IL6 and Autoimmunity: IL-6 can be rapidly induced and expressed in large quantities under the conditions of infection and autoimmunity and plays a key role in host defense by stimulating various cell populations (including promoting cytotoxic T cell differentiation, T cell population expansion and activation, and B cell differentiation).215 However, in addition to immune-stimulating effects, IL-6 can also lead to immunosuppression and TIE, most of which are mediated through the IL-6/JAK2/STAT3 signaling pathway.