GSE173642
CD127+CD94+ innate lymphoid cells expanded in Crohn's disease patients highly express granulysin and perforin
Controversy in the identity and distinction of helper ILC1s and NK cells exist due to overlapping markers and the use of different gating strategies by distinct groups. Recently we identified cytotoxic ILC3s characterized by expression of CD94. Here we analyzed the full spectrum of CD127+ ILCs and NK cells in intestinal lamina propria from healthy donors and Crohn's disease patients and identified two populations of CD127+CD94+ ILCs, designated A and B that could be distinguished on expression of CD117, CD18 and cytotoxic molecules. Population B highly expressed granulysin, a cytotoxic molecule linked to bacterial lysis and/or chemotaxis of monocytes. Granulysin protein was amply secreted by population B cells upon stimulation with IL-15. Activation of population B in the presence of TGF-ß strongly reduced the expression of cytotoxic effector molecules of population B. Strikingly, samples from individuals that suffer from active Crohn disease displayed dramatically enhanced frequencies of granulysin expressing effector CD127+CD94+ ILCs compared to non-inflamed controls. Overall design: Single cell sequencing of human ILC from the gut of Crohn's disease patients