Rabbit anti-Human CD19 Polyclonal Antibody

Uniprot Id

P15391

Target Species

Human

Target Name

CD19

Target Full Name

B-lymphocyte antigen CD19

Target Function

Functions as coreceptor for the B-cell antigen receptor complex (BCR) on B-lymphocytes. Decreases the threshold for activation of downstream signaling pathways and for triggering B-cell responses to antigens. Activates signaling pathways that lead to the activation of phosphatidylinositol 3-kinase and the mobilization of intracellular Ca(2+) stores. Is not required for early steps during B cell differentiation in the blood marrow. Required for normal differentiation of B-1 cells. Required for normal B cell differentiation and proliferation in response to antigen challenges. Required for normal levels of serum immunoglobulins, and for production of high-affinity antibodies in response to antigen challenge.

Target Involvement

Immunodeficiency, common variable, 3 (CVID3)

Target Subcellular Location

Cell membrane; Single-pass type I membrane protein. Membrane raft; Single-pass type I membrane protein.

Target Tissue Specificity

Detected on marginal zone and germinal center B cells in lymph nodes. Detected on blood B cells (at protein level).

Target Research Area

Immunology

Target Synonyms

CD19; B-lymphocyte antigen CD19; B-lymphocyte surface antigen B4; Differentiation antigen CD19; T-cell surface antigen Leu-12; CD antigen CD19

Target Background

This gene encodes a member of the immunoglobulin gene superfamily. Expression of this cell surface protein is restricted to B cell lymphocytes. This protein is a reliable marker for pre-B cells but its expression diminishes during terminal B cell differentiation in antibody secreting plasma cells. The protein has two N-terminal extracellular Ig-like domains separated by a non-Ig-like domain, a hydrophobic transmembrane domain, and a large C-terminal cytoplasmic domain. This protein forms a complex with several membrane proteins including complement receptor type 2 (CD21) and tetraspanin (CD81) and this complex reduces the threshold for antigen-initiated B cell activation. Activation of this B-cell antigen receptor complex activates the phosphatidylinositol 3-kinase signalling pathway and the subsequent release of intracellular stores of calcium ions. This protein is a target of chimeric antigen receptor (CAR) T-cells used in the treatment of lymphoblastic leukemia. Mutations in this gene are associated with the disease common variable immunodeficiency 3 (CVID3) which results in a failure of B-cell differentiation and impaired secretion of immunoglobulins. CVID3 is characterized by hypogammaglobulinemia, an inability to mount an antibody response to antigen, and recurrent bacterial infections. Alternative splicing results in multiple transcript variants encoding distinct isoforms.