Fine specificity of the alloantiserum MSD-51: epitope mapping of HLA-DRw53 determinants.
HLA-DRw53 is a supertypic specificity expressed by HLA-DR4-, HLA-DR7-, and HLA-DR9-positive cells. In the present study, the fine specificity of an HLA-DRw53-specific alloantiserum (MSD-51) was analyzed in serology and by the isoelectric focusing technique. In serology, MSD-51 recognized HLA-DRw53-positive cells with the exception of cells expressing the HLA-DR7/DRw53/DQw9 haplotype. The immunoprecipitation studies and the use of the IgM-reducing agent dithiothreitol revealed that MSD-51 consisted of at least two antibodies: (1) an IgM antibody which reacted with the HLA-DRB4 gene product of HLA-DRw53-positive cells, except HLA-DR7/DRw53/DQw9-expressing cells, and (2) at least one IgG antibody which recognized a linear sequence or conformational structure formed by positions 67 to 70 on the HLA-DRB1 gene product of HLA-DR4- and HLA-DR9-positive cells. These findings demonstrate the complexity of the supertypic HLA-DRw53 antigen analyzed with a serologically well-defined HLA-DRw53-specific alloantiserum.
Lardy
N M
NM
Department of Transplantation Immunology, The Netherlands Red Cross Blood Transfusion Service, Amsterdam.
van der Horst
A R
AR
van den Berg-Loonen
E M
EM
Bontrop
R E
RE
de Waal
L P
LP
D000595:Amino Acid Sequence; D000918:Antibody Specificity; D000939:Epitopes / Q000276:immunology*; D006684:HLA-DR Antigens / Q000235:genetics / Q000276:immunology*; D059811:HLA-DRB1 Chains; D059845:HLA-DRB4 Chains; D000949:Histocompatibility Antigens Class II / Q000235:genetics; D006801:Humans; D007136:Immunoglobulins / Q000276:immunology; D007518:Isoantibodies / Q000276:immunology*; D007525:Isoelectric Focusing; D008969:Molecular Sequence Data; D012689:Sequence Homology, Nucleic Acid; D014407:Tumor Cells, Cultured
D000939:Epitopes; D006684:HLA-DR Antigens; C050610:HLA-DR53; D059811:HLA-DRB1 Chains; D059845:HLA-DRB4 Chains; D000949:Histocompatibility Antigens Class II; D007136:Immunoglobulins; D007518:Isoantibodies