Abstract 4484: ScRNA-seq of patients with immune-related adverse events and checkpoint inhibitor therapy

Abstract

Abstract Despite the remarkable success of immune checkpoint inhibitor (ICI) therapy, a significant number of patients develop severe and unpredictable immune-related adverse events (irAEs) affecting a wide variety of organs. Concerns over irAE have led to the exclusion of patients with autoimmune disease from ICI clinical trials. Role of host genetic and immune factors in mediating irAEs remain unclear and it is not clear if the manifestations of irAEs is associated with response to therapy. In this study, we used single cell RNA sequencing (ScRNA-seq) to study the peripheral immune repertoire at a single cell level to identify blood-based signatures predictive of irAEs and response to ICI therapy. We characterized changes in host immune system in 40 patients receiving ICI therapy by performing ScRNA-seq on peripheral blood mononuclear cells (PBMCs) at baseline and post-immunotherapy. In addition, we evaluated serum levels of 40 cytokines/chemokines, antinuclear autoantibodies (ANA) and 124 autoantibodies and performed bulk RNA sequencing on PBMCs at baseline and post immunotherapy in these patients. Our preliminary data analysis identified signatures of autoantibodies and cytokines correlating with response and toxicity. ScRNA-seq data revealed changes in distinct immune cell subsets and gene expression signatures in patient developing irAEs. In this meeting, we will present preliminary ScRNA-seq data combined with immune and genetic correlates of irAEs and response to therapy in our patient cohort. We hope that our studies can help identify blood-based biomarker signatures predictive of irAEs and/or response and reveal novel insights into the mechanisms underlying irAE. Our current genetic data suggests further expanding the genetic studies in larger patient population to identify the role of underlying genetic predisposition to autoimmunity in mediating irAEs. We hope our findings may ultimately help customize therapy, expand use of immunotherapy and prevent toxicities. Citation Format: Shaheen Khan, David E. Gerber. ScRNA-seq of patients with immune-related adverse events and checkpoint inhibitor therapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4484.