title: A molecular basis for the Ia.2 and Ia.19 antigenic determinants.
abstract: The murine Ia antigens, heterodimeric glycoproteins on the surface of immunocompetent cells, restrict immune recognition by their influence on cell-cell interactions. Many serological specificities have been mapped to these molecules, and monoclonal antibodies directed against some of these determinants block antigen presentation to T lymphocytes. As a step toward a better understanding of Ia function, we sought to define the molecular basis of Ia.2 and Ia.19, specificities found on the A alpha chain of only the k or of both k and r haplotypes, respectively. We report nucleotide sequences for the A alpha chain cDNAs of the k, r, and s haplotypes, which, when compared to previously published A alpha sequences, demonstrate the existence of one k-specific amino acid residue and of another present only in the k and r haplotypes. These residues must thus play an important role in the generation of Ia.2 and Ia.19 specificities.
authors.forename: D
authors.initials: D
authors.lastname: Landais
authors.forename: H
authors.initials: H
authors.lastname: Matthes
authors.forename: C
authors.initials: C
authors.lastname: Benoist
authors.forename: D
authors.initials: D
authors.lastname: Mathis
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D000939:Epitopes / Q000235:genetics; D000949:Histocompatibility Antigens Class II / Q000235:genetics*; D051379:Mice; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000939:Epitopes; D000949:Histocompatibility Antigens Class II; D004247:DNA