KIR2DL4
KIR2DL4: The Double-Edged Sword in Immunity
Description
KIR2DL4, a killer cell immunoglobulin-like receptor (KIR), is a key player in the human immune system, particularly in regulating the function of natural killer (NK) cells. NK cells are cytotoxic lymphocytes that play a crucial role in innate immunity, eliminating infected or cancerous cells.
KIR2DL4 is one of the inhibitory KIRs, meaning it suppresses NK cell activity. It binds to specific human leukocyte antigen (HLA) class I molecules, which are expressed on the surface of all nucleated cells. This binding prevents NK cells from attacking healthy cells.
Associated Diseases
KIR2DL4 has been linked to several diseases and conditions, including:
1. Viral Infections: KIR2DL4 deficiency has been associated with increased susceptibility and severity of viral infections, such as cytomegalovirus (CMV) and Epstein-Barr virus (EBV).
2. Cancer: KIR2DL4 expression levels have been implicated in various cancers, including breast cancer, lung cancer, and leukemia. Low KIR2DL4 levels may allow cancer cells to evade NK cell killing.
3. Autoimmune Diseases: KIR2DL4 has a potential role in the development of autoimmune diseases, where the immune system mistakenly attacks its own tissues. Specific KIR2DL4 haplotypes have been associated with increased risk for autoimmune diseases such as multiple sclerosis (MS) and rheumatoid arthritis (RA).
Did you Know ?
- Approximately 70% of the human population carries one or more copies of the KIR2DL4 gene.
