Human B-Lymphocyte Antigen CD19 (CD19) Protein

Background

CD19 is a transmembrane glycoprotein primarily expressed on B cells, a subset of white blood cells responsible for producing antibodies and mediating humoral immunity. CD19 plays a crucial role in B-cell development, activation, and differentiation, making it a critical marker and regulator in the immune response. It is part of the immunoglobulin superfamily and serves as a coreceptor for the B-cell receptor (BCR), amplifying BCR-mediated signaling, which is essential for proper immune function. CD19 is expressed throughout most stages of B-cell development, from the pro-B cell stage in the bone marrow to mature B cells in peripheral tissues. This widespread expression makes it a reliable marker for identifying B cells in research and clinical settings, and it is often targeted in therapeutic strategies aimed at modulating B-cell function, such as in CAR-T cell therapy for treating B-cell malignancies.