Human P-selectin ELISA Kit (48-well)

• Aluminium pouches with a Microwell Plate coated with antibody to human P-Selectin (8x6)
• 2 vials human P-Selectin Standard lyophilized, 4000 pg/ml upon reconstitution
• 2 vials concentrated Biotin-Conjugate anti-human P-Selectin antibody
• 2 vials Streptavidin-HRP solution
• 4 bottle Standard /sample Diluent
• 1 bottle Biotin-Conjugate antibody Diluent
• 1 bottle Streptavidin-HRP Diluent
• 1 bottle Wash Buffer Concentrate 20x (PBS with 1% Tween-20)
• 1 vial Substrate Solution
• 1 vial Stop Solution
• 4 pieces Adhesive Films
• package insert

P-Selectin (GMP-140, LECAM-3, PADGEM, CD62, CD62P) is a cell surface glycoprotein that plays a critical role in the migration of lymphocytes into tissues . It is found constitutively in a pre-formed state in the Weibel-Palade bodies of endothelial cells and in the alpha granules of platelets . This stored P-Selectin is mobilized to the cell surface within minutes in response to a variety of inflammatory or thrombogenic agents . The mobilized P-Selectin is apparently present on the cell surface for only a few minutes after which it is recycled to intracellular compartments . Additional evidence indicates that transcription of P-Selectin mRNA can be activated in the endothelium by treatment with inflammatory mediators .P-Selectin consists of an NH2-terminal lectin type C domain, an EGF-like domain, nine complement control domains, a transmembrane domain, and a short cytoplasmic domain . Mouse P-Selectin shows a similar organization of functional domains and an overall sequence identity of approximately 73% . However, mouse P-Selectin contains only eightcomplement control domains, suggesting that the absolute number of these domains is not crucial for function . The molecular weight predicted from the cDNA for P-Selectin is approximately 86,000 . The observed molecular weight on reducing SDS-PAGE,however, is approximately 140,000 .

Evidence indicates that P-Selectin is involved in the adhesion of myeloid cells, as well as B cells and a subset of T cells, to activated endothelium . P-Selectin is also involved in the adhesion of platelets to monocytes and neutrophils, playing a central role in neutrophil accumulation within thrombi . The adhesion of leukocytes and neutrophils to the endothelium is initiated by weak interactions that produce a characteristic Â?rollingÂ? motion of the leukocytes and neutrophils on the endothelial surface . P-Selectin, acting in cooperation with L-Selectin, is implicated in the mediation of these initial interactions . Stronger interactions, probably involving E-Selectin, follow the initial interactions, leading eventually to extravasation through the blood vessel walls into lymphoid tissues and to sites of inflammation . The tetrasaccharide sialyl Lewisx (sLex) has been identified as a ligand for both P- and E-Selectin, but P-, E- and L-Selectin can all bind sLex and sLea under appropriate conditions . P-Selectin also reportedly binds selectively to a 160 kDa glycoprotein present on mouse myeloid cells, and to a glycoprotein on human myeloid cells, blood neutrophils, monocytes, and lymphocytes termed P-Selectin glycoprotein ligand-1 (PSGL-1), a ligand that also can bind E-Selectin . P-Selectin-mediated rolling of leukocytes can be completely inhibited by a monoclonal antibody specific for PSGL-1, suggesting that even though P-Selectin can bind to a variety of glycoproteins under in vitro conditions, it is likely that physiologically important binding is more limited .

P-Selectin is found in the plasma of normal individuals at ng/mL concentrations . Circulating P-Selectin appears to be slightly smaller than native P-Selectin. An alternatively spliced mRNA encoding a form of human P-Selectin lacking the transmembrane anchoring domain has been reported for both megakaryocytes and endothelial cells , and evidenc suggests that the majority of circulating soluble P-Selectin arises in this manner . A number of studies have reported that levels of soluble P-Selectin in biological fluids may be elevated in subjects with a variety of pathological conditions .