**Background of BTNL2 Antibody**
Butyrophilin-like 2 (BTNL2), a member of the immunoglobulin superfamily, is a transmembrane protein implicated in immune regulation. Structurally, it shares homology with the B7 family of co-stimulatory molecules, featuring extracellular immunoglobulin-V-like and immunoglobulin-C-like domains. BTNL2 is primarily expressed in immune tissues and epithelial cells, notably in the gut, where it modulates T-cell responses. Studies suggest it acts as a co-inhibitory molecule, dampening T-cell activation and promoting regulatory T-cell function, thereby maintaining immune tolerance.
Genetic variations in *BTNL2* are linked to autoimmune and inflammatory diseases, including sarcoidosis, rheumatoid arthritis, and inflammatory bowel disease (IBD). Certain polymorphisms (e.g., rs2076530) are associated with increased disease susceptibility, highlighting its role in immune dysregulation.
BTNL2 antibodies are essential tools for investigating its expression, localization, and function. Monoclonal antibodies targeting specific epitopes enable detection in tissues (via immunohistochemistry) or immune cells (via flow cytometry). Researchers also use BTNL2 antibodies to explore its interaction with putative receptors and downstream signaling pathways, which remain partially characterized. Additionally, therapeutic potential is being explored, with antibodies designed to either block or enhance BTNL2 activity in autoimmune disorders or cancer immunotherapy. Challenges include clarifying its precise ligands and mechanisms, necessitating further functional studies.