interleukin37 inhibits the imbalance between t helper 17 cells and regulatory t cells in hand foot and mouth disease the aim of this study was to explore the role of interleukin37 il37 in imbalance of t helper th17regulatory t cells tregs in hand foot and mouth disease hfmd the proportions of cd4 il17a th17 cells and cd4 cd25foxp3 tregs in peripheral blood or peripheral blood mononuclear cells pbmcs from hfmd patients and healthy controls were measured by fluorescence activated cell sorter the level of il37 il10 il17a il23 and transforming growth factor 1 tgf1 in serum or pbmcs of hfmd patients and control subjects were detected using enzymelinked immunosorbent assay results showed that th17 cells proportion and il17a and il23 levels were highly increased whereas tregs proportion and il10 and tgf1 levels were significantly decreased in hfmd patients moreover il37 stimulation elevated tregs proportion but reduced th17 cell proportion in subjects with hfmd on the contrary we found methylprednisolone pulse therapymethylprednisolone combinated with intravenous gamma globulin inhibits th17treg imbalance through upregulation of il37 in hfmd in conclusion il37 inhibits the imbalance of th17tregs in hfmd