Polymorphic DQ alpha and DQ beta interactions dictate HLA class II determinants of allo-recognition.
Year: 1990
Type: article
Abstract: 18 transfected cell lines were generated that expressed distinct DQ molecules related to the serologically defined HLA-DQw3 specificity. These transfectants were constructed using site-directed mutagenesis to introduce nucleotide substitutions into DQ3.2 beta cDNA, followed by retrovirus-mediated gene expression of the mutagenized genes in human B cell lines with different endogenous DQ alpha chains. The capacity of particular class II dimers to stimulate alloreactive T cell clones was investigated. T cell activation was found to be dependent on both DQ alpha and DQ beta chains. In some cases, single amino acid substitutions at codons 13, 26, 45, or 57 of the DQ beta chain were sufficient to dramatically alter T cell reactivity; T cell recognition of these substitutions, however, was strongly influenced by the alpha chain polymorphisms present in the stimulatory class II dimer. Both gain and loss of major serologic and cellular specificities associated with specific DQw3+ alleles were observed with a limited array of site-directed substitutions.
DOI: 10.1084/jem.171.1.85
Authors: W W Kwok, E Mickelson, S Masewicz, E C Milner, J Hansen, G T Nepom
Language: English
Topic: T-cell and B-cell Immunology
Subfield: Immunology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W1994543049