Cell surface expression of the amino-terminal domain of A kappa alpha. Recognition of an isolated MHC antigenic structure by allospecific T cells but not alloantibodies.
To evaluate the relationship between structure and function of the alpha 1 and beta 1 domains of class II MHC molecules, a strategy has been developed whereby isolated alpha 1 or beta 1 domains can be expressed on the surface of transfected mouse L cells as a part of a hybrid class II/class I molecule. The construction and expression of a chimeric class II/class I gene encoding the first two exons of A kappa alpha linked to the C2, TM and cytoplasmic exons of H-2Dd (A kappa alpha 1/DdC2) are described. High levels of A kappa alpha 1/DdC2 protein were detected on transfected L cells with a DdC2-specific mAb. An anti-Ia xenoantiserum specifically bound to A kappa alpha 1/DdC2-transfected L cells, although 12 different mAb reactive against I-A kappa alpha and an anti-Ia kappa alloantiserum did not bind these cells. However, alloreactive Ia kappa-specific CTL lines were able specifically to lyse cells expressing the hybrid A kappa alpha 1/DdC2 molecule. This indicates that the isolated A kappa alpha 1 domain preserves some of the structure of the native molecule and demonstrates the recognition by T cells of domain-specific A alpha allodeterminants.
D000818:Animals; D000939:Epitopes / Q000235:genetics / Q000276:immunology; D005813:Genes, Synthetic; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D007518:Isoantibodies / Q000276:immunology*; D007739:L Cells; D051379:Mice; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000235:genetics; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014162:Transfection
D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D007518:Isoantibodies; D011993:Recombinant Fusion Proteins