Immunological responses and potency of the EG95NC- recombinant sheep vaccine against cystic echinococcosis.

Cystic echinococcosis (CE) is a zoonotic disease caused by the cestode parasite Echinococcus granulosus. The disease has an important impact on human health as well as economic costs including the cost of treatment as well as loss of productivity for the livestock industry. In many parts of the world where the disease is endemic, sheep and other livestock play an important role in the parasite's transmission. A vaccine to protect livestock against CE can be effective in reducing transmission and economic costs of the disease. A recombinant antigen vaccine has been developed against infection with E. granulosus (EG95) which could potentially be used to reduce the level of E. granulosus transmission and decrease the incidence of human infections. Further development of the EG95 recombinant vaccine as a combined product with clostridial vaccine antigens is one potential strategy which could improve application of the hydatid vaccine by providing an indirect economic incentive to livestock owners to vaccinate against CE. In this study we investigated the efficacy of the EG95 recombinant vaccine produced in Morocco by vaccination of sheep, including a combined vaccine incorporating EG95 and clostridia antigens. Vaccination with EG95 either as a monovalent vaccine or combined with clostridia antigens, protected sheep against a challenge infection with E. granulosus eggs and induced a strong, long lasting, and specific antibody response against the EG95 antigen.

Comparative evaluation of three capripoxvirus-vectored peste des petits ruminants vaccines.

Sheep and goat pox (SGP) with peste des petits ruminants (PPR) are transboundary viral diseases of small ruminants that cause huge economic losses. Recombinant vaccines that can protect from both infections have been reported as a promising solution for the future. SGP was used as a vector to express two structural proteins hemagglutinin or the fusion protein of PPRV. We compared immunity conferred by recombinant capripoxvirus vaccines expressing H or F or both HF. Safety and efficacy were evaluated in goats and sheep. Two vaccine doses were tested in sheep, 104.5TCDI50 in 1ml dose was retained for the further experiment. Results showed that the recombinant HF confers an earlier and stronger immunity against both SGP and PPR. This recombinant vaccine protect also against the disease in exposed and unexposed sheep. The potential Differentiating Infected from Vaccinated Animals of recombinant vaccines is of great advantage in any eradication program.

Vaccination Against Hydatidosis: Molecular Cloning and Optimal Expression of the EG95NC- Recombinant Antigen in Escherichia coli.

Cystic echinococcosis (CE) is a widely distributed zoonosis that is highly endemic in the Mediterranean basin. The disease represents a serious public health threat and causes economic losses. The parasite life-cycle involves dogs and ruminants as definitive and intermediate hosts; humans are accidently infected, causing serious clinical issues. Vaccination of ruminants and dog treatments represent the most efficient measures to prevent parasite transmission. The recombinant protein vaccine, EG95, has been used successfully in sheep vaccine trials against CE in several countries. In this study, we expressed the modified antigen, EG95NC-GST, in Escherichia coli for use as a vaccine against Echinococcus granulosus in ruminants. We tested three different media formulations for E. coli culture and established for each culture conditions for optimal levels of soluble EG95 expression. The results demonstrate that SOC and TB media provided high yields in cell density and EG95 protein expression. Purification of the recombinant protein with affinity chromatography (using FPLC) was also performed to increase the purity of the EG95NC--GST antigen.