Analyses for the ?/? T Cell Receptor Gene Rearrangement and CDR3 Repertoire in Active Pulmonary Tuberculosis Patients / 中国免疫学杂志

ABSTRACT

Objective:To establish a method of multi-PCR to amplify the complete DNA sequence (CDS) of TCR ? and ? chain of the antigen-specific T lymphocytes in local pathologic specimen of active pulmonary tuberculosis patients, and to analyze ?/? T cell receptor gene rearrangement and CDR3 repertoire.Methods:The lymphocytes in bronchoalveolar lavage (BAL) of active pulmonary tuberculosis patients were separated. Following total RNA extraction, cDNA synthesis, Multi-PCR, recombinant clones construction, and sequencing, the CDS of TCR ? and ? chains from these lymphocytes were analyzed by using software of DNAstar and internet TCR resources.Results:24 of ? chain CDS and 13 of ? chain CDS from 3 samples of BAL were obtained. As for TCR ? chain, AV1S2 (54%), AV12S3 (41%), and AV12S2(5%) appeared frequently. BV2(38%), BV29S1(46%), BV14(3%), and BV4S2(3%) in TCR ? chain appeared more often. There were CDR3 diversities between samples and even in the same sample by amino acid sequence analysis, but there were a few identical or similar amino acid sequences. There was the same amino acid sequence of SVGTGTLHQETQY in CDR3 region of ? chain of BAL sample No.1 and No.2; The sequence of AVRDWAGNMLT appeared in two ? chains of BAL sample No.2 and No.3; Moreover, the sequence of AV…DNN…RLM appeared in ? chains of BAL sample No.2 and No.3.Conclusion:A method of Multi-PCR is used to amplify TCR ? and ? chain CDS of tuberculosis patients. There are characteristic T cell clones to proliferate,with TCR ? and ? chain repertiore skewing in local infective focus. The sequences of CDR3 in different TCR clones are mostly different but there are a few identical or similar sequences in the same patient or even between different patients. The identical amino acid sequences of CDR3 are possibly specific for recognizing MTB polypeptide.