Reduced Expression of the Survivin Gene in PBMC from Silicosis Patients
To explore the mechanism involved in immunological disorders associated with silicosis, the expression of IAP family genes in peripheral blood mononuclear cells from silicosis patients was examined. Relative gene expression was assayed using the multiplex RT-PCR for the XIAP and survivin genes. The correlation between those expression levels and various clinical parameters was then analyzed. The relative expression level of the survivin gene was reduced in silicosis patients as compared with that of healthy volunteers. The expression level of survivin positively correlated with PC02 values. These results support the existence of two populations of T lymphocytes in silicosis patients, one resistant to Fas-mediated apoptosis (a self-recognizing long-surviving fraction) and the other one sensitive to silica-induced apoptosis and repeatedly undergoing death and recruitment.