UP-REGULATION OF ANTIGENS ON ALVEOLAR MACROPHAGES IN QUARTZ EXPOSED RATS

We have analysed the expression of the OX-6 and OX-42 antigens on alve olar macrophages in rats after intratracheal exposure to quartz. Eight female Sprague Dawley rats were included in the study. Four were expo sed to physiological saline and four to quartz dust. The rats were sac rificed after 58 +/- 2 weeks and alveolar macrophages were harvested a nd analysed by flow cytometry. We found a significant higher amount of both antigens on alveolar macrophages harvested from quartz exposed r ats. However, we did not find any significant difference in the percen tage positive labeled cells between the two groups. We conclude that q uartz dust induces up-regulation of functional receptors on alveolar m acrophages in mts and that quantitative analysis of these receptors ma y serve as inflammatory markers in the bronchoalveolar space.