Type II collagen (CII) (CII)

Type II collagen (CII) is the primary structural protein of articular cartilage and serves as a major autoantigen in the development of rheumatoid arthritis (RA) (Trentham et al., 1993). The therapeutic concept involving "Gut-associated lymphoid tissue (GALT) immune epitopes recognizing type II collagen" refers to the induction of oral tolerance, a process where the ingestion of CII modulates the systemic immune response (Nagler-Anderson et al., 1986). When CII is orally administered, its specific epitopes are processed by antigen-presenting cells within the GALT, particularly in the Peyer's patches of the small intestine (Park et al., 2009). This interaction promotes the differentiation of regulatory T cells (Tregs), such as Th3 cells, which secrete anti-inflammatory cytokines like TGF-beta and IL-10 (Weiner et al., 2011). These Tregs subsequently migrate to the joints, where they recognize endogenous CII and suppress the localized inflammatory environment through a mechanism known as bystander suppression (Lugo et al., 2016). This approach is utilized by various investigational drugs and supplements, such as undenatured type II collagen (UC-II), to treat inflammatory joint diseases by leveraging the natural tolerogenic environment of the gut (Gencoglu et al., 2020).

Other names

Gut-associated lymphoid tissue immune epitopes recognizing type II collagenCollagen alpha-1(II) chainCOL2A1Cartilage collagenNative type II collagenUndenatured type II collagen

Induction of oral tolerance via the gut-associated lymphoid tissue (GALT), leading to the generation of regulatory T cells (Tregs) that suppress joint inflammation through bystander suppression.