Biology subjects

Prenafeta, A.

Publications and source records attributed to Prenafeta, A..

4 recordsLinked to original sources

bioRxiv2024

Immunological response against bovine viral diarrhoea virus (BVDV) types 1 and 2 after vaccination with DIVENCE (R), measured by ELISA and serum neutralisation on serum and milk samples

BackgroundA novel subunit vaccine, DIVENCE(R), comprises different bovine respiratory and reproductive antigens, including BVDV-1 E2 recombinant glycoprotein and BVDV-2 E2 recombinant glycoprotein. This study evaluated the immune response against BVDV-1 and 2 generated by DIVENCE(R) over the long term in different strains. MethodsTwo different studies were conducted to assess the immune response induced by DIVENCE(R). In the first study, 20 seronegative young calves (55-104 days of age) were randomly distributed into the vaccinated or control group. All animals were given four intramuscular doses (D0, D21, D204 and D570) of 2 mL DIVENCE(R) or phosphate-buffered saline (PBS). Blood samples were collected to assess BVDV serum antibodies (ELISA) and neutralising antibodies (SN) against BVDV-1 and BVDV-2. In the second trial, heifers (from 10 months of age until calving) and cows (between first and seventh calving) were included and assigned to the vaccinated and control groups. Three different farms were enrolled in the study. The administration regimen was the same as described in the first study. Blood samples were collected from 32 random animals on each farm (16 vaccinated and 16 control animals). Additionally, bulk tank milk samples from each farm were obtained at different time-points and individual milk samples were obtained from vaccinated and control animals. The immune response against BVDV was analysed in serum and milk samples using different ELISA kits. Neutralising antibodies induced by DIVENCE(R) against different BVDV isolates from Europe and the Americas were also assessed in this trial. ResultsOverall, DIVENCE(R) induced high levels of total antibodies (ELISA) and neutralising antibodies against BVDV-1 and BVDV-2. These values were significantly (p<0.05) greater than the control group from 21 days after the second dose (D42) until the end of the study (D591). The high antibody levels, particularly after the third dose, were similar to those that described efficacy against experimental challenges of BVDV-1 and 2 in pregnant animals. In the field trial, similar results were observed in terms of total antibodies (ELISA) against BVDV, and no induction of anti-p80 antibodies was observed in vaccinated animals at any time. Additionally, analyses on individual and bulk tank milk samples also confirmed that no anti-p80 antibodies were induced in vaccinated animals. Furthermore, high levels of neutralising antibodies were observed against different BVDV isolates from Europe and the Americas. ConclusionThe DIVENCE(R) vaccine induced a strong immune response against BVDV-1 and BVDV-2, and this response allows infected and vaccinated animals to be differentiated (DIVA vaccine).

immunology↗

bioRxiv2024

Fetal protection against bovine viral diarrhea virus types 1 and 2 after vaccination of the dam with the DIVENCE vaccine

The aim of this study was to demonstrate the efficacy of DIVENCE, a vaccine against BVDV types 1 and 2 (BVDV-1 and BVDV-2) transplacental infection, following a booster regimen in heifers. Calves of two-to-three months of age were given two intramuscular doses three weeks apart and a booster vaccine six months later. Efficacy was evaluated by means of a challenge with virulent BVDV-1 or BVDV-2 administered via the intranasal route at 85 days of gestation. Clinical signs, serology, viral shedding, WBC count and viremia were monitored after the challenge. Sixty-six days post-challenge, the fetuses were assessed for BVDV to detect transplacental infection. The results demonstrate a reduction in hyperthermia, leukopenia, viral shedding, and viremia in vaccinated animals post-challenge with BVDV-1 and BVDV-2. Most importantly, DIVENCE administered prior to breeding protected 94% of the fetuses against BVDV transplacental infection overall across both challenge trials (BVDV-1 and BVDV-2).

immunology↗

bioRxiv2022

Preclinical efficacy, safety, and immunogenicity of PHH-1V, a second-generation COVID-19 vaccine, in non-human primates

SARS-CoV-2 emerged in December 2019 and quickly spread worldwide, continuously striking with an unpredictable evolution. Despite the success in vaccine production and mass vaccination programmes, the situation is not still completely controlled, and therefore accessible second-generation vaccines are required to mitigate the pandemic. We previously developed an adjuvanted vaccine candidate coded PHH-1V, based on a heterodimer fusion protein comprising the RBD domain of two SARS-CoV-2 variants. Here, we report data on the efficacy, safety, and immunogenicity of PHH-1V in cynomolgus macaques. PHH-1V prime-boost vaccination induces high levels of RBD-specific IgG binding and neutralising antibodies against several SARS-CoV-2 variants, as well as a balanced Th1/Th2 cellular immune response. Remarkably, PHH-1V vaccination prevents SARS-CoV-2 replication in the lower respiratory tract and significantly reduces viral load in the upper respiratory tract after an experimental infection. These results highlight the potential use of the PHH-1V vaccine in humans, currently undergoing Phase III clinical trials.

immunology↗

bioRxiv2021

Preclinical efficacy, safety, and immunogenicity of PHH-1V, a second-generation COVID-19 vaccine candidate based on a novel recombinant RBD fusion heterodimer of SARS-CoV-2.

Current C0VID-19 vaccines have been associated with a decline in infection rates, prevention of severe disease and a decrease in mortality rates. However, SARS-CoV-2 variants are continuously evolving, and development of new accessible COVID-19 vaccines is essential to mitigate the pandemic. Here, we present data on preclinical studies in mice of a receptor-binding domain (RBD)-based recombinant protein vaccine (PHH-1V) consisting of an RBD fusion heterodimer comprising the B.1.351 and B.1.1.7 SARS-CoV-2 variants formulated in SQBA adjuvant, an oil-in-water emulsion. A prime-boost immunisation with PHH-1V in BALB/c and K18-hACE2 mice induced a CD4+ and CD8+ T cell response and RBD-binding antibodies with neutralising activity against several variants, and also showed a good tolerability profile. Significantly, RBD fusion heterodimer vaccination conferred 100% efficacy, preventing mortality in SARS-CoV-2 infected K18-hACE2 mice, but also reducing Beta, Delta and Omicron infection in lower respiratory airways. These findings demonstrate the feasibility of this recombinant vaccine strategy.

immunology↗