Efficacy of specific IgY for treatment of lipopolysaccharide-induced endotoxemia using a mouse model

Aims: To estimate the efficacy of specific egg yolk immunoglobulin (IgY) for the treatment of lipopolysaccharide (LPS)-induced endotoxemia using a mouse model. Methods and Results: Specific IgY was obtained from the yolk of hens immunized with formaldehyde-killed Escherichia coli O111 and showed a high binding activity to LPS when subjected to an ELISA. Endotoxemia was induced in mice by intraperitoneal injection of LPS at a dose of 20 mg kg(-1) for measuring survival rate and 10 mg kg(-1) for cytokine measurement. The survival rate of mice treated with 200 mg kg(-1) specific IgY or 5 mg kg(-1) dexamethasone was 70% while none of the mice in the normal saline-treated group survived more than 7 days. Specific IgY significantly (P < 0 05) decreased tumour necrosis factor-alpha (TNF-alpha) level and increased interleukin-10 (IL-10) level in the serum of endotoxemia mice. Specific IgY had less of an effect on TNF-alpha than dexamthasone, while its effect on increasing IL-10 was stronger than dexamethasone. Haematoxylin and eosin-stained sections indicated that IgY attenuated the damage to the lung and liver observed in mice with endotoxemia. Conclusions: The specific IgY increased the survival rate of mice with endotoxemia induced by LPS, down-regulated TNF-alpha and up-regulated IL-10 in serum and attenuated the extent of damage to the lung and liver. Significance and Impact of the Study: The specific IgY has potential for the treatment of LPS-induced endotoxemia.