The platelet glycoprotein Ia-IIa-associated Br-alloantigen system is expressed by cultured endothelial cells.
To obtain information on the immunological relationship between the endothelial and platelet glycoprotein (GP)Ia-IIa (VLA-2) complex, we studied whether endothelial GPIa-IIa was able to express the platelet GPIa-IIa-associated Br-alloantigen system. Therefore, we tested antisera to both allelic forms of the Br system (Bra and Brb) on platelets (by an assay based on monoclonal antibody-specific immobilization of platelet antigens, MAIPA) and on cultured umbilical vein endothelial cells (by immunoprecipitation experiments) from the same individual. Endothelial cells from a platelet Br(a + b +), and from a platelet Br(a - b +) individual were studied. Our results indicate that endothelial GPIa-IIa is indistinguishable from platelet GPIa-IIa in its ability to express the Bra and Brb alloantigens. The association of Br alloantigens with endothelial GPIa-IIa was confirmed by the results of an assay based on monoclonal antibody-specific immobilization of endothelial antigens (MAIEA). These data further illustrate the structural and immunologic similarity of platelet and endothelial cell GPIa-IIa (VLA-2).
Central Laboratory of the Netherlands Red Cross Blood Transfusion Service, Amsterdam.
J C
JC
Giltay
H J
HJ
Brinkman
A
A
Vlekke
V
V
Kiefel
J A
JA
van Mourik
A E
AE
von dem Borne
D000483:Alleles; D016824:Antigens, Human Platelet; D001792:Blood Platelets / Q000276:immunology*; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000276:immunology*; D006801:Humans; D007231:Infant, Newborn; D039661:Integrin beta3; D007519:Isoantigens / Q000032:analysis*; D010980:Platelet Membrane Glycoproteins / Q000276:immunology*
C055973:5b alloantigen, human; D016824:Antigens, Human Platelet; C061248:ITGB3 protein, human; D039661:Integrin beta3; D007519:Isoantigens; D010980:Platelet Membrane Glycoproteins