LP17759-9

CD19

Active

Descriptions

CD19 (Cluster of Differentiation 19), is a human protein encoded by the CD19 gene.
Lymphocytes proliferate and differentiate in response to various concentrations of different antigens. The ability of the B cell to respond in a specific, yet sensitive manner to the various antigens is achieved with the use of low-affinity antigen receptors. This gene encodes a cell surface molecule which assembles with the antigen receptor of B lymphocytes in order to decrease the threshold for antigen receptor-dependent stimulation.
CD19 is expressed on follicular dendritic cells and B cells. In fact, it is present on B cells from earliest recognizable B-lineage cells during development to B-cell blasts but is lost on maturation to plasma cells.
It primarily acts as a B cell co-receptor in conjunction with CD21 and CD81.
Upon activation, the cytoplasmic tail of CD19 becomes phosphorylated which leads to binding by Src-family kinases and recruitment of PI-3 kinase. Copyright Text is available under the Creative Commons Attribution/Share-Alike License. See http://creativecommons.org/licenses/by-sa/3.0/ for details. Source: Wikipedia, CD18

The CD19+ B cells are 95 kilo Dalton transmembrane glycoproteins and are comprised of a single transmembrane domain, a cytoplasmic C-terminus, and an extracellular N-terminus. It is a biomarker for normal and neoplastic B cells and for dendritic cells. CD19+ B cells regulate signaling thresholds by modifying B cell receptor dependent and independent signaling, functioning as a dominant piece of a multimolecular complex that resides on the mature B cell surface. The concentration of CD19 on the surface of B cells is tightly controlled throughout the cell's development, making it a very valuable biomarker for B cells. Mature B cells have three times the number of CD19 antigens than immature B cells, and when B cells differentiate into plasma cells, the expression of CD19 is lost. Patients who lack sufficient CD19 antigens have a lower response to transmembrane signals and weak T cell dependent antibody responses. CD19 is highly conserved and expressed in most B cell malignancies including acute lymphocytic leukemia, B cell lymphoma, and B cell leukemia. Efforts are in play to utilize CD19 antibodies for the treatment of lymphoma, leukemia, and autoimmune disorders. PMID: 23210908 Source: Regenstrief LOINC

Basic Part Properties

Part Name

CD19

Part Display Name

CD19

Part Type

Component (Describes the core component or analyte measured)

Created On

2000-05-04

Construct for LOINC Short Name

CD19

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