Innate-Like and Conventional T Cell Populations from Hemodialyzed and Kidney Transplanted Patients Are Equally Compromised

Clinicians are well aware of existing pharmacologically-induced immune deficient status in kidney-transplanted patients that will favor their susceptibility to bacterial or viral infections. Previous studies indicated that advanced Stage 4–5 Chronic Kidney Disease might also be regarded as an immune deficiency-like status as well, even though the mechanisms are not fully understood. Here, we analyzed the ex vivo frequency and the functional properties of both conventional and innate-like T (ILT) lymphocyte subsets in the peripheral blood of 35 patients on hemodialysis, 29 kidney transplanted patients and 38 healthy donors. We found that peripheral blood cell count of ILT cells, as iNKT (invariant Natural Killer T) and MAIT (mucosal-associated invariant T), were significantly decreased in hemodialyzed patients compared to healthy controls. This deficiency was also observed regarding conventional T cells, including the IL-17-producing CD4⁺ Th17 cells. Pertaining to regulatory T cells, we also noticed major modifications in the global frequency of CD4⁺CD25⁺Foxp3⁺ T lymphocytes, including the resting suppressive CD45RA⁺Foxp3^lo and activated suppressive CD45RA⁻Foxp3^hi T cell subpopulations. We found no significant differences between the immune status of hemodialyzed and kidney-transplanted subjects. In conclusion, we demonstrated that both ILT and conventional T cell numbers are equally impaired in hemodialyzed and kidney-transplanted patients.