Comparison of the pyrogenicity, Limulus activity mitogenicity and complement reactivity of several bacterial endotoxins and related compounds.

The correlation of mitogenicity, complement activation, pyrogenicity and Limulus amebocyte lysate (LAL) gelation induced by 17 bacterial endotoxins (LPS), modified endotoxins, related compounds, and other B cell mitogens was examined. With the use of these compounds, a significant correlation was found between pyrogenicity and mitogenicity (r = 0.85, p is less than 0.0005), pyrogenicity and LAL reactivity (r = 0.84, p is less than 0.0005), and mitogenicity and LAL reactivity (r = 0.72, p is less than 0.0025). In contrast, complement activation by these compounds did not correlate with mitogenicity, pyrogenicity or LAL reactivity (r = 0.09, p is greater than 0.4; r = -0.17, p is greater than 0.3; r = 0.17, p is greater than 0.3, respectively). These results suggest that a specific chemical configuration may induce mitogenicity, pyrogenicity, and LAL reactivity which differs from that responsible for complement activation.