Abstract
Oxidant production by peripheral granulocytes stimulated with phorbol myristate acetate (PMA) was investigated in 11 patients with idiopathic pulmonary fibrosis (IPF), 6 with interstitial pneumonia associated with collagen vascular disease (IP-CVD), 8 with sarcoidosis and 12 healthy subjects. Oxidant production was examined by flow cytometry using dichlorofluorescein deacetate. The reactivity of granulocytes to PMA was assessed according to the ratio between mean fluorescent intensity of granulocytes stimulated maximally with PMA and that without PMA, (stimulation index: S. I.). The concentration of PMA that induced half maximal fluorescent intensity of granulocytes (PC1/2max) was used as the index of sensitivity.
The S. I. was 7.2±0.45 in IPF, 6.3±0.6in IP-CVD, 6.0±0.71 in sarcoidosis, and 5.8±0.2 in healthy subjects. However differences between groups were not significant. PC1/2max was 7.3±2.1ng/ml in IPF, 9.1±3.0ng/ml in IP-CVD, 12±6.9ng/ml in sarcoidosis and 16.1±5.8ng/ml in healthy subjects. There was significant difference between IPF and healthy subjects (p<0.05) indicating that peripheral granulocytes in patients with IPF are more highly sensitive to PMA than healthy subjects.
