Interleukin 1 and tumor necrosis factor: studies on the induction by lipopolysaccharide partial structures

Minimal concentration ranges of lipopolysaccharides, natural and synthetic lipid As, and partial structures were established for the induction of release of IL-1 and TNF from human MNC. LPS was more potent than lipid A. Partial structures of lipid A lacking nonhydroxylated fatty acids were inactive, but in combination with LPS or lipid A exhibited time-dependent synergistic or antagonistic effects.