This protein carries a human IgG1 Fc tag at the C-terminus. The protein has a calculated MW of 56.7 kDa. The protein migrates as 66-100 kDa under reducing (R) condition (SDS-PAGE) due to glycosylation.
No activity loss was observed after storage at: In lyophilized state for 1 year (4 °C), After reconstitution under sterile conditions for 3 months (-70 °C).
B-lymphocyte antigen CD19 (CD19) is also known as B-lymphocyte surface antigen B4, Differentiation antigen CD19 and T-cell surface antigen Leu-12, which is a single-pass type I membrane protein and contains two Ig-like C2-type (immunoglobulin-like) domains. CD19 forms a complex with CD21, CD81 and CD225 in the membrane of mature B cells. CD19 interacts with GRB2 and SOS when phosphorylated on Tyr-348 and/or Tyr-378. CD19 also interacts with PLCG2 when phosphorylated on Tyr-409. CD19 is an important pan B cell marker and co-stimulatory protein in humans and mice. CD19 is a hallmark differentiation antigen of the B cell lineage and positively regulates antigen receptor signal transduction in mature B cells. CD19 defines signaling thresholds for the Ag receptor as well as other cell surface receptors that regulate B lymphocyte selection, activation, and differentiation. Defects in CD19 are a cause of hypogammaglobulinemia.