator for clinical outcome. Targeted RNA and protein single-cell libraries were obtained using the BD Rhapsody platform (BD Biosciences). In total four separate targeted libraries were produced with 6 patients per library. Sequencing was performed on NovaSeq 6000 S1 sequencer at the SNP&SEQ Technology Platform (Uppsala, Sweden). The raw scRNA-seq data was pre-processed by BD Biosciences using the Rhapsody Analysis pipeline to convert the raw reads into Unique Molecular Identifier (UMI) counts. UMIs are further adjusted within Rhapsody by applying BD’s Recursive Substitution Error Correction (RSEC) and Distribution-Based Error Correction (DBEC) in order to remove false UMIs caused by sequencing or library preparation errors. Pooled samples were deconvoluted using Sample-tag reads. The scRNA-seq and AbSeq counts were loaded, processed and used for clustering and differential gene expression with Seurat v. 4.0.0.
Project description:Chimeric antigen receptor (CAR) T cell therapies have revolutionized B cell malignancy treatment, but subsets of patients with large B cell lymphoma (LBCL) experience primary resistance or relapse after CAR T cell treatment. To uncover tumor microenvironment (TME)-induced resistance mechanisms, we examined patients’ intratumoral immune infiltrates and observed that the elevated levels of immunoregulatory macrophages in pre-infusion tumor biopsies are correlated with poor clinical responses. CAR T cell-produced interferon-gamma (IFN-γ) promotes the expression of inducible nitric oxide synthase (iNOS, NOS2) in immunoregulatory macrophages, impairing CAR T cell functionality. Mechanistically, iNOS-expressing macrophages upregulated the p53 pathway, mediating apoptosis and cell cycle arrest in CAR T cells, while downregulating the MYC pathway involved in ribosome biogenesis and protein synthesis. Furthermore, CAR T cell metabolism is compromised by the depletion of glycolytic intermediates and rewiring of the TCA cycle. Pharmacological inhibition of iNOS enhances the CAR T cell treatment efficacy in B cell tumor-bearing mice. Notably, elevated levels of iNOS+CD14+ monocytes were observed in the leukapheresis material of patients with non-durable response to CAR T cell therapy. These findings suggest that mitigating iNOS in tumor-associated macrophages (TAMs) by blocking IFN-g secretion from CAR T cells will improve outcomes for LBCL patients.
Project description:To investigate the CAR T-cell differentiation in vivo, we performed single-cell, multi-omics analyses of CD28-costimulated CAR T cells from patients with DLBCL who were successfully treated with axicabtagene ciloleucel. Our data shows that CAR T cells undergo two distinct stages of post-infusion clonal expansion.