The findings of a further study have indicated that compared with late-stage SSc patients and healthy controls, skin Tregs are more numerous in the skin epidermis and dermis of early SSc patients (183), whereas in patients with limited and diffuse SSc, the Tregs in skin lesions have been found to produce pro-fibrotic Th2 cytokines, such as IL-13 and IL-4 (138). Here, IL4 is linked to systemic sclerosis.