Soluble interleukin-2 receptor levels in serum may correlate with disease activity in sarcoidosis. T cells that accumulate within pulmonary sarcoid lesions may demonstrate downregulation of their T-cell receptor-CD3 complex. Tumor necrosis factor-α, interleukin-1 β, and interleukin-6 appear to be increased in sarcoidosis and interact with various cell types to propagate the disease process. B cells appear to play a greater role in sarcoid pathogenesis than was earlier thought, as evidenced by enhanced products of humoral immune response (ie, immunoglobulins and immune complexes). Clinically, sarcoidosis may initially present with a variety of cutaneous manifestations. Both magnetic resonance imaging and ultrasonography may be useful in evaluating the presence of abdominal sarcoidosis. J001 scintigraphy may provide a new diagnostic technique in assessing pulmonary and lymph-node involvement in sarcoid.