CD19 is a biomarker for normal and neoplastic B cells, as well as follicular dendritic cells. CD19 is critically involved in establishing intrinsic B cell signaling thresholds through modulating both B cell receptor-dependent and independent signaling.

These decisions are tightly regulated through B cell receptor (BCR) interactions and signaling. The presence of a functional BCR is necessary during antigen-dependent differentiation and for continued survival in the peripheral immune system. [14] Essential to the functionality of a BCR is the presence of CD19. [20]

Dec 2, 2007 · CD19 is a B cell–specific coreceptor expressed at early stages of B cell development. It has been shown to enhance signaling through the BCR. In the plasma membrane of B cells, CD19...

CD19 is a co-stimulatory surface protein expressed exclusively on B cells and serves to reduce the threshold for signalling via the B-cell receptor (BCR). Co-ligation of CD19 with the BCR synergistically enhances mitogen-activated protein (MAP) kinase activity, calcium release and …

CD19 is the essential signaling subunit of a multi-component co-receptor complex that functions in concert with the BCR to execute the cellular response to antigen.

CD19 positively regulates B cell activation, augmenting signals delivered through the BCR complex. In contrast, CD32b contains an ITIM and negatively regulates BCR signaling.

Jul 1, 2001 · The CD19/CD21 complex is an important coreceptor that plays a critical role in B cell responses to T cell-dependent Ags (1). The CD19/CD21 complex functions synergistically with the B cell Ag receptor (BCR) 2 to reduce the threshold for B cell activation.

In response to membrane-bound ligand stimulation, antigen aggregation occurs in B cell antigen receptor (BCR) microclusters containing immunoglobulin (Ig) M and IgD that recruit the kinase Syk and transiently associate with the coreceptor CD19.

Dec 1, 2003 · In reconstituted myeloma cells, CD19 has been shown to be necessary for efficient BCR-mediated activation of Btk (55), most likely through the PI3-K pathway and the production of phosphatidylinositol-3,4,5-triphosphate in concert with Lyn-mediated phosphorylation of …

Jun 2, 2015 · CD19 is a B cell–specific molecule that serves as a major costimulatory molecule for amplifying B-cell receptor (BCR) responses. Biallelic CD19 gene mutations cause common variable immunodeficiency in human subjects.