GENETIC-CONTROL OF T-CELL RECEPTOR BJ GENE-EXPRESSION IN PERIPHERAL LYMPHOCYTES OF NORMAL AND RHEUMATOID-ARTHRITIS MONOZYGOTIC TWINS

The amino acids encoded at the junctions of T cell receptor (TCR) V an d J genes directly interact with MHC bound peptides. However, the regu lation of the human TCRBJ gene repertoire has been difficult to analyz e, because of the potentially complex number of BJ gene rearrangements , To overcome this problem, we developed a PCR-ELISA method to study B J gene expression, and compared peripheral T lymphocytes from 12 pairs of monozygotic twins, including 6 rheumatoid arthritis (RA) discordan t pairs, and 5 normals, Analyses of the TCRBV5, 13 and 17 gene familie s, which have been reported to be increased in RA patients, showed: (a ) the three TCRBV transcripts have common features of BJ gene usage; ( b) TCR transcripts from each TCRBV family display a distinctive BJ gen e profile, which is displayed better by CD4(+) than CD8(+) lymphocytes ; (c) the BJ gene repertoires of monozygotic twins are more similar th an those of unrelated individuals; and (6) the inflammation of RA does not induce specific changes in the genetically determined pattern of BJ expression. These results indicate that the frequency of expression particular TCRBV-TCRBJ recombinants in human lymphocytes is controlle d genetically, and is maintained despite the presence of a chronic inf lammatory disease.