Allodeterminants and evolution of a novel HLA-B5 CREG antigen, HLA-B SNA.
A novel HLA-B5 CREG gene, HLA-B SNA was cloned and the primary structure was determined. The sequence data showed that HLA-B SNA was identical to HLA-B51 except the alpha 1 domain in which one amino acid substitution at residue 74 and 5 amino acid substitutions associated with the Bw4/Bw6 epitopes were observed between these Ag. The comparison with other HLA-B locus genes suggested that HLA-B SNA evolved from HLA-B51 by gene exchange or recombination at the exon 2 between HLA-B51 and B8. A total of 10 of 14 HLA-B51-specific CTL clones showed significantly weak or no recognition of HLA-B SNA Ag. They also gave the same degree of a lysis of Hmy2CIR cells expressing the HLA-B35/51 chimeric Ag composed of the alpha 1 domain of HLA-B35 and other domains of HLA-B51 as that of Hmy2CIR cells expressing the HLA-B SNA Ag. These results demonstrated that amino acid substitutions within positions 77-83 associated with the HLA-Bw4/Bw6 epitopes have an influence on recognition of the HLA-B SNA antigen by HLA-B51-specific CTL.
Department of Immunology, University of Tokyo, Japan.
M
M
Sekimata
M
M
Hiraiwa
M
M
Andrien
E
E
Dupont
S
S
Karaki
J
J
Yamamoto
K
K
Kano
M
M
Takiguchi
D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D005075:Biological Evolution; D003001:Cloning, Molecular; D003429:Cross Reactions; D000939:Epitopes; D005796:Genes; D015235:HLA-B Antigens / Q000235:genetics*; D006801:Humans; D007111:Immunity, Cellular; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
D000939:Epitopes; D015235:HLA-B Antigens