Abstract IA36: Regulatory T cells, polymorphisms, and response to checkpoint blockade: From mechanisms to potential biomarkers

Abstract

In mice, anti-CTLA-4 monoclonal antibodies (mAbs) require Fc-gamma receptor (FcγR)-mediated depletion of intratumoral regulatory T (Treg) cells to promote tumor rejection. However, the relevance of this mechanism in the human setting remains controversial. Using a mouse model expressing human FcγRs, and analysis of clinical samples from ipilimumab-treated melanoma patients, we investigate the potential role of Treg depletion in the activity of antibodies targeting human CTLA-4. Citation Format: Sergio Quezada. Regulatory T cells, polymorphisms, and response to checkpoint blockade: From mechanisms to potential biomarkers [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr IA36.