Experimental Research Of Biological Effect On Anti-lipopolysaccharide IgY Antibody

The barrier function of intestinal tract always descents at different level after burned, including mechanical barrier, biologic barrier and immunologic barrier. There are some erosion and ulcer on the intestinal mucosa and dysbacteriosis appears. The level of secretory IgA (sIgA) descents after the immune system function decreases. The endotoxin of the intestine often translocates from the intestine to blood circulation. It is one of the important reasons that systemic infection and multiple organ failure occurred. At present, no special operative drugs antagonizing LPS could be applied at clinic. In recent years, it was found that there were abundant IgG sourcing from serum in egg yolk and was named IgY, which could antagonize corresponding antigens perfectly. We hope to obtain a specific anti-LPS IgY from the eggs.Using the WD antibody purification method, specific anti-LPS IgY was obtained from the egg yolk of hens immunized with LPS. Innocuity of IgY was certified by measuring LD50 and contrasting with international six grades code, which frequently used to evaluate toxicity dimension of a compound after acute toxicity experiments in toxicology. In vitro, IgY and LPS had good dose-effect relation when their concentration ratio was 15:1. The competition-repression experiments showed that IgY could inhibit both the adhesion and injury role of LPS to cultured human umbilical vein endothelial cell. The main results were that fluorescence intensity of the cells decreased and the LDH production in the cultured medium decreased significantly.After IgY had been orally administrated to Kunming-species mice, which had been made animal model of post-burned intestinal endotoxemia, the results showed that IgY could decrease the death rate of the experimental mice significantly. Furthermore, after the therapy with IgY, the contents of LPS, DAO and TNF-αhad decreased significantly in mice plasma. Pathological sections of the ileal mucous membrane showed that IgY also had protection action to intestinal mucosa. From the experiments in vitro and in vivo, we could draw a conclusion that IgY either antagonized LPS better or had prevention and treatment action to intestinal endotoxemia.