CD4 and inflammatory skin disease: In addition, depletion of CD4+ immune cells has been never connected to imbalanced SC homeostasis in the skin, but rather results in inflammatory skin disease (e.g. in DiGeorge syndrome40), decreased susceptibility to skin tumors (e.g. CD4KO mice15–17) or increased susceptibility to papillomavirus-induced warts (e.g. human CD4 deficiency41–43).