[The variation of T-cell clonal repertoire in patients with systemic lupus erythematosus (SLE) following autologous peripheral blood hematopoietic stem cell transplantation].

OBJECTIVE: Analyze the variation of T cell receptor(beta) (TCRbeta) CDR3 gene expressing repertoire in systemic lupus erythematosus (SLE) patients before and after autologous peripheral blood hematopoietic stem cell transplantation (APBSCT), to search the pathogenesis of SLE and characteristics of T cell reconstitute immune after APBSCT.

METHODS: Reverse transcriptase - polymerase chain reaction (RT-PCR) amplified 25 subfamily genes of TCRbeta prom peripheral blood lymphocytes (PBLs) of SLE patient with APBSCT and run denaturation polyacrylamide sequencing gel electrophoresis, set up a map of TCRbetaCDR3 gene expressing repertoire. The bands of TCRbeta gene repertoire in the electrophoresis gel can be used to analyze the variety of T cell clones which expanded and disappeared in cases of SLE. Cut the bands and sequencing. Compare sequences of TCRbetagenes in normal and abnormal T cell clones to understand the relationship between TCRbeta gene and autoimmune diseases.

RESULTS: In the normal control group, TCRbeta gene repertoires show more than 10 bands in each of 25 TCRbetaV families, characterized as Gaussian distribution. TCRbeta gene repertoire in the 8 patients with SLE were abnormally. Four patients expressed TCRbetaV13.1 gene preferentially. Three patients had TCRbetaV8, TCRbetaV9 and TCRbetaV18 genes over expressed. These over expressive genes represented the oligoclonal expansion of T cell populations. After APBSCT the TCRbeta gene repertoires regained CDR3 polymorphism in 5 patients, some of them recovered to normal completely. The sequencing analyse show dense and strong band in map of TCRbeta gene repertoires were T cell monoclonal or oligoclonal expansion frequently. In a case of SLE an amino acid sequence of TCRbetaV8 CDR3 was same to a sequence of disease correlative T cell clone with ankylosing spondylitis that had been reported in a literature before.

CONCLUSION: SLE patients have oligoclonal expansion of T cell that related with the pathogenesis of autoimmune disease. After APBSCT, T cell clones recover to normal distribution. T cell clones that related with disease have been suppressed during immunological reconstitution. It may be a main reason the SLE get remission after transplantation.