TH17 cell heterogeneity and its role in tissue inflammation

Since their discovery almost two decades ago, interleukin-17-producing CD4(+) T cells (T(H)17 cells) have been implicated in the pathogenesis of multiple autoimmune and inflammatory disorders. In addition, T(H)17 cells have been found to play an important role in tissue homeostasis, especially in the intestinal mucosa. Recently, the use of single-cell technologies, along with fate mapping and various mutant mouse models, has led to substantial progress in the understanding of T(H)17 cell heterogeneity in tissues and of T(H)17 cell plasticity leading to alternative T cell states and differing functions. In this Review, we discuss the heterogeneity of T(H)17 cells and the role of this heterogeneity in diverse functions of T(H)17 cells from homeostasis to tissue inflammation. In addition, we discuss T(H)17 cell plasticity and its incorporation into the current understanding of T cell subsets and alternative views on the role of T(H)17 cells in autoimmune and inflammatory diseases. Kuchroo and colleagues review T(H)17 cell heterogeneity and discuss how this affects the function of T(H)17 cells in homeostasis and disease.

Automated summary

Since their discovery almost two decades ago, interleukin-17-producing CD4(+) T cells (T(H)17 cells) have been found to be involved in the pathogenesis of autoimmune and inflammatory disorders. Recent advancements in single-cell technologies and mouse models have led to a better understanding of T(H)17 cell heterogeneity and plasticity, along with their diverse functions in homeostasis and inflammation. The review discusses the role of T(H)17 cell heterogeneity and plasticity in various T cell functions and provides alternative views on their involvement in autoimmune and inflammatory diseases.