Non-restricted T cell receptor (TCR)-V alpha and -V beta gene usage in patients with pulmonary sarcoidosis

Sarcoidosis is a systemic granulomatous disease of unknown etiology characterized by the pronounced accumulation of CD4+ T cells and macrophages in the affected organs. TCR variable (V) alpha and V beta gene usage in patients with sarcoidosis is still a matter of discussion. In this investigation, we analysed TCR-V alpha and -V beta gene usage in bronchoalveolar lavage fluid (BALF) and peripheral blood mononuclear cells (PBMC) of 30 patients with active pulmonary sarcoidosis using an adapter ligation method, reverse transcriptase-polymerase chain reaction (RT-PCR), and sequence-specific oligonucleotide probe (SSOP) analyses. There was no significant difference in TCR-V alpha or -V beta gene usage between BALF (n = 12) or PBMC (n = 27) of patients and PBMC of healthy subjects (n = 10). Neither selective TCR-V alpha nor -V beta expansion was observed in the paired BALF and PBMC from seven of nine patients. However, selective expansions were observed in a few TCR-V alpha or -V beta subsets in the BALF or PBMC of some individuals. Although a modest increase in a few TCR-V alpha or -V beta subsets was observed in the BALF or PBMC of some individuals, the increased TCR-V alpha or -V beta subsets were not closely associated with the HLA-DRB1, DQA1, DQB1, and DPB1 alleles of these patients. These results suggest that TCR-V alpha or -V beta gene usage is not restricted in both lung and peripheral blood in the majority of patients with active pulmonary sarcoidosis.