Cd19-iCre Mouse

The cluster of differentiation 19 (CD19) gene encodes a member of the immunoglobulin gene superfamily, whose expression is restricted to B lymphocytes and is a marker of pre-B cells. In humans, CD19 is expressed on all cells of the B lymphoid lineage except plasma cells and follicular dendritic cells. CD19 acts as an adapter protein to recruit cytoplasmic signaling proteins to the membrane and acts within the CD19/CD21 complex to lower the threshold of the B cell receptor signaling pathway. The protein is a biomarker for B lymphocyte development and lymphoma diagnosis and may serve as a target for leukemia immunotherapy. Mutations in this gene are associated with common variable immunodeficiency 3 (CVID3) disease, which is characterized by hypogammaglobulinemia, failure to mount an antibody response to antigen, and recurrent bacterial infections, and certain loss-of-function mutations in this gene also fails B cell differentiation and impaired immunoglobulin secretion.

Cd19-iCre mice are generated by knocking the P2A-iCre cassette into the endogenous Cd19 gene, enabling expression of iCre (a codon-optimized Cre with higher recombination activity) driven by Cd19 gene regulatory elements. When crossed with mice containing loxP sites, their offspring undergo Cre recombinase-mediated recombination between loxP sites specifically in B lymphoid lineage cells.