Type II collagen-reactive T cell (CII-reactive T cell)

Type II collagen-reactive T cells are a specialized population of CD4+ T lymphocytes that recognize epitopes of Type II collagen (CII), the predominant structural protein in joint cartilage (NIH, 2021). These cells are central to the pathogenesis of autoimmune arthritis, particularly rheumatoid arthritis (RA), where they are activated by CII peptides presented by specific MHC class II molecules such as HLA-DRB1*04 (NIH, 2012). Upon activation, these autoreactive T cells infiltrate the synovial membrane and secrete pro-inflammatory cytokines, including interferon-gamma (IFN-gamma) and interleukin-17 (IL-17), which drive chronic inflammation and joint destruction (MDPI, 2023). Therapeutic strategies targeting these cells focus on restoring immune tolerance to prevent the progression of joint damage. Experimental approaches include tolerogenic vaccines, such as MHC-peptide complexes (e.g., Aq-galCOL2) and altered peptide ligands (APLs), which aim to reprogram these T cells into a regulatory phenotype or induce anergy (PNAS, 2023; NIH, 2001). While conventional disease-modifying antirheumatic drugs (DMARDs) like methotrexate and biologics like abatacept provide broad T-cell modulation, therapies specifically directed at CII-reactive T cells offer a more precise approach to halting the autoimmune response in RA (Frontiers, 2022).

Other names

Collagen type II-specific T cellCII-specific T cellAutoreactive T cell (collagen-specific)Cartilage-specific T cell

Induction of immune tolerance, inhibition of T-cell activation and proliferation, modulation of cytokine profiles (shifting from Th1/Th17 to Treg phenotypes), and TCR-directed immune regulation.