Expansion of Group 2 Innate Lymphoid Cells in Patients with End-Stage Renal Disease and Their Clinical Significance.

Group 2 innate lymphoid cells (ILC2s) play an important role in the control of tissue inflammation and homeostasis. However, the role of ILC2s in patients with end-stage renal disease (ESRD) has never been illustrated. In this study, we investigated ILC2s in ESRD patients and their clinical significance. Results showed that the frequencies and absolute numbers of ILC2s, not group 1 innate lymphoid cells or innate lymphoid cell precursors, were significantly elevated in the peripheral blood of ESRD patients when compared with those from healthy donor controls. Moreover, ILC2s from ESRD patients displayed enhanced type 2 cytokine production and cell proliferation. Plasma from ESRD patients significantly increased ILC2 levels and enhanced their effector function after in vitro treatment. The expression of phosphorylation of STAT5 in ILC2s, as well as the amounts of IL-2 in plasma, were increased in ESRD patients when compared with those from healthy donors. Clinically, ESRD patients with higher ILC2 frequencies displayed lower incidence of infectious complications during a mean of 21 month follow-up study. The proportions of ILC2s were negatively correlated with the prognostic biomarkers of chronic kidney disease, including serum parathyroid hormone, creatinine, and phosphorus, whereas they were positively correlated with serum calcium. These observations indicate that ILC2s may play a protective role in ESRD.