Fasciola hepatica vaccine: We may not be there yet but we’re on the right road

Abstract

Major advances have been made in identifying potential vaccine molecules for the control of fasciolosis in livestock but we have yet to reach the level of efficacy required for commercialisation. The pathogenesis of fasciolosis is associated with liver damage that is inflicted by migrating and feeding immature flukes as well as host inflammatory immune responses to parasite-secreted molecules and tissue damage alarm signals. Immune suppression/modulation by the parasites prevents the development of protective immune responses as evidenced by the lack of immunity observed in naturally and experimentally infected animals. In our opinion, future efforts need to focus on understanding how parasites invade and penetrate the tissues of their hosts and how they potentiate and control the ensuing immune responses, particularly in the first days of infection. Emerging ‘omics’ data employed in an unbiased approach are helping us understand liver fluke biology and, in parallel with new immunological data, to identify molecules that are essential to parasite development and accessible to vaccine-induced immune responses.

A mucin-like peptide from Fasciola hepatica instructs dendritic cells with parasite specific Th1-polarizing activity

“…Effective chemotherapies are available, but, due to the cost of the treatment and the emergence of resistant strains13, alternative methods to control infection such as vaccination, are needed1415. To date, vaccination trials with either purified native or recombinant F. hepatica proteins have reported a wide range of protection (30–89%) in ruminants151617. Interestingly, it has been proposed that induction of a robust Th1 response could protect the host not only from the infection1518 but also from bystander co-infections by down-regulating Th2 regulatory immunity19.…”

Wat zijn de mogelijkheden om een leverbotinfectie van melkvee te voorkomen?

“…Het is niet te verwachten dat nieuwe diergeneesmiddelen tegen leverbot op (korte of middellange) termijn op de markt zullen komen. Een klein lichtpuntje is dat op dit moment een aantal onderzoeken lopen naar de ontwikkeling van een vaccin tegen leverbot (Dalton et al, 2013;Molina-Hernández et al, 2015;Toet et al, 2014 Behandel dieren indien nodig en toegestaan  Behandel besmet jongvee pas vanaf twee weken na opstallen met een middel met als werkzame stof triclabendazol, mits er op het bedrijf geen resistentie bestaat tegen deze werkzame stof  Behandel bij een flinke besmetting van het melkgevende vee, in overleg met de dierenarts en binnen de cascaderegeling, het gehele melkkoppel vanaf twee weken na opstallen met een middel met als werkzame stof triclabendazol, mits er op het bedrijf geen resistentie bestaat tegen deze werkzame stof  Controleer via mestonderzoek of de behandeling effect heeft gehad VII.…”

Comparison between in-house indirect ELISA and Dot-ELISA for the diagnosis of Fasciola gigantica in cattle

“…Fasciola hepatica and Fasciola gigantica are the most commonly parasites caused Fasciolosis (Dolton 1998). The pathogenicity of fasciolosis is based on expansion of lesions in the liver of host by migrating and feeding immature flukes as well as host immune responses to parasite secreted molecules and tissue damage alarm signals (Molina-Hernández et al 2015). In general clinical signs appear three weeks postinfection.…”