This Dsg3‐specific immune reaction was mediated only by a combination of T cells and B cells derived from Dsg3−/− mice but not perfectly achieved when either of the cell populations were derived from wild‐type mice, suggesting the necessity of T cell–B cell interaction and loss of immunological tolerance against Dsg3 in both populations for the development of the pemphigus phenotype in this animal model.39 This evidence concerns the gene DSG3 and pemphigus.