The immunogenicity of mono- and associated vaccines made from strains of opportunistic bacteria]

In experiments on white mice the immunogenic potency of two variants of combined vaccines prepared from strains of opportunistic bacteria was compared with that of monovaccines used as the components of the combined vaccines. All the vaccines under study were found highly immunogenic. Decrease of monovaccine share in the combined vaccine did not reduce the immunogenic potency to any of the strains. An 8- to 16-fold increase in the level of specific antibodies in the colostric lactosera of cows immunized with combined vaccines was observed, and the survival rate of newborn calves increased 3- to 4-fold.     

Experimental study of the immunological activity of a preparation made from the antigenic complexes of opportunistic microorganisms administered by different routes

The data obtained in the experimental study of the humoral factors of local and systemic immunity, as well as the morphofunctional changes of internal organs, after multiple subcutaneous and aerosol immunization with the combined preparation of Proteus, Staphylococcus, Klebsiella pneumoniae and Escherichia coli antigens (preparation nC-4) are presented. The subcutaneous and aerosol administration of preparation nC-4 has been found to induce an increase in the levels of antibodies to all components of the preparation in the blood serum and in respiratory tract secretions. The introduction of the preparation through the respiratory tract resulted in an earlier intensive accumulation of specific antibodies and IgA in respiratory tract secretions. The results of the quantitative cytological study of respiratory tract secretions and the morphofunctional changes of the lymphoid tissue associated with the lungs are indicative of an important role played by cell-mediated immunity factors in the formation of local postvaccinal immunity.     

The specific activity of a multicomponent vaccine made from the antigens of opportunistic microorganisms

Multicomponent vaccine prepared from the antigens of 4 representatives of opportunistic microflora possesses high specific activity. The passive hemagglutination (PHA) test with the use of associated diagnosticum showed that antibody titers in the sera of immunized rabbits increased 10- to 10(4)-fold in comparison with the titers observed prior to immunization. The PHA test with the use of the antigens contained in the vaccine revealed the accumulation of antibodies to each of the 4 components of the preparation in the blood sera of immunized rabbits. When stored at 4 degrees C, the vaccine was shown to retain its specific activity for 5 years (the term of observation).     

The effect of immunotherapy with cell-free vaccines made from the antigens of opportunistic microorganisms on the dynamics of DNA antibody formation]

The sera of patients subjected to immunotherapy with staphylococcal vaccine and with multicomponent vaccine (i.e. the mixture of the antigenic preparations of Staphylococcus aureus, Klebsiella pneumoniae, Proteus vulgaris, Escherichia coli) were studied by the method of the enzyme immunoassay on the basis of cattle spleen DNA. Immunotherapy with staphylococcal vaccine was given to patients with dermal diseases, chronic obstructive bronchitis and pulmonary abscess. Multicomponent vaccine was introduced to patients with the infectious allergic form of bronchial asthma, moderate or severe. Immunotherapy with both preparations under study was shown to produce no accumulation of antibodies to native and denatured DNA.     

Immunostimulant preparation made from the antigens of opportunistic microorganisms in the treatment of inflammatory lung diseases

The results of the trial of an immunostimulating preparation, consisting of Klebsiella pneumoniae, Proteus, Escherichia coli and Staphylococcus antigenic complexes, on 20 patients with acute pulmonary abscess and bronchiectasis are presented. The preparation was introduced subcutaneously in 5 injections. The preparation was found to have low reactogenicity, and in the course of immunotherapy the manifestations of systemic and local reactions became considerably less pronounced. Immunotherapy produced a good curative effect, objectively manifested by a decrease in coughing and in the amount of sputum gradually changing its character. After the fourth and fifth injections the patients no longer ejected purulent sputum. Fluoroscopic examination revealed a considerable decrease in the size of the pathological focus. The preparation stimulated immunological reactions, and immunization resulted in a considerable increase in the titer of antibodies to all components of the combined preparation, as well as in an increase in the number of functionally active T-lymphocytes, in the blood of the patients.     

The sensitivity to antibiotics and chloramine B of opportunistic microorganisms isolated from patients

Strains of staphylococci, klebsiella, proteins, blue pus bacillus and enterobacteria resistant not only to antibiotics but also to chloramine, a disinfectant, were isolated from the test material samples obtained from patients with different purulent-inflammatory processes. The following strains are revealed among the test microorganisms: sensitive simultaneously to antibiotics and chloramine; sensitive to antibiotics but resistant to chloramine; sensitive to chloramine but resistant to antibiotics; simultaneously resistant both to antibiotics and chloramine.     

Biochemical activity of opportunistic antibiotic and chloramine-sensitive and resistant microorganisms isolated from healthy and sick people

Activity of oxidation-reduction enzymes such as succinate dehydrogenase, peroxidase and catalase was studied in staphylococci isolated from healthy persons and patients as well as from the air and implements of medical institutions. The isolates were resistant either to antibiotics or to chloramine B or to the both. The results showed that development of resistance to antibiotics and chloramine B in the staphylococci was accompanied by a decrease in the activity of succinate dehydrogenase, peroxidase and catalase. In the strains resistant only to chloramine B the activity of the enzymes was practically at the same level as in the strains resistant only to antibiotics. In the strains resistant to both antibiotics and chloramine B, the activity of succinate dehydrogenase, peroxidase and catalase did not practically differ from that in the strains resistant either to antibiotics or to chloramine B.     

Phytoalexin activity in apples as an indication of their resistance to phytopathogenic microorganisms]

Phytoalexin activity of various apple varieties was measured during their storage at subcryoscopic (-2.3 degrees C) and supracryoscopic (-1.3 degrees C) temperatures. More resistant late winter apple varieties Renet Simitrenko and Renet Champagne showed higher phyto-alexin activity than the autumn-winter strain Calville Snowy. By the end of storage the phytoalexin activity decreased independently on the storage conditions. However, the apples that were kepat at supracryoscopic temperature retained a hight phytoalexin activity. The apples which were kept at -2.3 degrees C showed no phytoalexin activity.     

The relationship of the antigenic characteristics of the tick-borne encephalitis virus to the level of the protective activity of inactivated cultured vaccines]

As shown in this study, the immunization of animals with killed vaccines against tick-borne encephalitis (TBE) leads to the formation of specific immunity, depending on the antigenic structure of the vaccine strain and the test strains used for challenge. Vaccines obtained on the basis of the TBE virus strain of the Eastern antigenic variant induced the development of a wider spectrum of specific protective activity than vaccines obtained on the basis of the TBE virus strain of the Western antigenic variant.     

Targeting and expression of antigenic proteins in transgenic plants for production of edible oral vaccines

Summary Exploiting plants as biological bioreactors for production and delivery of edible oral subunit vaccines is a promising application of biotechnology. Efforts to enhance expression levels of transgenes coding for antigenic proteins by exploiting promoters, targeting sequences, and enhancer elements have produced rather low quantities of the antigen in plant tissues, but enough to induce immune responses in feeding studies. This review will cover components of various gene constructs used in developing plant-based vaccines against a myriad of viral and bacterial diseases. Specifically, it will focus on sequences that are involved in targeting the antigen to mucosal tissues of the intestinal tract, thus enhancing the immunogenicity of the plant-based vaccine as well as those components that result in higher accumulation of the protein within the plant.     

A comparative evaluation of alcoholic motivation in animals by 2 behavioral methods]

The attitude of outbred white male rats to alcohol was determined by means of two behavioural methods--the method of free choice of alcohol or water and of reaction of preference of place (PP) connected with taking of alcohol. Conclusion is made about greater adequacy of PP application for determination of alcohol motivation in animals.     

The antigenic and allergenic properties of an extract from the house dust mite Dermatophagoides farinae]

To evaluate the antigenic composition and allergenic activity of D. farinae extracts, the methods of rocket and cross immunoelectrophoresis, gel chromatography and the inhibition of the radioallergosorbent test have been used. The presence of 9-20 antigenic components has been established. The fractions of the extract with a molecular weight of 10-200 kD possessed the highest capacity of inhibiting the binding of specific IgE antibodies from the pool of sera from patients sensitized to D. farinae.     

The reactogenicity and antigenic activity of a meningococcal group B vaccine made from a natural complex of the specific polysaccharide and outer membrane proteins

Group B meningococcal vaccine consisting of the natural complex of specific polysaccharide and outer membrane protein (OMP) has been shown to be moderately reactogenic, safe with respect to the effect of undermining tolerance to human brain tissue antigens and to produce no allergization of humans. The vaccine under study possesses antigenic activity: (a) immunization with this vaccine ensures the fourfold rise of the level of antibodies to the group-specific polysaccharide of group B meningococcus in about 80% of persons with the initially low level of antibodies, this percentage being retained during the whole period of observation, i. e. 85 days; (b) the vaccine enhances the level of antibodies to meningococcal OMP, determined in the enzyme immunoassay and the passive hemagglutination test; (c) these data are indicative of the expediency of immunizing the risk groups of persons with the initially low level of antibodies.     

The comparative activity of cefepime and other current antibiotics against microorganisms isolated from patients in pediatric intensive therapy units]

Comparative activity of cefepime, ceftazidime, ceftriaxone, ciprofloxacin, imipenem and piperacillin/tazobactam against isolates from patients of pediatric intensive care units within October-December 1998 was studied. The isolates were identified with the Walkaway-40 System. The antibiotic susceptibility was evaluated by the E-test on the Mueller-Hinton II agar. The data were interpreted in accordance with the NCCLS. The number of the isolates totaled 100. Among them not more than 10 to 12 strains belonged to the same species. 92 per cent of the isolates was susceptible to cefepime and 70 to 75 per cent of the isolates were susceptible to the third generation cephalosporins. Piperacillin/tazobactam proved to be highly susceptible, the number of the isolates resistant and moderately resistant to it being 6 and 1 per cent respectively. The results showed that cefepime was intermediate between the third generation cephalosporins and carbapenems.     

The characteristics of the course of Leishmania and Pneumocystis opportunistic infections in immunosuppressed laboratory animals

Specific features of the course of Leishmania and Pneumocystis infections were studied on experimental models. Laboratory animals were subjected to medicinal suppression with Tricort-40. Leishmania infection in naturally susceptible animals was considerably aggravated (in comparison with the controls) in the presence of even short-term immunosuppression. Pneumocystis infection developed in experimental animals under the effect of double suppression. The process of the reactivation of Pneumocystis infection was influenced by Leishmania infection, rapidly developing in the presence of prolonged immunodeficiency. The results thus obtained make it possible to regard Leishmania infection in animals with reactivated Pneumocystis infection as co-infection having the properties of a biological, immunosuppressant. Such situation may be extrapolated on HIV/visceral leishmaniasis co-infection.