Infection produces a large array of mediators capable of initiating and maintaining the inflammatory/immune response. Not least among these are the products of the microbes themselves. Unmethylated bacterial deoxyribonucleic acid containing the CpG motif is a potent immunostimulant (7); bacterial heat-shock proteins (HSP) can activate macrophages (8) and also stimulate the production of antibodies. These antibodies frequently cross-react with human HSP and are often invoked as etiologic in autoimmune or autoimmune-like conditions. However, the prototypical inflammatory bacterial product is endotoxin. Endotoxins possess a multitude of biologic effects—most notably, the initiation of a proinflammatory cascade subsequent to binding its specific receptor (CD14) on macrophages. This interaction stimulates the production and release of tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, IL-6, IL-8, IL-12, migration inhibitory factor, chemokines, interferon, eicosanoids and reactive oxygen intermediates (9- 10). These macrophage mediators, in turn, stimulate the production of a second wave of chemokines, cytokines, adhesion molecules and signal molecules in a variety of cell types. Among these are intercellular adhesion molecule, vascular cell adhesion molecule-1, nitric oxide and acute-phase reactants (CRP, serum amyloid A). Thus, endotoxin is one of the most potent biologic response modifiers currently recognized.