While Th2 cytokines such as IL-4, IL-13, IL-33, and TSLP dominated the inflammatory landscape in AD and bullous pemphigoid, Th1 and Th17 immune responses, primarily mediated by IFN-γ and IL-17, characterized psoriasis, lichen planus, and specific forms of GvHD. The gene discussed is IL17A; the disease is graft versus host disease.