Unconventional T cells are a wide range and not a well-known group of comparatively rare lymphocytes different from traditional CD4+ and CD8+T cells, which primarily recognize antigens in the absence of classical limitation through the major histocompatibility complex (MHC). This rare group of cells includesmucosal-associated invariant T cells, natural killer T cells, γδ T cells, and others. These cells can have either protective or pathogenic roles in various inflammatory and autoimmune conditions related to acute and chronic kidney disease. 

These unconventional cells assume either a protective or pathogenic role in many inflammatory and autoimmune responses in the kidney. Clinical studies have also revealed that some T cells are potential therapeutic targets and prognostic and diagnostic biomarkers. 

In the case of microbial pathogens, the response of human Vγ9Vδ2 T cells and MAIT cells has consequences in early diagnosis, risk gradation, and targeted therapy of peritoneal dialysis-related peritonitis. In addition, these cells can also be used for immune monitoring and adoptive immunotherapy in kidney transplant recipients. Besides, NKT, MAIT, orγδ T-cells are also involved in the immunopathology of IgA nephropathy and in murine models of glomerulonephritis, ischemia-reperfusion injury, and kidney transplantation. These cells may be relevant for allograft tolerance and in kidney protection in lupus nephritis or crescentic glomerulonephritis. 

Reference: Kaminski H, Couzi L, Eberl M. Unconventional T cells and kidney disease. Nature reviews Nephrology. 2021. DOI: https://doi.org/10.1038/s41581-021-00466-8