A Novel Recombinant Peste des Petits Ruminants-Canine Adenovirus Vaccine Elicits Long-Lasting Neutralizing Antibody Response against PPR in Goats

Abstract

BackgroundPeste des petits ruminants (PPR) is a highly contagious infectious disease of goats, sheep and small wild ruminant species with high morbidity and mortality rates. The Peste des petits ruminants virus (PPRV) expresses a hemagglutinin (H) glycoprotein on its outer envelope that is crucial for viral attachment to host cells and represents a key antigen for inducing the host immune response.Methodology/Principal FindingsTo determine whether H can be exploited to generate an effective PPRV vaccine, a replication-competent recombinant canine adenovirus type-2 (CAV-2) expressing the H gene of PPRV (China/Tibet strain) was constructed by the in vitro ligation method. The H expression cassette, including the human cytomegalovirus (hCMV) promoter/enhancer and the BGH early mRNA polyadenylation signal, was inserted into the SspI site of the E3 region, which is not essential for proliferation of CAV-2. Infectious recombinant rCAV-2-PPRV-H virus was generated in transfected MDCK cells and used to immunize goats. All vaccinated animals produced antibodies upon primary injection that were effective in neutralizing PPRV in vitro. Higher antibody titer was obtained following booster inoculation, and the antibody was detectable in goats for at least seven months. No serious recombinant virus-related adverse effect was observed in immunized animals and no adenovirus could be isolated from the urine or feces of vaccinated animals. Results showed that the recombinant virus was safe and could stimulate a long-lasting immune response in goats.Conclusions/SignificanceThis strategy not only provides an effective PPR vaccine candidate for goats but may be a valuable mean by which to differentiate infected from vaccinated animals (the so-called DIVA approach).

Future research to underpin successful peste des petits ruminants virus (PPRV) eradication

“…This is especially useful in situations where surveillance is being implemented at the same time as vaccination. In recent years several such vaccines have been successfully developed, particularly using adenovirus [52][53][54][55] and goat/ sheep pox vectors [56][57][58], and some have been tested for efficacy in conventional PPR challenge studies; however, their capacity for long-term protection (up to 2 years) has yet to be determined. For vectored vaccines, the presence of pre-existing immunity against the vector, i.e.…”

Advances in peste des petits ruminants vaccines

“…Replication-deficient adenovirus 5 (Ad5) is considered as a better recombinant vector for use in small ruminants because unlike human beings these animals lack any pre-existing immunity to this vector (Thacker et al, 2009). Like live-attenuated PPRV vaccine, immunization of goats with Ad-H alone or in combination with an Ad-F have been found to induce potent antibody and cell mediated immune response (Herbert et al, 2014;Qin et al, 2012;Wang et al, 2013) though combination of Ad-H and Ad-F induced better protection than the Ad-H or Ad-F alone (Holzer et al, 2016b).…”

Modeling Peste des Petits Ruminants (PPR) Disease Propagation and Control Strategies Using Memoryless State Transitions

“…Vaccination is an effective means of controlling PPR (Diallo, 2006 (Qin et al, 2012). There are a variety of vaccines available to veterinarians with most vaccines conferring immunity for at least three years, which is longer than the economic life of ruminants (Sen et al, 2010).…”