[The study of experimental and natural rotavirus infection in mice using a heterologous enzyme immunoassay test-system]. / Izuchenie éksperimental'noi i estestvennoi rotavirusnoi infektsii myshei s pomoshch'iu geterologichnykh test-sistem immunofermentnogo analiza.

Enzyme immunoassay test systems constructed on the basis of heterologous calf and monkey rotaviruses were shown to be applicable for diagnosis and study of the pathogenesis of experimental and natural rotavirus infection of mice.

[Development of test systems of immunoenzyme analysis for the rapid diagnosis of rotavirus infection]. / Razrabotka test-sistem immunofermentnogo analiza dlia bystroi diagnostiki rotavirusnoi infektsii.

A test system of enzyme immunoassay (EIA) consisting of simian rotavirus SA-11 and rabbit antiserum has been developed for the detection of rotavirus antigen. Direct EIA was used for tests on stool specimens from 289 children varying in ages from 10 days to 12 years suffering from acute enteric infections and 56 normal children. The antigen was detected in 22.1% and 3.5%, respectively, in patients predominantly in the first 3 days of the disease and most frequently in cases running as gastroenteritis. The results are discussed with reference to the possibility of the development of rotavirus carrier state and mixed virus-bacteria infections.

[Differences in the gene structure of the matrix protein and hemagglutinin in remantadine-resistant and -sensitive variants of the influenza virus type A FPV]. / Razlichiia v strukture genov matrikskogo belka i gemaggliutinina ustoichivogo i chuvstvitel'nogo k remantadinu variantov virusa grippa tipa FPV.

The oligonucleotide mapping technique and RNA-RNA hybridization revealed structural differences between the HA- and M-protein genes of two variants of influenza A FPV, remantadine-sensitive and remantadine-resistant ones. A quantitative estimation of the structural divergence of the two influenza FPV pairs of genes was carried out. The possible functional role of the differences in the structure of the HA- and M-protein genes of the two FPV variants is discussed.

[Suppression of rotavirus SA-11 reproduction by protease inhibitors in cell culture]. / Podavlenie reproduktsii rotavirusa SA-11 ingibitorami proteaz v kul'ture kletok.

The effect of proteases inhibitors, epsilon-amino-caproic acid and gordox, on reproduction of rotavirus SA-11 in MA-104 cells was studied by enzyme immunoassay. These inhibitors were shown to exert an inhibiting effect on rotavirus reproduction.

[Rapid diagnosis of rotavirus infections by RNA electrophoresis on polyacrylamide gel]. / Bystraia diagnostika rotavirusnykh infektsii putem élektroforeza RNK v poliakrilamidnom gele.

A method of rapid diagnosis of rotavirus infections is described. It is based on the isolation of viral RNA from the feces of patients with viral gastroenteritis and determination of RNA mobility by 6% polyacrylamide gel electrophoresis. It was demonstrated that rotavirus infection could be diagnosed after long-term storage of fecal specimens as well. The method is of interest for epidemiological and genetic studies of human rotavirus diseases.

[Morphological characteristics of the rotaviruses and the structure of their genome]. / Morfologicheskaia kharakteristika rotavirusov i struktura ikh genoma.

The data on human and animal rotavirus reproduction in monkey kidney cell culture, their morphology, and genome structure are presented. Both viruses, simian rotavirus SA 11 and human rotavirus K1, did not differ morphologically, in both cases two-capsid and one-capsid particles were found. The genome structure was determined by electrophoresis in 6% PAG. The electrophoretic mobility of genome fragments of both viruses was similar.

[Conditions for the development of a leiomyosarcoma in an experiment on mice]. / Izuchenie uslovii razvitiia leimiosarkomy v éksperimente na myshakh.

A protective effect of homologous serum interferon on leiomyosarcoma of connective tissue in mice was established. The total amount of interferon used per mouse was 32000 64000 units/ml. The per cent of protection was 61 against 26 of natural protection in control.

[Antitumor effect of a tumor-cell neuraminidase vaccine]. / Protivoopukholevyi éffekt neiraminidaznoi vaktsiny opukholevykh kletok.

The effect of neuraminidase vaccine of CBA mouse sarcoma cells caused by simian adenovirus SA7 (C8) on growth parameters of transplanted sarcoma in a syngeneic system was studied. Inoculation of the vaccine was found to inhibit tumor growth. This effect was more marked in a group of animals given tumor cells after preliminary vaccination. There was no correlation between tumor growth parameters and cytotoxic activity of spleen cells assesses in the cytotoxicity test by 51Cr release in the groups of vaccinated and control animals. It is concluded that the treatment of tumor cells with neuraminidase increases their immunogenicity. The cytotoxic activity of spleen cells in vaccinated animals appears earlier and persists longer.

[Humoral immunity factors in the pathogenesis of recurrence in chronic herpetic infection]. / Faktory gumoral'nogo immuniteta v patogeneze retsidivov khronicheskoi gerpeticheskoi infektsii.

A comparative study of various factors of humoral immunity in human chronic herpes stomatitis (CHS) in periods of relapses and remission of the infection showed the exacerbations of the disease to occur in the presence of complement-fixing (CF) and virus-neutralizing (VN) antibodies in the blood serum the titres of which moderately rose with the progress of the infection. A relapse of the disease occurs during marked decline in the content of secretory IgA and true secretory Sc-IgA, serum and secretory IgG, low levels of serum interferon, and a small rise in titres of 19S specific CF antibodies. Remission comes as these values become normal. Although specific immunological changes do occur in CHS, they are not very marked, whereas the factors of nonspecific host resistance change considerably in close correlation with the periods of relapse and remission of the infection.

[Cellular immune response detected in blast transformation test with lymphocytes from rabbits immunized with nucleocapsid of herpes simplex type 2 virus]. / Kletochnyi immunnyi otvet, vyiavliaemyi v reaktsii blasttransformatsii limfotsitov krolikov, immunizirovannykh nukleokapsidom virusa prostogo gerpesa tipa 2.

A preparation of herpes simplex virus type 2 (HSV-2) nucleocapsid (NC) was obtained after treatment of intracellular virus with detergents followed by centrifugation in linear sucrose density gradient. Electron microscopic analysis revealed polymorphism of HSV-2 NC population. Three main types of capsid structures were found: empty capsids, NC containing various amounts of nucleoid material, and NC with complete nucleoid. Morphological heterogeneity correlated with heterogenous sedimentation profile of the total NC preparation of labeled virus represented by light, intermediate, and heavy structures. Specific blasttranformation tests with lymphocytes from rabbits immunized with HSV-2 NC demonstrated differences in the primary and secondary cellular immune responses. The secondary cellular immune response was characterized by a more rapid and strong increase in BTT values than the primary immune response.

[Differences in the properties of the interferons produced by the leukocytes of healthy persons and of cancer and leukemia patients]. / Razlichiia v svoistvakh interferonov, produtsiruemykh leikotsitami krovi zdorovykh liudei, bol'nykh rakom i leikozom.

In vitro production of interferon by blood leukocytes from patients with lymphosarcoma, lymphogranulomatosis, leukemia, cancer tumours, pneumonia, as well as by leukocytes of mice with Rauscher leukemia, and mice in the condition of hyporeactivity to interferon inducer was studied. Alongside with quantitative differences in interferon production, biological differences in the properties of interferons produced of normal and sick humans and animals were revealed. The biological differences consist in that the interferon produced by leukocytes from cancer and leukemia patients interacting with homologous cell culture is conducive to more rapid formation of resistance to the indicator virus than the interferon produced by normal leukocytes. Thus, resistance of the homologous cell culture to the infection with the indicator vesicular stomatitis virus developed within 1--2 hours after contact with leukocyte interferon from patients and only within 5--6 hours after contact with that of normal subjects. This finding is not specific for cancer and leukemia, as the same was observed with specimens from patients with pneumonia and from mice hyporeactive to interferon inducer. It is suggested that patients with cancer and leukemia have a state of interferon hyporeactivity.

[Modelling of viral-chemical carcinogenesis in chronic infection in mice caused by the herpes simplex type 2 virus]. / Modelirovanie virusno-khimicheskogo kantserogeneza v usloviiakh khronicheskoi infektsii, vyzvannoi virusom prostogo gerpesa tipa 2.

The influence of chronic herpetic infection of white mice caused by herpes simplex virus type 2 (HSV-2) on the blastomogenic effect of a polycyclic hydro-carbon, 20-methylcholanthrene (20-MCA), was studied. Solid tumors developed in 20-MCA-treated mice on the side of the carcinogen administration within 81--89 days. The simultaneous administration of 70 intracerebral LD50 of HSV-2 subcutaneously into a hind leg pad and 0.1 mg 20-MCA subcutaneously into the inguinal area was accompanied by a synergistic action of the two factors. The number of tumors in the animals treated with HSV-2 in combination with 20-MCA at all intervals of observation was 1.5--2.5 times greater than in mice treated with 20-MCA alone. Mice weighing 10--12 g were more sensitive to the synergistic effect of HSV-2 and 20-MCA, whereas animals weighing 25--30 g were more sensitive to the carcinogenic effect of 20-MCA alone. No tumors developed in mice infected with HSV-2 alone by 167 days (the observation period). Mice weighing 10--12 g were found to be more sensitive to the fatal effect of HSV-2 and HSV-2 plus 20-MCA, particularly in the first 2--3 weeks after inoculation. Six months after inoculation with HSV-2 the virus was isolated from posterior root ganglia of the sacral and lumbar spinal cord by cocultivation of the ganglia with human embryo skin-muscle tissue cells.

[Comparative study of the effectiveness of the purification and concentration of herpes simplex virus types 1 and 2]. / Sravnitel'noe izuchenie éffektivnosti ochistki i kontsentratsii virusa prostogo gerpesa tipov 1 i 2.

The results of comparative studies on concentration and purification of herpes simplex virus type 1 and type 2 (HSV-1 and HSV-2) by ficol density gradient centrifugation are presented. A two-phase distribution of extracellular HSV was established in phycol density gradient centrifugation: in zones with density of 1.110-1.114 and 1.088-1.085 g/ml. The effectiveness of purification of HSV preparations recovered from the corresponding gradient zones was determined by electron microscopy and quantitation of the contaminating cellular (radioactive) proteins in virus purification from a mixture of the culture fluid from infected cultures and the culture fluid from uninfected labeled human embryo skin-muscle tissue cultures (HESM) and a mixture of unlabeled extracellular HSV and a homogenate of labeled uninfected HESM cultures. In HSV purification from the virus-containing culture fluid the amount of cellular proteins was shown to decrease 500-fold in 150-fold virus concentration. In purification of extracellular HSV from the mixture with cell homogenate the amount of cellular proteins decreased 70- and 100-fold for HSV-2 and HSV-1, respectively. The infectious virus yield in phycol gradient centrifugation of a precipitate obtained by the addition of polyethylene glycol-6000 to the culture fluid for HSV-1 was 34.7% (in titrations in HESM cultures) and 38.4% (by intracerebral inoculation of mice weighing 5-6 g), and for HSV-2 20.2% and 26.3%, respectively.

[Comparative study of the oncornavirus A and D proteins of human J-96 cells by the methods of isoelectric focusing and polyacrylamide gel electrophoresis]. / Sravnitel'noe izuchenie belkov onkornavirusov A i D v perevivaemykh kletok cheloveka J-96 metodami izoélektricheskogo fokusirovaniia i élektroforeza v poliakrilamidnom gele.

Three peaks of 14C-radioactivity with buoyant densities of 1.23--1.24, 1.26 and 1.29 g/ml were detected in a cytoplasmic extract of J-96 cells upon equilibrium centrifugation in sucrose gradient. Electron microscopy of the 1.23--1.24 g/ml buoyant density fraction revealed particles 60--80 nm in diameter showing morphology characteristic of oncornavirus A. Isoelectric focusing in polyacrylamide gel showed polypeptides of extracellular D virus and oncornavirus A to differ in isofocusing points (pI). Proteins of extracellular D virus were localized in zones with pH 3.7, 4.0, 4.4, 4.7, 5.6, 6.5, 8.1, 9.45, and 10.0; polypeptide of intracytoplasmic oncornavirus A had the following isofocusing points: 4.0, 4.9, 6.7, 7.3, 9.0, 9.45 and over 10.0. Electrophoresis of polypeptides of D virus and intracellular oncornavirus A revealed differences in the molecular weights of the components. No proteins with molecular weights of 10,000, 12,000, 15,000, and 27,000 dalton characteristic of the extracellular D virus were found in oncornavirus A virions. The analysis of protein patterns obtained in parallel experiments of isoelectric focusing and polyacrylamide gel electrophoresis suggests that oncornaviruses A and D of J-96 cells differ in the characteristics (pI and molecular weight) of the structural polypeptide components.

[Effect of exogenous interferon on the course of latent oncornavirus infection of J-96 cells]. / Vliianie ékzogennogo interferona na techenie latentnoi onkornavirusnoi infektsii kletok J-96.

The effect of exogenous leukocyte interferon on the course of chronic oncornavirus infection of lymphoblastoid J-96 cells chronically producing type B virus was studied. By means of radio-isotope analysis and electron microscope examinations it was shown that upon long-term passage of the cells (18-34 passages) in the presence of interferon (10 units/ml) the process of virion formation in the cells was inhibited 2.0-4.4-fold and virus budding to a lower extent (1.6-2.7-fold). Interferon exerted no inhibiting effect on the formation of intracytoplasmic virions of type A. The employment of KC-test showed the oncornavirus produced by J-96 cells in the presence of interferon to have retained its biological activity, being able to induce synthesis of the indicator KC cells. Examination of the cell membranes by electrophoresis in polyacryl amide gel showed that interferon contributed to accumulation of glycoproteins with high molecular weights (115 000, 100 000 and 68 ooo daltons) in this cell fraction. Simultaneously the experimental cells were found to have 2-3-fold increased amount of inter-species group-specific antigen of Mason-Pfizer virus. The mechanism of action of interferon on multiplication of J-96 cell oncornavirus is discussed.

[Analysis of influenza virus reproduction under conditions of chronic infection]. / Analiz reproduktsii virusa grippa v usloviiakh khronicheskoi infektsii

The results of comparative studies of influenza virus, original and produced in KM cells under conditions of chronic infection (KM WSN) are presented. The WSN KM virus was shown to band in the density range of 1.18 to 1.23 g/ml, with maximum at a.215 g/ml. The electrophoretic analysis of the standard virus RNA revealed mostly heavy fragments. The analysis of a total RNA preparation from the virus population produced by chronically infected cells revealed both heavy and light RNA fragments. The total synthesis of cellular DNA and RNA was slightly inhibited by KM WSN. A mechanism of persistence is suggested associated with continuous production of defective non-infectious particles.

[Chronic infection of diploid cells of human embryo musculocutaneous tissue]. / Khronicheskaia infektsiia diploidnykh kletok kozhno-myshechnoi tkani émbriona cheloveka

A model of chronic influenza infection of a strain of human embryo skin-muscle tissue diploid cells (KM WSN) was developed. When the cells were propagated without medium changes, they regularly produced virus in low infectious titres and hemagglutinins in titers of 1 : 2 to 1 : 4. Frequent medium changes caused more intensive infectious virus reproduction with no or very poor hemagglutinin accumulation. Superinfection of KM WSN cultures even with frequent medium changes led to a marked reduction in the amount of infectious virus production with no detectable interferon. The WSN KM virus was found to differ from the initial variant by a number of markers. The observed pattern of virus production suggests a mechanism of persistence in this system in connection with the interfering effect of the defective virus produced by the cells.

[Virus-specific syntheses in cells infected with the virions from standard and "defective" populations of the influenza virus (author's transl)]. / Virusspetsificheskie sintezy v kletkakh, infitsirovannykh virionami iz standartnoi i "defektnoi" populiatsii virusa grippa

The structure of influenza virus virions from the standard and "Magnus" populations as well as intracellular syntheses induced by them were studied. Virions of influenza virus were shown to be heterogeneous with respect to the set of fragments in them. This heterogeneity was more marked in virions of the "Magnus" population and consisted in a relatively greater deficiency of large fragments. A marked induction of light RNA fractions in the cell by defective influenza virus was demonstrated. Synthesis of protein and the polypeptide composition of virions were found to be similiar in standard and "Magnus" viruses.