The aim of this study was to assess the immune response and the protective efficacy elicited by the vaccination with the recombinant Fasciola hepatica myosin regulatory light chain (FhrMRLC) in Adjuplex® adjuvant against the infection with F. hepatica in rats. Four groups of 15 animals each were used for the study, one group was immunized with the recombinant F.
View Article and Find Full Text PDFVet Immunol Immunopathol
November 2019
DNA vaccination in large animals has often been associated with poor immunogenicity, consequently several approaches have been evaluated to enhance its efficacy. Here, we tested a cDNA encoding a phosphoglycerate kinase from Fasciola hepatica (cDNA-FhPGK/pCMV) as a vaccine against ovine fasciolosis and investigated whether a DNA prime/protein boost regime or CTLA-4 (cytotoxic lymphocyte antigen 4) mediated targeting improved DNA vaccine efficacy. No statistically significant differences in the cellular responses were seen in either vaccine trial when compared with the respective control groups.
View Article and Find Full Text PDFMonoclonal antibodies have a wide range of applications in basic and applied research as well as in the medical and pharmaceutical industries. Phage display antibody libraries offer an alternative to hybridoma technology for the generation of monoclonal antibodies and can be applied to high-throughput screening and facilitate the generation of novel antibodies. Despite their utility in several fields of research there has been limited application of antibody libraries in the study of trematode parasites.
View Article and Find Full Text PDFPhage display technology to produce recombinant monoclonal antibodies or antibody fragments permits the identification of sought after antibodies in short time frames at low cost along with direct and rapid selection for antibody characteristics. Monoclonal antibodies can facilitate the identification and characterisation of parasite molecules that function at the host-parasite interface to help understand at the molecular level the biology of the parasite and disease progression, which often leads to new drug targets, diagnostic antigens or vaccine candidates. The trematode Fasciola hepatica is an important veterinary and human parasite.
View Article and Find Full Text PDFOral 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 (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.
View Article and Find Full Text PDFFasciola hepatica infection continues to be a major problem in the agriculture sector, particularly in sheep and cattle. Cathepsin L and B proteases are major components of the excretory/secretory material of the parasite, and their roles in several important aspects of parasite invasion and survival has led to their use as targets in rational vaccine design. Previous studies in rats demonstrated that the use of stage-specific antigens, cathepsin B2 and cathepsin L5, as part of a multivalent vaccine, was able to confer significant protection against challenge.
View Article and Find Full Text PDFMost animal research is less evidence-based for females, with the majority of studies conducted on males. Since immune responses vary between males and females, sexual dimorphism in immunity contributes, among other things, to sex-based differences post-vaccination. However, the issue of sex effects in animal vaccine research is rarely considered in vaccine study design.
View Article and Find Full Text PDFNo licensed vaccine is currently available for prevention of Fasciola hepatica infections. However, considering the alarming increase in drug resistance, there is an urgent need for a safe and fully effective vaccine against fasciolosis. Here, we tested if cathepsins L (FhCL3-1, FhCL3-2) and B (FhCB3) secreted by juvenile liver flukes are viable vaccine targets when delivered alone or in combination in a rat model.
View Article and Find Full Text PDFLymphocyte responses in the blood, peritoneal fluid and both mesenteric and hepatic lymph nodes of cDNA-FhPGK/pCMV vaccinated and/or Fasciola hepatica infected rats of both sexes were investigated to provide an insight into the immune responses that develop in different body compartments. The immune response that developed in cDNA-FhPGK/pCMV vaccinated females contributed to partial protection against F. hepatica infection (54% reduction in fluke recovery), while more liver flukes were found in the livers and bile ducts of cDNA-FhPGK/pCMV vaccinated male rats than in unvaccinated animals (increase of 13%).
View Article and Find Full Text PDFBackground: Cysteine proteinases of Fasciola hepatica are important candidates for vaccine antigens because of their role in fluke biology and host-parasite relationships. In our previous experiments, we found that a recombinant cysteine proteinase cloned from adult F. hepatica (CPFhW) can protect rats against liver fluke infections when it is administered intramuscularly or intranasally in the form of cDNA.
View Article and Find Full Text PDFHookworms, a group to which Ancylostoma ceylanicum belongs, are gastrointestinal nematodes that infect more than 700 million people around the world. They are a leading cause of anemia in developing countries. In order to effectively prevent hookworm infections research is conducted to develop an effective vaccine using recombinant antigens of the parasite.
View Article and Find Full Text PDFImmune responses of rats and sheep following vaccination with cDNA encoding phosphoglycerate kinase of Fasciola hepatica (cDNA-FhPGK/pCMV) and F. hepatica infection were investigated in the present study. cDNA-FhPGK/pCMV vaccinated female Sprague-Dawley rats were better protected by vaccination than their male counterparts - 48% reduction in fluke burden for females and no protection for males when compared with appropriate infection control groups.
View Article and Find Full Text PDFHookworms are intestinal nematodes that infect up to 740 million people, mostly in tropical and subtropical regions. Adult worms suck blood from damaged vessels in the gut mucosa, digesting hemoglobin using aspartic-, cysteine- and metalloproteases. Targeting aspartic hemoglobinases using drugs or vaccines is therefore a promising approach to ancylostomiasis control.
View Article and Find Full Text PDFDemands for effective vaccines to control parasitic diseases of humans and livestock have been recently exacerbated by the development of resistance of most pathogenic parasites to anti-parasitic drugs. Novel genomic and proteomic technologies have provided opportunities for the discovery and improvement of DNA vaccines which are relatively easy as well as cheap to fabricate and stable at room temperatures. However, their main limitation is rather poor immunogenicity, which makes it necessary to couple the antigens with adjuvant molecules.
View Article and Find Full Text PDFFasciola hepatica is a liver fluke that infects 2.4 million of people and causes great economical loss in animal production. To date a 100% effective vaccine has not been developed and the disease is controlled by drug therapy.
View Article and Find Full Text PDFHookworms are blood feeding intestinal nematodes that infect more than 500 million people and cause iron deficiency anemia. Infected children suffer from physical and cognitive growth retardation. Because of potential anthelminthic drug resistance, the need for vaccine development is urgent.
View Article and Find Full Text PDFUrinary creatinine to serum creatinine (UCr/SCr) ratio and renal failure index (RFI) are useful indices of renal damage. Both UCr/SCr ratio and RFI are used in differentiation between prerenal azotaemia and acute tubular necrosis. In this work the authors calculated the UCr/SCr ratio and RFI in dogs infected with Babesia canis and the values of these indices in azotaemic dogs infected with the parasite.
View Article and Find Full Text PDFFasciola hepatica infections cause significant global problems in veterinary and human medicine, including causing huge losses in cattle and sheep production. F. hepatica host infection is a multistage process and flukes express papain-like cysteine proteases, termed cathepsins, which play pivotal roles in virulence through host entry, tissue migration and immune evasion.
View Article and Find Full Text PDFThe liver fluke Fasciola hepatica infects a wide range of hosts, and has a considerable impact on the agriculture industry, mainly through infections of sheep and cattle. Further, human infection is now considered of public health importance and is hyperendemic in some regions. The fluke infection causes considerable damage to the hosts' liver.
View Article and Find Full Text PDFNot only do males and females of many species vary in their responses to certain parasitic infections, but also to treatments such as vaccines. However, there are very few studies investigating differences among sexes following vaccination and infection. Here we demonstrate that female Sprague-Dawley rats vaccinated with cDNA encoding a recently discovered cysteine proteinase of Fasciola hepatica (FhPcW1) develop considerably lower liver fluke burdens after F.
View Article and Find Full Text PDFUncinaria stenocephala belongs to Ancylostomatidae family. Members of this family - hookworms - infect millions of people and animals worldwide. U.
View Article and Find Full Text PDFIn this study an increased SUSPPUP ratio and fractional excretion of potassium in dogs infected with Babesia canis suggested mineralocorticoid excess in canine babesiosis. A significant increase in strong monovalent electrolyte fractional excretions in azotaemic dogs infected with B. canis probably resulted from acute tubular necrosis.
View Article and Find Full Text PDFAncylostoma ceylanicum belongs to a group of soil-transmitted helminths, which infect almost 576 mln people worldwide and are a major cause of anaemia and malnutrition. Upon contact with a permissive host, third-stage larvae (L3) residing in the environment become activated larvae (ssL3), a process associated with changes in the profile of gene expression. Ancylostoma secreted proteins (ASPs) are the major proteins secreted during larvae activation and play a crucial role in hookworm adaptation to parasitism.
View Article and Find Full Text PDFFasciolosis is a considerable veterinary problem, causing significant economic losses to livestock production and the food industry. Research in the area of Fasciola hepatica infection immunology is necessary to improve our knowledge about immunological mechanism evoked by the parasite and to develop new control strategies against liver fluke. In this present paper we analyzed the expression levels of cytokines in rats infected with F.
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