Major Histocompatibility Complex Class II-Type II Collagen Peptide Complex (MHCII-CII complex)

The Major Histocompatibility Complex Class II-Type II Collagen (MHCII-CII) peptide complex is a pivotal immunological target in the study and treatment of Rheumatoid Arthritis (RA). This complex forms when antigen-presenting cells (APCs) process Type II collagen—the primary protein in articular cartilage—and present its immunodominant epitopes (such as CII 259-273) via MHC Class II molecules to T-cell receptors (Rosloniec et al., 1997, Journal of Immunology). In the context of Peyer's patches in the gut, the presentation of these epitopes following oral administration of collagen is a key mechanism for inducing oral tolerance. This process promotes the generation of regulatory T cells (Tregs) that migrate systemically to suppress the autoimmune attack on joints by secreting anti-inflammatory cytokines (Backlund et al., 2002, PNAS). Therapeutic interventions, such as oral collagen supplementation, aim to exploit this natural tolerogenic pathway to restore immune homeostasis in patients with chronic inflammatory joint diseases (Nagler-Anderson et al., 1986, PNAS).

Other names

HLA-DR-CII complexMHC-II/CII259-273 complexCollagen type II-MHC II complexMHCII-collagen epitope complexShared epitope-CII complex

Induction of oral tolerance through the presentation of collagen epitopes by APCs in gut-associated lymphoid tissue, leading to the expansion of CD4+ CD25+ Foxp3+ regulatory T cells (Tregs) and the secretion of suppressive cytokines like TGF-beta and IL-10 (Weiner et al., 2011, Nature Reviews Immunology).