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The new Russian enzyme immunoassay system "CMV-Diagnost" based on the detection of low-avid IgG antibodies has been developed for the rapid diagnosis of cytomegalovirus infection. The system was found not only to determine the strained immunity in response to cytomegalovirus, but also to judge the current infection from the avidity index of detectable IgG antibodies with a high degree of validity. The antibody avidity index of less than 30% suggests an acute stage of primary cytomegalovirus infection. The minimum antibody threshold bodies (deltaOD has been established for the correct interpretation of data on low-avid antibodies. deltaOD of > or =0.6 optic units was for the developed test system "CMV-Diagnost. A correlation was found between the serum levels of low-avid antibodies and IgM antibodies to cytomegalovirus at the acute stage of the disease.

A Russian immune-enzyme test-system ("HERPES-DIAGNOST") was designed on the basis of detection of low-avidity IgG antibodies in order to promote the laboratory value of serological examinations of patients with different clinical manifestations of the herpetic infection. The key test parameters were tuned; the immunosorbent production based on antigens (herpes simplex virus--HSV), types 1 and 2, was optimized; and the concentration was chosen for the main reagent that removes the low-avidity antibodies (8 M urea solution) and, finally, the temporal and temperature regimes were selected for testing. A system was elaborated for registering and interpreting the results. The avidity index of antibodies lower than 35% was found to be a reliable criterion confirming the presence of acute primary infection triggered both by HSV-1 and by HSV-2. If there is a relapse of herpetic infection, the avidity index of antibodies can range from 30 to 45%.

A direct proof of intensification of associative nitrogen-fixation activity and considerable increase of intake of biological nitrogen by the pasture ryegrass plants, when using low doses of ammonium-carbonate compounds (ACC) as compared with ammonium nitrate (AN) has been obtained with the help of labelled nitrogen 15N. The isotope method confirms a possibility of biological nitrogen-fixation intensification in the mentioned culture when using synthetic plant growth regulator of a new generation Triman-1. More efficient use of ACC and AN by plant has been established.

The intensification of activity of associative and symbiotic nitrogen fixation while using low amounts of ammonium-carbonate compounds, carbonic-ammonium salts, in particular, has been established. The main ways and mechanisms of the action of ammonium-carbonate salts as a new and perspective agrochemical on physiological and biochemical processes of microorganisms and agricultural plants were presented on the basis of the analysis of literary information and the author's investigations.

The impact of oral administration of heat-killed bifidobacteria, lactobacteria, enterococci and bacteroides on mouse resistance to experimental salmonellosis and content of immunoglobulin-synthesizing cells in the proper plate of the small intestine was studied. It was shown that the administration of the killed bifidobacteria, lactobacteria and enterococci increased the animal resistance to experimental salmonellosis infection and induced an increase in the content of immunoglobulin-synthesizing cells in the proper plate of the small intestine. The administration of the killed bacteroides had no such effect. Possible development of bacterial preparations with immunomodulating properties based on killed bifidobacteria, lactobacteria or enterococci is discussed.

The authors prepared 156 mouse hybridomas producing monoclonal (MCA) antibodies to type- and group-specific antigenic determinants of HSV-1 and HSV-2. Seven of them were studied at length by western blot and radioimmunoprecipitation methods. The cell lines 1H97 and 2H141 were shown to produce immunoglobulins of G2 beta and M class, respectively, and were directed against group-specific antigenic determinants of the major nucleocapsid protein p150. The cell lines 1H38 and 1H110 produced immunoglobulins of M and G2 beta, respectively, and were directed against type-specific antigens of HSV-1 glycoprotein gB. At the same time, the presence of group-specific antigenic determinants on glycoprotein gB molecule was indicated by MCA 1H188 belonging to immunoglobulins of G2 alpha class. Two cell lines, 2H208 and 1H225, produced immunoglobulins G2 alpha directed against type-specific antigenic determinants of HSV-2 glycoprotein gD and group-specific antigenic determinants of HSV-1 gD, respectively. The results of immunoelectron microscopy indicated that MCA 1H110 and 2H208 were directed against virus envelope proteins.

The possibility of stimulating the immunity of totally decontaminated mice, kept isolated under germ-free conditions, with the use of killed L. acidophilus Solco strains has been studied. As revealed in this study, the oral and intraperitoneal administration of strains O1 and O6 to mice leads to a significant increase in the content of immunoglobulin-synthesizing cells in the jejunal lamina propria of the animals. The oral administration of L. acidophilus Solco strain O6 and the intraperitoneal injection of L. acidophilus Solco strain O1 have been found to lead to a significant rise in the level of luminol-dependent chemiluminescence of mouse peritoneal macrophages. The total decontamination of mice induces the development of secondary immunodeficiency which influences the effectiveness of immunostimulating agents.

Eight recombinant clones were obtained by insertion of BamHI fragments of herpes simplex type I viral DNA into a vector plasmid pUC19o. Of the obtained clones 5 were found to hybridize with herpes simplex type I and 2 viral DNA while 3 clones revealed a positive reaction with the Vero cells DNA. A constructed DNA-probe possessing the highest level of activity was selected for further studies. The probe is a BamHI fragment of herpes simplex type I viral DNA labelled with 32P dTTP. Probe sensitivity in blot hybridization is 10 pg for identification of type I viral DNA and 50 pg for type 2 viral DNA. The DNAs of cytomegalovirus and herpes zoster virus do not show positive signals with the probe. The increased sensitivity of the used dot hybridization as compared with biological or IEA antigen identification of the virus was confirmed with the clinical material from 59 patients with the different clinical manifestations of the herpes viral infection.

The sensitivity and specificity of the enzyme immunoassay (the capture variant), based on the use of the complex of anti-IgM-IgM to purified measles virus, the peroxidase-labeled lysate and nucleocapsid antigens of measles virus, were evaluated. The advantages of the nucleocapsid conjugate were established. The study of 200 serum samples from measles patients revealed that antimeasles IgM antibodies could be detected in 100% of cases, and the assay of 15 serum samples from healthy donors and 5 serum samples from patients with autoimmune diseases did not yield a single false positive result.

A clinical description of generalized herpes in a pregnant patient is presented. Virological and serological studies have confirmed the diagnosis.

The respiration rate of 25 studied oligonitrophilous strains belonging to various genera and species of bacteria varied within wide limits depending on their taxonomy, conditions of cultivation, substrates, and other factors. No strict correlation was established between the respiration rate and the activity of nitrogen fixation. One of the typical properties of oligonitrophilous bacteria is a high rate of endogeneous respiration --50% and more of the respiration rate during assimilation of exogeneous substrates. The level of oxidative metabolism of oligonitrophilous bacteria was found to be higher on media containing bound nitrogen than on media without nitrogen.

Mycobacterium flavum 158a can produce exopolysaccharides whose quantity varies, depending on the culture age, from 88.2 to 186.8% of the cell biomass weight in a medium with sucrose and from 1.3 to 25.0% in a medium with a polysaccharide synthesized by the oligonitrophilic bacterium Pseudomonas sp. 158a. The absolute and relative content of exopolysaccharides in the cultural broth decreases during the intensive growth of M. flavum 158a. This appears to be caused by their assimilation as a carbon source in the processes of energy and constructive metabolism. The exopolysaccharides of M. flavum 158a contain galactose, glucose, mannose, fucose, xylose, ramnose and a lipophilic sugar X1 at the molar ratio 10:11:11:8:11:12:16 as well as a non-identified sugar X2 with the Rf below than that of ramnose. The exopolysaccharide of M. flavum 158a was shown to be heterogeneous. It is composed of at least 16 fractions differing in molecular mass (from 98,980 to 490 D), quantity (from 2 to 8), composition and percentage of the constituent monosaccharides.

The selective survey of the population of the Republic of Congo for the presence of antibodies to orthopoxviruses has been carried out with the use of the neutralization test, the hemagglutination inhibition (HAI) test and the ELISA. Despite a prolonged period (15 years) elapsed since the transmission of natural smallpox stopped in this country and despite the almost complete cessation of immunization against this infection since 1977, antibodies to orthopoxviruses can be detected in a considerable proportion of the population: 29%. This percentage grows as older age groups are examined, reaching 90.6% in the age groups of 16 years and over. Antibodies to orthopoxviruses have also been detected in children under 5 years of age, born after the eradication of smallpox and having no vaccination scars. The possible causes of this phenomenon are discussed. The comparison of the results obtained with the use of different tests has confirmed high sensitivity of ELISA. The HAI test is less sensitive, but this is compensated by its simplicity and its easy use for screening procedures. Besides, the positive results of this test indicate that the corresponding sera contain sufficiently high titers of virus-neutralizing antibodies detected by means of ELISA, which is of importance for their subsequent interspecific differentiation.

Oligonitrophilic bacteria were cultivated on a medium containing only 2.5--10.0 mg/litre of nitrogen compounds. They assimilated elementary nitrogen only after utilization of these nitrogen compounds during growth and formation of nitrogen-fixing enzyme system. Their cells grown on a medium containing high concentrations of bound nitrogen did not fix nitrogen during further incubation in the atmosphere of 15N; therefore, the enzymes involved in nitrogen fixation were induced. These organisms are characterized by diauxia during their growth on media containing "start" doses of nitrogen. Enzymes catalysing nitrogen fixation in azotobacter are also induced. But, contrary to oligonitrophilic bacteria, the azotobacter does not require nitrogen compounds in the medium in order to adapt to molecular nitrogen, and its growth curve is not of a biphasal character. These data and the evidence of other authors suggest that all nitrogen-fixing microorganisms are characterized by the induced, not constitutive, enzymes involved in reduction of molecular nitrogen.

The successful application of the immunoperoxidase method of (IP) with light microscopy for rapid detection of certain togaviruses and orthopoxviruses and antibodies to them is described. A comparative evaluation of the IP and immunofluorescent (IF) method for these purposes was performed. The results indicate practically similar sensitivity and specificity of both methods. The detection of viral antigen directly depended upon the infective dose and time of examinations (within 4--12 hours postinoculation). In evaluating the IP method, however, the account should be taken of the fact that it does not require expensive equipment and therefore may be used in any practical laboratory or even under field conditions. Rapid detection of both viral antigens and antiviral antibody by this method opens approaches for its wide application in the future.

CSF was studied in 110 patients with herpes zoster. The whole complex of symptoms helped to diagnose serous meningitis in 62% of cases and so-called "asymptomatic meningitis" in 18% of cases. CSF cells were characterized by lymphocyte transformation and the presence of antigen to Varicella zoster virus determined by the fluorescent antibody method. Specific antibodies titer appeared to be at zero or minimal level. The disease pathogenesis is discussed.

Changes of antibody formation of 96 patients with various clinical forms of herpes zoster were traced by indirect hemagglutination inhibition test. Four variants of the immunological response were distinguished; clinical characteristics of each of these groups is presented. The initial antibody level failed to determine the severity of the course of the disease in herpes zoster.

The results of examinations of sera, blood and organs of different species of monkeys from some Asian and African countries for the presence of antibody to smallpox and viruses of the smallpox group. Significant titers of smallpox antibodies (antihemagglutinins virus-neutralizing and, in some cases, precipitating antibody) were found in a considerable number of monkeys shot near foci with human cases (Equatorial province of Zair Republic). In the same monkeys kidney tissues yielded 3 isolates of smallpox virus group two of which were indistinguishable in the laboratory tests from variola virus. On the basis of these data it is concluded that smallpox viruses circulate among wildlife monkeys in some areas of Equatorial Africa. Further studies along these lines are necessary.

To differentiate antibodies to monkeypox and vaccinia viruses, the solid-phase ELISA with preliminary adsorption of sera with vaccinia virus was used. The identification of antibodies in 99 serum samples obtained in the Republic of Congo from children without vaccination scars was carried out by means of this assay. No antibodies to monkeypox virus were revealed. In 62% of cases the presence of antibodies was due to vaccinia virus. In the sera of 32% of children under examination antibodies differing from those to vaccinia and monkeypox viruses were revealed. To find out the origin of these antibodies, further seroepidemiological studies are necessary.

A panel of 18 hybridomas producing MCA to measles virus (the L-16 strain) was produced by somatic hybridization method. Thirteen hybridomas produce immunoglobulins of the G class represented by all known subclasses of mouse immunoglobulins; the subclass G 2a is predominant. Five hybridomas produce immunoglobulins of the M class. The resulting preparations of MCA are highly reactive in several serological tests: IFA, NIF, HI, NT. MCA have been divided into 3 groups according to their capacity to combine with three strains of morbilli viruses: L-16, LEC, and carnivora distemper virus (strain EPM).

Data on comparative studies of the sensitivity of enzyme-linked immunosorbent assay (ELISA), complement fixation test (CFT), and indirect immunofluorescence test (IIFT) in titration of antibodies to chlamydial agents of calf enteritis and pneumonia in sera of immunized rabbits are presented. The data indicate that ELISA is 10-40 times more sensitive than CFT and IIFT and may be used for large-scale diagnostic studies in chlamydial infections of cattle.

The results of the preparation of peroxidase conjugates on the basis of the Fab-fragment of rabbit antivaccinal serum IgG and pure antirabbit IgG are presented. Peroxidase conjugates prepared on the basis of highly purified antibodies have been found (in vaccine virus-infected cell cultures) to ensure greater reliability of the immunoperoxidase method due to the decrease of nonspecific reactions registered by the control test system. This allows recommending peroxidase conjugates prepared on the basis of higher purified antibodies for use in diagnostic tests.

A method for preparation of an erythrocyte immunoglobulin herpes preparation for the indirect hemagglutination test (IHA) is described. A high specificity and sensitivity of this test and the preparation has been demonstrated. The results of the use of IHA with this preparation for the detection of herpes simplex virus in specimens from patients are presented.

Clinical examination of 83 patients with generalized herpes zoster has given the authors grounds to regard this disease as a result of activation of latent varicella-zoster virus. This assumption was confirmed by the results of indirect hemagglutination inhibition tests with 37 serum specimens taken from 18 patients. Treatment with antibiotics, the drug proper-myl, and by dehydration was the more effective, the earlier the patients were admitted to the clinic. Dehydration, proper-myl and combination of chloramphenicol with dehydration produced a more beneficial effect than the antibiotic alone. Five patients died. Problems of pathogenesis are discussed.

The results of testing the blood sera obtained from donors at a blood transfusion center in Moscow for the presence of antibodies to rubella, measles and herpes simplex viruses, carried out by means of the enzyme immunoassay with the use of the corresponding test systems, are presented. Antibodies to rubella, measles and herpes simplex viruses have been detected, respectively, in 81.5, 96.7 and 100% of blood sera. The proportion of sera with low, medium and high antibody titers has proved to be virtually the same with respect to antibodies to rubella and herpes simplex viruses, the sera with medium antibody titers constituting 59%. At the same time tests for measles antibodies have shown the prevalence of sera with low titers (49.2%) with the highest percentage of seronegative donors (18.5%, as compared with 3.3% in rubella and the absence of negative sera in herpes simplex).

On the basis of proteins A produced at the Mechnikov Central Research Institute for Vaccines and Sera (Moscow) and obtained from Pharmacia AB (Sweden), several batches of peroxidase conjugate have been prepared by a modified method of periodate oxidation. The preparations thus obtained have been evaluated by means of the corresponding enzyme immunoassay systems for the detection of antibodies to herpes simplex and measles viruses. The results of this investigation indicate that serum antibody titers, determined in the assays with antispecific conjugates and with protein A-based based conjugates, coincide. The comparative study of conjugates prepared on the basis of Soviet and imported proteins A has demonstrated their similar activities and specificities.

A diagnostic preparation for the indirect hemagglutination test (IHA) was obtained by sensitization of fixed tannin-treated sheep erythrocytes with IgG-fractions from human herpes zoster convalescent sera. A high specificity of the preparation was established in comparative experiments. It could detect the varicella-herpes-zoster virus antigen in 100% of specimens from patients. The IHA test with this erythrocyte diagnostic preparation is simple, economic, gives the results within 1-1 1/2 hours after the specimens arrive in the laboratory. A great advantage of this test ipesviruses.

The levels of serum and salivary immunoglobulins and serum antibodies to 5 different antigens (diphtheria toxoid, Escherichia coli and Shigella sonnei O-antigens, bovine serum albumin and ovalbumin), as well as heterohemagglutinins , were studied in 29 persons with complete or partial IgA deficiency. In 27% of cases an increase in the level of serum IgA was observed, such increase occurring more frequently in complete than in partial IgA deficiency. A rise in the level of serum antibodies, especially those to alimentary and enterobacterial antigens, was established; the degree of this rise was not correlated with the degree of disturbances in the systemic synthesis of IgA. In complete IgA deficiency not only serum, but also salivary IgA was absent; in some cases saliva contained no secretory component as well. In partial IgA deficiency the level of salivary IgA was normal. The characteristic features of systemic and local immunity in a varying degree of disturbances in the synthesis of IgA are discussed.

A method for obtaining an erythrocyte diagnostic preparation for detection and titration of herpetic antibody in the passive hemagglutination test is reported. The use of this preparation for quantitative assay of herpetic antibody in sera from herpes simplex patients detected antibody in 100% of cases. Considerably less frequent findings of herpetic antibody were in human sera from diseases of other etiologies and in donor sera. Titers of antibody detected in the PHA test were 2--10 times higher than in the CFT. However, no differences between the PHA test and the CFT were found in per sent of seroconversions and in increase of antibody titers. The method is simple, sensitive and easy to perform in any clinical laboratory.