Differentiation, regulation and function of regulatory T cells in non-lymphoid tissues and tumors

Abstract

Regulatory T cells (Tregs) play a substantial role in inhibiting excessive immune response. A large number of studies have focused on the tissue homeostasis maintenance and remodeling characteristics of Tregs in non-lymphoid tissues, such as the skin, colon, lung, brain, muscle, and adipose tissues. Herein, we overview the kinetics of Treg migration to non-lymphoid tissues and adaptation to the specific tissue microenvironment through the development of tissue-specific chemokine receptors, transcription factors, and phenotypes. Additionally, tumor-infiltrating Tregs (Ti-Tregs) play an important role in tumor generation and immunotherapy resistance. The phenotypes of Ti-Tregs are related to the histological location of the tumor and there is a large overlap between the transcripts of Ti-Tregs and those of tissue-specific Tregs. We recapitulate the molecular underpinnings of tissue-specific Tregs, which might shed new light on Treg-based therapeutic targets and biomarkers for inflammatory diseases and cancer.

Keywords: Chemokine; Chemokine receptors; Regulatory T cells; Tissue; Tumor.