HLA-C expression on platelets: studies with an HLA-Cw1-specific human monoclonal antibody.
OBJECTIVE
The expression of HLA-C on the surface of platelets is rarely studied due to the lack of proper alloantisera. We addressed this question using an IgM human monoclonal antibody directed against HLA-Cw1 (VP6G3).


METHODS
Both flow cytometry and complement dependent cytotoxicity studies were used in the current analysis.


RESULTS
The expression of the HLA-Cw1 antigen on platelets is lower than on peripheral blood lymphocytes as shown by flow cytometry. Variation in expression levels between individuals is also observed. Using this antibody in a complement-dependent cytotoxicity assay, we did not observe lysis using platelets as targets, whereas peripheral blood lymphocytes of the same blood donors were adequately lysed.


CONCLUSIONS
These results confirm that platelets indeed express HLA-C. Furthermore, the results support the insignificant role of HLA-C in immunological platelet refractoriness.
Datema
G
G
Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands.
Stein
S
S
Eijsink
C
C
Mulder
A
A
Claas
F H
FH
Doxiadis
I I
II
D000911:Antibodies, Monoclonal / Q000378:metabolism; D000918:Antibody Specificity; D001792:Blood Platelets / Q000737:chemistry / Q000276:immunology*; D003601:Cytotoxicity Tests, Immunologic; D005434:Flow Cytometry; D015789:HLA-A2 Antigen / Q000378:metabolism; D015236:HLA-C Antigens / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007075:Immunoglobulin M / Q000378:metabolism; D008214:Lymphocytes / Q000276:immunology
D000911:Antibodies, Monoclonal; D015789:HLA-A2 Antigen; D015236:HLA-C Antigens; C047431:HLA-Cw1 antigen; D007075:Immunoglobulin M