[Analysis of T cell receptor V beta gene expression in bronchoalveolar lavage fluid lymphocytes from patients with idiopathic interstitial pneumonia].

T lymphocytes in bronchoalveolar lavage (BAL) from idiopathic interstitial pneumonia (IIP) patients are considered to recognize unknown antigens, such as dust, fume, virus or degenerated autoantigens. To analyse the nature of these T lymphocytes, we investigated T cell receptor (TCR) V beta gene usage (22 kinds) in BAL Lymphocytes and Peripheral blood lymphocytes from 10 11P patients and 9 normal controls, using reverse transcriptase-polymerase chain reaction method. In BAL lymphocytes, predominant usage of V beta genes (> 15% of the sum of all V beta transcripts) was recognized in 7 of 10 IIP patients, which appeared to vary in individuals (Case 1: V beta 14, case 2: V beta 3, V beta 5.1, case 5: V beta 2, case 6: V beta 6, case 7: V beta 8, case 8: V beta 7, V beta 20, case 9: V beta 6), whereas no predominant V beta usage was demonstrated in normal controls. It remains to be elucidated whether the BAL lymphocytes expressing predominant V beta genes are involved in the activation of alveolar macrophages, fibroblasts, thereby inducing the production of autoantibodies.