Die Inaktivierung der endotoxischen Wirksamkeit bakterieller Lipopolysaccharide in Serum, Plasma und Vollblut vom Pferd

Abstract

The action of horse serum or plasma on the highly purified lipopolysaccharides of Salmonella abortus equi and S. paratyphi B at 37[degree], but not at 4[degree]C, during 12 to 24 hours, causes complete inactivation of their endotoxic character, The serum factor that neutralizes the endotoxin can be demonstrated by following the loss of the pyrogenic and leucopenic effect of the bacterial lipopolysaccharides incubated with serum or plasma after reinjection of the mixture into the horse. An inactivation of a dose of 20 [mu]g lipo-polysaccharide, which is strongly pyrogenic for a horse, is evident even after incubation with 1 ml of horse serum at 37[degree]C. A decrease of the pyrogenic effect to one half (average temperature maximum before incubation 1.7[degree]C, after 3 hours incubation 0.9[degree]C) occurs within 3-12 hours on incubation of 5-20 [mu]g lipopolysaccharide in 1 liter of fresh horse whole blood. Incubation with whole blood results in a significant lengthening of the latent period between injection and temperature rise of 56 minutes, on the average, in contrast to known observations on dogs and humans (with a shortening of the latent period), with untreated lipopolysaccharides an average latent period of 102 minutes. From these experiments nothing definite can as yet be said concerning the nature of the pyrogenic principle (whether an exogenous residual pyrogen or a so-called endogenous pyrogen).