T cell receptor-Vβ repertoires in lung and blood CD4+ and CD8+ T cells of pulmonary sarcoidosis patients.

Background: Sarcoidosis patients have accumulations of activated CD4+ T cells in affected organs, such as the lungs. T cell receptor (TCR) Vβ-chain usage has been incompletely characterized in these patients.

Methods: We surveyed the TCR Vβ usage in CD4+ and CD8+ T cells in bronchoalveolar lavage (BAL) cells and peripheral blood mononuclear cells (PBMC) from 15 HLA-typed Scandinavian sarcoidosis patients. In addition, PBMC from 9 healthy volunteers and BAL cells from three of them were examined. Using 21 Vβ family-specific antibodies, we covered approximately 70% of all Vβ chains.

Results: In BAL T cells from sarcoidosis patients, we identified 16 CD4+ T cell expansions in 271 analyses (5.9%) and 21 CD8+ expansions in 240 analyses (8.7%). In PBMC we found 9 CD4+ expansions in 276 analyses (3.3%) and 12 CD8+ expansions out of 263 analyses (4.6%). Consistent with previous studies we found Vβ8 and Vβ16 expansions in sarcoidosis patients' lungs. In addition, we found lung restricted Vβ22 expansions in three HLA DRB1 03+ patients. However, we found no statistically significant difference in frequency of expansions between patients and healthy controls.

Conclusions: The identified T cell expansions in present study indicate specific antigen recognition in the lungs of sarcoidosis patients.