Galactose-specific lectin from Viscum album as a mediator of aggregation and priming of human platelets.
Galactose-specific lectin from Viscum album (VAA) was found to induce aggregation of human platelets in a dose- and sugar-dependent manner. Small nonaggregating concentrations of VAA primed the response of platelets to known aggregants (ADP, arachidonic acid, thrombin, ristocetin, and A23187). VAA-induced platelet aggregation was completely reversible by addition of the sugar inhibitor lactose and the platelets from disrupted aggregates maintained the response to other aggregants. The lectin-induced aggregation of washed platelets was more resistant to metabolic inhibitors than thrombin- or arachidonic acid-dependent cell interaction. In contrast to the related galactose-specific lectin from Ricinus communis and the soy bean agglutinin, the lectin did not aggregate liposomes prepared from total platelet lipids, indicating different affinities of aggregation-mediating lectins to platelet glycolipids.
Samal
A B
AB
Department of Biophysics, Belarusian State University, Minsk, Belarus.
Gabius
H J
HJ
Timoshenko
A V
AV
D016718:Arachidonic Acid / Q000494:pharmacology; D001792:Blood Platelets / Q000737:chemistry; D004305:Dose-Response Relationship, Drug; D005690:Galactose / Q000378:metabolism*; D006017:Glycolipids / Q000302:isolation & purification; D006801:Humans; D007785:Lactose / Q000494:pharmacology; D037102:Lectins / Q000037:antagonists & inhibitors / Q000494:pharmacology; D008081:Liposomes; D008563:Membrane Lipids / Q000302:isolation & purification; D028321:Plant Preparations; D010940:Plant Proteins; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D054790:Ribosome Inactivating Proteins, Type 2; D013917:Thrombin / Q000494:pharmacology; D014118:Toxins, Biological / Q000378:metabolism / Q000494:pharmacology*
D006017:Glycolipids; D037102:Lectins; D008081:Liposomes; D008563:Membrane Lipids; D028321:Plant Preparations; D010940:Plant Proteins; D010975:Platelet Aggregation Inhibitors; D054790:Ribosome Inactivating Proteins, Type 2; D014118:Toxins, Biological; C009674:ribosome inactivating protein, Viscum; D016718:Arachidonic Acid; D013917:Thrombin; D007785:Lactose; D005690:Galactose