RESUMEN
Enhancing livestock biosecurity is critical to safeguard the livelihoods of farmers, global and local economies, and food security. Vaccination is fundamental to the control and prevention of exotic and endemic high-priority infectious livestock diseases. Successful implementation of vaccination in a biosecurity plan is underpinned by a strong understanding of correlates of protection-those elements of the immune response that can reliably predict the level of protection from viral challenge. While correlates of protection have been successfully characterized for many human viral vaccines, for many high-priority livestock viral diseases, including African swine fever and foot and mouth disease, they remain largely uncharacterized. Current literature provides insights into potential correlates of protection that should be assessed during vaccine development for these high-priority mammalian livestock viral diseases. Establishment of correlates of protection for biosecurity purposes enables immune surveillance, rationale for vaccine development, and successful implementation of livestock vaccines as part of a biosecurity strategy.
Asunto(s)
Ganado , Vacunación , Vacunas Virales , Animales , Ganado/inmunología , Ganado/virología , Vacunas Virales/inmunología , Vacunación/veterinaria , Virosis/prevención & control , Virosis/inmunología , Virosis/veterinaria , Porcinos , Fiebre Aftosa/prevención & control , Fiebre Aftosa/inmunología , Fiebre Porcina Africana/prevención & control , Fiebre Porcina Africana/inmunología , HumanosRESUMEN
Foot and mouth disease (FMD) is a highly contagious infection caused by FMD-virus (FMDV) that affects livestock worldwide with significant economic impact. The main strategy for the control is vaccination with FMDV chemically inactivated with binary ethylenimine (FMDVi). In FMDV infection and vaccination, B cell response plays a major role by providing neutralizing/protective antibodies in animal models and natural hosts. Extracellular vesicles (EVs) and small EVs (sEVs) such as exosomes are important in cellular communication. EVs secreted by antigen-presenting cells (APC) like dendritic cells (DCs) participate in the activation of B and T cells through the presentation of native antigen membrane-associated to B cells or by transferring MHC-peptide complexes to T cells and even complete antigens from DCs. In this study, we demonstrate for the first time that APC activated with the FMDVi O1 Campos vaccine-antigens secrete EVs expressing viral proteins/peptides that could stimulate FMDV-specific immune response. The secretion of EVs-FMDVi is a time-dependent process and can only be isolated within the first 24 h post-activation. These vesicles express classical EVs markers (CD9, CD81, and CD63), along with immunoregulatory molecules (MHC-II and CD86). With an average size of 155 nm, they belong to the category of EVs. Studies conducted in vitro have demonstrated that EVs-FMDVi express antigens that can stimulate a specific B cell response against FMDV, including both marginal zone B cells (MZB) and follicular B cells (FoB). These vesicles can also indirectly or directly affect T cells, indicating that they express both B and T epitopes. Additionally, lymphocyte expansion induced by EVs-FMDVi is greater in splenocytes that have previously encountered viral antigens in vivo. The present study sheds light on the role of EVs derived from APC in regulating the adaptive immunity against FMDV. This novel insight contributes to our current understanding of the immune mechanisms triggered by APC during the antiviral immune response. Furthermore, these findings may have practical implications for the development of new vaccine platforms, providing a rational basis for the design of more effective vaccines against FMDV and other viral diseases.
Asunto(s)
Células Presentadoras de Antígenos , Antígenos Virales , Linfocitos B , Vesículas Extracelulares , Virus de la Fiebre Aftosa , Fiebre Aftosa , Vacunas Virales , Animales , Virus de la Fiebre Aftosa/inmunología , Vesículas Extracelulares/inmunología , Linfocitos B/inmunología , Fiebre Aftosa/inmunología , Fiebre Aftosa/prevención & control , Células Presentadoras de Antígenos/inmunología , Células Presentadoras de Antígenos/metabolismo , Antígenos Virales/inmunología , Vacunas Virales/inmunología , Proteínas Virales/inmunología , Activación de Linfocitos/inmunología , Células Dendríticas/inmunología , Presentación de Antígeno/inmunologíaRESUMEN
VP1, a major immunogenic protein of foot-and-mouth disease virus (FMDV), facilitates viral attachment and entry into host cells. VP1 possesses critical epitope sequences responsible for inducing neutralizing antibodies but its expression using Saccharomyces cerevisiae has been hampered despite evidence that the presence of VP1 does not negatively impact the yeast's biology. In this study, we fused proteins to enhance VP1 expression using S. cerevisiae. Among short P1 chimeras containing VP1 including VP3-VP1 and VP2-VP1, VP3-VP1 fusion proteins showed higher expression levels than VP2-VP1. We subsequently designed new fusion proteins, of which 20 amino acids of N-terminal VP3 fused with VP1-Co1 (referred to 20aaVP3-VP1-Co1) showed the highest expression level. Lowering the culture temperature from 30 °C to 20 °C further enhanced fusion protein production. The highest expression level of 20aaVP3-VP1-Co1 was estimated to be 7.7â¯mg/L, which is comparable to other heterologous proteins produced using our S. cerevisiae expression system. Oral administration of the cell expressing 20aaVP3-VP1-Co1 induced VP1-specific IgG and IgA responses in mice. The S. cerevisiae-expressed 20aaVP3-VP1-Co1 fusion protein induced a significant immune response to the FMDV structural epitope protein, which opens the possibility of an oral FMDV vaccine.
Asunto(s)
Anticuerpos Antivirales , Proteínas de la Cápside , Virus de la Fiebre Aftosa , Fiebre Aftosa , Proteínas Recombinantes de Fusión , Saccharomyces cerevisiae , Vacunas Virales , Animales , Virus de la Fiebre Aftosa/inmunología , Virus de la Fiebre Aftosa/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/inmunología , Proteínas de la Cápside/genética , Proteínas de la Cápside/inmunología , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/genética , Ratones , Vacunas Virales/inmunología , Vacunas Virales/administración & dosificación , Vacunas Virales/genética , Anticuerpos Antivirales/sangre , Fiebre Aftosa/prevención & control , Fiebre Aftosa/inmunología , Administración Oral , Inmunización , Femenino , Codón , Anticuerpos Neutralizantes/inmunología , Ratones Endogámicos BALB C , Inmunoglobulina ARESUMEN
BACKGROUND: Foot-and-mouth disease (FMD) is a devastating disease affecting cloven-hoofed animals, that leads to significant economic losses in affected countries and regions. Currently, there is an evident inclination towards the utilization of nanoparticles as powerful platforms for innovative vaccine development. Therefore, this study developed a ferritin-based nanoparticle (FNP) vaccine that displays a neutralizing epitope of foot-and-mouth disease virus (FMDV) VP1 (aa 140-158) on the surface of FNP, and evaluated the immunogenicity and protective efficacy of these FNPs in mouse and guinea pig models to provide a strategy for developing potential FMD vaccines. RESULTS: This study expressed the recombinant proteins Hpf, HPF-NE and HPF-T34E via an E. coli expression system. The results showed that the recombinant proteins Hpf, Hpf-NE and Hpf-T34E could be effectively assembled into nanoparticles. Subsequently, we evaluated the immunogenicity of the Hpf, Hpf-NE and Hpf-T34E proteins in mice, as well as the immunogenicity and protectiveness of the Hpf-T34E protein in guinea pigs. The results of the mouse experiment showed that the immune efficacy in the Hpf-T34E group was greater than the Hpf-NE group. The results from guinea pigs immunized with Hpf-T34E showed that the immune efficacy was largely consistent with the immunogenicity of the FMD inactivated vaccine (IV) and could confer partial protection against FMDV challenge in guinea pigs. CONCLUSIONS: The Hpf-T34E nanoparticles stand out as a superior choice for a subunit vaccine candidate against FMD, offering effective protection in FMDV-infected model animals. FNP-based vaccines exhibit excellent safety and immunogenicity, thus representing a promising strategy for the continued development of highly efficient and safe FMD vaccines.
Asunto(s)
Epítopos , Ferritinas , Virus de la Fiebre Aftosa , Fiebre Aftosa , Nanopartículas , Vacunas Virales , Animales , Cobayas , Fiebre Aftosa/prevención & control , Fiebre Aftosa/inmunología , Virus de la Fiebre Aftosa/inmunología , Ferritinas/inmunología , Vacunas Virales/inmunología , Epítopos/inmunología , Ratones , Femenino , Ratones Endogámicos BALB C , Proteínas Recombinantes/inmunología , Proteínas de la CápsideRESUMEN
AbstractInfectious disease dynamics operate across biological scales: pathogens replicate within hosts but transmit among populations. Functional changes in the pathogen-host interaction thus generate cascading effects across organizational scales. We investigated within-host dynamics and among-host transmission of three strains (SAT-1, -2, -3) of foot-and-mouth disease viruses (FMDVs) in their wildlife host, African buffalo. We combined data on viral dynamics and host immune responses with mathematical models to ask the following questions: How do viral and immune dynamics vary among strains? Which viral and immune parameters determine viral fitness within hosts? And how do within-host dynamics relate to virus transmission? Our data reveal contrasting within-host dynamics among viral strains, with SAT-2 eliciting more rapid and effective immune responses than SAT-1 and SAT-3. Within-host viral fitness was overwhelmingly determined by variation among hosts in immune response activation rates but not by variation among individual hosts in viral growth rate. Our analyses investigating across-scale linkages indicate that viral replication rate in the host correlates with transmission rates among buffalo and that adaptive immune activation rate determines the infectious period. These parameters define the virus's relative basic reproductive number (â0), suggesting that viral invasion potential may be predictable from within-host dynamics.
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Búfalos , Virus de la Fiebre Aftosa , Fiebre Aftosa , Animales , Búfalos/virología , Virus de la Fiebre Aftosa/inmunología , Virus de la Fiebre Aftosa/crecimiento & desarrollo , Fiebre Aftosa/transmisión , Fiebre Aftosa/virología , Fiebre Aftosa/inmunología , Interacciones Huésped-Patógeno/inmunología , Replicación Viral , Modelos BiológicosRESUMEN
Foot-and-mouth disease virus (FMDV) is a highly contagious and economically devastating pathogen that affects cloven-hoofed animals worldwide. FMDV infection causes vesicular lesions in the mouth, feet, and mammary glands, as well as severe systemic symptoms such as fever, salivation, and lameness. The pathogenesis of FMDV infection involves complex interactions between the virus and the host immune system, which determine the outcome of the disease. FMDV has evolved several strategies to evade immune recognition and elimination, such as antigenic variation, receptor switching, immune suppression, and subversion of innate and adaptive responses. This review paper summarizes the current knowledge on the pathogenesis of FMDV infection and the mechanisms of immune evasion employed by the virus. It also discusses the challenges and opportunities for developing effective vaccines and therapeutics against this important animal disease.
Asunto(s)
Virus de la Fiebre Aftosa , Fiebre Aftosa , Evasión Inmune , Inmunidad Innata , Vacunas Virales , Animales , Fiebre Aftosa/inmunología , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/inmunología , Virus de la Fiebre Aftosa/patogenicidad , Vacunas Virales/inmunología , Inmunidad Adaptativa , Humanos , Interacciones Huésped-Patógeno/inmunología , Variación AntigénicaRESUMEN
Vaccination is a feasible approach for controlling foot-and-mouth disease (FMD). In FMD-free countries, vaccines are stored as a precautionary measure to control potential outbreaks. However, the challenge lies in pre-stocking optimal vaccines against the newly emerging strains. This study examined the potency of pre-stocked vaccines administered at elevated doses during emergencies. We vaccinated the cows with either a single or double trivalent vaccine dose containing two serotype O and one serotype A strains. Subsequently, vaccinated and unvaccinated cows were exposed to virulent strains of serotype O (O/JPN/2010; topotype Southeast Asia/Mya-98 lineage) or A (A/IRN/2016; topotype ASIA/G-VII lineage), which were genetically and antigenically distinct from the vaccine strains. Following challenge infections, all cows that received a single dose vaccination exhibited vesicular lesions with excreted viruses in the oral and nasal discharges. However, a substantial reduction was observed in the total clinical scores and virus titers in the sera and nasal discharges compared to those in the unvaccinated group. Cows receiving a doubled dose vaccination were completely protected from infection with O/JPN/2010 or demonstrated a significant decrease in viral shedding and clinical scores against A/IRN/2016. To note, vesicular lesions harbor significant amounts of viruses; thus, by mitigating their formation, viral transmission can be impeded, thereby slowing viral spread in the field. Furthermore, increasing the vaccine dose induced higher neutralizing antibody titers against heterologous strains. These findings suggest an alternative strategy for the effective management of future epidemics using pre-stocked vaccines.
Asunto(s)
Enfermedades de los Bovinos , Virus de la Fiebre Aftosa , Fiebre Aftosa , Vacunas Virales , Animales , Bovinos , Fiebre Aftosa/prevención & control , Fiebre Aftosa/inmunología , Fiebre Aftosa/virología , Vacunas Virales/inmunología , Vacunas Virales/administración & dosificación , Enfermedades de los Bovinos/prevención & control , Enfermedades de los Bovinos/virología , Enfermedades de los Bovinos/inmunología , Virus de la Fiebre Aftosa/inmunología , Femenino , Vacunación/veterinaria , Anticuerpos Antivirales/sangre , Esparcimiento de Virus , SerogrupoRESUMEN
BACKGROUND & AIMS: The spread of foot-and-mouth disease virus (FMDV) through aerosol droplets among cloven-hoofed ungulates in close contact is a major obstacle for successful animal husbandry. Therefore, the development of suitable mucosal vaccines, especially nasal vaccines, to block the virus at the initial site of infection is crucial. PATIENTS AND METHODS: Here, we constructed eukaryotic expression plasmids containing the T and B-cell epitopes (pTB) of FMDV in tandem with the molecular mucosal adjuvant Fms-like tyrosine kinase receptor 3 ligand (Flt3 ligand, FL) (pTB-FL). Then, the constructed plasmid was electrostatically attached to mannose-modified chitosan-coated poly(lactic-co-glycolic) acid (PLGA) nanospheres (MCS-PLGA-NPs) to obtain an active nasal vaccine targeting the mannose-receptor on the surface of antigen-presenting cells (APCs). RESULTS: The MCS-PLGA-NPs loaded with pTB-FL not only induced a local mucosal immune response, but also induced a systemic immune response in mice. More importantly, the nasal vaccine afforded an 80% protection rate against a highly virulent FMDV strain (AF72) when it was subcutaneously injected into the soles of the feet of guinea pigs. CONCLUSIONS: The nasal vaccine prepared in this study can effectively induce a cross-protective immune response against the challenge with FMDV of same serotype in animals and is promising as a potential FMDV vaccine.
Asunto(s)
Administración Intranasal , Quitosano , Virus de la Fiebre Aftosa , Fiebre Aftosa , Nanosferas , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Vacunas Virales , Animales , Quitosano/química , Quitosano/administración & dosificación , Virus de la Fiebre Aftosa/inmunología , Virus de la Fiebre Aftosa/genética , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Fiebre Aftosa/prevención & control , Fiebre Aftosa/inmunología , Ratones , Nanosferas/química , Vacunas Virales/inmunología , Vacunas Virales/administración & dosificación , Ratones Endogámicos BALB C , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Femenino , Ácidos Nucleicos/administración & dosificación , Inmunidad Mucosa , Sistemas de Liberación de MedicamentosRESUMEN
In Foot-and-mouth disease (FMD) enzootic countries, periodic vaccination is the key tool in controlling the disease incidence. Active seromonitoring of the vaccinated population is critical to assess the impact of vaccination. Virus neutralization test (VNT) and enzyme-linked immunosorbent assays (ELISA) are commonly used for antibody detection. Assays like liquid phase blocking ELISA (LPBE) or solid phase competition ELISA (SPCE) are preferred as they do not require handling of live FMDV and are routinely used for seromonitoring or for vaccine potency testing; however, false positives are high in LPBE. Here we report, a monoclonal antibody (mAb) based SPCE as a potential alternate assay for antibody titration. From a panel of 12 mAbs against FMDV serotype A, two mAbs were chosen for the development of SPCE. Based on a set of 453 sera, it was demonstrated that mAb 2C4G11, mAb 6E8D11and polyclonal antibody (pAb) based SPCE had a relative sensitivity of 86.1, 86.1 and 80.3â¯%; and specificity of 99.6, 99.1 and 99.1â¯%, respectively. The correlation, repeatability, and level of agreement of the assays were high demonstrating the potential use of mAb in large scale surveillance studies and regular vaccine potency testing.
Asunto(s)
Anticuerpos Monoclonales , Anticuerpos Antivirales , Ensayo de Inmunoadsorción Enzimática , Virus de la Fiebre Aftosa , Fiebre Aftosa , Sensibilidad y Especificidad , Serogrupo , Ensayo de Inmunoadsorción Enzimática/métodos , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Virus de la Fiebre Aftosa/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Fiebre Aftosa/diagnóstico , Fiebre Aftosa/inmunología , Fiebre Aftosa/virología , Bovinos , Pruebas de Neutralización/métodosRESUMEN
In order to develop a safe and effective broad-spectrum vaccine for foot-and-mouth disease (FMDV), here, we developed a recombinant FMD multiple-epitope trivalent vaccine based on three distinct topotypes of FMDV. Potency of the vaccine was evaluated by immune efficacy in pigs. The results showed that the vaccine with no less than 25 µg of antigen elicited FMDV serotype O specific antibodies and neutralization antibodies by primary-booster regime, and offered immune protection to pigs. More importantly, the vaccine elicited not only the same level of neutralization antibodies against the three distinct topotypes of FMDV, but also provided complete protection in pigs from the three corresponding virus challenge. None of the fully protected pigs were able to generate anti-3ABC antibodies throughout the experiment, which implied the vaccine can offer sterilizing immunity. The vaccine elicited lasting-long high-level antibodies and effectively protected pigs from virulent challenge within six months of immunization. Therefore, we consider that this vaccine may be used in the future for the prevention and control of FMD.
Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Epítopos , Virus de la Fiebre Aftosa , Fiebre Aftosa , Serogrupo , Enfermedades de los Porcinos , Vacunas Sintéticas , Vacunas Virales , Animales , Virus de la Fiebre Aftosa/inmunología , Virus de la Fiebre Aftosa/genética , Fiebre Aftosa/prevención & control , Fiebre Aftosa/inmunología , Fiebre Aftosa/virología , Porcinos , Vacunas Virales/inmunología , Vacunas Virales/genética , Vacunas Virales/administración & dosificación , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Enfermedades de los Porcinos/prevención & control , Enfermedades de los Porcinos/virología , Enfermedades de los Porcinos/inmunología , Epítopos/inmunología , Epítopos/genética , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Eficacia de las VacunasRESUMEN
Inactivated vaccines lack the capability to serologically differentiate between infected and vaccinated animals, thereby impeding the effective eradication of pathogen. Conversely, vaccines based on virus-like particles (VLPs) emulate natural viruses in both size and antigenic structure, presenting a promising alternative to overcome these limitations. As the complexity of swine infectious diseases increases, the increase of vaccine types and doses may intensify the stress response. This exacerbation can lead to diminished productivity, failure of immunization, and elevated costs. Given the critical dynamics of co-infection and the clinically indistinguishable symptoms associated with foot-and-mouth disease virus (FMDV) and senecavirus A (SVA), there is a dire need for an efficacious intervention. To address these challenges, we developed a combined vaccine composed of three distinct VLPs, specifically designed to target SVA and FMDV serotypes O and A. Our research demonstrates that this trivalent VLP vaccine induces antigen-specific and robust serum antibody responses, comparable to those produced by the respective monovalent vaccines. Moreover, the immune sera from the combined VLP vaccine strongly neutralized FMDV type A and O, and SVA, with neutralization titers comparable to those of the individual vaccines, indicating a high level of immunogenic compatibility among the three VLP components. Importantly, the combined VLPs vaccines-immunized sera conferred efficient protection against single or mixed infections with FMDV type A and O, and SVA viruses in pigs. In contrast, individual vaccines could only protect pigs against homologous virus infections and not against heterologous challenges. This study presents a novel combined vaccines candidate against FMD and SVA, and provides new insights for the development of combination vaccines for other viral swine diseases.
Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Virus de la Fiebre Aftosa , Fiebre Aftosa , Picornaviridae , Enfermedades de los Porcinos , Vacunas de Partículas Similares a Virus , Vacunas Virales , Animales , Vacunas de Partículas Similares a Virus/inmunología , Vacunas de Partículas Similares a Virus/administración & dosificación , Fiebre Aftosa/prevención & control , Fiebre Aftosa/inmunología , Virus de la Fiebre Aftosa/inmunología , Porcinos , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Vacunas Virales/inmunología , Vacunas Virales/administración & dosificación , Enfermedades de los Porcinos/prevención & control , Enfermedades de los Porcinos/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Ratones , Picornaviridae/inmunología , Infecciones por Picornaviridae/prevención & control , Infecciones por Picornaviridae/inmunología , Infecciones por Picornaviridae/veterinaria , Femenino , Vacunas Combinadas/inmunología , Vacunas Combinadas/administración & dosificación , Coinfección/prevención & control , Coinfección/inmunologíaRESUMEN
Southern Africa Territories 2 (SAT2) foot-and-mouth disease (FMD) has crossed long-standing regional boundaries in recent years and entered the Middle East. However, the existing vaccines offer poor cross-protection against the circulating strains in the field. Therefore, there is an urgent need for an alternative design approach for vaccines in anticipation of a pandemic of SAT2 Foot-and-mouth disease virus (FMDV). The porcine parvovirus (PPV) VP2 protein can embed exogenous epitopes into the four loops on its surface, assemble into virus-like particles (VLPs), and induce antibodies and cytokines to PPV and the exogenous epitope. In this study, chimeric porcine parvovirus VP2 VLPs (chimeric PPV-SAT2-VLPs) expressing the T-and/or B-cell epitopes of the structural protein VP1 of FMDV SAT2 were produced using the recombinant pFastBac™ Dual vector of baculoviruses in Sf9 and HF cells We used the Bac-to-Bac system to construct the recombinant baculoviruses. The VP2-VLP--SAT2 chimeras displayed chimeric T-cell epitope (amino acids 21-40 of VP1) and/or the B-cell epitope (amino acids 135-174) of SAT FMDV VP1 by substitution of the corresponding regions at the N terminus (amino acids 2-23) and/or loop 2 and/or loop 4 of the PPV VP2 protein, respectively. In mice, the chimeric PPV-SAT2-VLPs induced specific antibodies against PPV and the VP1 protein of SAT2 FMDV. The VP2-VLP-SAT2 chimeras induced specific antibodies to PPV and the VP1 protein specific epitopes of FMDV SAT2. In this study, as a proof-of-concept, successfully generated chimeric PPV-VP2 VLPs expressing epitopes of the structural protein VP1 of FMDV SAT2 that has a potential to prevent FMDV SAT2 and PPV infection in pigs.
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Anticuerpos Antivirales , Antígenos Virales , Proteínas de la Cápside , Virus de la Fiebre Aftosa , Fiebre Aftosa , Parvovirus Porcino , Vacunas de Partículas Similares a Virus , Vacunas Virales , Animales , Virus de la Fiebre Aftosa/inmunología , Virus de la Fiebre Aftosa/genética , Ratones , Fiebre Aftosa/inmunología , Fiebre Aftosa/prevención & control , Fiebre Aftosa/virología , Proteínas de la Cápside/inmunología , Proteínas de la Cápside/genética , Parvovirus Porcino/inmunología , Parvovirus Porcino/genética , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Vacunas Virales/inmunología , Vacunas Virales/genética , Vacunas de Partículas Similares a Virus/inmunología , Vacunas de Partículas Similares a Virus/genética , Porcinos , Inmunidad Humoral , Inmunidad Celular , Epítopos de Linfocito T/inmunología , Epítopos de Linfocito T/genética , Epítopos de Linfocito B/inmunología , Epítopos de Linfocito B/genética , Serogrupo , Ratones Endogámicos BALB C , Femenino , Epítopos/inmunología , Epítopos/genética , Células Sf9 , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangreRESUMEN
Foot-and-mouth disease virus (FMDV) remains a challenge for cloven-hooved animals. The currently licensed FMDV vaccines induce neutralizing antibody (NAb)-mediated protection but show defects in the early protection. Dendritic cell (DC) vaccines have shown great potency in inducing rapid T-cell immunity in humans and mice. Whether DC vaccination could enhance early protection against FMDV has not been elaborately explored in domestic pigs. In this study, we employed DC vaccination as an experimental approach to study the roles of cellular immunity in the early protection against FMDV in pigs. Autologous DCs were differentiated from the periphery blood mononuclear cells of each pig, pulsed with inactivated FMDV (iFMDV-DC) and treated with LPS, and then injected into the original pigs. The cellular immune responses and protective efficacy elicited by the iFMDV-DC were examined by multicolor flow cytometry and tested by FMDV challenge. The results showed that autologous iFMDV-DC immunization induced predominantly FMDV-specific IFN-γ-producing CD4+ T cells and cytotoxic CD8+ T cells (CTLs), high NAb titers, compared to the inactivated FMDV vaccine, and accelerated the development of memory CD4 and CD8 T cells, which was concomitantly associated with early protection against FMDV virulent strain in pigs. Such early protection was associated with the rapid proliferation of secondary T-cell response after challenge and significantly contributed by secondary CD8 effector memory T cells. These results demonstrated that rapid induction of cellular immunity through DC immunization is important for improving early protection against FMDV. Enhancing cytotoxic CD8+ T cells may facilitate the development of more effective FMDV vaccines.IMPORTANCEAlthough the currently licensed FMDV vaccines provide NAb-mediated protection, they have defects in early immune protection, especially in pigs. In this study, we demonstrated that autologous swine DC immunization augmented the cellular immune response and induced an early protective response against FMDV in pigs. This approach induced predominantly FMDV-specific IFN-γ-producing CD4+ T cells and cytotoxic CD8+ T cells, high NAb titers, and rapid development of memory CD4 and CD8 T cells. Importantly, the early protection conferred by this DC immunization is more associated with secondary CD8+ T response rather than NAbs. Our findings highlighted the importance of enhancing cytotoxic CD8+ T cells in early protection to FMDV in addition to Th1 response and identifying a strategy or adjuvant comparable to the DC vaccine might be a future direction for improving the current FMDV vaccines.
Asunto(s)
Virus de la Fiebre Aftosa , Fiebre Aftosa , Vacunas Virales , Animales , Humanos , Ratones , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Linfocitos T CD8-positivos , Fiebre Aftosa/inmunología , Fiebre Aftosa/prevención & control , Virus de la Fiebre Aftosa/fisiología , Porcinos , VacunaciónRESUMEN
Foot-and-mouth disease (FMD) has a high prevalence in cloven-hoofed animals. It is also highly contagious and remains a serious threat to livestock worldwide. Despite the widespread vaccination program in Iran, outbreaks of FMD continue to occur. Vaccination is one of the most effective methods of preventing FMD. The vaccines used in Iran are of the inactivated type and contain several serotypes. Since inactivated vaccines without adjuvants do not induce a high and durable antibody response, it is necessary to use adjuvants. Montanide ISA 206 VG is a mineral oil-based adjuvant that produces a water-in-oil-in-water (w:o:w) emulsion in vaccine preparations. However, a large number of manufacturers in Iran and around the world still use alum adjuvant (with or without saponin) to produce the FMD vaccine. This study used Montanide ISA 206 and alum adjuvants to administer the O2010 serotype of the FMD virus to goats. A total of six goats were divided randomly into three groups. Vaccines were administered subcutaneously twice, at a one-month interval. Blood sampling was done at different times, and the micro-neutralization method was used to measure the neutralizing antibody titer in each serum. Seven days after the second vaccination, the alum group's antibody titer was higher but not statistically significant. However, from the 28th day after the second injection until the end of the study, the Montanide ISA 206 group's antibody titer was significantly higher than that of the alum group. Six months after the second injection, the antibody titer in the ISA 206 group remained at the peak level, while in the alum group, it decreased and reached the minimum protective level. Nine months after the second injection, the antibody titer remained at its peak level in the ISA 206 group, whereas it dropped significantly in the alum group. Based on the findings, ISA 206 VG is capable of generating long-term humoral immunity in goats against the FMD serotype O2010 and could replace aluminum hydroxide adjuvants in FMD vaccine preparations.
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Adyuvantes Inmunológicos , Hidróxido de Aluminio , Anticuerpos Neutralizantes , Virus de la Fiebre Aftosa , Fiebre Aftosa , Enfermedades de las Cabras , Cabras , Vacunas Virales , Animales , Hidróxido de Aluminio/administración & dosificación , Hidróxido de Aluminio/farmacología , Virus de la Fiebre Aftosa/inmunología , Enfermedades de las Cabras/prevención & control , Fiebre Aftosa/prevención & control , Fiebre Aftosa/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Adyuvantes Inmunológicos/farmacología , Vacunas Virales/inmunología , Vacunas Virales/administración & dosificación , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Irán , Ácidos Oléicos/administración & dosificación , Manitol/análogos & derivados , Manitol/administración & dosificaciónRESUMEN
Foot-and-mouth disease (FMD) is an acute contagious disease that affects cloven-hoofed animals and has severe global economic consequences. FMD is most commonly controlled by vaccination. Currently available commercial FMD vaccines contain chemically inactivated whole viruses, which are thought to be slow acting as they are effective only 4 to 7 days following vaccination. Hence, the development of a novel rapid vaccine or alternative measures, such as antiviral agents or the combination of vaccines and antiviral agents for prompt FMD virus (FMDV) outbreak containment, is desirable. Here, we constructed a recombinant baculovirus (BacMam) expressing consensus porcine interferon alpha (IFN-α) that has three additional N-glycosylation sites driven by a cytomegalovirus immediate early (CMV-IE) promoter (Bac-Con3N IFN-α) for protein expression in mammalian cells. Bac-Con3N IFN-α expressing highly glycosylated porcine IFN-α protein increased the duration of antiviral effects. We evaluated the antiviral effects of Bac-Con3N IFN-α in swine cells and mice and observed sustained antiviral effects in pig serum; additionally, Bac-Con3N IFN-α exhibited sustained antiviral effects in vivo as well as adjuvant effects in combination with an inactivated FMD vaccine. Pigs injected with a combination of Bac-Con3N IFN-α and the inactivated FMD vaccine were protected against FMDV at 1, 3, and 7 days postvaccination. Furthermore, we observed that in combination with the inactivated FMD vaccine, Bac-Con3N IFN-α increased neutralizing antibody levels in mice and pigs. Therefore, we suggest that Bac-Con3N IFN-α is a strong potential antiviral and adjuvant candidate for use in combination with inactivated FMD vaccines to protect pigs against FMDV. IMPORTANCE Early inhibition of foot-and-mouth disease (FMD) virus (FMDV) replication in pigs is highly desirable as FMDV transmission and shedding rates are higher in pigs than in cattle. However, commercial FMD vaccines require at least 4 to 7 days postvaccination (dpv) for protection, and animals are vulnerable to heterologous viruses before acquiring high antibody levels after the second vaccination. Therefore, the development of antiviral agents for use in combination with FMD vaccines is essential. We developed a novel antiviral and immunostimulant, Bac-Con3N IFN-α, which is a modified porcine IFN-α-expressing recombinant baculovirus, to improve IFN stability and allow its direct delivery to animals. We present a promising candidate for use in combination with inactivated FMD vaccines as pigs applied to the strategy had early protection against FMDV at 1 to 7 dpv, and their neutralizing antibody levels were higher than those in pigs administered the vaccine only.
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Virus de la Fiebre Aftosa , Fiebre Aftosa , Interferón-alfa , Vacunas Virales , Adyuvantes Inmunológicos/farmacología , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Antivirales/farmacología , Baculoviridae , Fiebre Aftosa/inmunología , Fiebre Aftosa/prevención & control , Interferón-alfa/farmacología , Ratones , Porcinos , Vacunas de Productos InactivadosRESUMEN
The recent emergence and circulation of the A/ASIA/G-VII (A/G-VII) lineage of foot-and-mouth disease virus (FMDV) in the Middle East has resulted in the development of homologous vaccines to ensure susceptible animals are sufficiently protected against clinical disease. However, a second serotype A lineage called A/ASIA/Iran-05 (A/IRN/05) continues to circulate in the region and it is therefore imperative to ensure vaccine strains used will protect against both lineages. In addition, for FMDV vaccine banks that usually hold a limited number of strains, it is necessary to include strains with a broad antigenic coverage. To assess the cross protective ability of an A/G-VII emergency vaccine (formulated at 43 (95% CI 8-230) PD50/dose as determined during homologous challenge), we performed a heterologous potency test according to the European Pharmacopoeia design using a field isolate from the A/IRN/05 lineage as the challenge virus. The estimated heterologous potency in this study was 2.0 (95% CI 0.4-6.0) PD50/dose, which is below the minimum potency recommended by the World Organisation for Animal Health (OIE). Furthermore, the cross-reactive antibody titres against the heterologous challenge virus were poor (≤log10 0.9), even in those cattle that had received the full dose of vaccine. The geometric mean r1-value was 0.2 (95% CI 0.03-0.8), similar to the potency ratio of 0.04 (95% CI 0.004-0.3). Vaccination decreased viraemia and virus excretion compared to the unvaccinated controls. Our results indicate that this A/G-VII vaccine does not provide sufficient protection against viruses belonging to the A/IRN/05 lineage and therefore the A/G-VII vaccine strain cannot replace the A/IRN/05 vaccine strain but could be considered an additional strain for use in vaccines and antigen banks.
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Enfermedades de los Bovinos/prevención & control , Virus de la Fiebre Aftosa/inmunología , Fiebre Aftosa/prevención & control , Inmunidad Heteróloga , Vacunas Virales/inmunología , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/virología , Protección Cruzada , Fiebre Aftosa/inmunología , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/genética , Virus de la Fiebre Aftosa/aislamiento & purificación , ARN Viral/análisis , Serogrupo , Potencia de la Vacuna , Viremia/prevención & control , Viremia/veterinaria , Esparcimiento de VirusRESUMEN
Foot and mouth disease virus (FMDV), whose transmission occurs through mucosal surfaces, can also be transmitted through aerosols, direct contact, and pollutants. Therefore, mucosal immunity can efficiently inhibit viral colonization. Since vaccine material delivery into immune sites is important for efficient oral mucosal vaccination, the M cell-targeting approach is important for effective vaccination given M cells are vital for luminal antigen influx into the mucosal lymph tissues. In this study, we coupled M cell-targeting ligand Co1 to multi-epitope TB1 of FMDV to obtain TB1-Co1 in order to improve delivery efficiency of the multi-epitope protein antigen TB1. Lactococcus lactis (L. lactis) was engineered to express heterologous antigens for applications as vaccine vehicles with the ability to elicit mucosal as well as systemic immune responses. We successfully constructed L. lactis (recombinant) with the ability to express multi-epitope antigen proteins (TB1 and TB1-Co1) of the FMDV serotype A (named L. lactis-TB1 and L. lactis-TB1-Co1). Then, we investigated the immunogenic potential of the constructed recombinant L. lactis in mice and guinea pigs. Orally administered L. lactis-TB1 as well as L. lactis-TB1-Co1 in mice effectively induced mucosal secretory IgA (SIgA) and IgG secretion, development of a strong cell-mediated immune reactions, substantial T lymphocyte proliferation in the spleen, and upregulated IL-2, IFN-γ, IL-10, and IL-5 levels. Orally administered ligand-conjugated TB1 promoted specific IgG as well as SIgA responses in systemic and mucosal surfaces, respectively, when compared to orally administered TB1 alone. Then, guinea pigs were orally vaccinated with L. lactis-TB1-Co1 plus adjuvant CpG-ODN at three different doses, L. lactis-TB1-Co1, and PBS. Animals that had been immunized with L. lactis-TB1-Co1 plus adjuvant CpG-ODN and L. lactis-TB1-Co1 developed elevated antigen-specific serum IgG, IgA, neutralizing antibody, and mucosal SIgA levels, when compared to control groups. Particularly, in mice, L. lactis-TB1-Co1 exhibited excellent immune effects than L. lactis-TB1. Therefore, L. lactis-TB1-Co1 can induce elevations in mucosal as well as systemic immune reactions, and to a certain extent, provide protection against FMDV. In conclusion, M cell-targeting approaches can be employed in the development of effective oral mucosa vaccines for FMDV.
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Epítopos/inmunología , Virus de la Fiebre Aftosa/metabolismo , Fiebre Aftosa/inmunología , Lactococcus lactis/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Animales , Anticuerpos Neutralizantes , Anticuerpos Antivirales/sangre , Formación de Anticuerpos , Modelos Animales de Enfermedad , Femenino , Virus de la Fiebre Aftosa/genética , Cobayas , Inmunidad Mucosa/inmunología , Inmunización , Inmunoglobulina A Secretora , Lactococcus lactis/genética , Activación de Linfocitos , Ratones , Ratones Endogámicos BALB C , Proteínas Recombinantes , Vacunación , Vacunas Virales/inmunologíaRESUMEN
As a structural protein of the Foot-and-mouth disease virus (FMDV), VP3 plays a vital role in virus assembly and inhibiting the interferon (IFN) signal transduction to promote FMDV replication. Previous studies demonstrated that FMDV VP3 blocks the type-I IFN response by inhibiting the mRNA expression of the mitochondrial antiviral-signaling protein (MAVS); however, the underlying mechanism is poorly understood. Here, we describe the specificity of FMDV VP3 interaction with the transmembrane (TM) domain of MAVS as FMDV driven type-I IFN inhibitory mechanism for its effective replication. The TM domain of MAVS governs the mitochondria localization of MAVS, and it is a key factor in type-I IFN signaling transduction via MAVS aggregation. Thereby, the interaction of FMDV VP3 with the TM domain of MAVS leads to the inhibition of MAVS mitochondria localization, self-association, and aggregation, resulting in the suppression of type-I IFN response. Collectively, these results provide a clear understanding of a key molecular mechanism used by the FMDV VP3 for the suppression of IFN responses via targeting MAVS.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Virus de la Fiebre Aftosa , Fiebre Aftosa/inmunología , Interferón Tipo I/metabolismo , Animales , Anticuerpos Antivirales , Fiebre Aftosa/virología , Virus de la Fiebre Aftosa/genética , Células HEK293 , Células HeLa , Interacciones Huésped-Patógeno/inmunología , Humanos , Ratones , Mitocondrias/metabolismo , Células RAW 264.7 , ARN Mensajero/metabolismo , Transducción de Señal/fisiologíaRESUMEN
As one of the most infectious livestock diseases in the world, foot and mouth disease (FMD) presents a constant global threat to animal trade and national economies. FMD remains a severe constraint on development and poverty reduction throughout the developing world due to many reasons, including the cost of control measures, closure of access to valuable global FMD-free markets for livestock products, production losses through reduced milk yield, reduced live weight gain, and the inability of infected livestock to perform traction. FMD virus infects a variety of cloven-hoofed animals, including cattle, sheep, goats, swine, all wild ruminants, and suidae, with high morbidity in adult animals. High mortality can occur in young animals due to myocarditis. FMD is endemic in Africa, most of Asia, the Middle East, and parts of South America. The global clustering of FMD viruses has been divided into seven virus pools, where multiple serotypes occur but within which are topotypes that remain mostly confined to that pool. Three pools cover Europe, the Middle East, and Asia; three pools cover Africa; and one pool covers the Americas. The highly infectious nature of FMDV, the existence of numerous continually circulating serotypes and associated topotypes, the potential for wildlife reservoirs, and the frequent emergence of new strains that are poorly matched to existing vaccines all serve to compound the difficulties faced by the governments of endemic countries to effectively control and reduce the burden of the disease at the national and regional levels. This clustering of viruses suggests that if vaccination is to be a major tool for control, each pool could benefit from the use of tailored or more specific vaccines relevant to the topotypes present in that pool, rather than a continued reliance on the currently more widely available vaccines. It should also be noted that, currently, there are varying degrees of effort to identify improved vaccines in different regions. There are relatively few targeted for use in Africa, while the developed world's vaccine banks have a good stock of vaccines destined for emergency outbreak use in FMDV-free countries. The AgResults Foot and Mouth Disease (FMD) Vaccine Challenge Project (the "Project") is an eight-year, US $17.68 million prize competition that supports the development and uptake of high-quality quadrivalent FMD vaccines tailored to meet the needs of Eastern Africa (EA). The Project targets the following Pool Four countries: Burundi, Ethiopia, Kenya, Rwanda, Tanzania and Uganda. The Project is being run in two phases: a development phase, which will encourage the production of regionally relevant vaccines, and a cost-share phase, designed to help to reduce the price of these vaccines in the marketplace to the end users, which is hoped will encourage broader uptake. Manufacturers can submit quadrivalent FMD vaccines containing serotypes A, O, SAT1, and SAT2, which will be assessed as relevant for use in the region through a unique component of the Project requiring the screening of vaccines against the Eastern Africa Foot and Mouth Disease Virus Reference Antigen Panel assembled by the World Reference Laboratory for FMD (WRLFMD), at the Pirbright Institute, UK, in collaboration with the OIE/FAO FMD Reference Laboratory Network. To be eligible for the Project, sera from vaccinated cattle will be used to evaluate serological responses of FMD vaccines for their suitability for use in Eastern African countries. If they pass a determined cut-off threshold, they will be confirmed as relevant for use in the region and will be entered into the Project's cost-share phase.
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Virus de la Fiebre Aftosa/inmunología , Fiebre Aftosa/inmunología , Programas de Inmunización , Desarrollo de Vacunas , Vacunas Virales/inmunología , África Oriental , Animales , Fiebre Aftosa/prevención & control , Programas de Inmunización/economía , Asociación entre el Sector Público-Privado , Control de Calidad , Vacunas Virales/normasRESUMEN
Foot-and-mouth disease virus (FMDV) exhibits broad antigenic diversity with poor intraserotype cross-neutralizing activity. Studies of the determinant involved in this diversity are essential for the development of broadly protective vaccines. In this work, we isolated a bovine antibody, designated R55, that displays cross-reaction with both FMDV A/AF/72 (hereafter named FMDV-AAF) and FMDV A/WH/09 (hereafter named FMDV-AWH) but only has a neutralizing effect on FMDV-AWH. Near-atomic resolution structures of FMDV-AAF-R55 and FMDV-AWH-R55 show that R55 engages the capsids of both FMDV-AAF and FMDV-AWH near the icosahedral 3-fold axis and binds to the ßB and BC/HI-loops of VP2 and to the B-B knob of VP3. The common interaction residues are highly conserved, which is the major determinant for cross-reaction with both FMDV-AAF and FMDV-AWH. In addition, the cryo-EM structure of the FMDV-AWH-R55 complex also shows that R55 binds to VP3E70 located at the VP3 BC-loop in an adjacent pentamer, which enhances the acid and thermal stabilities of the viral capsid. This may prevent capsid dissociation and genome release into host cells, eventually leading to neutralization of the viral infection. In contrast, R55 binds only to the FMDV-AAF capsid within one pentamer due to the VP3E70G variation, which neither enhances capsid stability nor neutralizes FMDV-AAF infection. The VP3E70G mutation is the major determinant involved in the neutralizing differences between FMDV-AWH and FMDV-AAF. The crucial amino acid VP3E70 is a key component of the neutralizing epitopes, which may aid in the development of broadly protective vaccines. IMPORTANCE Foot-and-mouth disease virus (FMDV) causes a highly contagious and economically devastating disease in cloven-hoofed animals, and neutralizing antibodies play critical roles in the defense against viral infections. Here, we isolated a bovine antibody (R55) using the single B cell antibody isolation technique. Enzyme-linked immunosorbent assays (ELISA) and virus neutralization tests (VNT) showed that R55 displays cross-reactions with both FMDV-AWH and FMDV-AAF but only has a neutralizing effect on FMDV-AWH. Cryo-EM structures, fluorescence-based thermal stability assays and acid stability assays showed that R55 engages the capsid of FMDV-AWH near the icosahedral 3-fold axis and informs an interpentamer epitope, which overstabilizes virions to hinder capsid dissociation to release the genome, eventually leading to neutralization of viral infection. The crucial amino acid VP3E70 forms a key component of neutralizing epitopes, and the determination of the VP3E70G mutation involved in the neutralizing differences between FMDV-AWH and FMDV-AAF could aid in the development of broadly protective vaccines.