[Possible diagnosis of Pseudomonas aeruginosa infection by an immunoenzyme method using pyoimmunogen as the antigen]. / O vozmozhnosti diagnostiki sinegnoinoi infektsii metodom IFA s ispol'zovaniem pioimmunogena v kachestve antigena.

The possibility of detecting P. aeruginosa antibodies in patients by means of indirect solid-phase EIA techniques is shown. This assay is carried out with the use of reagents produced in the USSR: polystyrene assay plates manufactured by the Lenigrad Medpolymer Works are used as carriers, P. aeruginosa vaccine (pyoimmunogen) obtained under semi-industrial conditions at the Mechnikov Central Research Institute for Vaccines and Sera is used as antigenic complex and the commercial preparation produced by the Gamaleia Research Institute of Epidemiology and Microbiology serves as conjugate. The studies have revealed that in 95% of cases the level of antibodies in the sera of patients with acute destructive pneumonia accompanied by pleural empyema, abscesses of internal organs and acute hematogenic osteomyelitis is essentially higher than the level of "normal" antibodies in healthy donors from whom biologically confirmed P. aeruginosa cultures can be isolated. In the groups of patients with similar nosological forms of diseases caused by other infective agents such difference in antibody titers is not detected. These results suggest that the detection of antibodies to P. aeruginosa in patients' sera by means of EIA can be used as an additional test for the diagnosis of P. aeruginosa infections.

Vaccines against Pseudomonas aeruginosa infection: 2. Clinico-immunological investigations.

A new multicomponent Pseudomonas vaccine 'pyoimmunogen' has been developed. It was tested for safety and immunogenicity by immunization of volunteer donors and burned patients. Immune plasma obtained from volunteers was used for treatment of severe forms of P. aeruginosa infections. Pyoimmunogen was shown to be of low toxicity for apparently healthy humans and to induce specific antibody formation. In 16 out of 20 burned patients it had a beneficial effect on the course of the disease and the period of hospitalization was shortened. As a result of complex treatment involving the use of anti-P. aeruginosa plasma 51 out of 60 patients recovered.

Vaccines against Pseudomonas aeruginosa infection: 1. Experimental studies.

An experimental study of several types of vaccines against Pseudomonas aeruginosa has been carried out. Pyoimmunogen, a multi-component vaccine consisting mainly of heat-stable proteins (or polypeptides) with a molecular weight of 20 000 to 60 000, was prepared both by laboratory and production techniques using three or five selected strains of P. aeruginosa. The preparations obtained by both methods were found to be of low toxicity and to induce in mice and rats active immunity against challenge with homologous and some heterologous strains of P. aeruginosa, including the toxigenic PA-103 strain. The Pseudomonas vaccine (PV) was prepared from partly purified water-soluble protein antigens (molecular weight ranging from 10 000 to 100 000) obtained from one (mono-PV) or three (tri-PV) selected strains. Mono-PV was prepared by the method of ultrafiltration and tri-PV--by differential centrifugtion. Both types of vaccines proved effective in active mouse protection tests after challenge with homologous as well as with heterologous P. aeruginosa strains. Mono-PV is supposed to induce species-specific immunity against P. aeruginosa infection in mice.

[Immunoenzyme analysis method for detecting anti-Pseudomonas aeruginosa antibodies in persons inoculated with pyoimmunogen]. / Metod immunofermentnogo analiza dlia vyiavleniia antisinegnoinykh antitel u lits, privitykh pioimmunogenom.

The possibility of using the indirect ELISA techniques for evaluating the level of the post-vaccinal production of humoral antibodies in donors immunized with Pyoimmunogen. P. aeruginosa vaccine, has been studied. The specificity and high resolution of this test system, based on the immobilization of the antigens of the vaccinal preparation on a solid-phase carrier, have been demonstrated. A rational method for the evaluation of specific antibody titers with due regard to the spectrophotometric data indicating the results of the reaction and the degree of the dilution of the serum under test has been proposed.

[Determination of in vivo and in vitro toxin activity. I. A new method of determining in vitro activity]. / Opredelenie aktivnosti toksinov in vivo i in vitro. Soobshchenie I. Novyi metod opredeleniia aktivnosti in vitro.

The potency of 5 toxins of different microbial species has been studied by common in vivo methods and by the in vitro method based on measuring the relative test-microbe growth inhibiting units 50. The possibility of using this method for the determination of toxicity in vitro with a view of studying the potency of diphtheria and gas-gangrene exotoxins, as well as that of Pseudomonas aeruginosa exotoxin, is substantiated.

[Experimental immunological effectiveness and safety of pyoimmunogen vaccine against Pseudomonas aeruginosa infection]. / Immunologicheskaia éffektivnost' i bezvrednost' v éksperimente pioimmunogena-vaktsiny protiv infektsii Pseudomonas aeruginosa.

Pyoimmunogen, a polycomponent vaccine against P. aeruginosa infection, has been obtained in laboratory and semi-industrial conditions. The microbial biomass obtained from the strains belonging to O-serotypes (immunotypes) most frequently occurring in clinical practice has been used for producing protective antigens. The preparations have been found to contain proteins (peptides) and carbohydrates in the ratio 6 : 1 to 8 : 1, as well as traces of 2-keto-3-desoxyoctanate, which is indicative of the low content of endotoxin. The immunogenicity of the preparations has been studied experimentally by the active immunization of mice. In these experiments the animals vaccinated in a single injection were found to be protected from challenge with both homologous and heterologous P. aeruginosa strains. The high level of protection from infection caused by toxigenic strain PA-103 was registered. The preparations have low toxicity: LD50 for mice exceeds 2 mg (in protein content): after the multiple administration (7-10 times) of the preparation to mice and rats the weight of the experimental animals was not significantly different from the weight of the control animals.

[Possibility of obtaining the anaform of E. coli enterotoxin]. / O vozmozhnosti polucheniia anaformy énterotoksina E. coli.

The nontoxic (on the model of raw edema in white mice) anaform of E. coli enterotoxin was obtained under the action of heat and formalin. In the process of detoxication the charge of the enterotoxin molecules was changed. The toxoid thus obtained preserved the antigenic activity of the initial preparation and, when used for the immunization of rabbits, stimulated the production of active antitoxic sera.

[Neutralizing activity of antisera to E. coli enterotoxin and a toxoid type preparation]. / Neitralizuiushchaia aktivnost' antisyvorotok k énterotoksinu E. coli i preparatu tipa anatoksina.

Antisera obtained as a result of immunization of rabbits with concentrated E. coli enterotoxin, its active fraction or toxoid, had a pronounced toxin-neutralizing activity. At the same time the cytotoxic activity of antisera to the purified fraction was considerably higher than that of the antisera to the concentrated enterotoxin. Such antisera had also a neutralizing effect on thermolabile enterotoxin. The neutralizing activity of antisera to E. coli enterotoxin was clearly manifested in the paw edema test.

[Use of the passive hemagglutination inhibition reaction for the purpose of determining the antigenic activity of anatoxins in vitro]. / Ispol'zovanie reaktsii tormozheniia passivnoi gemaggliutinatsii s tsel'iu opredeleniia antigennoi aktivnosti anatoksinov in vitro.

The work deals with the study of the possibility of using the passive hemagglutination inhibition test (antibody neutralization) for the determination of the antigenic activity of botulinum toxoids, types A, B and E. Erythrocytic diagnostic preparations were shown to allow the determination of up to 0.1 g of antigen. At the same time in vitro determinations were found to satisfactorily correlate with the results of in vivo determinations of the antigenic activity of these toxoids in the antitoxin-fixation test.

Experimental study of vaccines against Salmonella typhimurium infection.

Serological and protective activities of vaccines from S. typhimurium and S. minnesota were studied. It has been demonstrated that active protection against infection in experimental salmonellosis in mice can only be obtained by immunization of the animals using vaccines from complete antigenic complexes isolated from S-strains. It has been found that expressed anti-infection immunity (unlike anti-endotoxic immunity) is induced to the same extent by either high-molecular components (2,000,000 daltons and more), showing great serological activity, or components with relatively low molecular weight (15,000--20,000 daltons) and minimum serological activity. Vaccines from Ra- and Re-strains of S. minnesota do not induce resistance to S. typhimurium infection in mice in either active protection tests or passive protection tests.

[Dynamics of biologically active enterotoxin release by E. coli]. / Dinamika vydeleniia biologicheski aktivnogo énterotoksina E. coli.

Accumulation of E. coli enterotoxin in the Finkelshtein's culture medium in growing the cells in a 30-litre reactor was studied. Accumulation of active highly molecular enterotoxin occurred in the course of a 6-hour cultivation of E. coli, strain P-99 (O141: K85ab; K88ab: H4) in the fluid medium under aeration. Oxygen utilization, synthesis and release into the nutrient medium of pyruvic acid, and protein accumulation were observed. The preparation obtained was stable to the lyophylic drying, contained thermolabile and thermostable toxins and marked edema of mouse limbs. The data obtained were of significance for the industrial production of active enterotoxin preparations.

[Edema of the paws of white mice--test for assessing the activity of E. coli enterotoxins]. / Otek lap belykh myshei--test dlia otsenki aktivnosti émterotoksinov E. coli.

The authors studied the paw edema test in mice for detection of the E. coli (strain P-99) enterotoxins activity. This test proved to be simple, sensitive and reproducible; it permitted to determine the activity of thermostable and thermolabile enterotoxins and endotoxin; the mentioned test was particularly useful in testing various preparations of enterotoxins obtained during their extraction and purification.

[Evaluation of the quality of dry anatoxins in the process of their production]. / Otsenka kachestva sukhikh anatoksinov v protsesse ikh proizvodstva.

On the example of production of botulin toxoids of A, B and E types the authors demon strated the expediency of using the agar gel diffuse precipitation test for preliminary assessment of the toxoid activity, instead of a more expensive and complicated antitoxin-binding test.