IL22 and graft versus host disease: It has further been noted that there may be a parallel between IL-22 deficiency in GVHD and the condition autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), in which antibodies have the ability to neutralize cytokines such as IL-22 (Kärner et al., 2013; Laakso et al., 2014).