[Immunogenicity and safety of vaccine preparations based on circulating Bordetella pertussis strains].

AIM: Study specific activity and safety ofvaccine preparations based on circulating B. pertussis strains with currently predominating allele variants of pertussis toxin (ptxA1) and pertactin (prn2) genes. MATERIALS AND METHODS: B. pertussis strains isolated from pertussis patients in Moscow in 2001-2010 were grown in dense and liquid media. The content of separate antigens in B. pertussis strains was determined by EIA. Immunogenicity and safety of the preparations was determined in F1(CBAxC57B16) line mice. RESULTS: All the studied circulating B. pertussis strains expressed pertussis toxin (PT), filamentous hemagglutinin (FHA) and agglutinogens corresponding to the serovar. Whole-cell and acellular pertussis vaccines were prepared based on the circulating strains, and a highly productive recently isolated toxigenic B.pertussis strain that could be used for production ofpertussis vaccines was selected as a result of studies ofimmunogenic, toxic and sensibilizing properties. CONCLUSION: Vaccine preparations based on a B. pertussis strain adapted to growth in liquid media with pertussis toxin and pertactin ptxAl1 - prn2 gene allele variation characteristic for contemporary population are specifically active and safe.

[Immunobiological properties of Bordetella pertussis lipopolysaccharide in the acellular pertussis vaccine].

AIM: Study of Bordetella pertussis lipopolysaccharide (LPS) immunobiological properties in the acellular pertussis vaccine. MATERIALS AND METHODS: Experimental series of acellular pertussis vaccines (APV), lyophilized LPS were used. Antibody titers against LPS in mice sera were evaluated by using EIA with peroxidase conjugate of anti-species antibodies against mice IgG. LPS activity in B. pertussis antigen complex preparations was determined in quantitative chromogenic LAL-test by end point. APV protective activity was determined in mice test during intracerebral infection by B. pertussis strain No. 18323 virulent culture. APV safety was determined in the mice body weight change test. RESULTS: The presence of LPS in APV was shown in immune electrophoresis with purified B. pertussis LPS preparation as a control. Formalin treatment changes immunochemical properties of APV LPS that lead to the shift of precipitation bands with pertussis agglutinating sera from the start zone into cathode. The quantity of LPS in pertussis culture supernatants was on average 49050 +/- 6774 endotoxin units per ml (EU/ml). In APV preparations the quantity of LPS was on average 906 +/- 90 EU/ml, i.e. decreased by more than 50 times. An increase of antibody titers against B. pertussis LPS in mice sera after the APV immunization was shown in EIA, which gives evidence of its presence in immunogenic form in the complex preparations. The preclinical studies carried out show protective activity and specific safety of the experimental APV series. CONCLUSION: Formalin-neutralized APV preparation is a complex of protein antigens in association with LPS. Formalin treatment results in modification of LPS molecule that retains antigenic properties but is significantly less toxic.

[Preclinical studies of an adsorbed diphtheria-tetanus-pertussis vaccine (ADTP-vaccine) with acellular pertussis component].

AIM: Evaluate standardness of antigenic composition of pertussis component, completeness of sorption of pertussis, diphtheria and tetanus components, specific activity and safety of experimental series ofADTP-vaccine with acellular pertussis component (ADTaP-vaccine). MATERIALS AND METHODS: The content of separate antigens (pertussis toxin, filamentous hemagglutinin and agglutinogens 1, 2, 3) in samples of acellular pertussis component of ADTaP-vaccine and completeness of sorption of pertussis component of ADTaP-vaccine were evaluated by using enzyme immunoassay. Completeness of sorption of diphtheria and tetanus components were determined in flocculation reaction and antitoxin-binding reactions, respectively. Protective activity ofADTaP-vaccine was studied in model ofmeningoencephalitis development in mice infected with Bordetella pertussis (strain 18323) neurotropic virulent culture, protective activity oftetanus component - by survival of mice after administration of tetanus toxin, protective activity of diphtheria component - by survival of guinea pigs after administration of diphtheria toxin. Safety of preparations was evaluated in tests of acute and chronic toxicity with carrying out pathomorphologic studies including immature animals. RESULTS: All the studied experimental series ofADTaP-vaccine were standard by content of separate antigens of pertussis microbe. All the ADTaP-vaccine components were completely sorbed on aluminium hydroxide gel. By protective activity ADTaP preparations satisfied the WHO requirements. The preparations were non-toxic in acute and chronic toxicity and did not induce pathomorphologic changes including immature animals. CONCLUSION: Experimental samples of ADTaP-vaccine by specific activity and safety satisfied WHO requirements.

[Medical and biological safety assessment of genetically modified soybean event MON 89788. Report 2. Genotoxicologic, immunologic and allergologic examinations].

There are presented the results of genotoxicologic, immunologic and allergologic examinations which were conducted within the framework of integrated medical and biological assessment of genetically modified second generation soybean event MON 89788. Analysis of damages of DNA and structural chromosome aberrations, assessment of the allergenic potential and immunoreactive properties has not confirmed any genotoxic, allergenic and immunotoxic effect of soybean event MON 89788.

[Medical and biological safety assessment of genetically modified maize event MIR604].

There are presented the results of genotoxicologic, immunologic and allergologic examinations which were conducted within the framework of integrated medical and biological assessment of genetically modified rootworm Diabrotica spp.-protected maize event MIR604. Analysis of damages of DNA and structural chromosome aberrations, assessment of the allergenic potential and immunoreactive properties has not confirmed any genotoxic, allergenic and immunotoxic effect of maize event MIR604.

[Antigenic composition and serologic characteristics of domestic acellular pertussis vaccine].

AIM: To assess antigenic composition consistency and serological characteristics of domestic acellular pertussis vaccine. MATERIALS AND METHODS: Amount of pertussis toxin, filamentous hemagglutinin, agglutinogens types 1, 2, and 3 in experimental batches of vaccine was measured by enzyme immunoassay. Levels of antibodies to aforementioned antigens as well as to lipopolysaccbaride in serum samples obtained from patients with pertussis and healthy vaccinated children were measured by the same method. The amount of lypopolysaccharide was determined by LAL test. RESULTS: Studied batches of vaccine were standard on amount of all protein antigens as well as lipopolysaccharide. Spectrum of antibodies to vaccine components in serum samples from patients with pertussis and healthy vaccinated children included antibodies to individual antigens: pertussis toxin, filamentous hemagglutinin, lipopolysaccharide, agglutinogens types 1, 2, and 3. CONCLUSION: Developed technology for manufacturing acellular pertussis vaccine allows to consistently produce preparations with standard amount of all components. Vaccine components interact with antibodies to wide spectrum of B. pertussis antigens.

[Dynamics of changes in pathogenic characteristics of Bordetella pertussis strains].

AIM: To study pathogenic characteristics of B. pertussis strains isolated from patients during different periods of pertussis infection epidemic process. MATERIALS AND METHODS: Strains of B. pertussis isolated in Moscow during 1967 - 1971, 1980 - 1985, and 2001 - 2005 were studied. Nutrient media: Bordet-Gengou blood agar, casein-charcoal agar. ANIMALS: mice - F1 hybrids (CBA x C57BL6). Pathogenic characteristics of strains were studied by assessment of virulence (LD50), leukocytosis-stimulating (LS units) and histamine-sensitizing (HSD50) activities of cultures. Genotyping was performed using standard equipment and reagents for DNA isolation, amplification, sequencing and detection of results. RESULTS: On the sample of 164 strains, pathogenic and genotypic characteristics of B. pertussis populations circulated during 1967 - 1971, 1980 - 1985, and 2001 - 2005. Majority of B. pertussis strains isolated in 1967 - 1971 and strains circulated during current phase of epidemic process were virulent (80.75% and 81.8% respectively) and had significant leukocytosis-stimulating and histamine-sensitizing activity, whereas strains isolated from patients with pertussis in 1980 - 1985 characterized by lower virulence and toxicity. Genotyping showed strains carrying "non-vaccine" allele ptxA1, which emerged in the middle of 1970s, totally displaced strains with "vaccine" alleles ptxA2 and ptxA4. CONCLUSION: Adaptive changes of B. pertussis driven by increased vaccination coverage involve both ptxA gene and pathogenic characteristics of infectious agent in the range of genotypically homogenous population with domination of strains, which have high levels of virulence and toxicity.

[Acellular pertussis vaccine].

Protective, immunogenic, toxic, and sensitizing properties of acellular pertussis vaccine (aPV) developed according to original technology were studied, aPV had marked protective activity which lasted more than 2 years. Sera of mice immunized by aPV also possess protective properties, and they were more prominent than in sera of mice immunized by pertussis bacteria suspension (PS). Immune sera to aPV neutralized cytopathogenic effect of pertussis toxin (PT) on ovarian Chinese hamster cells in 1:250 dilution, whereas neutralizing activity of sera to PS was very low. Level of antibodies to PT was higher in rabbits immunized, according to schedules and dosage recommended for children, by aPV than by PS. High immunogenicity of aPV was proved also by levels of IgG to PT in sera of mice immunized three times by aPV in human dosage. During experiments on mice and guinea pigs aPV had mild toxicity, did not induce autoimmune process, did not have anaphylactogenic properties compared with bacterial suspension characterized by high anaphylactogenic activity. Histamine-sensitizing abilityof aPVwas 40 times lower than that of PS. Assessment of pyrogenic properties of aPV and PS performed on rabbits showed that aPV was 1,000 times less pyrogenic than PS. Obtained results demonstrate high protective and immunogenic properties of domestic acellular pertussis vaccine and its low toxic and sensitizing characteristics.

[Modern strains of Bordetella pertussis: immunobiological properties and vaccine improvement].

Strains of B. pertussis isolated from patients in Moscow in 2001-2005 as well as strains included in locally produced diphtheria-tetanus-whole cell pertussis (DTP) vaccine were studied. Nucleotide sequences in genes of pertactin and S1-subunit of pertussis toxin of isolated strains, their immunobiological properties and opportunity to use for producing of the acellular pertussis vaccine were determined. Genes of pertactin and S1-subunit of pertussis toxin in the isolated wild strains differed from the same genes in strains included in the local DTP vaccine. Majority of the isolated strains belonged to serotype 1.0.3 and were markedly virulent.

[Protective activity of adsorbed D(a)PT vaccine with the acellular pertussis component and polyoxydonium].

The introduction of the immunomodulator polyoxidonium in an amount of 0.5 Mg/ml into adsorbed D(a)PT vaccine with the acellular pertussis component leads to the preservation of the protective activity of the pertusis component, diphtheria and tetanus toxoids, as well to the 4-time decrease of the content of adsorbent (aluminium hydroxide) from 2 to 0.5 mg/ml.

[New acellular pertussis vaccine, containing glucosaminylmuramyldipeptide]. / Sozdanie novoi beskletochnoi kokliushnoi vaktsiny, vkliuchaiushchei gliukozaminilmuramildipeptid.

As shown in this work, the synthetic immunomodulator glucosaminylmuramyldipeptide (GMDP) can be included into acellular pertussis vaccine (APV). The optimal doses of GMDP, ranging from 0.001 to 0.0001 microg, have been found. These doses enhance the protective activity of APV, especially its low-active doses. GMDP decrease the manifestations of toxic, anaphylactogenic and pyrogenic properties of APV, which may lead to the decrease of the antigenic load of APV on the body of the vaccines and thus to lessening the side-effects of vaccination. GMDP has been shown to considerably increase, in comparison with common pertussis vaccine and APV, the percentage of phagocytizing leukocytes by day 14. The immunization of mice with APV with and without GMDP in doses of 0.01 and 0.001 microg leads to a change in T-lymphocyte/B-lymphocyte ratio in the population of spleen lymphocytes.

[Morphological alterations in animal organs after the injection of acellular pertussis vaccine with immunomodulator]. / Morfologicheskie izmeneniia v organakh zhivotnykh posle vvedeniia beskletochnoi kokliushnoi vaktsiny s immunomoduliatorom.

Toxic properties of acellular pertussis vaccine (APV) and morphological changes in white mice in response to intramuscular injection of APV (without or with immunomodulator glucosaminylmuramyl dipeptide-GMDP) were under study. APV used in these experiments was developed at the Mechnikov Research Institute for Vaccines and Sera (the Russian Acad. Med. Sci.) on the basis of Bordetella pertussis cultures in synthetic fluid culture media. In experiments on acute and chronic toxicity of APV (without GMDP) increased tissue immunity reactions in spleen, thymus, liver, lungs and intestinal wall was detected. There was no difference in immunomorphological reactions in mice receiving APV with different doses of GMDP, but some difference was observed in time dynamics of tissue immunity reactions. A small dose of GMDP should be preferred (0.0001 microgram) which results in gradual growth of tissue immunity reactions less pronounced toxic reactions caused be the APV injection.

[Humoral response to the injection of acellular Pertussis vaccine]. / Gumoral'nyi otvet na vvedenie beskletochnoi kokliushnoi vaktsiny.

The humoral response of mice and rabbits to the injection of whole-cell pertussis vaccine (PV) and acellular pertussis vaccine (APV), developed at the Mechnikov Research Institute for Vaccines and Sera (Russian Acad. Med. Sci.) in Moscow, was studied. In the sera of immunized animals antibodies to the antigenic complex were determined in the direct hemagglutination (DHA) test, specific antibodies to filamentous hemagglutinin (FHA) and pertussis toxin (PT)--in the enzyme immunoassay (EIA) and antibodies neutralizing PT in a cytopathogenic dose (CPD)--in neutralization test on Chinese hamster ovary (CHO) cells. In mice and rabbits immunized with APV the antibody titers determined in the DHA test were higher than those in the animals immunized with PV. Specific antibodies titers to FHA and PT in the sera of rabbits immunized with APV were also higher than those in the sera of rabbits immunized with PV. High dilutions of sera taken from the animals immunized with APC neutralized 4-16 doses of PT in the neutralization test on CHO cells. The most important result of this study was the detection of a more pronounced immune response in the animals immunized with APV in comparison with that induced by PV according to the results obtained in EIA and in the test of PT CPD neutralization on CHO cells.

[The action of pertussis vaccines and GMDP on the change in the enzymatic activity of macrophages from peritoneal exudate]. / Izuchenie deistviia kokliushnykh vaktsin i GMDP na izmenenie fermentativnoi aktivnosti makrofagov peritoneal'nogo ékssudata.

The influence of whole-cell and acellular pertussis vaccines, introduced both alone and in combination with N-acetylglucosaminylmuramyl-2-alanine-D-isoglutamine (GMDP) on the activity of two enzymes of peritoneal exudate macrophages (5'-nucleotidase and Na+K(+)-adenosine triphosphatase) was studied. The study revealed that both pertussis vaccines exhibited immunomodulating properties, these properties being most pronounced in whole-cell pertussis vaccine. The use of GMDP in combination with pertussis vaccines led to changes in the enzymatic activity of peritoneal exudate macrophages, which was indicative of a decrease in the immunomodulating action of pertussis preparations.

[A polyvalent complex of Bordetella pertussis antigens as the basis for an acellular pertussis vaccine]. / Polivalentnyi kompleks antigenov Bordetella pertussis kak osnova beskletochnoi kokliushnoi vaktsiny.

The immunogenic and protective properties of acellular pertussis vaccines, prepared on the basis of B. pertussis multicomponent protective complex and the preparation containing only pertussis toxin, were studied. The study revealed that multicomponent preparations containing pertussis toxin (PT), filamentous hemagglutinin, agglutinogens, pertactin and adenylate cyclase possessed more pronounced immunobiological and protective properties in comparison with the monovalent preparation of PT, which was indicative of the expediency of developing acellular pertussis vaccines on the basis of the polyvalent protective complex as minor protective antigens seemed to enhance the protective action of pertussis toxoid, the main protective antigen.

[The expression of Bordetella pertussis protective antigens during bacterial multiplication on a medium with a fixed chemical composition]. / Ekspressiia protektivnykh antigenov Bordetella pertussis v protsesse razmnozheniia bakterii v srede opredelennogo khimicheskogo sostava.

The possibility of obtaining native pertussis preparations with high immunobiological activity has been shown. To obtain such preparations, the use of B. pertussis selected strain, its growth under the conditions of static cultivation in a synthetic culture medium and the use of supernatants with the maximum content of protective antigens with the aim of obtaining protective complexes are necessary.

[A comparative analysis of the antigenic complexes isolated from synthetic and semisynthetic media for the cultivation of Bordetella pertussis]. / Sravnitel'nyi analiz antigennykh kompleksov, vydelennykh iz sinteticheskoi i polusinteticheskoi sred kul'tivirovaniia Bordetella pertussis.

Some physicochemical properties of B.pertussis antigenic complexes isolated from synthetic and semisynthetic culture media have been studied. The chemical composition of these complexes has been determined. Proteins, polypeptide subunits and lipopolysaccharide forming these complexes have been characterized. The presence of two main protective substances of B.pertussis has been revealed: fimbrial hemagglutinin and B.pertussis toxin. The influence of culture medium on the level of the synthesis of B.pertussis adenylate cyclase has been studied.

[The safety and protective properties of a new cell-free pertussis vaccine in animal trials]. / Issledovanie bezvrednosti i protektivnykh svoistv novoi beskletochnoi kokliushnoi vaktsiny v opytakh na zhivotnykh.

The preclinical trial of a new cell-free pertussis vaccine has been carried out with a view to its comparison with whole-cell pertussis vaccine in respect of the toxic and protective properties of the preparations under experimental conditions. The whole-cell pertussis vaccine is characterized by pronounced toxic action causing leukocytosis and histamine-sensitization, produces a negative effect on the detoxifying function of the liver and possesses sensitizing activity. The cell-free pertussis vaccine has pronounced protective activity. In animal experiments the supposed immunization dose of this vaccine has proved to be nontoxic.

[The use of monolaurates for removing endotoxins from preparations of cell-free pertussis vaccine]. / Ispol'zovanie monolauratov dlia udaleniia éndotoksinov iz preparatov beskletochnoi kokliushnoi vaktsiny.

The possibility of using monolaurates for removing endotoxin from acellular pertussis vaccines developed at the Laboratory of Immunomodulators, Mechnikov Research Institute for Vaccines and Sera (Moscow), has been studied. Monolaurates PEG-400 and PEG-600 obtained, respectively, from Fluka Chemie AG and Ferak GmbH (Germany) have been used. The use of monolaurate PEG-600 ensures the decrease of the toxicity of acellular pertussis vaccines by 2.34-6.3 times.