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The genetic variability of population may explain different individual immune responses to the SARS-CoV-2 virus. The use of genome- and peptidome-based technologies makes it possible to develop vaccines by optimizing the target antigens. The computer modeling methodology provides the scientific community with a more complete list of immunogenic peptides, including a number of new and cross-reactive candidates. Studies conducted independently of each other with different approaches provide a high degree of confidence in the reproducibility of results. Most of the effort in developing vaccines and drugs against SARS-CoV-2 is directed towards the thorn glycoprotein (protein S), a major inducer of neutralizing antibodies. Several vaccines have been shown to be effective in the preclinical studies and have been tested in the clinical trials to combat the COVID-19 infection. This review presents the profile of in silico predicted immunogenic peptides of the SARS-CoV-2 virus for the subsequent functional validation and vaccine development, and highlights the current advances in the development of subunit vaccines to combat COVID-19, taking into account the experience that has been previously achieved with SARS-CoV and MERS-CoV. The immunoinformatics techniques reduce the time and cost of developing vaccines that together can stop this new viral infection.

A hybrid recombinant protein containing the amino acid sequences of the three most significant Pseudomonas aeruginosa antigens (membrane proteins OprF, OprI and toxoid aTox) was incorporated into a vaccine against Pseudomonas infection. Quality control of a hybrid recombinant protein and appropriate vaccine includes determination of authentity and completeness of adsorption upon aluminum hydroxide adjuvant. The aim of our study was to develop techniques of quality control for a vaccine based on the hybrid OprF-aToxOprI recombinant protein specific to P. aeruginosa. Hybridomas secreting specific monoclonal antibodies for OprF-aTox-OprI were derived from the fusion of myeloma cells and murine spleen cells immunized with recombinant proteins P. aeruginosa. To produce sufficient quantities of antibodies, the hybrid cells were in vivo cultured in BALB/c mice. Supernates and ascite liquids were chromatographically purified with immune sorbent. Conjugation of antibodies with horseradish peroxidase was carried out according to P.K.Nakane. The hybrid OprF-aTox-OprI recombinant protein was detected by the solid-phase ELISA, using a panel of monoclonal antibodies and conjugates of monoclonal antibodies with horseradish peroxidase. Monoclonal antibodies were specific for different OprF-aTox-OprI epitopes. Titration assays containing OprF-aTox-OprI protein at 78 ng/ml to 5000 ng/ml were used as quantitative standards for calibration curves.To identify the recombinant protein OprF-aTox-OprI, 55 variants of of MAb pairs were tested. Limits of quantitative detection served for selection of most sensitive and specific ELISA variants. The quantitative detection limit was calculated for all 11 ELISA variants. Two ELISA variants with the highest sensitivity were selected for quality control of the hybrid recombinant protein. The limits of quantitative detection were, respectively, 2.9 and 13.6 ng/ml (0.0058 and 0.027% of the estimated antigen content in the vaccine) for the first and second ELISA variants. The first variant included a pair of monoclonal antibodies specific for the OprF and OprI epitopes, the second variant represented aTox and OprI epitopes. Two variants of ELISA were developed to detect the hybrid recombinant OprF-aTox-OprI protein. The first variant allows to determine the protein amount and to evaluate completeness of its adsorption on aluminum hydroxide. To confirm authenticity of the protein, both methods must be used, since they can detect all three antigens (OprF, aTox and OprI) which are present in the fusion protein.

Relevance. Coronavirus SARS-Cov-2 is a novel virus demonstrating the ability to be trans¬mitted from human-to-human, via respiratory droplets or close contact, and cause the severe acute respiratory syndrome (SARS). The role of its structural proteins in the SARS pathogenesis is unknown.Aim is to characterize the features of the SARS-Cov-2 structural proteins and their changes associated with acquiring other way of transmission and analyze the possibility of heterologous immunity emergence in its infection. Materials and method. For the computer analysis and alignment, the gene sequences of SARS-Cov-2 , SARS-CoV , MERS-CoV и bat CoV HKU3 reference strains were used from the Internet. From the primary structure of their genes it were translated their structural proteins: spike (S), envelope (E),membrane (M), and nucleocapsid (N). The genetic code of structural proteins was also defined. The search of homologous sequences in the SARS-Cov-2 S-protein, surface proteins of other viruses, and human proteins was made to find immune epitope continuum of protein relationships.Results. In the SARS-Cov-2 structural proteins amino acid sequences of M, E, and N-proteins are conservative. The S1 subunit of the S-protein contains some large insertions, significant changes of the amino acid content with the predominance of arginine and lysine which is typical for the surface glycoproteins in the viruses possessing high contagiousness. The S2 subunit is rather conservative and retain negative polarity. The S-protein exhibits the immune epitope relationships with many proteins of viruses and human which may be associated with immune collisions.Conclusion: The SARSCov-2 features are determined by marked changes of the S1 subunit structure in the S-protein which may be responsible for its contagiousness and many immune collisions aggravating infection process.

We aimed to assess autoantibodies to M2-cholinoceptors (M2-CR) in patients with paroxysmal lone atrial fibrillation (AF) and in patients with AF and arterial hypertension (AH).100 patients with lone AF and 84 patients with AF and AH were included. Patients underwent clinical blood and urinalysis, assessment of biochemistry blood panel, 12-lead ECG, 24-hour Holter monitoring, echocardiography and stress - testing (treadmill or stress - echocardiography). Assessment of IgM and IgG autoantibodies to M2-CR was performed by indirect immunoenzyme assay. The following peptide molecules were used as epitopes for detection of autoantibodies: M1 - amino acid sequence YTVIGYWPLGVVCDL (83-98) of the first extracellular loop of M2-CR; M2 - sequence VRTVEDGECYIQFFSNAAVTFGTAI (168-192) of the second extracellular loop of M2-CR; M3 - sequence NTFCAPCIPNTV (410-421) of the third extracellular loop of M2-CR; M4 - short sequence VEDGECYIQFFS (171-182) of the second extracellular loop of M2-CR; M1+M4 - chimeric molecule formed by sequences of the first and the second extracellular loops of M2-CR connected by disulfide bound YTVIGYWPLGVVCDL + VEDGECYIQFFS (83-98 + 171-182).Autoantibodies to M2-CR were found in 45% patients with lone AF and in 35% patients with AF and AH. In patients with lone AF prevalence of increased IgG to M2-CR were greater than in patients with AF and AH (32% vs 20%; p.Цель. Определение аутоантител к М2-холинорецепторам (М2-ХР) у больных пароксизмальной формой идиопатической фибрилляции предсердий (ФП), больных ФП в сочетании с гипертонической болезнью (ГБ), и оценка их возможной роли в развитии и поддержании аритмии. Материалы и методы. В исследование включали больных идиопатической пароксизмальной формой ФП (n=100) и больных ФП в сочетании с ГБ (n=84) моложе 66 лет. Больным проводили общеклинические анализы крови и мочи, биохимический анализ крови, регистрацию электрокардиограммы (ЭКГ), эхокардиографию, суточное мониторирование ЭКГ по Холтеру, пробу с дозированной физической нагрузкой. Определение аутоантител иммуноглобулинов (Ig) M и IgG к различным аминокислотным последовательностям М2-ХР проводили унифицированным непрямым иммуноферментным анализом. В качестве антигенных детерминант для выявления аутоантител выбраны следующие пептидные фрагменты внеклеточных петель молекулы М2-ХР: М1 - аминокислотная последовательность YTVIGYWPLGVVCDL (83-98) 1-й внеклеточной петли; M2 - аминокислотная последовательность VRTVEDGECYIQFFSNAAVTFGTAI (168-192) 2-й внеклеточной петли; M3 - аминокислотная последовательность NTFCАPCIPNTV (410-421) 3-й внеклеточной петли; M4 - короткая аминокислотная последовательность VEDGECYIQFFS (171-182) 2-й внеклеточной петли; M1+M4 - синтетическая химерная молекула, образованная аминокислотной последовательностью 1-й внеклеточной петли, связанной с короткой аминокислотной последовательностью 2-й внеклеточной петли посредством дисульфидной связи YTVIGYWPLGVVCDL + VEDGECYIQFFS (83-98 + 171-182). Результаты. Аутоантитела к различным аминокислотным последовательностям М2-ХР обнаружены у 45% больных идиопатической ФП и у 35% больных ФП в сочетании с ГБ. У пациентов с идиопатической ФП существенно чаще обнаруживалось значимое повышение IgG к М2-ХР по сравнению с группой больных ФП в сочетании с ГБ (32% против 20%; p.

Aim. The purpose of this study is to create the technology of preparation of the polymeric allergoid received by chemical modification of Dermatophagoides farinae extract by a formaldehyde and a monomeric allergoid of Dermatophagoides pteronyssinus received by succinilation and studying of their physical, chemical and immunologic properties. Materials and methods . In the modification species determined the protein content, isoelectric points of protein components by a method of isoelectrofocusing (IEF), esterase activity. Antigenic properties of allergoid studied by methods of an immunodiffusion and an immunoelectrophoresis. Applied microdot immunoenzyme assay to characterize the specific activity of a resulting allergoid. Received by a succinilation allergoid was also studied on physical and chemical indicators. Results. It is established That the formalinization is resulted by the expressed depression of allergenic activity of an allergoid. It is also shown that succinilation leads to essential depression of allergenicity of a monomeric allergoid due to blockade of B-cellular epitopes and to conservation of an adjuvanticity helps to T-cellular epitopes. Conclusion. Thanks to the proved depression of allergenicity and rising of an adjuvanticity monomeric and polymeric allergoid can be recommended for carrying out allergenspecific immunotherapy (ASIT).

Aim. In this study we aimed to develop the methodology to change the antigen specificity of chimeric antibodies by replacing the variable region genes in the previously designed universal plasmid constructions pLK DT-17 and pHG DT-17 encoding the DT-17 antibody against the diphtheria toxin (DT) to the genes of antibody binding to another DT epitope — DT-22. Materials and methods. The genes of the light and heavy chain variable regions of mouse anti-DT antibodies — DT-22 were amplified from the hybridoma producing monoclonal antibodies to DT by reverse transcription and PCR methods. Genetic engineering methods were used to replace the variable regions of DT-17 antibody in the recombinant plasmids pLK DT-17 and pHG DT-17 encoding the light and heavy chains of DT-17 antibody, respectively to the relevant genes of DT-22. Subsequently, a «supervector» pSV DT-22, containing the genes of both chains of the chimeric antibody, was designed. CHO cells were transfected with a «supervector» and a highly productive clone, secreting chimeric antibodies to DT was obtained. Immunochemical and cultural methods were used to evaluate antibody activity. The affinity chromatography was used to purified preparative amounts of antibodies. Results. The yield of purified secreted chimeric DT-22 antibodies was 4 mg from per liter of culture medium. The minimum concentration of chimeric antibodies at which DT was neutralized in the CHO cells was 22 μg/mL of medium. Conclusion. Thus it has been shown how to generate new vector coding synthesis of light and heavy chains of a chimeric DT-22 antibody specific to another DT epitope using previously constructed universal recombinant plasmids pLK DT-17 and pHG DT-17 encoding, light and heavy chains of antibodies against DT DT-17, respectively.

Aim. The aim of the study was to evaluate the ability of pMEL-TCI and pMEL-A0201 DNA-constructs encoding artificial polyepitope melanoma antigens to induce antitumor T cell immune response ex vivo. material and methods. Dendritic cells were obtained from peripheral blood mononuclear cells of HLA-A02:01-positive donors; DCs transfected with target DNA vaccine constructions were co-cultured with autologous T lymphocytes to stimulate anti-tumor effector T cells. Specific activity of ex vivo stimulated PBMC was assessed (1) by their ability to cause lysis of human melanoma Mel Is cells, and (2) by the level of their granzyme-producing activity. A recombinant plasmid encoding the full-length MART-1 melanoma antigen was used as a positive control. results. All DNA vaccine constructions as well as positive control construction were found to be able to stimulate specific anti-tumor immune responses of autologous PBMC ex vivo, and these PBMC were found to induce melanoma Mel Is cells lysis. Both the efficiency of induced cytotoxic responses and the level of granzymes production stimulated with DCs transfected with pMel-A0201 significantly exceeded those stimulated with DCs transfected with either pMel-TCI or with DNA construction encoding the full-length MART-1 protein. The cytotoxicity level correlates with the level of granzyme B production in CD8+ T lymphocytes. conclusion. DNA vaccine constructions encoding artificial polypeptides composed of tumor antigen epitopes can stimulate the antitumor cytotoxic response. This approach can be used as the basis for the development of new methods of immunotherapy for cancer.

The problem of the discrepancy between serotypes of the circulating strains of hepatitis B virus and serotype of the HBsAg in the vaccine is discussed. The results of published scientific studies show that hepatitis B vaccines containing HBsAg serotype ad provide good, but not optimal, protection against heterologous serotypes of the virus. The authors conclude that the use of vaccines containing HBsAg serotype typical for given territory is a priority. Further in-depth studies on this issue are needed to clarify the available scientific evidence.

The problem of antibody-mediated rejection of donor organ remains extremely relevant. The main targets of the antibodies are mainly donor HLA-antigens (Human Leucocyte Antigens), expressed, in particular, by the cells of graft vascular endothelium. This review describes the mechanisms of the development of humoral alloimmunity which are based on B-cell recognition of epitopes of donor HLA-molecules and affinity maturation of B-cell receptors in the germinal centers of peripheral lymphatic system. Monitoring of epitope load and cross-reactivity indicators to evaluate HLA-compatibility of donor and recipient plays an important role in the prevention of allograft humoral rejection.

The influenza virus is highly contagious diseases of people, birds and mammals. Approximately 250 000– 500 000 deaths are caused by influenza epidemics worldwide yearly, and the death number may be up to millions in a possible influenza pandemic. Vaccination is the most cost-effective way to reduce the considerable disease burden of seasonal influenza. Although seasonal influenza vaccines are effective, their performance in the elderly and immunocompromised individuals would benefit from improvement. Major problems related to the development and production of pandemic influenza vaccines are response time and production capacity as well as vaccine efficacy and safety. Reverse genetics techniques can speed up the generation of seed viruses and new mathematical modelling methods improve vaccine strain selection. Using vaccines based on recombinant proteins, we avoid the risks associated with the introduction of the virus into the body, even inactivated. In this paper, we have got a highly purified recombinant fusion protein composed of fragments of the hemagglutinin of influenza viruses A and B. As adjuvant we used components of flagellin. We used the most immunogenic and conserved areas of hemagglutinin H1, H3, H5 and B, which cause the formation of specific antibodies which can cross-react with homologous epitopes among the various strains of influenza A and B. Vaccine efficacy is increased by using multiple epitopes of various proteins. The aim of this study was to clone and express the hybrid recombinant protein Flu-Chim, containing immunogenic epitopes of influenza A/H1N1, A/H3N2, A/H5N1 and B fused with fragments of flagellin in Escherichia coli expression system and its subsequent purification. During the study was created high-yield E. coli strain, which produces the recombinant protein Flu-Chim, selected the optimal protocol of induction of the gene encoding the protein. The protein was purified using metal affinity chromatography. The purity of the final preparation reached 98%. In the future, we are going to study the immunogenic properties of the protein and use it as a component of the candidate vaccine against influenza.

Введение. Коронавирус SARS-CoV-2 является новым вирусом, обладающим способностью осуществлять трансмиссию воздушно-капельным путем, вызывая тяжелое течение атипичной пневмонии, нередко сочетающейся с коагулопатиями. Роль структурных белков коронавируса в их патогенезе неизвестна. Цель исследования: с помощью биоинформационного анализа выявить в структурных белках коронавируса SARS-CoV-2 последовательности, гомологичные белкам системы гемостаза, и рассмотреть возможные сценарии их участия в патогенезе коагулопатий при COVID-19, а также объяснить существование вирусостатического эффекта гепарина. Материалы и методы. Для компьютерного анализа были использованы доступные в Интернете базы данных первичных структур белков коронавирусов и их рецепторов, а также поверхностных белков других вирусов, белков системы гемостаза и иммунной системы. Сравнивали аминокислотный состав белков и распределение оснόвных аминокислот (аргинина и лизина) в их первичных последовательностях. С целью выявления пептидного (иммуноэпитопного) родства структурных белков коронавирусов с белками системы гемостаза человека был выполнен поиск гомологичных последовательностей в их белках. Результаты. В структурных белках коронавируса SARS-CoV-2 выявлено множество последовательностей, гомологичных белкам системы гемостаза и иммунной системы. В отличие от коронавирусов SARS-CoV и MERS-CoV, S1-субъединица S-белка коронавируса SARS-CoV-2 имеет положительную полярность. Заключение. Множество последовательностей в структурных белках коронавируса SARS-CoV-2, гомологичных белкам системы гемостаза, потенциально способны вы- зывать различные сценарии патогенеза коагулопатий. Положительная полярность S1-субъединицы S-белка коронавируса SARS-CoV-2 позволяет объяснить неспецифическое взаимодействие ее с гепарином и его вирусостатический (неантикоагулянтный) эффект., Background. The coronavirus SARS-CoV-2 is a new virus capable of human-human transmission and inducing a severe atypical pneumonia often associated with coagulopathy. A role of SARS-CoV-2 structural proteins in coagulopathy pathogenesis is unknown. Objectives: to use a bioinformation analysis to identify SARS-CoV-2 sequences in the structural proteins that are homologous to hemostasis system proteins, regard their possible participation in coagulopathy pathogenesis and explain the antiviral effect of heparin. Materials / Methods. For computer analysis, Internet databases were used of the primary structures of coronavirus proteins and their receptors, as well as surface proteins of other viruses, proteins of hemostasis and immune systems. The amino acid composition of proteins and the distribution of basic amino acids (arginine and lysine) in their primary sequences were compared. For detection of peptide (immunoepitopic) relationship of coronaviruses structural proteins with human hemostasis proteins, a search for homologous sequences in their proteins was performed. Results. Many sequences have been identified in structural proteins of SARS-CoV-2 coronavirus that are homologous to the proteins of hemostasis and immune systems. In contrast with SARS-CoV and MERS-CoV coronaviruses, the S1-subunit of SARS-CoV-2 coronavirus S-protein has a positive polarity. Conclusions. Many sequences in SARS-CoV-2 structural proteins that homologous to hemostasis system proteins are potentially responsible for coagulopathy pathogenesis. The positive polarity of the S1-subunit of SARS-CoV-2 S-protein explains its nonspecific interaction with heparin and its virostatic (non-anticoagulant) effect., Тромбоз, гемостаз и реология, Выпуск 4 2020

Одним из интенсивно развивающихся направлений в области разработки вакцин является конструирование искусственных или химерных белков содержащих фрагменты антигенов, вызывающих образование протективного иммунного ответа. В области разработки вакцины против ВИЧ-инфекции приоритетным считается направление по созданию иммуногенов, способных обеспечить индукцию антител, нейтрализующих широкий спектр первичных изолятов ВИЧ-1. Первым этапом оценки любого иммуногена является изучение его безвредности для организма и иммунохимических свойств. В данной работе приведены результаты исследования иммунохимических и иммуногенных свойств химерного белка включающего фрагмент полипептида B. subtilis и участок gp41 ВИЧ-1 MPER. Было показано, что эпитопы широконейтрализующих антител, входящих в этот регион, распознаются соответствующими моноклональными антителами. Иммунизация лабораторных животных очищенным химерным белком показала, что он не токсичен для животных и обладает высокой иммуногенностью. Полученный иммуноген будет использован в дальнейших исследованиях, направленных на индукцию широконейтрализующих антител., One of the intensively developing areas in the field of vaccine development is the construction of artificial or chimeric proteins containing fragments of antigens that cause the formation of protective immune response. In the field of developing a vaccine against HIV infection, the priority is to develop immunogens capable to provide induction of antibodies neutralizing a wide range of primary HIV-1 isolates. The first step in evaluating any immunogen is to study its harmlessness to the body and its immunochemical properties. In this paper, we present the results of a study of the immunochemical and immunogenic properties of a chimeric protein comprising a B. subtilis polypeptide fragment and an HIV-1 MPER gp41 site. It has been shown that the epitopes of broadly neutralizing antibodies included into this region are recognized by the corresponding monoclonal antibodies. Immunization of laboratory animals with purified chimeric protein showed that it is not toxic to animals and has high immunogenicity. The resulting immunogen will be used in further studies aimed at the induction of broadly neutralizing antibodies., Международный научно-исследовательский журнал, №08(62) (2017)

This study has shown that intravenous normal human immunoglobulin (IVIG), when included into combined therapy of acute epiglottitis, exerts positive effect upon clinical course of the disease and contributes to normalisation of immune status. Due to IVIG therapy, an increase in IgA and sIgA concentrations is observed in laryngopharynx secretions. Amounts and affinity of serum antibodies to common bacterial antigenic determinant are increased in blood, as well as opsonizing properties of blood serum. Moreover, a higher phagocytic and bactericidal activity of neutrophils is observed with such treatment. Inflammatory as well as degenerative and destructive processes in epiglottis seem to be preventable under the influence of IVIG therapy.

The problem of the human antithyroid peroxidase autoantibodies epitopes heterogeneity diagnosed in case of Graves' disease and Hashimoto's thyroiditis has been researched using monoclonal antibodies to thyroid peroxidase. It was shown, that in the competition for the binding sites of thyroid peroxidase and autoantibodies taken from patients with Graves' disease and Hashimoto's thyroiditis sera participate 8 mAb to epitopes 1, 70, 82, 88, 2, 3, 77 and 79. The maxima of the binding inhibition has been marked for the conformation epitope mAb 3: in case of Graves' disease it amounts to 60.3 ± 12.7%, in case of Hashimoto's thyroiditis – 61.8 ± 32.2%. Moreover the level of the binding inhibition did not depend on the concentration of Ab to thyroid peroxidase in the sera of patient with Graves' as opposed to the serum of patients with Hashimoto's thyroiditis. Autoantibodies in the serum of the patientswith Hashimoto's thyroiditis inhibited the binding of mAb to epitope 77 much more effectively, than in the serum of the patients with: 36.3 ± 17.2 and 54.3 ± 9.6% (p ≤ 0.05).The obtained results represented the specific reaction of the autoantibodies to the certain thyroid peroxidase molecular patterns which corresponds to the literature data. It is possible to assume that the further research of the competitive interactions with other autoantibodies to monoclonal antibodies, not included in this trial, and widening of the different thyroid diseased patients' serum palette can expose new immunodominant thyroid peroxidase molecular patterns, forming antibodies for different diseases, and enable the development of diagnostics and control of the thyroid functions and applied therapy.

We studied the specificity of excretory-secretory and somatic antigens of Fasciola hepatica and Paramphistomum ichikawai using enzyme-linked immunosorbent analysis and indirect hemagglutination reaction. Antigens of Echinococcus granulosus (ESAgE), Toxocara canis (ESAgT) and Strongyloides papillosus (ESAgS) were selected for the study of the specificity of fasciola and parafistomum immune reagents on account of the presence of their common antigenic epitopes. Material for the preparation of diagnostic kits (antigenes primarily processed, purified by centrifugation) Fasciola hepatica and Paramphistomum ichikawai were kept frozen in plastic containers «Ependorf» (5, 10 ml) at -6-8°C. At the same time reducing of antigen activity was not observed for 15-18 months. Erythrocyte diagnosticuma stored at +4°C showed equal sensitivity in the RIHA for 10 months since the moment they had been prepared. In 14-16 months their sensitivity (compared with the native and positive for fascioliasis and paramfistomatozy blood sera) was reduced by 25-50%. The results of experimental investigation (performed ELISA and RIHA with the above said controls in homologous and heterologous systems) show that immune sera to Fasciola hepatica (working titer 1:10240) and Paramphistomum ichikawai (1:5120) with the corresponding diagnosticuma (ESAgF and ESAgP) are positive in the maximum titers, when using somatic trematode antigens (SomAgF and SomAgP) in the homologous system we obtained the data confirming insufficient (scanty) specificity of these antigenic immunoreagents (1:1280 and 1:640 for ELISA, 1:640 and 1:320 in RIHA respectively).

S u m m a r y Pigs that survive after infection with African swine fever virus are resistant to reinfection with seroimmunotype-homologous virulent isolates, indicating an immune protection development. Nevertheless, the points regarding the protective importance of various immune mechanisms at African swine fever still remain controversial. Peripheral blood leukocyte cultures prepared from both intact or vaccinated pigs were used as models of implemented virus-specific reactions in vivo. The maximum amount of ASF virus was determined in the cultures with adherent cells from intact or immunized gilt, non-adherent white blood cells and the serum of an intact animal. Replacement of non-adherent cells from intact gilt by those from the immunized one led to a significant decrease in ASF virus titres. It was shown that combination of A-cells from intact or immunized gilt, non-adherent cells from the intact animal and the serum from immunized animal limited the viral propagation more strictly, under the replacement of non-adherent cells from the intact gilt by those from the immunized animal at the most. The results determine the role of cellular and humoral immunity in limiting African swine fever virus replication. The protection mechanisms mediated by cytotoxic T lymphocytes and antibody-mediated cellular anti-effectors are found to have an integrated effect, suggesting their targeting against different epitopes.

The novel viral vectors PVX-CP AltMV and PVXdt-CP AltMV are superexpressors of the capsid protein (CP). These viral vectors were constructed on the basis of the potato virus X (PVX) genome and Alternanthera mosaic virus (AltMV) CP gene. The expression, based on the hybrid viral vectors, is genetically safe, since the systemic transport and formation of infective viral particles are blocked. CP AltMV can self-assemble into virus-like particles (VLPs) in the absence of genomic RNA. The vectors can be used for the presentation of foreign peptides (including epitopes of human pathogens) on the surface of the VLP. The N-terminal extracellular domain (M2e) of the influenza virus A M2 protein and its truncated variant (ΔM2e) were used as model heterologous peptides for the construction of the chimeric CP AltMV. Chimeric CP AltMV retains its ability to self-assemble into VLP. The epitopes of the M2 influenza virus protein were not eliminated during the process of accumulation, polymerization and purification of chimeric VLP AltMV, providing evidence of the stability of chimeric VLP with C-terminal heterologous epitopes. It appears that VLP produced by the vectors PVX-CP AltMV and PVXdt-CP AltMV can be used in the field of biotechnology for the presentation of the epitopes of vaccine proteins on their surfaces. The chimeric VLP AltMV with the presented foreign epitopes can be used as candidate vaccines.