Infiltratinglymphocytes in the inflamed pancreas were rare and mostly identified as non-Tcells (Supplementary Fig. 3A).Functionally, the absence of T and B lymphocytes inRag1−/− mice did not alter IL-17A-inducedgranulopoesis, neutrophil mobilization and aggregation in the pancreas (Supplementary Fig. 3A–D).IL-17A-induced pancreatitis thereby constitutes an inflammatory process notinstigated by the adaptive immune system. The gene discussed is IL17A; the disease is pancreatitis.