Vβ T cell receptor (TCR) genes in circulating cells of patients with systemic lupus erythematosus and their healthy relatives

ObjectiveWe investigated the proportion of Vβ T cell receptor (TCR) gene expression in peripheral CD3+ lymphocytes in familial and non-familial systemic lupus erythematosus (SLE) patients.MethodThe Vβ TCR repertoire was studied in 14 families in which several members had SLE. The Vβ TCR usage in SLE patients (n = 27) was compared with that in healthy members of these multiplex families (n = 47), in 37 sporadic SLE patients who had no relatives with SLE, and in 15 healthy unrelated controls. Vβ TCR repertoire expression was studied by multiparameter flow cytometry with the use of an array of 24 different Vβ TCR gene family-specific monoclonal antibodies.ResultsWe found the same Vβ TCR expression profile in the comparisons between sporadic SLE and familial SLE cases and healthy relatives, which included increased expression of Vβ 5.2, Vβ 11 and Vβ 16, and lower expression of Vβ 3, Vβ 4, Vβ 7.1 and Vβ 17. Interestingly, solely Vβ 17 was differentially expressed among sporadic and familial SLE. Also, increased expression of Vβ 9 was the hallmark among familial SLE (casesand h ealthy relatives) in comparison to controls.ConclusionThese results highlight the notion that the final profile of the Vβ TCR repertoire seen in familial and non-familial SLE seems to arise from the interaction of genetic, environmental, and immunoregulatory factors. Furthermore, it may contribute to the immunologic abnormalities affecting relatives of SLE patients.