A Preliminary Study of a Lettuce-Based Edible Vaccine Expressing the Cysteine Proteinase of Fasciola hepatica for Fasciolosis Control in Livestock.

Agnieszka Wesołowska,Małgorzata Kesik-Brodacka,Halina Wedrychowicz,Luiza Jedlina,Katarzyna Basałaj,Monika Kozak Ljunggren,Andrzej Legocki

doi:10.3389/fimmu.2018.02592

Abstract

Oral vaccination with edible vaccines is one of the most promising approaches in modern vaccinology. Edible vaccines are an alternative to conventional vaccines, which are typically delivered by injection. Here, freeze-dried transgenic lettuce expressing the cysteine proteinase of the trematode Fasciola hepatica (CPFhW) was used to orally vaccinate cattle and sheep against fasciolosis, which is the most important trematode disease due to the parasite's global distribution, wide spectrum of host species and significant economic losses of farmers. In the study, goals such as reducing the intensity of infection, liver damage and F. hepatica fecundity were achieved. Moreover, we demonstrated that the host sex influenced the outcome of infection following vaccination, with female calves and male lambs showing better protection than their counterparts. Since differences occurred following vaccination and infection, different immunization strategies should be considered for different sexes and host species when developing new control methods. The results of the present study highlight the potential of oral vaccination with plant-made and plant-delivered vaccines for F. hepatica infection control.

Highlights

Fasciolosis is a chronic disease with a global distribution
Vaccinated calves showed a significant reduction in liver fluke recovery of 56.2%
When the data were analyzed by sex, the female cattle had higher anti-CPFhW IgG levels from 6 weeks post-infection (WPI) to the end of the experiment when compared with their male counterparts (Figure S4)

Summary

Introduction

Fasciolosis is a chronic disease with a global distribution. This disease is a major cause of morbidity and mortality in domestic ruminants, such as cattle and sheep, and results in an estimated loss of approximately US$3 billion annually to the global agricultural sector [1]. Drugs may provide a cure for liver fluke infection; due to the continuous development of drug-resistant parasites and high reinfection rates in areas where Fasciola hepatica exposure is a regular occurrence, new control strategies against fasciolosis are needed. Many vaccine studies in ruminants using different candidate antigens, including the leading candidates fatty acid binding protein, glutathione-s-transferase, leucine aminopeptidase, and cathepsin (Cat) L1 and L2, have shown promise [2].

Methods

Results

Conclusion