TDS | SDS

The SJ25C1 antibody reacts with human CD19, a 95 kDa glycoprotein which acts as a co-receptor, along with CD21 (CR2), CD81 (TAPA-1) and CD225 (Leu13), in support of the functional B cell receptor (BCR). This complex provides antigen-specific recognition and subsequent activation of B cells to proliferate and differentiate into antibody-secreting cells (plasma cells) or memory B cells, which are crucial for secondary antigen encounter. Upon activation and tyrosine phosphorylation, the CD19 molecule can provide an anchor for cytoplasmic signaling proteins such as GRB2, SOS or PLCG2. CD19 is a lineage-differentiation marker, as its expression is detectable at the earliest B cell stages, through development, and is finally lost upon transition to mature plasma cells.

The SJ25C1 antibody is widely used as a phenotypic marker for CD19 expression on B cells, as well as on dendritic cell subsets.