CD4 and colitis: The peptidoglycan extracted from probiotic bacteria demonstrated in vitro and in vivo anti-cancer effect [114, 115], in vivo immunomodulatory activity (peptidoglycan from L. rhamnosus CRL1505 significantly improved lung CD3+CD4+IFN-γ+, and CD3+CD4+IL-10+ T cells as well as CD11c+SiglecF+IFN-β+ alveolar macrophages with the consequent increases of IFN-γ, IL-10, and IFN-β in the respiratory tract) [112, 116], in vivo anti-inflammatory effect in a colitis mouse model [117].