EVALUATION OF TUMOR-NECROSIS-FACTOR-ALPHA (TNF) AS AN EXPOSURE OR MARKER IN 3 FRENCH COAL-MINING REGIONS

Several studies have shown the crucial role of the tumor necrosis fact or-alpha (TNF) in the fibrosis induced by dusts containing silica and its role in the transition from simple pneumoconiosis (CWSP) to progre ssive massive fibrosis (PMF). To evaluate the nocivity of dust exposur e among coal miners (n = 474) from different mining regions in France (e.g., Nord-Pas de Calais, Lorraine, and Provence), spontaneous and LP S or silica-induced TNF released by peripheral blood monocytes was qua ntified. The primary aim of this effort was to study the link between the prevalence of coal workers pneumoconiosis (CWP) and TNF release. T NF levels were significantly different between active miners from the three regions. However, after correction for age and region, TNF was f ound not to be related to dust exposure. Interestingly, a very low, ho mogeneous expression of TNF was observed in the group from Provence. T hese results are probably related to the absence of pneumoconiosis in this area. A positive relation between profusion and TNF release was f ound for all stimulants among retired miners with PMF. Although in ret ired miners TNF release was consistently higher, the design of the stu dy does not allow this effect to be separated from that of age. Both s ilica and nonstimulated TNF release were found to increase with increa sing radiological symptoms; the opposite was found for LPS-induced rel ease.