The isotonic protein mixture suppresses Porcine Epidemic Diarrhea Virus excretion and initiates intestinal defensive response

Abstract

The intestinal barrier is an extremely important structure to maintain piglet health. However, various enteropathogens, including coronaviruses, are especially aggressive factors for intestinal barrier destruction. That is why the aim of the present study was to clarify the role of adhesive proteins in the piglet intestinal barrier affected by coronavirus enteric infection. For this purpose, we formed two groups of 14-day-old piglets to construct an experimental model of enteric disorder. Each animal was infected with the porcine epidemic diarrhea virus (PEDV) at a dose of 104 virions. The piglets of the experimental group were additionally fed of isotonic protein mixture (IPM). The intensity of the infectious process was assessed by the duration of virus elimination from the piglets’ body, the amount of excreted virus, and the immune response efficacy. The level of immune response was detected by specific IgG in the blood serum and α-interferon (IFN-α) in the intestinal tissues. The intestinal barrier integrity was assessed by the level of proteins in the tissues that form tight intercellular contacts especially E-cadherin and fibronectin in the duodenum. The results have shown variability in the duration of the PEDV elimination period in piglets’ faeces. The exposure to IPM provides a protective effect that enhances the recovery processes in the intestinal tissues. That was also reflected in an increase in the amount of E-cadherin and fibronectin in the duodenum. Furthermore, the isotonic protein mixture’s protective effect was reflected in an increase in the body’s immune responses at the intestinal level. This effect was evidenced by an increase in the amount of IFN-α in the duodenum and an increase in the synthesis of specific IgG in the blood serum. Obtained results showed a protective effect of IPM treatment while the intestinal barrier and immune responses were enhanced. IPM treatment induced about a 10 times decrease in the amount of PEDV excreted in the faeces of experimental animals and contributed to a 7-day reduction in the virus excretion period.

Keywords

• pedv excretion
• intestinal barrier
• e-cadherin
• fibronectin