Invitrogen™ CD43 Monoclonal Antibody (SP55)

CD43, also known as leukosialin or sialophorin, is a transmembrane mucin-like protein characterized by a high negative charge. It is expressed on the surface of most hematopoietic cells, excluding resting B lymphocytes. CD43 serves both adhesive and anti-adhesive functions, contributing to a repulsive barrier that can interfere with cellular adhesion while also promoting leukocyte aggregation in certain contexts. CD43 is involved in the activation of T cells, B cells, NK cells, and monocytes. Its expression decreases upon activation due to proteolytic processing. The counter-receptor for CD43 is CD169/SIGLEC-1, which is expressed on macrophages. CD43 interacts with actin-binding proteins ezrin and moesin, playing a regulatory role in remodeling T-cell morphology and regulating cell-cell interactions during lymphocyte traffic. It enhances LFA-1 adhesiveness while counteracting LFA-1 induction via other receptors. CD43 signaling induces the functionally active tumor suppressor p53 protein, but in cases of p53 and ARF deficiency, it can promote tumor proliferation and viability. CD43 is an important modulator of leukocyte functions, with dysfunctions associated with diseases such as Wiscott-Aldrich Syndrome and Adenoid Basal Cell Carcinoma.