CD191. also known as CCR5 (C-C chemokine receptor type 5), is a G protein-coupled receptor expressed on immune cells, including T lymphocytes, macrophages, and dendritic cells. It plays a critical role in mediating chemotaxis and immune responses by binding to specific chemokines such as CCL3. CCL4. and CCL5. CD191/CCR5 gained significant attention due to its role as a co-receptor for HIV-1 entry into host cells. Certain HIV-1 strains utilize CCR5 alongside CD4 to infect target cells, making it a key therapeutic target. The discovery of the CCR5Δ32 mutation, which confers natural resistance to HIV-1 infection in homozygous individuals, further highlighted its biological importance.
CD191 antibodies are tools used to study CCR5 expression, function, and signaling in immune regulation, inflammation, and viral pathogenesis. They enable researchers to block or detect CCR5 in experimental models, aiding in understanding its involvement in diseases like HIV/AIDS, autoimmune disorders, and cancers. Therapeutic anti-CCR5 antibodies, such as those explored in HIV treatment, aim to inhibit viral entry or modulate immune responses. Additionally, CCR5 antagonists like maraviroc, a small-molecule drug, have been developed based on insights from antibody studies. Beyond HIV, CD191 antibodies are investigated in contexts like cancer immunotherapy, where CCR5 blockade may reduce metastasis or enhance anti-tumor immunity. However, CCR5's dual roles in immune defense and pathology necessitate careful targeting to avoid unintended immunosuppression. Overall, CD191 antibodies remain vital for both basic research and the development of therapies targeting CCR5-mediated pathways.