TGFB1 and systemic sclerosis: For example, an increase in the frequency of MCT (tryptase+/chymase−) cells compared to MCTC (tryptase+/chymase+) cells has been described in SSc skin lesions [90], and other studies have shown that SSc is associated with an increase in the number of dermal mast cells expressing transforming growth factor (TGF)-β1/2 [88] or interleukin (IL)-17A [91].