The HLA-A,B,C genotype of the class I negative cell line Daudi reveals novel HLA-A and -B alleles.
Daudi, a lymphoblastoid B cell line derived from an African Burkitt lymphoma does not express HLA-A,B,C antigens at the cell surface. Although HLA-A,B,C heavy chains are made normally they do not assemble into functional molecules because beta 2-microglobulin is absent. Previous serological analysis of somatic cell hybrids indicated that the HLA haplotypes of Daudi encoded HLA-A1, A10(A26), B17, and B16(38) antigens. Here we describe the application of molecular methods: ARMS-PCR, cDNA cloning and sequencing, immunoprecipitation and gel electrophoresis, to define the class I genotype of the Daudi cell line which is HLA-A*0102, A*6601, B*5801, B*5802, Cw*0302 and Cw*0602. With the exception of the B38 antigen, which is not a product of the alleles defined, the genotype is consistent with the serological description. Two previously undiscovered alleles emerged from this analysis: A*0102 and B*5802. The A*0102 allele differs from A*0101 by 5 nucleotide substitutions within exon 2 where it has a motif shared with A*30 alleles; the B*5802 allele differs from B*5801 by 3 substitutions in exon 3 where it has a motif shared with B*14 alleles. Subtyping HLA-A1 alleles showed A*0102 was well represented amongst individuals typed serologically as A1 in an African population but was absent from caucasoids. B*5802 has been found in a second individual. Thus the novel A and B alleles are not specific to the Daudi tumor. Overall, this analysis of a single East African cell illustrates the power of molecular methods to define new class I HLA alleles in non-caucasoid populations.
Browning
M J
MJ
Cancer Immunology Laboratory, ICRF, John Radcliffe Hospital, Oxford, United Kingdom.
Madrigal
J A
JA
Krausa
P
P
Kowalski
H
H
Allsopp
C E
CE
Little
A M
AM
Turner
S
S
Adams
E J
EJ
Arnett
K L
KL
Bodmer
W F
WF
D000351:Africa, Eastern; D000483:Alleles; D001483:Base Sequence; D044383:Black People / Q000235:genetics; D004247:DNA / Q000097:blood; D005787:Gene Frequency; D005805:Genes, MHC Class I / Q000235:genetics*; D015234:HLA-A Antigens / Q000145:classification / Q000235:genetics*; D015235:HLA-B Antigens / Q000145:classification / Q000235:genetics*; D015236:HLA-C Antigens / Q000145:classification / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D014407:Tumor Cells, Cultured / Q000276:immunology*
D015234:HLA-A Antigens; D015235:HLA-B Antigens; D015236:HLA-C Antigens; D004247:DNA