 Specific Aim 2: To determine the effect of infliximab on intermediate markers of biological function in CBD. In vitro studies will examine the effect of infliximab on blood and lung cells in culture, as measured by a decrease in beryllium Be-stimulated lymphocyte proliferation; a decrease in Be-stimulated cytokine production, including TNF-a, IFN-g, and IL-2; altered Be-stimulated apoptosis of macrophages or lymphocytes. 