Correlation between endotoxin‐neutralizing capacity of human plasma as tested by the limulus‐amebocyte‐lysate‐test and plasma protein levels

摘要

>In the present study the endotoxin-neutralizing capacity of human plasma obtained from healthy volunteers was determined by use of the limulus-amebocyte-lysate test. The extent of the endotoxin-neutralizing capacity which showed a very broad variation was correlated to the plasma levels of some proteins which are believed to contribute to endotoxin transport and detoxification. The plasma levels of α₂-macroglobulin and transferrin, the major transport proteins, as well as the levels of IgG, IgA and IgM and apoprotein A were not significantly correlated to the neutralizing capacity. Only the apoprotein B, the major apoprotein of the low density lipoprotein fraction shows a significant correlation. Together with previously published results it should be concluded that low density lipoproteins are involved in the endogenous endotoxin-neutralizing reaction occuring in human plasma, at least when high doses of endotoxin are administered. Nevertheless the endotoxinneutralizing reaction seems to be a very complex multistep process.