Conversely, IL-17 has recently been shown to be involved in various autoimmune disorders. In PBC liver tissues, density of IL-17(+) CD4 lymphocytic infiltration (Th17) was higher than in healthy liver. Although enhanced density of Th17 cells is not specific to PBC, it is in line with the observation of the decreased number of Tregs and may illustrate the counterplay of Tregs and Th17 cells in PBC [203] .