The effects of intraperitoneal vaccination with Lawsonia intracellularis on immune responses in weaner pigs

摘要

Oral vaccines reliably induce immunity against enteric pathogens by directly accessing mucosal surfaces of the intestine and draining mesenteric lymph nodes (Muir et al, 1995). In pigs, proliferative enteropathy (PE) is an important enteric disease caused by the Gram-negative bacterium Lawsonia intracellularis. Oral and intramuscular vaccination with L. intracellularis induced specific responses and protection against challenge (Nogueira et al, 2013). Previously, intraperitoneal (IP) vaccination protected pigs from lung lesions due to Mycoplasma hyopneumoniae (Djordjevic et al, 1997). An immune correlate which correlates with the successful induction of mucosal immunity and predicts protection against L. intracellularis has been difficult to measure. Since the route of vaccination is one factor that determines the magnitude, duration and quality of immune response at mucosal sites, we hypothesised that IP vaccination should produce immune responses similar to those induced by oral administration of L. intracellularis.