title: Study of aspartate at residue 9 of HLA-C molecules in Japanese patients with psoriasis vulgaris.
abstract: The frequency of aspartate at residue 9 (Asp-9) of HLA-C molecules was investigated among 75 Japanese patients with psoriasis vulgaris and 50 healthy controls. We developed a technique of polymerase chain reaction sequence-specific primer (PCR-SSP) amplification of genomic DNA for HLA-C alleles with a codon for Asp-9. The specificity of amplification was confirmed by direct sequencing of the amplified products and amplification from total RNA (RT-PCR). Asp-9 was positive in all individuals with Cw6 and/or Cw7, but negative in the others, indicating that Asp-9 was specific to Cw6 and Cw7 antigens in our subjects. The frequency of Asp-9 was significantly increased in the patient group (48% vs. 20%; P < 0.002). The frequency of alanine at residue 73 (Ala-73), which was positive for Cw4, Cw6, Cw7, and some C blanks, was also increased in our previous study (81% vs. 48%; P < 0.0001). Asp-9 is located on a beta sheet of alpha 1 domain of HLA-C molecule and influences the peptide binding of the C pocket of the groove together with Ala-73. Both Asp-9 and Ala-73 could contribute to the disease susceptibility to psoriasis vulgaris in the immune responses.
authors.affiliation: Department of Dermatology, University of Tokyo School of Medicine, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Asahina
authors.forename: S
authors.initials: S
authors.lastname: Kuwata
authors.forename: K
authors.initials: K
authors.lastname: Tokunaga
authors.forename: T
authors.initials: T
authors.lastname: Juji
authors.forename: H
authors.initials: H
authors.lastname: Nakagawa
mesh_terms: D000483:Alleles; D001224:Aspartic Acid / Q000737:chemistry / Q000235:genetics; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D016022:Case-Control Studies; D003062:Codon / Q000235:genetics; D016384:Consensus Sequence; D004247:DNA / Q000235:genetics; D017931:DNA Primers / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D015236:HLA-C Antigens / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D007564:Japan; D008297:Male; D008969:Molecular Sequence Data; D015394:Molecular Structure; D016133:Polymerase Chain Reaction; D011565:Psoriasis / Q000235:genetics* / Q000276:immunology*
chemical_list: D003062:Codon; D017931:DNA Primers; D015236:HLA-C Antigens; C528994:HLA-C*06 antigen; C040178:HLA-C*70 antigen; D001224:Aspartic Acid; D004247:DNA