HLA-DR2

HLA-DR2 is a human leukocyte antigen serotype within HLA-DR serogroup. The serotype is determined by the antibody recognition of alleles at HLA-DRB1 locus. HLA-DR2 and HLA-DR51 are associated with multiple sclerosis, narcolepsy, and systemic lupus erythematosus.

Structure and Function

HLA-DR2 is a cell surface receptor that plays a crucial role in the immune system. It is part of the major histocompatibility complex (MHC) class II, a group of proteins that present antigens to T cells to initiate an immune response. HLA-DR2 is composed of two non-covalently associated chains, α and β, encoded by the genes HLA-DRA and HLA-DRB1 respectively.

Associations with Diseases

HLA-DR2 has been associated with several autoimmune diseases. It is strongly associated with multiple sclerosis, a chronic disease that affects the central nervous system. Studies have shown that individuals with the HLA-DR2 allele have a higher risk of developing multiple sclerosis.

HLA-DR2 is also associated with narcolepsy, a neurological disorder characterized by excessive daytime sleepiness and abnormal REM sleep. Research has indicated that nearly all individuals with narcolepsy who have cataplexy are positive for HLA-DR2.

In addition, HLA-DR2 is linked with systemic lupus erythematosus (SLE), an autoimmune disease in which the body's immune system mistakenly attacks healthy tissue. The presence of the HLA-DR2 allele has been found to increase susceptibility to SLE.

See Also

• Human leukocyte antigen
• Major histocompatibility complex
• Multiple sclerosis
• Narcolepsy
• Systemic lupus erythematosus