Design and study of immunogenicity of virus vaccine against viral pneumoenteritis of calves

The immunogenicity of a virus vaccine against viral pneumoenteritis in young cattle was studied in laboratory animals. The results of the selection of optimal vaccine strains to study the effects of different inactivants on infectious rhinotracheitis virus, viral diarrhea, parainfluenza-3, respiratory syncytial virus, rotavirus and coronavirus are presented. The accumulation of avirulent vaccine virus strains was carried out using established virological methods on transplanted cell cultures of MDBC (calf kidney cells) and SPEV (fetal pig kidney cells). Theotropine and formalin were used as inactivating agents to develop inactivation regimes for vaccine strains - components of the experimental vaccine. The antigenic activity of attenuated strains of infectious rhinotracheitis virus, viral diarrhea, parainfluenza-3, respiratory syncytial virus, rotavirus and coronavirus on white mice and calves and the level of specific antibodies in the sera of guinea pigs immunized with vaccines using different adjuvants were studied. Avirulent strains of viruses were used in the design of a new virus vaccine against viral pneumoenteritis: infectious rhinotracheitis (IBR-VBF-VHAVM No. 404); diarrhea (VDVBF-VHAVM No. 406); parainfluenza-3 (PG-VBF-VHAVM No. 403); respiratory syncytial virus (RSV-VBF-VHAVM No. 405); rotavirus (RTV-VBF-VHAVM No. 401) and coronavirus (CV-VBFVHAVM No. 407). The selected vaccine strains are non-reactive and induce active production of antiviral antibodies in sufficiently high titres in both laboratory animals (white mice) and farm animals (cattle). The most effective inactivating agents are 0.1% theotropine and 0.2% formalin. Two types of oil-based adjuvants, ISA 15 and ISA 25, were used to select the optimal adjuvants for the design of the virus vaccine. Adjuvant ISA 15 was used at 15% of the antigen quantity, ISA 25 at 25%. The adjuvant IZA 15 at a concentration of 15% is the optimum adjuvant for the preparation of an experimental virus vaccine against viral pneumoenteritis in young cattle.

The Impact of Mutations on the Pathogenic and Antigenic Activity of SARS-CoV-2 during the First Wave of the COVID-19 Pandemic: A Comprehensive Immunoinformatics Analysis

An in-depth analysis of first-wave SARS-CoV-2 genome is required to identify various mutations that significantly affect viral fitness. In the present study, we performed a comprehensive in silico mutational analysis of 3C-like protease (3CLpro), RNA-dependent RNA polymerase (RdRp), and spike (S) proteins with the aim of gaining important insights into first-wave virus mutations and their functional and structural impact on SARS-CoV-2 proteins. Our integrated analysis gathered 6000 SARS-CoV-2 sequences and identified 92 mutations in S, 37 in RdRp, and 11 in 3CLpro regions. The impact of these mutations was also investigated using various in silico approaches. Among these, 32 mutations in S, 15 in RdRp, and 3 in 3CLpro proteins were found to be deleterious in nature and could alter the structural and functional behavior of the encoded proteins. The D614G mutation in spike and the P323Lmutation in RdRp are the globally dominant variants with a high frequency. Most of the identified mutations were also found in the binding moiety of the viral proteins which determine their critical involvement in host–pathogen interactions and may represent drug targets. Furthermore, potential CD4+ and CD8+ T cell epitopes were predicted, and their overlap with genetic variations was explored. This study also highlights several hot spots in which HLA and drug selective pressure overlap. The findings of the current study may allow a better understanding of COVID-19 diagnostics, vaccines, and therapeutics.

Effects of Lower Temperature on Expression and Biochemical Characteristics of HCV NS3 Antigen Recombinant Protein

The nonstructural antigen protein 3 of the hepatitis C virus (HCV NS3), commonly-used for HCV ELISA diagnosis, possesses protease and helicase activities. To prevent auto-degradation, a truncated NS3 protein was designed by removing the protease domain. Firstly, it was overexpressed in E. coli by IPTG induction under two different temperatures (25 and 37 °C), and purified using affinity chromatography to attain homogeneity above 90%. The molecular mass of purified protein was determined to be approx. 55 kDa. While lowering the temperature from 37 to 25 °C, the yield of the soluble fraction of HCV NS3 was increased from 4.15 to 11.1 mgL−1 culture, which also improved the antigenic activity and specificity. The protein stability was investigated after long-term storage (for 6 months at −20 °C) revealed no loss of activity, specificity, or antigenic efficacy. A thermal stability study on both freshly produced and stored HCV NS3 fractions at both temperatures showed that the unfolding curve profile properly obey the three-state unfolding mechanism. In the first transition phase, the midpoints of the thermal denaturation of fresh NS3 produced at 37 °C and 25 °C, and that produced after long-term storage at 37 °C and 25 °C, were 59.7 °C, 59.1 °C, 55.5 °C, and 57.8 °C, respectively. Microplates coated with the fresh NS3 produced at 25 °C or at 37 °C that were used for the HCV ELISA test and the diagnosis outcome were compared with two commercial kits—Abbott HCV EIA 2.0 and Ortho HCV EIA 3.0. Results indicated that the specificity of the HCV NS3 produced fresh at 25 °C was higher than that of the fresh one at 37 °C, hence showing potential for application in HCV ELISA diagnosis.

Phytochemical, Nutritional and Pharmacological Potentialities of Amaranthus spinosus Linn. : A review

Amaranthus spinosus has long been cultivated in tropical and subtropical areas of the world, especially in South Asia. It is well accepted by the people for its nutritional, pharmacological, phytochemical, and therapeutic functions in the human body. Tender stems, leaves, shoots, grains and sometimes the whole part of A. spinosus are eaten by humans or fed to farm animals, which contain carbohydrates, proteins, fats, fibers, vitamins, minerals and many other phytochemicals. This review aims to represent the nutritional and pharmacological activities of A. spinosus. To have a better understanding, we have discussed the nutritional status of A. spinosus, its available phytochemicals and their functional properties. Further, we demonstrated the potentiality of A. spinosus in various disease condition by discussing its functional activities, which includes antioxidant, antidiabetic, immuno-modulatory, hematological, gastrointestinal, anti-inflammatory, diuretic, antimicrobial, antimalarial, anti-ulcer, antipyretic, and antigenic activity. The availability of various important phytochemicals along with their functional properties make Amaranthus spinosus valuable for pharmaceuticals and nutraceuticals industry.

Dissociated forms of moraxella isolated from the affected eyes of cattle

The dissociation phenomenon of epizootic cultures of Moraxella was studied. The study was conducted in economic entities of Almaty region of the Republic of Kazakhstan for 233 heads of cattle with clinical signs of keratoconjunctivitis. Isolation of the causative agent of Moraxella was performed by bacteriological washes from the conjunctival sacs of the eyes of animals. The laboratory study was carried out according to the approved methodological guidelines. It was found that bacteria of the genus Moraxella dissociate when grown on a solid nutrient medium for more than 6 hours in a thermostat at 37 °C. The bacteria were studied by the following methods: staining according to White-Wilson, thermoagglutination and acriflavine assay. When evaluating the grown colonies according to White-Wilson, the optimal dilution for crystal violet was found to be 1 : 2000, and for gentian violet stain 1 : 1000. In this case, the colonies in the S-form have a dark purple color with a metallic tint, and the dissociated colonies in the R-form do not stain. In the presence of dissociated cells, precipitation (thermoagglutination), sediment formation and clearing of the supernatant fluid at 90 °C for 30 minutes were noted. The suspension of undissociated colonies remained cloudy. When weighing microbial cells isolated by a bacterial loop from individual grown colonies in a solution of acriflavine, dissociated bacteria stick together to form conglomerates. When studying the antigenic activity of the S-, R- forms of Moraxella, it was revealed that the activity of the S-antigen significantly exceeded that of the R-forms. Data on the dissociation of Moraxella cultures can be used for the development of diagnostic and prophylactic drugs against moraxellosis in cattle.

Determination of the optimal dose of low-agglutinogenic vaccine (LAV) for laboratory animals

Currently, live vaccines are mainly used to prevent brucellosis in animals. The effectiveness of such vaccines is a time-tested fact. However, live vaccines have many disadvantages, they can cause abortions in vaccinated animals, some vaccine strains migrate to unvaccinated animals, and pose an epidemiological danger. In addition, there is a problem of postvaccinal antibodies, which complicates the differential diagnosis of immunized and sick animals. When receiving a weakly agglutinogenic vaccine, it is important to choose a specific protective antigen, since the antigenic set of any bacterium, including brucella, is very large, and not all antigens are of equal importance in the formation of immunity. Studies were conducted on rabbits and guinea pigs that react negatively to brucellosis. Before and after vaccination, the antigenic activity of the test vaccine and the level of antigen-binding lymphocytes with a receptor for the protective brucella antigen were determined in dynamics. To detect the antigenic activity of LAV, a red blood cell diagnostic was prepared, which was obtained by sorption of the protective brucella antigen on tanized red blood cells. Based on the results of serological and bacteriological studies, it was found that the LAV at a dose of 0.1 mg of antigen is optimal. A dynamic increase in serological conversion in vaccinated rabbits and guinea pigs was observed with the introduction of each dose of the vaccine. Depending on the dose range, the highest peak of seroconversion was observed in guinea pigs on day 30 and in rabbits on day 15 of the study. Thus, the optimal vaccination dose of brucellosis weakly agglutinogenic vaccine with a single administration should be considered: for guinea pigs - 0.1 mg, and for rabbits-0.2 mg. Consequently, the administered dose of the test vaccine affected the induction of agglutinins and depended on the injected dose of the drug, which was reflected in the results of seroconversion. Maximum seroconversion was observed in guinea pigs on day 30, in rabbits on day 15 after immunization.

ASSESSMENT OF THE EFFECTIVENESS OF A UNIVERSAL VACCINE AGAINST AGRICULTURAL ANIMAL CHLAMIDIOSIS ON RABBITS

The article presents data on laboratory tests of a universal vaccine against chlamydia of farm animals for sterility, safety, antigenic activity and immunogenicity. The sterility of the new vaccine preparation was evaluated on nutrient media (MPA, MPB, MPPB and Saburo), the vaccine was harmless according to the results of bioassays on laboratory white mice and guinea pigs. The vaccine was found to be sterile and harmless to laboratory animals. Evaluation of antigenic activity was car-ried out on rabbits, the study lasted 195 days, the results were taken into account on the basis of data obtained during systematic serological studies of blood serum immunized with rabbits. It was found that the vaccine stimulates the immune system of laboratory animals to produce complemen-tary chlamydial antibodies. After 6.5 months after the administration of the drug, the titers of chla-mydial antibodies remained above the protective titer and were equal on average 1:60. Evaluation of the immunogenicity of the vaccine was carried out in an acute experiment on rabbits (females). Dur-ing the experiment, it was possible to establish the ability of the vaccine to induce the production of immunity in laboratory animals that can overcome chlamydial infection. Healthy rabbits were ob-tained from rabbits vaccinated and infected at the 3rd week of pregnancy, while mass abortions, stillbirths and the birth of non-viable offspring were noted in the control groups. According to the results of post-mortem dissection of animals from the experimental and control groups, it was found that vaccinated and further infected animals did not reveal any pathological changes in the internal organs, in contrast to the animals from the control groups.

Comparative evaluation of antigenic activity of means of immune prevention of anaerobic enterotoxemia of calves

The study of the antigenic activity of vaccines used against anaerobic enterotoxemia of calves was carried out. The level of antibodies during immunization with the vaccines: «Polyvalent toxoid Clostridium perfringens against anaerobic enterotoxemia of calves» and the associated vaccine against clostridiosis «Klostbovak-8» – was comparable. Credits to all types of the pathogen was protective in the application of the toxoid. At 40–50 days of age, the level of antibodies was significantly higher when using polyvalent toxoid. No antibodies were detected in the control group.

Retraction: Chemical synthesis and antigenic activity of a phosphatidylinositol mannoside epitope from Mycobacterium tuberculosis

Retraction of ‘Chemical synthesis and antigenic activity of a phosphatidylinositol mannoside epitope from Mycobacterium tuberculosis’ by Shi-Yuan Zhao et al., Chem. Commun., 2020, 56, 14067–14070, DOI: 10.1039/D0CC05573E.

HYDROLYTIC REGULATION OF COMPONENT PROPERTIES

. The article provides an assessment of the dairy farming need in the Russian Federation and the Republic of Belarus in calves feed. The main global trends aimed at providing young animals with high-quality food means are considered. Various variants of directed hydrolysis of calf milk replacer (CMR) protein components intended for feeding young animals in the first months of life are analyzed. The possibilities of reducing the soy proteins antigenic activity, which are widely used at present in the CMR formulations for feeding young farm animals, are discussed. The results of experimental work and patents are presented, which describe the most widely used approaches to the production of enzymatic hydrolysates of proteins with desired properties, as well as the assessment of their biological activity and immunochemical properties. The issues of using various enzyme preparations of bacterial, fungal and animal origin for hydrolysis of colostrum proteins and plant sources of protein raw materials for the CMR production are considered.