FMDV Vaccine Research Articles

Development of swine Fc-conjugated serotype O foot-and-mouth disease virus-like particles and immunological evaluation in swine

Abstract The outbreak of foot-and-mouth disease (FMD) has been declining as a result of efforts by many advanced countries to eradicate it. However, new vaccine types are being developed because FMD is still a problem in several countries, and vaccinations have safety concerns. In this study, we developed a new FMD vaccine using virus-like particles (VLPs) harboring the immunoglobulin G Fc molecule on their surface. Based on the results of vaccination studies in swine, we confirmed its high efficacy. In particular, we confirmed strong immune boosting by the addition of the swine IgG (sFc) region. The FMDV VLP-sFc vaccine produced higher amounts of Th1 cytokines (IFN-γ, IL-12, and TNF) and Th2 cytokines (IL-4) than the commercial vaccine. More importantly, FMDV VLP-sFc induced significantly higher levels of neutralizing antibodies. Taken together, our newly developed FMDV vaccine, FMDV VLP-sFc, may be a great new and effective FMDV vaccine.

A meta-analysis on the potency of foot-and-mouth disease vaccines in different animal models.

Whether mice can be used as a foot-and-mouth disease (FMD) model has been debated for a long time. However, the major histocompatibility complex between pigs and mice is very different. In this study, the protective effects of FMD vaccines in different animal models were analyzed by a meta-analysis. The databases PubMed, China Knowledge Infrastructure, EMBASE, and Baidu Academic were searched. For this purpose, we evaluated evidence from 14 studies that included 869 animals with FMD vaccines. A random effects model was used to combine effects using Review Manager 5.4 software. A forest plot showed that the protective effects in pigs were statistically non-significant from those in mice [MH = 0.56, 90% CI (0.20, 1.53), P = 0.26]. The protective effects in pigs were also statistically non-significant from those in guinea pigs [MH = 0.67, 95% CI (0.37, 1.21), P = 0.18] and suckling mice [MH = 1.70, 95% CI (0.10, 28.08), P = 0.71]. Non-inferiority test could provide a hypothesis that the models (mice, suckling mice and guinea pigs) could replace pigs as FMDV vaccine models to test the protective effect of the vaccine. Strict standard procedures should be established to promote the assumption that mice and guinea pigs should replace pigs in vaccine evaluation.

Development and efficacy evaluation of a novel water-in-oil-in-water adjuvant for an inactivated foot-and-mouth disease vaccine

ABSTRACT To develop a novel water-in-oil-in-water (W/O/W) adjuvant and evaluate the effect on foot-and-mouth disease (FMD) inactivated vaccine, in this study, we prepared the novel nano-emulsion adjuvant based on QS-21 (BEA) which is composed of the mixture of mineral oil Marcol52, surfactant Tween80, oleate polyoxyethylene ether ester, polyoxyethylene palmitic acid ester and span80, cosurfactant polyethylene glycol and QS-21. The two-step emulsification method formed the W/O/W nano-emulsion with two films and three-phase structures. The effective particle diameter of the BEA was about 184 nm, and it has good thermal stability. Then, BEA was emulsified as an adjuvant to prepare for the inactivated FMDV vaccine, and BALB/c mice and pigs were immunized to evaluate its safety and immunization effect. The results showed that the inactivated BEA-FMDV vaccine significantly increased BALB/c mice and pigs' antibodies and cytokine IFN-γ in serum. Meanwhile, the pig-neutralizing antibodies were higher than control group. Safety tests found no symptoms of FMD or significant toxic reactions. After 28 days of immunization, the protection rate can reach 93.3%. The BEA vaccine had good stability at 4 °C, no stratification after 180 days, and the content of 146S in the vaccine did not decrease. In conclusion, the BEA prepared in this study is suitable for FMDV inactivated vaccine and is an effective adjuvant.

Antiviral agents and disinfectants for foot‑and‑mouth disease (Review).

Fluorouracil, 5-azacytidine, 6-azauridine, ribavirin, favipiravir (T-705) and its derivative (T-1105) exhibit anti-foot-and-mouth disease virus (FMDV) effects. In particular, T-1105 exhibits promising results when administered to guinea pigs orally, and pigs in their feed. FMDV is excreted in the early stages of infection in aerosols and oral or nasal droplets from animals. T-1105 along with the FMDV vaccine can be used to combat foot-and-mouth disease (FMD) epidemics. Several studies have shown that sodium hypochlorous solutions are widely used to inactivate viruses, including FMDV. However, these solutions must be stored under cool and dark conditions to maintain their virucidal effects. Interestingly, a study indicated that the virucidal activity of a calcium bicarbonate solution with a mesoscopic structure (CAC-717) did not decrease after storage at room temperature for at least four years outside direct sunlight. Numerous lessons acquired from the 2010 FMD outbreak in Japan are relevant for the control of COVID-19. However, the widespread use of chlorite can cause environmental issues. Chlorite can be combined with nitrogen to produce chloramine or N-nitrosodimethylamine, which plays a role in carcinogenesis. Therefore, risk assessments should be conducted in aquatic environments. Moreover, there is a need to develop nonchlorine disinfectants that can be used during epidemics, including FMD. The approach of 'One Health' should be shared between the public health and veterinary fields to improve the management of viral outbreaks, including those due to FMD.

Immunogenicity analysis of the E. coli expressed structural protein VP1 of persistent infection foot-and-mouth disease virus

The persistent infection of FMDV in cloven hoofed animals has made the epidemic prevention and control more difficult. VP1 is the main immunogenic protein and first candidate of vaccine development for FMDV prevention. However, the mutation of VP1 in host cell with persistent infection FMDV (PI-FMDV) caused the change of its immunogenicity. Hence, it is imperative to establish the expression system for VP1 of PI-FMDV (PI-VP1) and re-evaluate its immunogenicity. In this study, the PI-VP1 with His-tag was cloned into pET-28a vector. PI-VP1 protein was expressed and purified in E. coli, and further the antiserum of immunized mice was analyzed. Results showed that purified PI-VP1 protein produced a good humoral and cellular immune response after immunizing mice. Furthermore, our study showed that the antiserum could not only neutralize PI-FMDV, but also prevent the adsorption of WT-FMDV. In summarize, our work provides valuable implications for the FMDV vaccines and therapeutics development.

Whole-genome sequencing of foot-and-mouth disease virus serotype O/PanAsia-2/QOM-15 and comparison of its VP1-encoding region with two vaccine strains.

Despite widespread vaccination against foot-and-mouth disease, many outbreaks still occur in endemic areas. We attempted to determine the genetic and antigenic properties of the O/PanAsia-2/QOM-15 foot-and-mouth disease virus new vaccine strain. Thus, whole-genome sequencing was used to identify vulnerable pinpoint sites across the genome. The VP1 sequence (1D gene) of the O/PanAsia-2/QOM-15 viral genome was then compared to the VP1 sequences of two previously used vaccine strains, O/PanAsia (JQ321837) and O/PanAsia-2 (JN676146). The antigenic relationship of these three viruses was calculated by the two dimensional-virus neutralization test. At the nucleotide level, 47 single variants were identified, of which 19.00% were in the 5' untranslated region (UTR), 79.00% in the polyprotein region, and 2.00% in the 3' UTR region. Approximately half of the single nucleotide polymorphisms that have occurred in 1D gene resulted in amino acid (AA) substitutions in the VP1 structure. The single nucleotide polymorphisms also caused AA substitutions in other structural proteins, including VP2 and VP3, and some non-structural proteins (Lpro, 2C, and 3A). The O/PanAsia-2/QOM-15 shared higher sequence similarity with O/PanAsia-2 (91.00%) compared to O/PanAsia (87.30%). Evaluating r-value showed that the antigenic relationship of O/PanAsia-2/QOM-15 with O/PanAsia-2 (29.00%) was greater than that of the O/PanAsia (24.00%); however, all three viruses were immunologically distinct. After 10 years, the alteration of virus antigenicity and the lack of detectable adaptive pressure on VP1 sequence suggest that studying genetic dynamics beyond the VP1 region is necessary to evaluate FMDV pathogenicity and vaccine failure.

Expression of FMD virus-like particles in yeast Hansenula polymorpha and immunogenicity of combine with CpG and aluminum adjuvant

Inactivated vaccines are limited in preventing foot-and-mouth disease (FMD) due to safety problems. Recombinant virus-like particles (VLPs) are an excellent candidate for a novel vaccine for preventing FMD, given that VLPs have similar immunogenicity as natural viruses and are replication- and infection-incompetent. The 3C protease and P1 polyprotein of type O FMD virus (FDMV) was expressed in yeast Hansenula polymorpha to generate self-resembling VLPs, and the potential of recombinant VLPs as an FMD vaccine was evaluated. BALB/c mice were immunized with recombinant purified VLPs using CpG oligodeoxynucleotide and aluminum hydroxide gel as an adjuvant. Cytokines and lymphocytes from serum and spleen were analyzed by enzyme-linked immunosorbent assay, enzyme-linked immunospot assay, and flow cytometry. The VLPs of FMD were purified successfully from yeast protein with a diameter of approximately 25 nm. The immunization of mice showed that animals produced high levels of FMDV antibodies and a higher level of antibodies for a longer time. In addition, higher levels of interferon-γ and CD4+ T cells were observed in mice immunized with VLPs. The expression of VLPs of FMD in H. polymorpha provides a novel strategy for the generation of the FMDV vaccine.

Computational analysis of proteome of Foot-and-mouth disease Virus for the prediction of immunogenic epitopes

ObjectiveFoot and Mouth Disease virus (FMDV) commonly affects cloven hoofed animals. Infection with one serotype does not confer immunity to others and currently available vaccines do not provide effective T-cell immunity. The objective of this work is to predict the Cytotoxic T lymphocyte (CTL) epitopes which could be used as vaccine components against FMD virus. Material and methodsProteomes of three Indian FMDV vaccine strains, Type A IND40/00, Type A IND17/82 and Asia-1 IND63/72 were retrieved. BoLa-T2b allele restricted CTL epitopes were predicted using Immune Epitope Data Base Analysis Resource (IEDB-AR) and NetMHCpan 2.8 tool. The predicted overlapping epitopes were further analysed for antigenicity prediction, binding to other BoLA allele and consensus epitope analysis. ResultsA total of 207 epitopes were predicted by IEDB-AR tool. Among this, 72, 68, 67, epitopes were predicted in Asia 1 IND 63/72, Type A IND40/00 and Type A IND17/82 respectively. Totally 489 epitopes were predicted by NetMHCpan 2.0 tool. Of which, 164, 163 and 162 epitopes were predicted in Type A IND17/82, Asia 1 IND63/72 and Type A IND40/00 respectively. In total 29 consensus epitopes were predicted during this analysis, among this, 28 epitopes are present to occur in all the three Indian strains that were tested. ConclusionsThe 29 consensus epitopes predicted in this study could be used for developing a potent vaccine for both Asia I and Type A strains of FMD. Further in vitro and in vivo studies are needed to confirm the CTL efficacy of this peptide against FMDV.

Development of swine Fc conjugated Serotype O Foot and mouth disease virus like particles

Abstract Foot-and mouth disease virus (FMDV) cause a highly contagious infection in cloven-hoofed animals. The current conventional FMD vaccines are produced by chemical inactivated virulent FMDV virions, but conventional FMD vaccines risky and limitation such as respect to accidental release of FMDV and high-level biosafety facilities were required to handle FDMV. FMDV virus like particle (VLP) could be alternative choice for future vaccine against FMDV because of efficacy and safety. Receptor for Fc portion of antibody play and important role in the activation of immune response for infection of virus and bacteria. Therefore, immunization with a complex of virus antigen and Fc has the potential to be an improved. Here we report our vaccine studies with Fc conjugated serotype O FMDV VLP for alternative FMDV vaccine.

Computational analysis of proteome of Foot-and-mouth disease Virus for the prediction of immunogenic epitopes

ObjectiveFoot and Mouth Disease virus (FMDV) commonly affects cloven hoofed animals. Infection with one serotype does not confer immunity to others and currently available vaccines do not provide effective T-cell immunity. The objective of this work is to predict the Cytotoxic T lymphocyte (CTL) epitopes which could be used as vaccine components against FMD virus. Material and methodsProteomes of three Indian FMDV vaccine strains, Type A IND40/00, Type A IND17/82 and Asia-1 IND63/72 were retrieved. BoLa-T2b allele restricted CTL epitopes were predicted using Immune Epitope Data Base Analysis Resource (IEDB-AR) and NetMHCpan 2.8 tool. The predicted overlapping epitopes were further analysed for antigenicity prediction, binding to other BoLA allele and consensus epitope analysis. ResultsA total of 207 epitopes were predicted by IEDB-AR tool. Among this, 72, 68, 67, epitopes were predicted in Asia 1 IND 63/72, Type A IND40/00 and Type A IND17/82 respectively. Totally 489 epitopes were predicted by NetMHCpan 2.0 tool. Of which, 164, 163 and 162 epitopes were predicted in Type A IND17/82, Asia 1 IND63/72 and Type A IND40/00 respectively. In total 29 consensus epitopes were predicted during this analysis, among this, 28 epitopes are present to occur in all the three Indian strains that were tested. ConclusionsThe 29 consensus epitopes predicted in this study could be used for developing a potent vaccine for both Asia I and Type A strains of FMD. Further in vitro and in vivo studies are needed to confirm the CTL efficacy of this peptide against FMDV.

Effect of Foot-and-Mouth Disease Vaccination on Acute Phase Immune Response and Anovulation in Hanwoo (Bos taurus coreanae).

Vaccination against foot-and-mouth disease is the most common method for preventing the spread of the disease; the negative effects include miscarriage, early embryo death, lower milk production, and decreased growth of fattening cattle. Therefore, in this study, we analyze the side effects of vaccination by determining the acute immune response and ovulation rate after vaccinating cows for foot-and-mouth disease. The test axis was synchronized with ovulation using 100 Hanwoo (Bos taurus coreanae) cows from the Gyeongsangbuk-do Livestock Research Institute; only individuals with estrus confirmed by ovarian ultrasound were used for the test. All test axes were artificially inseminated 21 days after the previous estrus date. The control group was administered 0.9% normal saline, the negative control was injected intramuscularly with lipopolysaccharide (LPS; 0.5 µg/kg), and the test group was administered a foot-and-mouth disease virus vaccine (FMDV vaccine; bioaftogen, O and A serotypes, inactivated vaccine) 2, 9, and 16 days before artificial insemination. White blood cells and neutrophils increased significantly 1 day after vaccination, and body temperature in the rumen increased for 16 h after vaccination. Ovulation was detected 1 day after artificial fertilization by ovarian ultrasound. The ovulation rates were as follows: control 89%, LPS 60%, FMDV vaccine (−2 d) 50%, FMDV vaccine (−9 d) 75%, and FMDV vaccine (−16 d) 75%. In particular, the FMDV vaccine (−2 d) test group confirmed that ovulation was delayed for 4 days after artificial insemination. In addition, it was confirmed that it took 9 days after inoculation for the plasma contents of haptoglobin and serum amyloid A to recover to the normal range as the main acute immune response factors. The conception rate of the FMDV vaccine (−2 d) group was 20%, which was significantly lower than that of the other test groups.

Layered double hydroxide nanoparticles as an adjuvant for inactivated foot-and-mouth disease vaccine in pigs

BackgroundFoot-and-mouth disease (FMD) is a highly transmissible disease that leads to vast economic losses in many countries. Prevention using inactivated vaccines is one effective measure used to control FMD. Unfortunately, inactivated FMD vaccines provide only short-term protection and require a cold-chain system. In recent years, many studies have shown that layered double metal hydroxides (LDHs) carrying antigens can be used to strongly induce immune responses. In this study, LDH nanoparticles (NPs) were prepared by hydrothermal synthesis. LDH particle size, electric potential, and morphology were measured and observed. The adsorption capacity of LDH NPs to FMDV was tested. The effects of LDH as an adjuvant on inactivated FMDV vaccines were further evaluated and compared with commercial FMDV Montanide ISA-206 in BALB/C female mice and Yorkshire pigs.ResultsLDH NPs were successfully prepared with a uniform particle size of ~ 87.21 nm, regular edges, a loose hexagonal shape and positive zeta charge of 32 mV. The maximum absorption concentration was 0.16–0.31 μg FMDV/μg LDH. In the mouse experiment, antibody levels in group LDH + FMDV were significantly higher compared to group saline + FMDV (P < 0.01) from days 42–98 and were significantly higher to group ISA-206 + FMDV on day 56 post-immunization (P < 0.05). After day 14 post-immunization, IFN-γ content was significantly increased (P < 0.05). In the pig experiment, antibody levels in both the ISA-206 + FMDV and LDH + FMDV were positive and were significantly higher compared with the PBS group on day 7 (P < 0.005). Antibody levels in 90% pigs were positive on day 56 in the LDH group. The neutralizing antibody levels in the LDH and ISA-206 groups were significantly higher from days 7–28 compared to the PBS control group (P < 0.05). Thus, LDH NPs were effective at inducing an immune response against FMDV.ConclusionsLDHs with a loose hexagonal shape and a positive charge were prepared and evaluated as adjuvant for FMD vaccine. It was demonstrated that LDHs can induce immune responses in mice and pigs. In addition, the LDHs produced antibodies continuously which may indicate a slow-release effect. The study shows that LDHs may act as a potentially useful FMDV adjuvant.

A ferritin nanoparticle vaccine for foot-and-mouth disease virus elicited partial protection in mice

Foot-and-mouth disease (FMD) is an acute, febrile, and highly contagious infectious disease common in cloven-hoofed animals. Outbreaks and epidemics of FMD can result in major economic losses of livestock. Using ferritin nanoparticles as the scaffold for an antigen can enhance the immunogenicity of the subunit vaccine and provide possible protection against FMD. We used a baculovirus expression system to express four recombinant proteins (VP1, VP1-Ft, G-H loop-Ft, and ferritin) and the protective immunity of the FMD ferritin nanoparticle vaccines was evaluated in mice. The recombinant subunit vaccines containing VP1, VP1-Ft, and G-H loop-Ft proteins significantly increased FMDV-specific IgG and IgG subclass antibody titers compared with the PBS group, as well as enhancing splenocyte proliferation and the expression of IL-4 and IFN-γ. The VP1 and VP1-Ft vaccines provided survival rates of 55.6% and 66.7%, respectively. The G-H loop-Ft vaccine provided a 77.8% survival rate compared with 100% survival in the inactivated vaccine group. The partial survival provided by the ferritin nanoparticle vaccines indicated that further study of the effects of the fused ferritin nanoparticle FMDV vaccines in animals is warranted.

The antibody response induced FMDV vaccines in sheep correlates with early transcriptomic responses in blood

Foot and mouth disease (FMD) is a highly contagious viral disease with high economic impact, representing a major threat for cloven-hooved mammals worldwide. Vaccines based on adjuvanted inactivated virus (iFMDV) induce effective protective immunity implicating antibody (Ab) responses. To reduce the biosafety constraints of the manufacturing process, a non-replicative human adenovirus type 5 vector encoding FMDV antigens (Ad5-FMDV) has been developed. Here we compared the immunogenicity of iFMDV and Ad5-FMDV with and without the ISA206VG emulsion-type adjuvant in sheep. Contrasted Ab responses were obtained: iFMDV induced the highest Ab levels, Ad5-FMDV the lowest ones, and ISA206VG increased the Ad5-FMDV-induced Ab responses to protective levels. Each vaccine generated heterogeneous Ab responses, with high and low responders, the latter being considered as obstacles to vaccine effectiveness. A transcriptomic study on total blood responses at 24 h post-vaccination revealed several blood gene module activities correlating with long-term Ab responses. Downmodulation of T cell modules’ activities correlated with high responses to iFMDV and to Ad5-FMDV+ISA206VG vaccines as also found in other systems vaccinology studies in humans and sheep. The impact of cell cycle activity depended on the vaccine types, as it positively correlated with higher responses to iFMDV but negatively to non-adjuvanted Ad5-FMDV. Finally an elevated B cell activity at 24 h correlated with high Ab responses to the Ad5-FMDV+ISA206VG vaccine. This study provides insights into the early mechanisms driving the Ab response induced by different vaccine regimens including Ad5 vectors and points to T cell modules as early biomarker candidates of different vaccine-type efficacy across species.

Hydrogen peroxide vapour is an effective replacement for Formaldehyde in a BSL4 Foot and mouth disease vaccine manufacturing facility.

An evaluation of the efficacy of 35% hydrogen peroxide vapour (HPV) against two strains of FMDV was conducted over a period of 6months. FMDV biological indicators were produced on-site using strains obtained from a commercial FMDV vaccine manufacturing process. FMDV biological indicators were distributed within a BSL4 laboratory and exposed to short duration hydrogen peroxide cycles. Variations in titre, support matrix (soiling), temperature and humidity were evaluated in a series of 16 exposures using over 200 individual FMDV indicators. Additional verification testing was performed in an operational material transfer lock to replicate real-world use. HPV was found to be efficacious in inactivating FMDV strains; the inoculum titre influenced the level of reduction achieved with the specified cycle. SIGNIFICANCE AND IMPACT OF THE STUDY: The classification of formaldehyde as a presumed human carcinogen has presented regulatory challenges for its continued use as a biocidal product. Institutions are actively seeking fumigants to replace formaldehyde and undertaking studies to validate biocidal efficacy, particularly in high-level biosafety facilities where the consequences of pathogen release can be extremely severe. This study builds on the already substantial scientific efficacy base of 35% hydrogen peroxide vapour and provides a comprehensive evaluation of the applicability of hydrogen peroxide vapour as a replacement for formaldehyde within a Foot & Mouth Disease (FMDV) vaccine manufacturing facility.

Using chloroform as a preservative for trivalent foot and mouth disease vaccine in comparison to thiomersal

Background: Chloroform has a potential value as a substitute for thiomersal as a preservative due to its high antibacterial and antifungal activity. Objectives: Comparative analysis of the preservative efficacy of chloroform and thiomersal in ISA206 trivalent foot and mouth disease vaccine concerning the antimicrobial activity and vaccine potency. Methods: This study was conducted on 5 prepared ISA206 trivalent foot and mouth disease vaccines, one vaccine prepared with 0.01% v/v thiomersal and four vaccines prepared with different concentrations of chloroform 0.1%, 0.25%, 0.5% and 0.75% v/v. Each vaccine was monthly evaluated by safety and sterility tests for 12 months. Three cattle were vaccinated intramuscularly (I/M) by each vaccine. Serum samples were collected monthly for 12 months. The humeral immune responses were monitored by Serum Neutralization Test (SNT) and Enzyme Linked Immunosorbent Assay (ELISA). The antimicrobial activity of chloroform and thiomersal in the five vaccines were determined 12 months post preparation against nine different gram negative and gram positive bacterial strains and three fungal stains. The bacterial strains were Bacillus subtilis, Staphylococcus aureus, Micrococcus luteus, Pseudo-monas aeruginosa, Escherichia coli, Salmonella typhi, Shig-ella flexneri, Salmonella para typhi A and Proteus mirabilis and fungal strains were Aspergillus flavus, Aspergillus nigar and Aspergillus pterus. Agar well diffusion method was followed in this study. The 12 monthes comparative analysis of antibacterial activity reflects that among these five vaccines shows thiomersal as well as 0.5% chloroform exhibiting maximum anti-bacterial and antifungal activity. Results: Our results show that the incorporation of chloroform into ISA206/ FMDV vaccine is as effective as thiomersal as a preservative. Conclusion: Finally we recommended using chloroform as a substitute for thiomersal as a preservative in foot and mouth disease vaccine.

Expression of the VP1 protein of FMDV integrated chromosomally with mutant Listeria monocytogenes strain induced both humoral and cellular immune responses.

Live vector-based vaccine is a modern approach to overcome the drawbacks of inactivated foot-and-mouth disease (FMD) vaccines such as improper inactivation during manufacture. Listeria monocytogenes (LM), an intracellular microorganism with immune-stimulatory properties, is appropriate to be utilized as a live bacterial vaccine vector. FMDV-VP1 protein has the capability to induce both cellular and humoral immune responses since it is considered the most immunogenic part of FMDV capsid and has the most of antigenic sites for viral neutralization. The codon-optimized vp1 gene was ligated to the integrative pCW702 plasmid to construct the target cassette. The antigen cassette was integrated successfully into the chromosome of mutant LM strain via homologous recombination for more stability to generate a candidate vaccine strain LM△actAplcB-vp1. Safety evaluation of recombinant LM△actAplcB-vp1 revealed it could be eliminated from the internal organs within 3days as a safe candidate vaccine. Mice groups were immunized I.V. twice with the recombinant LM△actAplcB-vp1 at an interval of 2weeks. Antigen-specific IgG antibodies and the level of CD4+- and CD8+-specific secreted cytokines were estimated to evaluate the immunogenicity of the candidate vaccine. The rapid onset immune response was detected, strong IgG humoral immune response within 14days post immunization and augmented again after the booster dose. Cellular immunity data after 9days post the prime dose indicated elevation in CD4+ and CD8+ secreted cytokine level with another elevation after the booster dose. This is the first report to explain the ability of attenuated mutant LM to be a promising live vector for FMDV vaccine.

Nanochitin-CBM conjugated protein for oral FMDV vaccine formulation

Nanochitin-CBM conjugated protein for oral FMDV vaccine formulation

Study on Real Correlation Between Foot And Mouth Disease Virus, Serotype (O) Neutralizing Antibody Titers And Protection Percentage In Vaccinated Calves

Foot and mouth disease (FMD) is a highly infectious and economically devastating disease of livestock. The vaccination is used for prevention of FMDV infection, while the evaluation of FMDV vaccine is mandatory to approve the efficacy of the vaccine but it consumed time and animals. This work, aimed to find the correlation between serum neutralization test (SNT) and challenge test by using FMDV serotype O (O/EGY/4/2012). Seventeen calves (6 months of age) were tested by SNT to be confirming their freedom from antibodies against serotype O. The calves were allotted into four groups. The first group (5 calves) was inoculated with field dose (1X) of a local inactivated FMDV vaccine (contain O/EGY/4/2012), the 2nd group (5 calves) was inoculated with half dose (1/2 X) of the same vaccine and the 3rd group (5 calves) was inoculated with one quarter dose (1/4 X) of the same previous vaccine, while the 4th group (2 calves) was kept as control. The sera were collected from group1, 2 and 3 at the 0, 14 and 28th day post vaccination. SNT was carried out against FMDV serotype O and the challenge test was carried out by inoculating all animals with 0.3 ml 104 BID50 (bovine infectious doses) of virulent FMDV type O. It was found that the SNT result after 28 days post vaccination for group1, group2 and group3 were 2.28, 1.74 and 0.96 (log10) TCID50/ml respectively while the protection percentage were 100%, 80% and 60% respectively. The recorded results reflect the correlation between serum neutralizing antibody titre and protective percentage in vaccinated calves which could be useful as alternative to challenge test in FMDV vaccine evaluation to minimize the cost of experimental animals use and suggested hazard.

Comparison of different inactivation methods on the stability of Indian vaccine strains of foot and mouth disease virus

In this study, the efficiency of binary ethyleneimine (BEI) in combination with formaldehyde (FA) and glutaraldehyde (GTA) in inactivating the Indian FMDV vaccine strains is compared. The acceptable safety of virus inactivation was faster and the inactivation rates were increased many-folds with combination of inactivants than BEI alone. FMDV A was inactivated rapidly than the other two serotypes with BEI + FA combination. Inactivation plots were linear for all the serotypes irrespective of inactivation process. Further, the integrity studies on 146S using serotype specific ELISA indicated no significant change in the antigenic mass of all the serotypes throughout the inactivation process. However, the loss of 146S antigen occurred in the subsequent steps of downstream processing. Further, the studies on intactness of viral RNA using real time PCR indicated the amplification of 1D gene sequences in all the preparations of timed samples irrespective of serotypes/inactivation process. Further, inactivated virus preparation (146S) was more stable at lower temperatures for all the serotypes/inactivation process. Among the combinations of inactivants, BEI + FA out performed compared to BEI + GTA and BEI in terms of inactivation rates, 146S yield and its storage stability, irrespective of the serotypes.