Immunometabolism - The Role of Branched-Chain Amino Acids

Immunometabolism has been the focus of extensive research over the last years, especially in terms of augmenting anti-tumor immune responses. Regulatory T cells (Tregs) are a subset of CD4(+) T cells, which have been known for their immunosuppressive roles in various conditions including anti-tumor immune responses. Even though several studies aimed to target Tregs in the tumor microenvironment (TME), such approaches generally result in the inhibition of the Tregs non-specifically, which may cause immunopathologies such as autoimmunity. Therefore, specifically targeting the Tregs in the TME would be vital in terms of achieving a successful and specific treatment. Recently, an association between Tregs and isoleucine, which represents one type of branched-chain amino acids (BCAAs), has been demonstrated. The presence of isoleucine seems to affect majorly Tregs, rather than conventional T cells. Considering the fact that Tregs bear several distinct metabolic features in the TME, targeting their immunometabolic pathways may be a rational approach. In this Review, we provide a general overview on the potential distinct metabolic features of T cells, especially focusing on BCAAs in Tregs as well as in their subtypes.

Automated summary

Immunometabolism, especially in terms of augmenting anti-tumor immune responses, has been extensively researched. Regulatory T cells (Tregs) are known for their immunosuppressive roles in anti-tumor immune responses. Targeting Tregs specifically in the tumor microenvironment (TME) is crucial for successful and specific treatment. Recent studies have shown an association between Tregs and isoleucine, which may play a major role in affecting Tregs. Targeting the immunometabolic pathways of Tregs could be a rational approach for treatment.