A new polymorphic determinant on HLA-DQ molecules.
In man, the immune response genes are located within the HLA-D/DR region, and the gene products, the Ia antigens, are expressed on B lymphocytes, monocytes, and a percentage of null cells and activated T lymphocytes. We recently identified a human Ia antigen, K19, which appeared to be limited in its expression to B lymphocytes, and to be preferentially expressed on the more mature cells within this population. This work was facilitated by a monoclonal antibody. HK-19, which recognized a monomorphic determinant of this Ia molecule. We now report the characterization of a second monoclonal antibody, HK-13, which recognized the same molecule as HK-19, but only on cells from some individuals. The greater affinity of HK-13 allowed more complete characterization of the K19/K13 molecule. This characterization included cytofluorography, two-dimensional gel electrophoresis, tryptic peptide mapping, and partial N-terminal amino acid sequencing, and indicated that K19 and K13 were epitopes on HLA-DQ (DC) molecules. The pattern of reactivity of HK-13 on a panel of typing cells did not correlate with any of the known HLA-DQ polymorphic determinants. Thus, HK-13 is a new polymorphic determinant of the HLA-DQ series.
M A
MA
Shipp
P
P
Ahmed
C C
CC
Kannapell
J C
JC
Ford
D
D
McCourt
J F
JF
Leykam
M
M
Zacheis
C
C
Bono
J M
JM
Davie
E
E
Mustain
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology; D000942:Antigens, Bacterial; D000954:Antigens, Surface / Q000032:analysis*; D002460:Cell Line; D000939:Epitopes / Q000032:analysis*; D005452:Fluoresceins; D006683:HLA-DQ Antigens; D000949:Histocompatibility Antigens Class II / Q000032:analysis / Q000276:immunology*; D006801:Humans; D011110:Polymorphism, Genetic
D000911:Antibodies, Monoclonal; D000942:Antigens, Bacterial; D000954:Antigens, Surface; D000939:Epitopes; D005452:Fluoresceins; D006683:HLA-DQ Antigens; D000949:Histocompatibility Antigens Class II; C030659:K antigens