Anti-CD19 Antibody

CD19 is a 95 kDa transmembrane glycoprotein belonging to the immunoglobulin superfamily, expressed on the surface of B lymphocytes from the pro-B cell stage through mature B-cell differentiation, but absent on plasma cells and most early lymphoid progenitors. This unconjugated rabbit polyclonal reagent from Antibodies.com targets the cytoplasmic domain of human CD19 and is supplied as a 100 µl aliquot suitable for western blot and immunohistochemistry workflows.

In flow cytometry and immunophenotyping, CD19 serves as the canonical pan-B-cell marker, widely used to identify B-cell populations in peripheral blood, bone marrow, and lymphoid tissue, and to characterize B-cell-derived malignancies including chronic lymphocytic leukemia, diffuse large B-cell lymphoma, and acute lymphoblastic leukemia. Researchers also rely on this target to study B-cell receptor signaling, as CD19 associates with the BCR complex and amplifies Src-family kinase activity through its cytoplasmic ITAM-like motif.

For western blot, the antibody can be used to detect endogenous CD19 in human B-cell lines such as Raji or Daudi, with detection typically performed on whole-cell lysates under reducing conditions. In immunohistochemistry, the reagent has been employed on formalin-fixed paraffin-embedded sections of tonsil and spleen, where it highlights follicular and mantle zone B cells while sparing T-cell regions. Each vial is shipped refrigerated; for long-term storage, aliquot and freeze at -20 °C to minimize freeze-thaw cycles and preserve reactivity.

This reagent is intended for research use only and should be handled as an in vitro laboratory reagent. Users are encouraged to validate the antibody in their own experimental system, as optimal dilutions can vary between applications and tissue types.