CD19 is a 95kD type I transmembrane glycoprotein, also called B4. It is part of the immunoglobulin superfamily that is expressed by B cells (from Pro-B cells to B blastoid cells, non-existent from plasma cells) and follicular dendritic cells.
CD19 can be found in B cell growth inactivation and differentiation. CD19 is a part of a complex that includes CD21 (CR2) as well as CD81 (TAPA-1) and serves in the role of the BCR co-receptor. You can know more about CD19 antibodies via https://www.bosterbio.com/anti-cd19-picoband-trade-antibody-a00154-4-boster.html.
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CD19 is part of the immunoglobulin superfamily. It has the presence of two Ig similar domains. The CD19 molecules are expressed on all of the peripheral B cells according to the expression of lambda or kappa light chains.
CD19 is thought as if it is expressed by myeloid lymphoma cells, specifically those belonging to monocytic lineage. Leukemia study of phenotypes has shown that the earliest and broadest B cell-specific antibody is CD19 antigen.
Its receptor CD19 is an essential regulatory function for benign and normal B cell proliferative capacity and is found in all precursor leukemias of B cells. Lymphocytes multiply and change shape in reaction to various levels of antigens.
The capacity of B cells to react in a particular and sensitive way to various antigens is made possible by the use of low-affinity receptors.
CD19 is a cell-surface molecule that binds to the antigen receptors of B lymphocytes to reduce the threshold of stimulation by the antigen receptor.
In addition to being a signal-amplifying receptor for B-cell receptor (BCR), CD19 can also act independently of BCR co-ligation and is a key regulator on which multiple signaling pathways are connected.