Mouse Anti-Human CD19 Antibody (HIB19)

CD19, also known as B-lymphocyte antigen CD19 or B-Lymphocyte Surface Antigen B4, is a 95 kDa type I transmembrane glycoprotein that belongs to the immunoglobulin superfamily and is encoded by the CD19 gene. It is primarily expressed on all B lineage cells, from early pro-B cells to plasma cells, and plays a crucial role in B cell development, activation, and signaling. As a co-receptor, CD19 enhances signaling through the B cell receptor (BCR) complex, lowering the threshold for B cell activation and promoting B cell proliferation and differentiation. It forms a complex with CD21, CD81, and other proteins, which helps in the recognition of antigens tagged with complement and amplifies BCR signaling. CD19 is also a biomarker for B cell-related diseases and a target for immunotherapies, including monoclonal antibodies and CAR-T cell therapies, due to its consistent expression on B cells and B cell malignancies.