scholarly journals Early immune response in mice immunized with a semi-split inactivated vaccine against SARS-CoV-2 containing S protein-free particles and subunit S protein

2020 ◽  
Author(s):  
Marek Petráš ◽  
Petr Lesný ◽  
Jan Musil ◽  
Radomíra Limberková ◽  
Alžběta Pátíková ◽  
...  
Keyword(s):  
Cellular Immunity ◽  
Neutralizing Antibodies ◽  
Immune Cell ◽  
Geometric Mean ◽  
Inactivated Vaccine ◽  
S Protein ◽  
Humoral And Cellular Immunity ◽  
Wide Range ◽  
Immune Cell Response ◽  
Th1 And Th2 Lymphocytes

AbstractThe development of a vaccine against COVID-19 is a hot topic for many research laboratories all over the world. Our aim was to design a semi-split inactivated vaccine offering a wide range of multi-epitope determinants important for the immune system including not only the spike (S) protein but also the envelope, membrane and nucleocapsid proteins. We designed a semi-split vaccine prototype consisting of S protein-depleted viral particles and free S protein. Next, we investigated its immunogenic potential in BALB/c mice. The animals were immunized intradermally or intramuscularly with the dose adjusted with buffer or addition of aluminum hydroxide, respectively. The antibody response was evaluated by plasma analysis at 7 days after the first or second dose. The immune cell response was studied by flow cytometry analysis of splenocytes. The data showed a very early onset of both S protein-specific antibodies and virus-neutralizing antibodies at 90% inhibition regardless of the route of vaccine administration. However, significantly higher levels of neutralizing antibodies were detected in the intradermally (geometric mean titer - GMT of 7.8 ± 1.4) than in the intramuscularly immunized mice (GMT of 6.2 ± 1.5). In accordance with this, stimulation of cellular immunity by the semi-split vaccine was suggested by elevated levels of B and T lymphocyte subpopulations in the murine spleens. These responses were more predominant in the intradermally immunized mice compared with the intramuscular route of administration. The upward trend in the levels of plasmablasts, memory B cells, Th1 and Th2 lymphocytes, including follicular helper T cells, was confirmed even in mice receiving the vaccine intradermally at a dose of 0.5 μg.We demonstrated that the semi-split vaccine is capable of eliciting both humoral and cellular immunity early after vaccination. Our prototype thus represents a promising step toward the development of an efficient anti-COVID-19 vaccine for human use.

scholarly journals Effects of Spike Mutations in SARS-CoV-2 Variants of Concern on Human or Animal ACE2-Mediated Virus Entry and Neutralization

2021 ◽  
Author(s):  
Yunjeong Kim ◽  
Natasha N Gaudreault ◽  
David A Meekins ◽  
Krishani D Perera ◽  
Dashzeveg Bold ◽  
...  
Keyword(s):  
Viral Entry ◽  
Neutralizing Antibodies ◽  
Animal Species ◽  
Virus Entry ◽  
Neutralizing Antibody ◽  
Protein S ◽  
Pseudotyped Virus ◽  
S Protein ◽  
Viral Neutralization ◽  
Wide Range

SARS-CoV-2 is a zoonotic agent capable of infecting humans and a wide range of animal species. Over the duration of the pandemic, mutations in the SARS-CoV-2 Spike protein (S) have arisen in circulating viral populations, culminating in the spread of several variants of concern (VOC) with varying degrees of altered virulence, transmissibility, and neutralizing antibody escape. In this study, we employed lentivirus-based pseudotyped viruses that express specific SARS-CoV-2 S protein substitutions and cell lines that stably express ACE2 from nine different animal species to gain insights into the effects of VOC mutations on viral entry and antibody neutralization capability. All animal ACE2 receptors tested, except mink, support viral cell entry for pseudoviruses expressing the parental (prototype Wuhan-1) S at levels comparable to human ACE2. Most single S substitutions (e.g., 452R, 478K, 501Y) did not significantly change virus entry, although 614G and 484K resulted in a decreased efficiency in viral entry.  Conversely, combinatorial VOC substitutions in the S protein were associated with significantly increased entry capacity of pseudotyped viruses compared to that of the parental Wuhan-1 pseudotyped virus. Similarly, infection studies using live ancestral (USA-WA1/2020), Alpha, and Beta SARS-CoV-2 viruses in hamsters revealed a higher replication potential for the Beta variant compared to the ancestral prototype virus. Moreover, neutralizing titers in sera from various animal species, including humans, were significantly reduced by single substitutions of 484K or 452R, double substitutions of 501Y-484K, 452R-484K and 452R-478K and the triple substitution of 501Y-484K-417N, suggesting that 484K and 452R are particularly important for evading neutralizing antibodies in human, cat, and rabbit sera. Cumulatively, this study reveals important insights into the host range of SARS-CoV-2 and the effect of recently emergent S protein substitutions on viral entry, virus replication and antibody-mediated viral neutralization.

scholarly journals Synthetic SARS-CoV-2 Spike-Based DNA Vaccine Elicits Robust and Long-Lasting Th1 Humoral and Cellular Immunity in Mice

2021 ◽  
Vol 12 ◽  
Author(s):  
Sawsan S. Alamri ◽  
Khalid A. Alluhaybi ◽  
Rowa Y. Alhabbab ◽  
Mohammad Basabrain ◽  
Abdullah Algaissi ◽  
...  
Keyword(s):  
Dna Vaccine ◽  
Cellular Immunity ◽  
Neutralizing Antibodies ◽  
Humoral Response ◽  
Igg Antibodies ◽  
Free System ◽  
Humoral And Cellular Immunity ◽  
Global Pandemic ◽  
Therapeutic Measures ◽  
Needle Injection

The ongoing global pandemic of coronavirus disease 2019 (COVID-19) calls for an urgent development of effective and safe prophylactic and therapeutic measures. The spike (S) glycoprotein of severe acute respiratory syndrome-coronavirus (SARS-CoV-2) is a major immunogenic and protective protein and plays a crucial role in viral pathogenesis. In this study, we successfully constructed a synthetic codon-optimized DNA-based vaccine as a countermeasure against SARS-CoV-2, denoted VIU-1005. The design was based on a codon-optimized coding sequence of a consensus full-length S glycoprotein. The immunogenicity of the vaccine was tested in two mouse models (BALB/c and C57BL/6J). Th1-skewed systemic S-specific IgG antibodies and neutralizing antibodies (nAbs) were significantly induced in both models 4 weeks after three injections with 100 μg of the VIU-1005 vaccine via intramuscular needle injection but not intradermal or subcutaneous routes. Such immunization induced long-lasting IgG and memory T cell responses in mice that lasted for at least 6 months. Interestingly, using a needle-free system, we showed an enhanced immunogenicity of VIU-1005 in which lower or fewer doses were able to elicit significantly high levels of Th1-biased systemic S-specific immune responses, as demonstrated by the significant levels of binding IgG antibodies, nAbs and IFN-γ, TNF and IL-2 cytokine production from memory CD8+ and CD4+ T cells in BALB/c mice. Furthermore, compared to intradermal needle injection, which failed to induce any significant immune response, intradermal needle-free immunization elicited a robust Th1-biased humoral response similar to that observed with intramuscular immunization. Together, our results demonstrate that the synthetic VIU-1005 candidate DNA vaccine is highly immunogenic and capable of inducing long-lasting Th1-skewed humoral and cellular immunity in mice. Furthermore, we show that the use of a needle-free system could enhance the immunogenicity and minimize doses needed to induce protective immunity in mice, supporting further preclinical and clinical testing of this candidate vaccine.

scholarly journals A class II MHC-targeted vaccine elicits immunity against SARS-CoV-2 and its variants

2021 ◽  
Vol 118 (44) ◽  
pp. e2116147118
Author(s):  
Novalia Pishesha ◽  
Thibault J. Harmand ◽  
Paul W. Rothlauf ◽  
Patrique Praest ◽  
Ryan K. Alexander ◽  
...  
Keyword(s):  
Cellular Immunity ◽  
Neutralizing Antibodies ◽  
High Titer ◽  
Developed Countries ◽  
Class Ii ◽  
T Cell Response ◽  
Humoral And Cellular Immunity ◽  
Histocompatibility Complex ◽  
Class Ii Mhc ◽  
Antigen Presenting

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in over 100 million infections and millions of deaths. Effective vaccines remain the best hope of curtailing SARS-CoV-2 transmission, morbidity, and mortality. The vaccines in current use require cold storage and sophisticated manufacturing capacity, which complicates their distribution, especially in less developed countries. We report the development of a candidate SARS-CoV-2 vaccine that is purely protein based and directly targets antigen-presenting cells. It consists of the SARS-CoV-2 Spike receptor-binding domain (SpikeRBD) fused to an alpaca-derived nanobody that recognizes class II major histocompatibility complex antigens (VHHMHCII). This vaccine elicits robust humoral and cellular immunity against SARS-CoV-2 and its variants. Both young and aged mice immunized with two doses of VHHMHCII-SpikeRBD elicit high-titer binding and neutralizing antibodies. Immunization also induces strong cellular immunity, including a robust CD8 T cell response. VHHMHCII-SpikeRBD is stable for at least 7 d at room temperature and can be lyophilized without loss of efficacy.

scholarly journals Safety and immunogenicity of a heterologous boost with a recombinant vaccine, NVSI-06-07, in the inactivated vaccine recipients from UAE: a phase 2 randomised, double-blinded, controlled clinical trial

2022 ◽  
Author(s):  
Nawal AlKaabi ◽  
Yun Kai Yang ◽  
Jing Zhang ◽  
Ke Xu ◽  
Yu Liang ◽  
...  
Keyword(s):  
United Arab Emirates ◽  
Neutralizing Antibodies ◽  
Geometric Mean ◽  
Prototype Strain ◽  
Controlled Clinical Trial ◽  
Inactivated Vaccine ◽  
Phase 2 ◽  
Significant Difference ◽  
Double Blinded ◽  
Heterologous Boost

Background: The increased coronavirus disease 2019 (COVID-19) breakthrough cases pose the need of booster vaccinations. In this study, we reported the safety and immunogenicity of a heterologous boost with a recombinant COVID-19 vaccine (CHO cells), named NVSI-06-07, as a third dose in participants who have previously received two doses of the inactivated vaccine (BBIBP-CorV) at pre-specified time intervals. Using homologous boost with BBIBP-CorV as control, the safety and immunogenicity of the heterologous boost with NVSI-06-07 against various SARS-CoV-2 strains, including Omicron, were characterized. Methods: This study is a single-center, randomised, double-blinded, controlled phase 2 trial for heterologous boost of NVSI-06-07 in BBIBP-CorV recipients from the United Arab Emirates (UAE). Healthy adults (aged ≥18 years) were enrolled and grouped by the specified prior vaccination interval of BBIBP-CorV, i.e., 1-3 months, 4-6 months or ≥6 months, respectively, with 600 individuals per group. For each group, participants were randomly assigned at 1:1 ratio to receive either a heterologous boost of NVSI-06-07 or a homologous booster dose of BBIBP-CorV. The primary outcome was to comparatively assess the immunogenicity between heterologous and homologous boosts at 14 and 28 days post-boosting immunization, by evaluation of the geometric mean titers (GMTs) of IgG and neutralizing antibodies as well as the corresponding seroconversion rate (≥4-fold rise in antibody titers). The secondary outcomes were the safety profile of the boosting strategies within 30 days post vaccination. The exploratory outcome was the immune efficacy against Omicron and other variants of concern (VOCs) of SARS-CoV-2. This trial is registered with ClinicalTrials.gov, NCT05033847. Findings: A total of 1800 individuals who have received two doses of BBIBP-CorV were enrolled, of which 899 participants received a heterologous boost of NVSI-06-07 and 901 received a homologous boost for comparison. No vaccine-related serious adverse event (SAE) and no adverse events of special interest (AESI) were reported. 184 (20.47%) participants in the heterologous boost groups and 177 (19.64%) in the homologous boost groups reported at least one adverse reaction within 30 days. Most of the local and systemic adverse reactions reported were grades 1 (mild) or 2 (moderate), and there was no significant difference in the overall safety between heterologous and homologous boosts. Immunogenicity assays showed that the seroconversion rates in neutralizing antibodies against prototype SARS-CoV-2 elicited by heterologous boost were 89.96% - 97.52% on day 28 post-boosting vaccination, which was much higher than what was induced by homologous boost (36.80% - 81.75%). Similarly, in heterologous NVSI-06-07 booster groups, the neutralizing geometric mean titers (GMTs) against the prototype strain increased by 21.01 - 63.85 folds from baseline to 28 days post-boosting vaccination, whereas only 4.20 - 16.78 folds of increases were observed in homologous BBIBP-CorV booster group. For Omicron variant, the neutralizing antibody GMT elicited by the homologous boost of BBIBP-CorV was 37.91 (95%CI, 30.35-47.35), however, a significantly higher level of neutralizing antibodies with GMT 292.53 (95%CI, 222.81-384.07) was induced by the heterologous boost of NVSI-06-07, suggesting that it may serve as an effective boosting strategy combating the pandemic of Omicron. The similar results were obtained for other VOCs, including Alpha, Beta and Delta, in which the neutralizing response elicited by the heterologous boost was also significantly greater than that of the homologous boost. In the participants primed with BBIBP-CorV over 6 months, the largest increase in the neutralizing GMTs was obtained both in the heterologous and homologous boost groups, and thus the booster vaccination with over 6 months intervals was optimal. Interpretation: Our findings indicated that the heterologous boost with NVSI-06-07 was safe, well-tolerated and immunogenic in adults primed with a full regimen of BBIBP-CorV. Compared to homologous boost with a third dose of BBIBP-CorV, incremental increases in immune responses were achieved by the heterologous boost with NVSI-06-07 against SARS-CoV-2 prototype strain, Omicron variant, and other VOCs. The heterologous BBIBP-CorV/NVSI-06-07 prime-boosting vaccination may be valuable in preventing the pandemic of Omicron. The optimal booster strategy was the heterologous boost with NVSI-06-07 over 6 months after a priming with two doses of BBIBP-CorV.

scholarly journals Immunogenicity and Safety of a Three-Dose Regimen of a SARS-CoV-2 Inactivated Vaccine in Adults: A Randomized, Double-blind, Placebo-controlled Phase 2 Trial

2021 ◽  
Author(s):  
Jiankai Liu ◽  
Baoying Huang ◽  
Guifan Li ◽  
Xianyun Chang ◽  
Yafei Liu ◽  
...  
Keyword(s):  
Neutralizing Antibodies ◽  
Controlled Trial ◽  
Geometric Mean ◽  
Inactivated Vaccine ◽  
Phase 2 ◽  
Igg Antibody ◽  
Double Blind ◽  
Younger Adults ◽  
Live Virus ◽  
Double Blind Placebo

Abstract Background Control of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic needs effective vaccines. Methods In a phase 2 randomized, double-blind, placebo-controlled trial, 500 adults aged 18-59 years or ≥60 years were randomized in 2:2:1 ratio to receive 3 doses of 5-μg or 10-μg of a SARS-CoV-2 inactivated vaccine, or placebo separated by 28 days. Adverse events (AEs) were recorded through Day 28 after each dosing. Live virus or pseudovirus neutralizing antibodies, and receptor binding domain (RBD-IgG) antibody were tested after the second and third doses. Results Two doses of the vaccine elicited geometric mean titers (GMTs) of 102-119, 170-176, and 1449-1617 for the three antibodies in younger adults. Pseudovirus neutralizing and RBD-IgG GMTs were similar between older and younger adults. The third dose slightly (<1.5 folds) increased GMTs. Seroconversion percentages were 94% or more after two doses, which were generally similar after three doses. The predominant AEs were injection-site pain. All the AEs were grade 1 or 2 in intensity. No serious AE was deemed related to study vaccination. Conclusions Two doses of this vaccine induced robust immune response and had good safety profile. A third dose given 28 days after the second dose elicited limited boosting antibody response.

scholarly journals Self-Assembling Nanovaccine Enhances Protective Efficacy Against CSFV in Pigs

2021 ◽  
Vol 12 ◽  
Author(s):  
Ze-Hui Liu ◽  
Hui-Ling Xu ◽  
Guang-Wei Han ◽  
Li-Na Tao ◽  
Ying Lu ◽  
...  
Keyword(s):  
Cellular Immunity ◽  
Neutralizing Antibodies ◽  
Protective Efficacy ◽  
Genetically Engineered ◽  
Swine Industry ◽  
Antigen Uptake ◽  
Virus Challenge ◽  
Humoral And Cellular Immunity ◽  
Self Assembling

Classical swine fever virus (CSFV) is a highly contagious pathogen, which pose continuous threat to the swine industry. Though most attenuated vaccines are effective, they fail to serologically distinguish between infected and vaccinated animals, hindering CSFV eradication. Beneficially, nanoparticles (NPs)-based vaccines resemble natural viruses in size and antigen structure, and offer an alternative tool to circumvent these limitations. Using self-assembling NPs as multimerization platforms provides a safe and immunogenic tool against infectious diseases. This study presented a novel strategy to display CSFV E2 glycoprotein on the surface of genetically engineered self-assembling NPs. Eukaryotic E2-fused protein (SP-E2-mi3) could self-assemble into uniform NPs as indicated in transmission electron microscope (TEM) and dynamic light scattering (DLS). SP-E2-mi3 NPs showed high stability at room temperature. This NP-based immunization resulted in enhanced antigen uptake and up-regulated production of immunostimulatory cytokines in antigen presenting cells (APCs). Moreover, the protective efficacy of SP-E2-mi3 NPs was evaluated in pigs. SP-E2-mi3 NPs significantly improved both humoral and cellular immunity, especially as indicated by the elevated CSFV-specific IFN-γ cellular immunity and >10-fold neutralizing antibodies as compared to monomeric E2. These observations were consistent to in vivo protection against CSFV lethal virus challenge in prime-boost immunization schedule. Further results revealed single dose of 10 μg of SP-E2-mi3 NPs provided considerable clinical protection against lethal virus challenge. In conclusion, these findings demonstrated that this NP-based technology has potential to enhance the potency of subunit vaccine, paving ways for nanovaccine development.

scholarly journals SARS-CoV-2 acquisition and immune pathogenesis among school-aged learners in four diverse schools

2021 ◽  
Author(s):  
Dan M. Cooper ◽  
Michael Z. Zulu ◽  
Allen Jankeel ◽  
Izabela Coimbra Ibraim ◽  
Jessica Ardo ◽  
...  
Keyword(s):  
Immune Responses ◽  
Low Income ◽  
Neutralizing Antibodies ◽  
Mitigation Strategies ◽  
Student Diversity ◽  
List Type ◽  
Diverse Range ◽  
Humoral And Cellular Immunity ◽  
Wide Range ◽  
Diverse Schools

Abstract Background Understanding SARS-CoV-2 infection in children is necessary to reopen schools safely. Methods We measured SARS-CoV-2 infection in 320 learners [10.5 ± 2.1 (sd); 7–17 y.o.] at four diverse schools with either remote or on-site learning. Schools A and B served low-income Hispanic learners; school C served many special-needs learners, and all provided predominantly remote instruction. School D served middle- and upper-income learners, with predominantly on-site instruction. Testing occurred in the fall (2020), and 6–8 weeks later during the fall-winter surge (notable for a tenfold increase in COVID-19 cases). Immune responses and mitigation fidelity were also measured. Results We found SARS-CoV-2 infections in 17 learners only during the surge. School A (97% remote learners) had the highest infection (10/70, 14.3%, p < 0.01) and IgG positivity rates (13/66, 19.7%). School D (93% on-site learners) had the lowest infection and IgG positivity rates (1/63, 1.6%). Mitigation compliance [physical distancing (mean 87.4%) and face-covering (91.3%)] was remarkably high at all schools. Documented SARS-CoV-2-infected learners had neutralizing antibodies (94.7%), robust IFN-γ + T cell responses, and reduced monocytes. Conclusions Schools can implement successful mitigation strategies across a wide range of student diversity. Despite asymptomatic to mild SARS-CoV-2 infection, children generate robust humoral and cellular immune responses. Impact Successful COVID-19 mitigation was implemented across a diverse range of schools. School-associated SARS-CoV-2 infections reflect regional rates rather than remote or on-site learning. Seropositive school-aged children with asymptomatic to mild SARS-CoV-2 infections generate robust humoral and cellular immunity.

scholarly journals Vaccine-induced humoral and cellular immunity against SARS-CoV-2 at 6 months post BNT162b2 vaccination

2021 ◽  
Author(s):  
Hideaki Kato ◽  
Kei Miyakawa ◽  
Norihisa Ohtake ◽  
Yutaro Yamaoka ◽  
Satoshi Yajima ◽  
...  
Keyword(s):  
Cellular Immunity ◽  
Healthy Subjects ◽  
Elispot Assay ◽  
Geometric Mean ◽  
Neutralizing Antibody ◽  
Interferon Γ ◽  
Spike Protein ◽  
Cell Mediated Immunity ◽  
Humoral And Cellular Immunity ◽  
Cell Counts

To evaluate vaccine-induced humoral and cell-mediated immunity at 6 months post BNT162b2 vaccination, immunoglobulin G against SARS-CoV-2 spike protein (SP IgG), 50% neutralizing antibody (NT50), and spot-forming cell (SFC) counts were evaluated by interferon-γ releasing ELISpot assay of 98 healthy subjects (median age, 43 years). The geometric mean titers of SP IgG and NT50 decreased from 95.2 (95% confidence interval (CI) 79.8-113.4) to 5.7 (95% CI 4.9-6.7) and from 680.4 (588.0-787.2) to 130.4 (95% CI 104.2-163.1), respectively, at 3 weeks and 6 months after the vaccination. SP IgG titer was negatively correlated with age and alcohol consumption. Spot-forming cell counts at 6 months did not correlate with age, gender, and other parameters of the patients. SP IgG, NT50, and SFC titers were elevated in the breakthrough infected subjects. Although the levels of vaccine-induced antibodies dramatically declined at 6 months after vaccination, a certain degree of cellular immunity was observed irrespective of the age.

scholarly journals Longitudinal characterization of humoral and cellular immunity in hospitalized COVID-19 patients reveal immune persistence up to 9 months after infection

2021 ◽  
Author(s):  
John Tyler Sandberg ◽  
Renata Varnaitė ◽  
Wanda Christ ◽  
Puran Chen ◽  
Jagadeeswara R. Muvva ◽  
...  
Keyword(s):  
T Cell ◽  
B Cell ◽  
Cellular Immunity ◽  
Symptom Onset ◽  
Neutralizing Antibodies ◽  
Severe Disease ◽  
Neutralizing Antibody ◽  
Immune Memory ◽  
Humoral And Cellular Immunity ◽  
Cell Responses

AbstractBackgroundInsights into early, specific humoral and cellular responses to infection with SARS-CoV-2, as well as the persistence and magnitude of resulting immune memory is important amidst the ongoing pandemic. The combination of humoral and cellular immunity will most likely contribute to protection from reinfection or severe disease.MethodsHere, we conducted a longitudinal study on hospitalized moderate and severe COVID-19 patients from the acute phase of disease into convalescence at five- and nine-months post symptom onset. Utilizing flow cytometry, serological assays as well as B cell and T cell FluoroSpot assays, we assessed the magnitude and specificity of humoral and cellular immune memory during and after human SARS-CoV-2 infection.FindingsDuring acute COVID-19, we observed an increase in germinal center activity, a substantial expansion of antibodysecreting cells, and the generation of SARS-CoV-2-neutralizing antibodies. Despite gradually decreasing antibody levels, we show persistent, neutralizing antibody titers as well as robust specific memory B cell responses and polyfunctional T cell responses at five- and nine-months after symptom onset in both moderate and severe COVID-19 patients. Long-term SARS-CoV-2 specific responses were marked by preferential targeting of spike over nucleocapsid protein.ConclusionsOur findings describe the initiation and, importantly, persistence of cellular and humoral SARS-CoV-2 specific immunological memory in hospitalized COVID-19 patients long after recovery, likely contributing towards protection against reinfection.

scholarly journals NEW INACTIVATED VACCINE AGAINST ENZOOTIC ENCEPHALOMYELITIS OF SWINES

2013 ◽  
Vol 17 ◽  
pp. 170-184
Author(s):  
S. V. Derevianko ◽  
V. I. Soroka ◽  
T. O. Bowa
Keyword(s):  
Neutralizing Antibodies ◽  
Virulent Strain ◽  
Geometric Mean ◽  
Vaccine Dose ◽  
Maximum Level ◽  
Original Method ◽  
Inactivated Vaccine ◽  
Technical Requirements ◽  
High Level ◽  
And Control

A specific inactivated vaccine for prevention of enzootic encephalomyelitis (Teschen disease) of swines was created. The vaccine is produced on the basis of «Dniprovskiy-34» strain of Porcine teschovirus-1 isolated in the Ukraine and adjuvant of ASRIAP. During vaccines production the original method of teshoviruses inactivation was used. A single vaccine dose of 2 cubic cm promotes specific swines immunity to Teschen disease remaining for 11 months. Protective antibody levels were observed on the 7th day after vaccination. The maximum level of virus neutralizing antibodies in the blood of vaccinated animals on 60th day have reached 1:8192. Geometric mean titer of antibodies is 1:512, which protects the vaccinated piglets even at intracerebral introduction of 10 lethal doses of control epizootic highly virulent strain of Teschen disease of swines «Chernihivskiy-2372». A high level of innovative product design was confirmed by commission tests conducted in cooperation with State Scientific Control Institute of Biotechnology and Microorganism Strains and protected with three patents of Ukraine for inventions and useful models. A normative product documentation (Technical Requirements of Ukraine, instructions for production and control and product insert) was created. Performed feasibility study of the «Teshovak» vaccine allows recommending it into the production and introduction into the practices of veterinary medicine.

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