Identification of tumor reactive T cell receptors through functional single cell interaction...

Presented By:
Stefan Eichmüller, PhD
Speaker Biography:
Dr. Eichmüller is heading the Research Group GMP & T Cell Therapy at the German Cancer Research Center (DKFZ) in Heidelberg. He has more than 20 years of experience in research on tumor immunology and, more recently, the role of miRNAs in tumor progression and immune responses. His present interest is to optimize immunotherapy of cancer, including the identification of tumor-specific TCRs and the manipulation of the tumor-microenvironment. Furthermore, he is investigating the impact of radiation therapy on the immune response.
Moreover, Dr. Eichmüller is heading a GMP facility at DKFZ and serves as Qualified Person for the production of autologous, tumor-specific T cells for the treatment of cancer patients. Present applications comprise expanded, tumor-infiltrating lymphocytes and CAR-T cells.
Webinar:
Identification of tumor-reactive T cell receptors through functional single cell interaction analyses for personalized T cell therapy
Webinar Abstract:
Cancer immunotherapy approaches such as adoptive transfer of chimeric antigen receptor (CAR) T cells or tumor-infiltrating lymphocytes have yielded promising results in hematological malignancies. Despite inducing deep responses in multiple myeloma, both antigen escape and limited persistence lead to CAR-T cell therapy resistance. Since multiple myeloma remains an incurable malignancy, novel therapeutic approaches are urgently needed. Adoptive transfer of T cells expressing an engineered T cell receptor (TCR-T cells) represent a promising therapeutic alternative. In contrast to CAR-T cells, TCR-T cells can additionally target intracellular antigens, thereby expanding the range of potential immunotherapeutic targets. Furthermore, TCR-T cell therapy may lead to prolonged persistence in vivo and could mediate sustained anti-tumor effects.
In our project, we identified TCRs specifically targeting autologous myeloma cells. Myeloma-reactive T cells were identified applying nanofluidics and opto-electropositioning using the Bruker Cellular Analysis Lightning® platform. This enabled simultaneous functional analysis of up to 1500 individual T cell/target cell interactions on a chip. Myeloma-reactive T cells were discovered based on the secretion of cytokines (IFNγ, IL-2, TNFα) and surface expression of 4-1BB (CD137). Among 15 myeloma patients tested, reactive T cells demonstrating various cytokine secretion patterns and 4-1BB expression were detected (on average 1.2% of T cells screened). Individual myeloma-reactive T cells were isolated and their respective TCR was sequenced. Additionally, single-cell RNA sequencing was conducted for all 15 patients. By mapping TCR sequences of exported T cells to the single-cell RNA sequencing data, a gene expression signature of myeloma-reactive T cells was established. Genomic TCR sequences were in vitro transcribed and electroporated into autologous CD8+ T cells, followed by co-culture with myeloma cells or PBMCs as negative control. Myeloma-reactivity of transgenic T cells was determined for three patients (n = 11 TCRs) by flow cytometric measurement of T cell activation markers CD69 and 4-1BB. Through immuno-precipitation of MHC I molecules and mass spectrometry of the eluted peptides, we identified T cell responses against both shared and private cancer antigens for 12 patients.
To summarize, we established a pipeline for the identification and functional validation of myeloma-reactive T cells. Together with the evidence of expressed shared and private myeloma derived antigens, we envision this approach to facilitate patient-individualized T cell therapy for multiple myeloma patients.
Labroots on Social:
Facebook: / labrootsinc
Twitter: / labroots
LinkedIn: / labroots
Instagram: / labrootsinc
Pinterest: / labroots
SnapChat: labroots_inc