IL13 and immune system disorder: Shimada et al recently proposed the “two-hit podocyte immune disorder” hypothesis.27–31 First, CD80 expression is induced in podocytes by circulating cytokines (such as interleukin 13), microbial products, or allergens.27–29 Then, due to regulatory T lymphocyte (Treg) dysfunction and/or impaired CD80 autoregulation, sustained podocyte injury results in INS.29–31 Treg cells are essential for maintaining homeostasis of the immune system.