[Immunochemical characterization of platelet-specific alloantigen Baka].
We investigated the location of platelet-specific alloantigen Baka on platelet membrane glycoproteins. In indirect immunoprecipitation experiments, the anti-Baka antibody precipitated glycoprotein (GP) II b and a small amount of GP III a. The immunoblots using partially purified GP II b/III a complex as the target antigen indicated that GP II b alpha carried the Baka alloantigen. When the partially purified GP II b/III a complex digested with chymotrypsin was examined, the Baka alloantigen was found on a 65 kD fragment derived from GP II b alpha under reducing conditions. In addition, the immunoblots after two-dimensional nonreduced-reduced SDS-PAGE directly indicated that the 65 kD fragment had a mol. wt. of 80 kD under nonreducing conditions. The immunoblots using platelets digested in situ with chymotrypsin indicated that the 65 kD fragment of GP II b alpha was retained by the platelet membrane. We conclude, therefore, that the Baka alloantigen is located on a 65 kD fragment that represents the membrane side of the cleavage site of chymotrypsin on GP II b alpha.
Tomiyama
Y
Y
Kurata
Y
Y
Shibata
Y
Y
Take
H
H
Furubayashi
T
T
Tsubakio
T
T
Yonezawa
T
T
Tarui
S
S
D016824:Antigens, Human Platelet; D001792:Blood Platelets / Q000276:immunology*; D002918:Chymotrypsin; D006801:Humans; D015151:Immunoblotting; D007519:Isoantigens / Q000276:immunology*; D010980:Platelet Membrane Glycoproteins / Q000276:immunology / Q000378:metabolism; D011233:Precipitin Tests
C044561:3a alloantigen, human; D016824:Antigens, Human Platelet; D007519:Isoantigens; D010980:Platelet Membrane Glycoproteins; D002918:Chymotrypsin