CD19蛋白;B-Lymphocyte Antigen CD19; B-Lymphocyte Surface Antigen B4; Differentiation Antigen CD19; T-Cell Surface Antigen Leu-12; CD19

Human

Human Cells

Lyophilized from a 0.2 μm filtered solution of 20mM PB,150mM NaCl,1%BSA,0.05%NaN3,pH 7.4.

Lyophilized protein should be stored at < -20°C, though stable at room temperature for 3 weeks. Reconstituted protein solution can be stored at 4-7°C for 2-7 days. Aliquots of reconstituted samples are stable at < -20°C for 3 months.

PEEPLVVKVEEGDNAVLQCLKGTSDGPTQLTWSRESPLKPFLKLSLGLPGLGIHMRPLAIWLFI FNVSQQMGGFYLCQPGPPSEKAWQPGWTVNVEGSGELFRWNVSDLGGLGCGLKNRSSEGPSSPSG KLMSPKLYVWAKDRPEIWEGEPPCLPPRDSLNQSLSQDLTMAPGSTLWLSCGVPPDSVSRGPLSW THVHPKGPKSLLSLELKDDRPARDMWVMETGLLLPRATAQDAGKYYCHRGNLTMSFH

C-Fc

Greater than 80% as determined by reducing SDS-PAGE.

Less than 0.1 ng/μg (1 IEU/μg) as determined by LAL test.

Always centrifuge tubes before opening. Do not mix by vortex or pipetting. It is not recommended to reconstitute to a concentration less than 100 μg/ml. Dissolve the lyophilized protein in ddH2O. Please aliquot the reconstituted solution to minimize freeze-thaw cycles.

CD19 is a single-pass type I membrane protein containing 2 Ig-like C2-type (immunoglobulin-like) domains. CD19 is expressed on follicular dendritic cells and B cells. In fact, it is present on B cells from earliest recognizable B-lineage cells during development to B-cell blasts but is lost on maturation to plasma cells. CD19 primarily acts as a B cell co-receptor in conjunction with CD21 and CD81. Upon activation, the cytoplasmic tail of CD19 becomes phosphorylated, which leads to binding by Src-family kinases and recruitment of PI-3 kinase. CD19 Assembles with the antigen receptor of B lymphocytes in order to decrease the threshold for antigen receptor-dependent stimulation. Defects in CD19 are the cause of immunodeficiency common variable type 3 (CVID3) which is a primary immunodeficiency characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen.

P15391