Project description:In this data set we include expression data from human CD4+ T cells isolated on day 0, 6, 11 and 24 follow anti-CD3/anti-CD28 magnetic bead stimulation and chimeric antigen receptor transduction. 30 samples were submitted. Samples represented three biological replicates of normal donors transduced with various CARs. CARs used were a cMet 28z specific CAR comprised of the IgG4 hinge, CD28 transmembrane and CD28 and CD3zeta intracellular domains. A CD19 CD28 CAR was specific to CD19, and was comprised of a CD8a hinge, CD28 transmembrane and CD28 and CD3zeta intracellular domain. A third CAR, the CD19 BBz, was used that was specific to CD19 was comprised of a CD8a hinge, CD8a transmembrane and 4-1BB and CD3zeta intracellular domains. Expression data was analyzied on day 0, 6, 11 and 24.
Project description:Murine chimeric antigen receptor transduced T cells (CAR-T cells) deficient in perforin recapitulate hemophagocytic lymphohistiocytosis (HLH)-like toxicities occuring in human CAR-T recipients. We used microarray to describe gene expression profiles of wild-type and perforin-deficient CAR-T cells.
Project description:In vivo persistence of chimeric antigen receptor (CAR) T cells correlates with therapeutic efficacy, yet CAR-specific factors that support persistence are not well resolved. Using a CAR containing a single chain variable fragment (scFv) specific for CD33 linked to a 4-1BB and CD3 zeta signaling domain that is currently in advanced clinical trials, we show that CAR-expression, in a ligand-independent manner, alters T cell differentiation during ex vivo expansion. CAR-transduced T cells displayed decreased naïve and stem memory populations and increased effector subsets relative to vector-transduced control cells, and this was associated with reduced in vivo persistence. Altered persistence was not due to antigen specificity or tumor presence, but was linked to tonic signaling through the CAR, most notably CD3 zeta ITAMs, prior to transfer. We identified the PI3K/AKT pathway in CD33 CAR T cells as responsible. Treatment with a PI3K inhibitor modulated the differentiation program of CAR T cells, preserved a less differentiated state without affecting T cell expansion, and improved in vivo persistence relative to control cells. These results help resolve mechanisms by which tonic signaling modulates CAR T cell fate, and identifies a novel pharmacologic approach to enhance the durability of CAR T cells for cell-based immunotherapy.
Project description:The aim of the study was to compare and contrast cytokine production by CD4+ chimeric antigen receptor + T-cells and putative myeloid derived suppressor cell populations (CD11b+Gr-1 hi and lo) in the spleens of Balb/c mice which had received a transfer of CD19 specific second-generation CAR T-cells 56 days previously following cyclophosphamide pre-conditioning. Splenocytes from four individual mice were pooled, incubated with antibodies to CD4, CD34 (CAR), CD11b, Gr-1 and sorted using flow cytometric cell sorting for CD4+CD34+, Gr-1 and the negative cell fraction. Total RNA was isolated and samples loaded in duplicate in the array. Data was normalized to global expression levels.
Project description:This mathematical model of T cell-tumour interactions considering the roles of T cell competition and stochastic extinction events in CAR T cell therapy is described by the publication:
Kimmel GJ, Locke FL, Altrock PM. "The roles of T cell competition and stochastic extinction events in chimeric antigen receptor T cell therapy." Proc Biol Sci. 2021 Mar 31;288(1947):20210229.
doi: 10.1098/rspb.2021.0229
Comment:
Reproduction of Fig. 2(a) and (b) was simulated by using the fitted model parameter set given in Table 1 of the manuscript's Supplementary Material, however substituting the values of r_N and rho_C for those stated in Table 1 of the publication manuscript, i.e. r_N = 0.17 and rho_C = 0.0251.
Abstract:
Chimeric antigen receptor (CAR) T cell therapy is a remarkably effective immunotherapy that relies on in vivo expansion of engineered CAR T cells, after lymphodepletion (LD) by chemotherapy. The quantitative laws underlying this expansion and subsequent tumour eradication remain unknown. We develop a mathematical model of T cell–tumour cell interactions and demonstrate that expansion can be explained by immune reconstitution dynamics after LD and competition among T cells. CAR T cells rapidly grow and engage tumour cells but experience an emerging growth rate disadvantage compared to normal T cells. Since tumour eradication is deterministically unstable in our model, we define cure as a stochastic event, which, even when likely, can occur at variable times. However, we show that variability in timing is largely determined by patient variability. While cure events impacted by these fluctuations occur early and are narrowly distributed, progression events occur late and are more widely distributed in time. We parameterized our model using population-level CAR T cell and tumour data over time and compare our predictions with progression-free survival rates. We find that therapy could be improved by optimizing the tumour-killing rate and the CAR T cells' ability to adapt, as quantified by their carrying capacity. Our tumour extinction model can be leveraged to examine why therapy works in some patients but not others, and to better understand the interplay of deterministic and stochastic effects on outcomes. For example, our model implies that LD before a second CAR T injection is necessary.
Project description:Despite initial high-rates of complete response, <50% of B-cell acute lymphoblastic leukemia (B-ALL) patients treated with CD19-directed chimeric antigen receptor (CAR)-T cells maintain durable remissions. We integrated clonal kinetics and genetic heterogeneity with single-cell-TCR sequencing and single-cell-RNA sequencing, respectively, to explore the cellular dynamics response of both non-transduced (CARneg) and transduced (CARpos) T-cells. CARneg and CARpos T-cells were longitudinally interrogated in the manufactured infusion product (IP) and in peripheral blood at the time of CAR-T cell expansion peak following infusion in five adult B-ALL patients treated with CD19CAR-T products.
Project description:Cell culture conditions impact the clinical efficacy of chimeric antigen receptor (CAR) T cell products, but the optimal approach remains unknown. Separate CD4+ and CD8+ cultures offer a potential advantage but complicate manufacturing and may affect cell expansion and function. We evaluated the co-culture of CD4+ and CD8+ cells at a defined ratio at culture initiation. We observed that the presence of CD4+ cells markedly improves expansion of CD8+ CAR T cells, and CD8+ cells cultured in isolation exhibit a hypofunctional phenotype and transcriptional signature compared with those co-cultured with CD4+ cells. Mixed-culture CAR T cells also confer superior anti-tumor activity in vivo compared with separately expanded, co-infused cells. CD4+ cell effects on CD8+ cells are mediated through both cytokines and direct cell contact, including CD40L-CD40 and CD70-CD27 interactions.
Project description:Failure of adoptive T cell therapies in cancer patients is linked to limited T cell expansion and persistence, even in memory-prone 41BB-(BBz)-based chimeric antigen receptor (CAR) T cells. In murine CD8+ T cells, SUV39H1 promotes differentiation and expansion of effector CD8+ T cells during acute infection by Listeria monocytogenes by silencing stemness and memory genes (Pace et al. Science, 2018). The purpuse of this study is to investigate the transcriptomic differences of SUV39H1 knock-out versus mock human 41BBz-CAR T cells by Nanostring at different cycles of restimulation.
Project description:Adoptive transfer of T cells expressing chimeric antigen receptors (CAR-T) effectively treats refractory hematologic malignancies in a subset of patients but can be limited by poor T-cell expansion and persistence in vivo. Less differentiated T-cell states correlate with the capacity of CAR-T to proliferate and mediate antitumor responses, and interventions that limit tumor-specific T-cell differentiation during ex vivo manufacturing enhance efficacy. NOTCH signaling is involved in fate decisions across diverse cell lineages and in memory CD8+ T cells was reported to upregulate the transcription factor FOXM1, attenuate differentiation, and enhance proliferation and antitumor efficacy in vivo. Here, we used a cell-free culture system to provide an agonistic NOTCH1 signal during naïve CD4+ T-cell activation and CAR-T production and studied the effects on differentiation, transcription factor expression, cytokine production, and responses to tumor. NOTCH1 agonism efficiently induced a stem cell memory phenotype in CAR-T derived from naïve but not memory CD4+ T cells and upregulated expression of AhR and c-MAF, driving heightened production of interleukin-22 (IL-22), IL-10, and granzyme B. NOTCH1-agonized CD4+ CAR-T demonstrated enhanced antigen responsiveness and proliferated to strikingly higher frequencies in mice bearing human lymphoma xenografts. NOTCH1-agonized CD4+ CAR-T also provided superior help to cotransferred CD8+ CAR-T, driving improved expansion and curative antitumor responses in vivo at low CAR-T doses. Our data expand the mechanisms by which NOTCH can shape CD4+ T-cell behavior and demonstrate that activating NOTCH1 signaling during genetic modification ex vivo is a potential strategy for enhancing the function of T cells engineered with tumor-targeting receptors.
Project description:Adoptive transfer of T cells expressing chimeric antigen receptors (CAR-T) effectively treats refractory hematologic malignancies in a subset of patients but can be limited by poor T-cell expansion and persistence in vivo. Less differentiated T-cell states correlate with the capacity of CAR-T to proliferate and mediate antitumor responses, and interventions that limit tumor-specific T-cell differentiation during ex vivo manufacturing enhance efficacy. NOTCH signaling is involved in fate decisions across diverse cell lineages and in memory CD8+ T cells was reported to upregulate the transcription factor FOXM1, attenuate differentiation, and enhance proliferation and antitumor efficacy in vivo. Here, we used a cell-free culture system to provide an agonistic NOTCH1 signal during naïve CD4+ T-cell activation and CAR-T production and studied the effects on differentiation, transcription factor expression, cytokine production, and responses to tumor. NOTCH1 agonism efficiently induced a stem cell memory phenotype in CAR-T derived from naïve but not memory CD4+ T cells and upregulated expression of AhR and c-MAF, driving heightened production of interleukin-22 (IL-22), IL-10, and granzyme B. NOTCH1-agonized CD4+ CAR-T demonstrated enhanced antigen responsiveness and proliferated to strikingly higher frequencies in mice bearing human lymphoma xenografts. NOTCH1-agonized CD4+ CAR-T also provided superior help to cotransferred CD8+ CAR-T, driving improved expansion and curative antitumor responses in vivo at low CAR-T doses. Our data expand the mechanisms by which NOTCH can shape CD4+ T-cell behavior and demonstrate that activating NOTCH1 signaling during genetic modification ex vivo is a potential strategy for enhancing the function of T cells engineered with tumor-targeting receptors.