Porcine platelet von Willebrand antigen II (vW AgII): inhibitory effect on collagen-induced aggregation and comparative distribution with human platelets.
Von Willebrand factor (vWF) is synthesized by human endothelial cells and megakaryocytes as a large precursor, the pre-provWF, which is finally cleaved into the propolypeptide of vWF (pp-vWF) and the mature vWF. We have purified in parallel the pp-vWF and the GP IIb-IIIa from porcine platelets. The N-terminus comparative analysis of porcine pp-vWF with respect to other species revealed more than a 75% and 65% homology with the bovine and human pp-vWF, respectively. Purified pp-vWF inhibited collagen-induced platelet aggregation in porcine platelet rich plasma (PRP) and specifically binds to collagen. Polyclonal antibody pabBp19 against the purified protein was prepared and characterized by ELISA, Western-blot and immunocytochemistry. The distribution of pp-vWF in soluble and membrane fractions from pig platelets has been performed by immunolabeling detection. pabBp19 did not blot human platelet lysates but human pp-vWF was detectable using the antibody Frieda 013091. Cell distribution and quantification studies of human and porcine platelet pp-vWF showed that the protein exists in the soluble and membrane fractions and its pattern is similar in both species.
Royo
T
T
Cardiovascular Research Center, CSIC-Hospital de la Santa Creu i Sant Pau-UAB, Barcelona, Spain.
Vidal
M
M
Badimon
L
L
D000595:Amino Acid Sequence; D000818:Animals; D000941:Antigens / Q000235:genetics / Q000302:isolation & purification* / Q000494:pharmacology*; D001792:Blood Platelets / Q000737:chemistry / Q000502:physiology*; D002417:Cattle; D003094:Collagen / Q000494:pharmacology*; D006801:Humans; D008969:Molecular Sequence Data; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology*; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000235:genetics; D016415:Sequence Alignment; D013552:Swine; D014841:von Willebrand Factor / Q000502:physiology
D000941:Antigens; D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; C029417:Von Willebrand antigen; D014841:von Willebrand Factor; D003094:Collagen