The platelet proteins of 9 thrombasthenic patients from 7 families were analysed by
high resolution two-dimensional gel electrophoresis (HR-2DE) and crossed immunoelectrophoresis
(CIE). In 7 patients both glycoproteins (GPs) IIb and Ilia were absent or reduced
to roughly the same extent. In two related patients only a trace of GP Ilb-IIIa complex
was detected in CIE, but HR-2DE revealed a glycopeptide in the position of GP Ilia
in an amount comparable to type II thrombasthenia. This GP Ilia-like component was
neither recognized normally by anti-GP Ilb-IIIa antibodies nor labeled by surface
iodination. In unreduced-reduced two-dimensional gel electrophoresis two components
were observed in the region of GP Ilia. The assumption of a structural variant of
GP Ilia in the two related patients is discussed.
Keywords
Thrombasthenia - Platelet membrane glycoproteins - Glycoprotein IIb-IIIa complex