Mouse Cluster of differentiation 19,CD19 ELI

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 (By similarity).

Activates signaling pathways that lead to the activation of phosphatidylinositol 3-kinase and the mobilization of intracellular Ca(2+) stores (PubMed:9382888, PubMed:12387743, PubMed:20101619).

Is not required for early steps during B cell differentiation in the blood marrow (PubMed:7542548, PubMed:7543183, PubMed:9317126).

Required for normal differentiation of B-1 cells (PubMed:7542548, PubMed:7543183, PubMed:12387743).

Required for normal B cell differentiation and proliferation in response to antigen challenges (PubMed:7542548, PubMed:9317126, PubMed:12387743).

Required for normal levels of serum immunoglobulins, and for production of high-affinity antibodies in response to antigen challenge (PubMed:7542548, PubMed:7543183, PubMed:12387743).

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