Characterization of new murine monoclonal antibodies directed against glycophorins C and D.
Six new murine monoclonal antibodies (mAbs) directed to the erythrocyte membrane glycophorins C (GPC) and D (GPD) were obtained from splenocytes of different BALB/c mice immunized with human red blood cells, and fully characterized. The mAbs were selected by agglutination tests with control and Gerbich-negative cells, and by immunoblotting analysis. They showed specificity for the N-terminal domain(s) of GPC (and GPD) and were classified into three categories by competitive analysis using 125I-labelled antibodies and real-time biospecific interaction. The first group (NaM10-7G11, NaM70-1G4 and NaM77-7B6) compete for epitope(s) located at the N-terminal portion of GPC. Agglutination-inhibition tests revealed that the 7G11 epitope involves the amino group of Met1 and sialic acid residue(s) whereas the 1G4 and 7B6 epitopes contain O-glycans. NaM89-2G11 belongs to a second group; its epitope is located in a region including Glu17, Asp19 and (an) O-glycan(s). The third group comprises mAbs NaM19-3C4 and NaM98-3C1 which bind to both GPC and GPD in proximity of the binding site of human anti-Ge:3 antibodies. In addition, mAb 3C4 (anti-GPC/GPD) was found to bind to approximately 125,000 sites per red cell. Considering that the ratio of the GPC to GPD is about 3-4 to 1, the number of GPC and GPD molecules was estimated as 95,000 and 35,000, respectively.
Loirat
M J
MJ
Centre Régional de Transfusion Sanguine, Nantes, France.
Dahr
W
W
Muller
J Y
JY
Blanchard
D
D
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000918:Antibody Specificity; D001667:Binding, Competitive; D018604:Epitope Mapping; D004912:Erythrocytes / Q000276:immunology; D006021:Glycophorins / Q000276:immunology*; D006386:Hemagglutination Tests; D006801:Humans; D015151:Immunoblotting; D007457:Iodine Radioisotopes; D051379:Mice; D008807:Mice, Inbred BALB C
D000911:Antibodies, Monoclonal; D006021:Glycophorins; D007457:Iodine Radioisotopes