 - Immunomodulators e.g., interleukins, interferons, cyclosporine, HIV vaccine, systemic cytotoxic chemotherapy, or investigational therapy within 30 days prior to study entry. Individuals receiving either stable physiologic glucocorticoid doses, corticosteroids for acute therapy for pneumocystis pneumonia, or a short course 2 weeks or less of pharmacologic glucocorticoid therapy will not be excluded. 