Thromb Haemost 1991; 66(04): 494-499
DOI: 10.1055/s-0038-1646445
Review Article
Schattauer GmbH Stuttgart

A Monoclonal Antibody, VM64, Reacts with a 130 kDa Glycoprotein Common to Platelets and Endothelial Cells: Heterogeneity in Antibody Binding to Human Aortic Endothelial Cells

Alexey V Mazurov
The Institute of Experimental Cardiology, Cardiology Research Center, Moscow, USSR
,
Dimitry V Vinogradov
The Institute of Experimental Cardiology, Cardiology Research Center, Moscow, USSR
,
Naile V Kabaeva
The Institute of Experimental Cardiology, Cardiology Research Center, Moscow, USSR
,
Galina N Antonova
The Institute of Experimental Cardiology, Cardiology Research Center, Moscow, USSR
,
Yuri A Romanov
The Institute of Experimental Cardiology, Cardiology Research Center, Moscow, USSR
,
Tatjana N VIasik
The Institute of Experimental Cardiology, Cardiology Research Center, Moscow, USSR
,
Alexander S Antonov
The Institute of Experimental Cardiology, Cardiology Research Center, Moscow, USSR
,
Vladimir N Smirnov
The Institute of Experimental Cardiology, Cardiology Research Center, Moscow, USSR
› Author Affiliations
Further Information

Publication History

Received 08 November 1990

Accepted 04 April 1991

Publication Date:
25 July 2018 (online)

Summary

A new monoclonal antibody (mAb), VM64, reacts with a common antigen on the surface of human platelets and vascular endothelial cells (EC). Under nonreduced conditions it recognized in immunoblotting a protein of 130 kDa both in platelets and EC. VM64 precipitated the same 130 kDa protein from the lysate of surface radioiodinated platelets. Electrophoretic mobility of this protein was not altered by reduction and differed from the bands precipitated by reference mAb against platelet glycoproteins (GP) Ia–IIa, Ib, IIb–IIIa and GMP130. VM64 binding to platelets and EC was specific and saturable. The number of binding sites on platelets was 9.9 ± 3.5 × 103 per platelet and on the surface of EC monolayer – 2.40 ± 0.32 × 106 per cell. VM64 also binds to platelets from Glanzmann's thrombasthenia patients which lack GPIIb–IIIa. VM64 did not affect platelet aggregation induced by ADP, collagen, thrombin and ristocetin. In the monolayers of EC from umbilical vein and human aorta, VM64 stained the area at the periphery of the cells adjacent to the cell-cell boundaries. In preconfluent cultures preferential staining was observed at the active leading margins of the cells. Unlike EC cultures from umbilical vein, where all cells were positively stained, in aortic EC cultures some unstained or poorly stained cells were constantly present, indicating a heterogeneity of EC population related to the expression of VM64 antigen. The biochemical characteristics of VM64 antigen, its presence both on platelets and EC and typical distribution on the surface of EC suggested that this antigen is identical to PECAM (CD31) protein.