T cell immunity. Functional heterogeneity of human memory CD4⁺ T cell clones primed by pathogens or vaccines

Distinct types of CD4(+) T cells protect the host against different classes of pathogens. However, it is unclear whether a given pathogen induces a single type of polarized T cell. By combining antigenic stimulation and T cell receptor deep sequencing, we found that human pathogen- and vaccine-specific T helper 1 (T(H)1), T(H)2, and T(H)17 memory cells have different frequencies but comparable diversity and comprise not only clones polarized toward a single fate, but also clones whose progeny have acquired multiple fates. Single naïve T cells primed by a pathogen in vitro could also give rise to multiple fates. Our results unravel an unexpected degree of interclonal and intraclonal functional heterogeneity of the human T cell response and suggest that polarized responses result from preferential expansion rather than priming

Tumor organoid–T-cell coculture systems

T cells are key players in cancer immunotherapy, but strategies to expand tumor-reactive cells and study their interactions with tumor cells at the level of an individual patient are limited. Here we describe the generation and functional assessment of tumor-reactive T cells based on cocultures of tumor organoids and autologous peripheral blood lymphocytes. The procedure consists of an initial coculture of 2 weeks, in which tumor-reactive T cells are first expanded in the presence of (IFNγ-stimulated) autologous tumor cells. Subsequently, T cells are evaluated for their capacity to carry out effector functions (IFNγ secretion and degranulation) after recognition of tumor cells, and their capacity to kill tumor organoids. This strategy is unique in its use of peripheral blood as a source of tumor-reactive T cells in an antigen-agnostic manner. In 2 weeks, tumor-reactive CD8+ T-cell populations can be obtained from ~33–50% of samples from patients with non-small-cell lung cancer (NSCLC) and microsatellite-instable colorectal cancer (CRC). This enables the establishment of ex vivo test systems for T-cell-based immunotherapy at the level of the individual patient

through use of a novel T cell antigen receptor. A universal strategy for adoptive immunotherapy of cancer Updated Version E-mail alerts A universal strategy for adoptive immunotherapy of cancer through use of a novel T cell antigen receptor

ABSTRACT Adoptive immunotherapies composed of T cells engineered to express a chimeric antigen receptor (CAR) offer an attractive strategy for treatment of human cancer. However, CARs have a fixed antigen specificity such that only one tumor-associated antigen (TAA) can be targeted, limiting the efficacy that can be achieved due to heterogeneous TAA expression. For this reason, a more generalized and effective application of CAR therapy would benefit from the capability to produce large panels of CARs against many known TAAs. In this study, we demonstrate a novel strategy to extend the recognition specificity Together, our findings demonstrate that a platform of universal T cell specificity can significantly extend conventional CAR approaches, permitting the tailored generation of T cells of unlimited antigen specificity for improving the effectiveness of adoptive T cell immunotherapies for cancer

Ipilimumab in pretreated metastastic uveal melanoma patients. Results of the Dutch Working group on Immunotherapy of Oncology (WIN-O)

Experimentele farmacotherapi

Low and variable tumor reactivity of the intratumoral TCR repertoire in human cancers

Infiltration of human cancers by T cells is generally interpreted as a sign of immune recognition, and there is a growing effort to reactivate dysfunctional T cells at such tumor sites1. However, these efforts only have value if the intratumoral T cell receptor (TCR) repertoire of such cells is intrinsically tumor reactive, and this has not been established in an unbiased manner for most human cancers. To address this issue, we analyzed the intrinsic tumor reactivity of the intratumoral TCR repertoire of CD8+ T cells in ovarian and colorectal cancer—two tumor types for which T cell infiltrates form a positive prognostic marker2,3. Data obtained demonstrate that a capacity to recognize autologous tumor is limited to approximately 10% of intratumoral CD8+ T cells. Furthermore, in two of four patient samples tested, no tumor-reactive TCRs were identified, despite infiltration of their tumors by T cells. These data indicate that the intrinsic capacity of intratumoral T cells to recognize adjacent tumor tissue can be rare and variable, and suggest that clinical efforts to reactivate intratumoral T cells will benefit from approaches that simultaneously increase the quality of the intratumoral TCR repertoire

Generation of Tumor-Reactive T Cells by Co-culture of Peripheral Blood Lymphocytes and Tumor Organoids

Cancer immunotherapies have shown substantial clinical activity for a subset of patients with epithelial cancers. Still, technological platforms to study cancer T-cell interactions for individual patients and understand determinants of responsiveness are presently lacking. Here, we establish and validate a platform to induce and analyze tumor-specific T cell responses to epithelial cancers in a personalized manner. We demonstrate that co-cultures of autologous tumor organoids and peripheral blood lymphocytes can be used to enrich tumor-reactive T cells from peripheral blood of patients with mismatch repair-deficient colorectal cancer and non-small-cell lung cancer. Furthermore, we demonstrate that these T cells can be used to assess the efficiency of killing of matched tumor organoids. This platform provides an unbiased strategy for the isolation of tumor-reactive T cells and provides a means by which to assess the sensitivity of tumor cells to T cell-mediated attack at the level of the individual patient

Generation of Tumor-Reactive T Cells by Co-culture of Peripheral Blood Lymphocytes and Tumor Organoids

Cancer immunotherapies have shown substantial clinical activity for a subset of patients with epithelial cancers. Still, technological platforms to study cancer T-cell interactions for individual patients and understand determinants of responsiveness are presently lacking. Here, we establish and validate a platform to induce and analyze tumor-specific T cell responses to epithelial cancers in a personalized manner. We demonstrate that co-cultures of autologous tumor organoids and peripheral blood lymphocytes can be used to enrich tumor-reactive T cells from peripheral blood of patients with mismatch repair-deficient colorectal cancer and non-small-cell lung cancer. Furthermore, we demonstrate that these T cells can be used to assess the efficiency of killing of matched tumor organoids. This platform provides an unbiased strategy for the isolation of tumor-reactive T cells and provides a means by which to assess the sensitivity of tumor cells to T cell-mediated attack at the level of the individual patient. A modified patient-derived tumor organoids system allows the expansion of tumor-specific T cells from blood for personalized analysis of their anti-cancer properties