(en‵dō-tok'sĭn )

[ endo- + toxin ]

A lipopolysaccharide that is part of the cell wall of gram-negative bacteria. It binds with CD14 receptors on leukocytes. The linkage stimulates the release of interleukin-1, tumor necrosis factor, and other cytokines, which affect inflammation, the specific immune response, vascular tone, hematopoiesis, and wound healing. When large amounts of lipopolysaccharides are present, sepsis or systemic inflammatory response syndrome occurs. Endotoxins are still active even after bacteria are destroyed; thus, in treating some infections, the positive effects of antibiotics may be delayed.

SEE: bacterium; inflammation; exotoxin; sepsis; systemic inflammatory response syndrome.