T lymphocyte motility toward IL-1 in patients with interstitial lung diseases.

T Lymphocyte alveolitis is considered to be a prerequisite for the formation of epithelioid cell granuloma in sarcoidosis and for the subsequent inflammatory processes in interstitial lung diseases with lung lymphocytosis. To investigate whether T cell accumulation in the lungs is dependent on the recruitment of blood T cells into the lungs, we examined the T cell motility toward IL-1, which has been reported as a T cell chemoattractant, by using a microchemotactic assay. The number of blood T cells migrating toward IL-1 significantly (p less than 0.001) increased when compared with that toward medium. Inferring from the findings that the copresence or pre-incubation of IL-1 with T cells inhibits T cell motility, we confirmed IL-1 as a T cell chemoattractant. In minute amounts of IL-1 (0.000025pg/ml), the number of T cells migrating toward IL-1 significantly increased in sarcoidosis (n = 19) and interstitial lung diseases (ILD) with lung lymphocytosis (n = 5), compared to healthy subjects (n = 17). A raised T cell motility toward IL-1 could be shown in both blood and BALF T cells in sarcoidosis. Conclusively, raised T cell motility toward IL-1 in an in vitro chemotactic assay might contribute to the accumulation of T cells in the lung of patients with sarcoidosis and other ILD.