Asbestos inhalation and the induction of splenic lymphocytic proliferation in the rat.

T here is evidence that the alveolar macrophage plays a critical role in the pathogenesis of asbestosis, since this phagocytic cell is an important component of evolving lesions in this disease.1 We have recently demonstrated that alveolar macrophages obtained from asbestos-exposed rats can evoke a stabilized physical interaction during in vitro culture with autologous T cell-enriched splenic lymphocytes.2 This interaction was shown to have two components: an effect analogous to that produced by subjecting macrophages to the peroxidant action of sodium metaperiodate (Na104)3 and an effect which was similar to antigendirected clustering of lymphocytes around macrophages.4 As an extension of the previous study we now report that alveolar macrophages obtained from asbestos-exposed rats can initiate a vigorous in vitro splemc lymphocyte proliferative response.