B-lymphocyte antigen CD19, also known as CD19 molecule (Cluster of Differentiation 19), B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12 and CVID3 is a transmembrane protein that in humans is encoded by the gene CD19.

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.

The CD19 antigen (aka B-lymphocyte antigen CD19 or Cluster of Differentiation 19) plays an important role in clinical oncology. It’s a protein found on the surface of B-cells, a type of white blood cell. Since CD19 is a hallmark of B-cells, the protein has been used to diagnose cancers that arise from this type of cell - notably B-cell ...

Mar 30, 2025 · CD19 (CD19 Molecule) is a Protein Coding gene. Diseases associated with CD19 include Immunodeficiency, Common Variable, 3 and Common Variable Immunodeficiency. Among its related pathways are Constitutive Signaling by Aberrant PI3K in Cancer and PIP3 activates AKT signaling.

CD19 is a 95 kDa transmembrane glycoprotein that belongs to the immunoglobulin superfamily and is expressed on B cells throughout most stages of B-cell differentiation. It forms a signal transduction complex and is commonly found in B cell–derived malignancies and …

CD19 expression is maintained in B-lineage cells that have undergone neoplastic transformation, and therefore CD19 is useful in diagnosis of leukemias and lymphomas using monoclonal antibodies (mAbs) and flow cytometry.

May 14, 2021 · CD19 structure and signaling Clinical features Defects in CD19 cause immunodeficiency common variable type 3 ( OMIM #613493 ), characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen

Here in this review, we summarize the latest development on the major functions of CD19 as both positive and negative regulator of BCR signaling in different situations and highlight the correlation and mechanisms of disturbed CD19 expression with autoimmune diseases and B cell lymphomas.

CD19+ B cells are a type of white blood cell that plays a fundamental role in the immune system's ability to respond to infections and produce antibodies. When the percentage of CD19+ B cells is lower than normal, it can suggest several underlying factors or conditions, including:

Nov 5, 2015 · In vivo, CD19 deficiency impaired, and CD19 overexpression enhanced, LYN kinase activity. CD19 thus functions as a specialized adaptor protein for the amplification of Src family kinases that is crucial for intrinsic and antigen receptor-induced signal transduction.