[Persistence of the measles virus genome in peripheral blood lymphocytes in patients with glomerulonephritis and systemic lupus erythematosus]. / Persistentsiia genoma virusa kori v limfotsitakh perifericheskoi krovi u bol'nykh glomerulonefritom i sistemnoi krasnoi volchankoi.

Punctate hybridization was used to examine measles virus genome in peripheral blood lymphocytes from patients with glomerulonephritis (GN) and systemic lupus erythematosus (SLE). Measles virus genome was revealed in 47 (54%) out of 87 GN patients, in 27 (74%) out of 36 SLE patients and in none of the control group patients. GN patients manifested a tendency towards increase of the rate of measles virus demonstration with the rise of the titres of measles antibodies. All SLE patients with a high antibody titre (1:512 and higher) demonstrated measles virus genome. The rate of measles virus genome demonstration in GN and SLE patients did not depend on the sex, age, duration and clinical disease pattern or the content of IgA, IgM, IgG in blood serum. During disease exacerbation, the rate of measles virus demonstration was higher in 41 (59.4%) out of 69 patients than during remission--in 6 (33.3%) out of 18 patients (p less than 0.05).

[Detection of the measles virus genome in the peripheral blood lymphocytes of patients with chronic and acute glomerulonephritis]. / Vyiavlenie genoma virusa kori v limfotsitakh perifericheskoi krovi bol'nykh khronicheskim i ostrym glomerulonefritom.

The presence of the measles (rubeola) virus genome was searched for in the lymphocytes from the peripheral blood of patients suffering from the acute (16 persons) or chronic (164 persons) glomerulonephritis. Dot hybridization technique with the plasmid borne probes to the measles viral genes NP, P and H have been used for the search. The measles viral genome has been detected in 58% of lymphocytes from the patients with the chronic glomerulonephritis and in 50% of lymphocytes from the patients suffering from the acute form of the disease. The genome was not found in the material from the control group including donors and traumatology ward patients. 25 samples of lymphocytes from the patients with the chronic glomerulonephritis contained the RNA that was not hybridizable with the viral genes probes by dot hybridization technique, thus containing no genes homologous to parotitis viral genes. The average titer of anti-measles antibodies in the serum from patients with chronic glomerulonephritis the lymphocytes of which contained the measles viral genome was 1:304, while it was 1:154 for patients with the negative probes. The average anti-measles antibodies titers are the same (1:166 and 1:142) for analogical groups of patients with acute form of disease.

[Experimental measles infection in rodents]. / Eksperimental'naia korevaia infektsiia u gryzunov.

The sensitivity of newborn hamsters to inoculation with the vaccine L-16 strain of measles virus and the Lec strain isolated from a patient with subacute sclerosing panencephalitis as well as the possibility of persistence of these viruses in the animals were studied. Intracerebral inoculation of the L-15 strain was shown to produce in hamsters acute meningoencephalitis leading to death in 85%-100% of cases. Over 30 days after inoculation, the infectious virus, the virus-specific antigen and virus genome were found in the brain. In the brains of the sick animals, all the structural proteins of measles virus with the exception of hemagglutinin were expressed. After inoculation with the Lec strain, the clinical signs of the disease were less manifest, and mortality was 40%. The infectious virus could be detected in the brain up to 20 days postinoculation, the genome, up to 31 days. All the structural proteins of measles virus were expressed in the brains of the inoculated animals. No persistence of L-16 and Lec strains of measles virus could be demonstrated at langer intervals after inoculation (90-180 days) in the brains of hamsters.

Detection of measles virus genome in blood leucocytes of patients with certain autoimmune diseases.

RNA isolated from lymphocytes of peripheral blood was dot-hybridized to a hybrid plasmid containing specific sequences for measles virus nucleocapsid protein. Viral RNA was detected in the lymphocytes of 28 of 34 (82%) patients with systemic lupus erythematosus (SLE) and of 40 of 68 (59%) patients with chronic glomerulonephritis (CGN), and was not detected in 29 control patients.

[Avian CELO adenovirus as a possible contaminant in cell cultures of Japanese quail embryos]. / Adenovirus ptits CELO kak vozmozhnyi kontaminant kul'tur kletok émbrionov iaponskikh perepelov.

Avian adenovirus CELO was found to replicate poorly in Japanese quail embryos (JQE) and cell cultures of them. The infectious process in these systems was latent. The antigen of adenovirus CELO in JQE cell culture was detectable by the fluorescent antibody method (FAM) within the first 24-72 hours after inoculation as fluorescent cytoplasmic granules. Subsequently, fluorescence of nuclei and macrophage cytoplasm was observed. The results indicate that JQE and their cell cultures are not contaminated with avian adenovirus CELO despite regular circulation of this agent among avian populations. The advantages of FAM (rapidity and clearness) for identification of adenovirus as substrates contaminant as compared with other biological methods have been demonstrated.

[Analysis of the possible mechanisms for the persistence of the vaccinal strain of the measles virus in a human cell culture]. / Analiz vozmozhnykh mekhanizmov persistentsii vaktsinnogo shtamma virusa kori v kul'ture kletok cheloveka.

The mechanisms (factors) of the measles virus vaccine L-16 strain persistence in HEp-2 cell culture were analysed. Among the known mechanisms, most likely is the reduction of the cell-destroying properties of the persisting virus due to mutations in nucleoprotein gene manifested by changes of the isoelectric point of NP protein and temperature sensitivity of its synthesis.

[Electron microscopy study of the nucleocapsid structure of the measles virus isolated from cell cultures with primary and chronic infections]. / Elektronno-mikroskopicheskoe izuchenie struktury nukleokapsidov virusa kori, vydelennykh iz kul'tur kletok pri pervichnoi i khronicheskoi infektsii.

Electron microscopic examination of isolated intracellular measles virus nucleocapsids (NC) revealed a relationship between their structure, cell system, and the type of infection. Acute virus infection of Vero or Japanese quail embryo cells gave rise to the formation of linear NC strands with regularly and tightly stacked turns. Acutely infected L-41 or HEp-2 cells contained heteromorphous viral NC populations which included both typical and loosely packed NC. Persistently infected L-41 and Hep-2 cells predominantly contained NC of the latter type with the appearance of a "strings of beads".

Non-infectious morphologically altered nucleocapsids of measles virus from persistently infected cells.

Persistent measles virus infection of human HEp-2 or L-41 cells was accompanied by pronounced structural and functional changes of isolated intracellular viral nucleocapsids (NCs). The bulk of persistent NCs possessed altered conformation and a "string-of-beads" appearance, contained substantial amounts of subgenomic size RNAs, exhibited reduced transcriptase activity in vitro and lacked infectivity on transfection of susceptible cells. Immunogold staining revealed negligible binding of anti-P protein monoclonal antibodies to the "string-of-beads" type NCs, thus suggesting their non-functional state.

[Characteristics of the ribonucleoprotein of the measles virus persisting in a human cell culture]. / Kharakteristika ribonukleoproteida virusa kori, persistiruiushchego v kul'ture kletok cheloveka.

The properties of virus-specific RNPs recovered from human HEp-2 and L-41 cells chronically infected with measles virus were studied in comparison with those of RNPs formed in acute infection of L-41 cells. The persisting RNP was shown to contain nucleoprotein not differing in the electrophoretic mobility from the same protein of measles virus virions, and RNA in the persisting RNP was found to be insensitive to the action of RN-ase. RNP from chronically infected cells had a changed ultrastructure and conformation as compared with RNP of the original virus and, unlike the latter had no infectivity upon transfection of the sensitive cells by calcium-phosphate precipitation. No differences in relationships of RNP with the cytoskeleton of the infected cells in the acute and chronic infection were observed.

[Effect of elevated temperature on the persistence of measles virus vaccinal strain L-16 in a human cell culture]. / Vliianie povyshennoi temperatury na persistentsiiu vaktsinnogo shtamma L-16 virusa kory v kul'ture kletok cheloveka.

The influence of high temperature (40 degrees C) on the virus carrier state and synthesis of virus-specific macromolecules in the HEp-2 cells--measles virus system was studied. The fluorescent antibody technique showed that cultivation at this high temperature led to changes in virus antigen morphology, a decrease in the number and then complete disappearance of the cells producing virus-specific antigen. Simultaneously, gradual cessation of synthesis of all kinds of virus-specific RNA was observed in chronically infected cells. The method of radioimmunoprecipitation showed the incubation at 40 degrees C to affect first of all the synthesis of virus nucleocapsid protein. The temperature-sensitive nature of synthesis of virus macromolecules may be explained by the existence of its mutations in the genome of the persisting virus.

[Synthesis of measles virus proteins in chronically infected human cell cultures]. / Sintez belkov virusa kory v khronicheski infitsirobannykh kul'turakh kletok cheloveka.

Synthesis of measles virus proteins in primary and chronic infection of L-41 and HEP-2 cells was studied by radioimmunoprecipitation test and polyacrylamide gel electrophoresis. Synthesis of measles virus main structural proteins, H, P, NP, and M, was found to occur in chronically infected cells. Persistence of measles virus in the systems under study was shown not to be accompanied by changes in electrophoretic mobility of virus polypeptides as compared with proteins synthesized in primary infection. NP protein of the original virus, however, differed significantly from NP protein of the persisting virus in its charge which indicated aminoacid replacements apparently due to mutations of the appropriate region of the virus genome. The mechanism of measles virus persistence in these systems was shown not to be associated with disorders in matrix protein synthesis. Use of monoclonal antibodies in fluorescent antibody technique and radioimmunoprecipitation revealed the stability of a number of antigenic determinants in persisting measles virus in L-41 and HEP-2 cell cultures.

[RNA analysis of the measles virus in a human cell culture of the chronic infection]. / Analiz RNK virusa kori v kul'ture kletok cheloveka pri khronicheskoi infektsii.

Synthesis of virus-specific RNAs in human HEP-2 and L-41 cells chronically infected with measles virus was studied in comparison with synthesis of viral RNA in acutely infected L-41 cells. The RNA, a component of RNP isolated from chronically infected cells, was shown to be represented mainly by "minus" chains and to contain 23-25% "plus"-RNA. It was demonstrated by blotting hybridization that 1 species of genomic RNA with a molecular weight of 5 megadaltons was synthesized in acute infection whereas in chronically infected cells a small amount of subgenomic RNAs was additionally detected in RNP. The level of virus genome transcription in chronically infected cells was 7-8 fold lower than that in acute infection. The RNA-transcriptase activity of RNP isolated from chronically infected HEP-2 and L-41 cells was also lower than RNP activity from acutely infected L-41 cells. The observed features of virus-specific RNA synthesis in chronically infected cells seem to be likely to play a role in the maintenance of virus persistence.

[Mechanism of the cellular transformation of newborn hamsters inoculated with herpes simplex type 2 virus]. / Izuchenie mekhanizma transformatsii kletok novorozhdennogo khomiachka, inokulirovannykh virusom prostogo gerpesa tipa 2.

Combined virological, antigenic, electron microscopic, and molecular biologic study of the role of an oncovirus, herpes simplex type 2 virus (HSV-2), in the mechanisms of transformation of HSV-2-infected hamster cells was carried out. No expression of genetic information of the oncovirus could be detected. Cell transformation was shown to be associated with persistence and realization of HSV-2 genetic information in the transformed cells.

Analysis of sequences of simian adenovirus SA7 (C8) DNA in transformed rat cells and hamster tumour cells.

Different methods of molecular hybridization were used to study DNA sequences of the highly oncogenic simian adenovirus SA7 (C8) present in the genomes of two transformed rat cell lines and in cells from three hamster tumours induced by adenovirus SA7. The entire DNA or the left-hand terminal SalI C fragment (19.5% of the genome) were employed. All cell lines retained an intact left-hand region of the SA7 genome (0 to 12.4 map units). The blot hybridization technique failed to detect any site specificity of integration of SA7 DNA into the cell genome. In all cell lines the expression of the Bg/II D fragment (1.8 to 10 map units) of SA7 DNA was observed. As judged by the patterns of integration of virus sequences into the cell genome, the highly oncogenic simian adenovirus SA7 (C8) is similar to the non-oncogenic human adenoviruses of group C, and is different from the highly oncogenic human adenovirus type 12.

[Characteristics of integration of monkey adenovirus SA7 DNA fragments with genomes of transformed and tumoral cells]. / Osobennosti integratsii fragmentirovannoi DNK adenovirusa obez'ian SA7 s genomami transformirovannykh i opukholevykh kletok.

Transformed rat cells and hamster tumoral cells, obtained after treatment with DNA of monkey adenovirus SA7 which was fragmented using endonuclease SalI, contained all the SalI fragments of SA7 DNA integrated with the cell genomes. As shown by blotting hybridization distinct deletion did not form in the fragments of viral DNA on integration. Insertion of the SA7 DNA fragments appears to occur into the definite relatively small site of the cell chromosome. In the both cell strains studied a site of the SA7 genome transcribed at coordinates: 1.8-10 units of the physical map. Fragments of viral DNA were methylated in the sites CmCGG and CCmCGGG of these both strains studied.

Integration of foreign genome fragments into cells transformed or cotransformed with fragmented adenoviral DNA.

The integration of DNA of highly oncogenic simian adenovirus type 7 (SA7) and non-oncogenic human adenovirus type 6 (Ad6) into the genome of newborn rat kidney cells transformed by fragmented DNA preparations was studied using reassociation kinetics and spot hybridization. Transforming DNA was fragmented with the specific endonuclease SalI (SA7) and BglII (Ad6). In contrast to the cell transformation by intact viral DNA, transformation by fragmented DNA resulted in integration into the cellular genome of not only the lefthand fragment with the oncogene but also of other regions of the viral genome. Additionally integrated fragments were stable and preserved during numerous passages of cells lines, although they were no expressed, at least in the case of the Ad6-transformed cell line. The integration of the fragments of SA7 DNA was accompanied by loss of 25-50% of the mass of each fragment. Adding the linear form of the pBR322 plasmid to the preparation of transforming Ad6 DNA also contributed to its cointegration into the genome of the transformed cell. This technique of cell cotransformation with any foreign DNAs together with the viral oncogens may be used as an equivalent of an integration vector for eukaryotic cells.

The distribution of guanine-cytosine pairs in adenovirus DNAs.

The distribution of guanine-cytosine (GC) pairs in the DNA of the highly oncogenic simian adenovirus type 7 (SA7) and the non-oncogenic human adenovirus type 6 (Ad6) has been studied by thermal denaturation and CsC1 density-gradient centrifugation. The differential of the DNA thermal denaturation curves shows the presence of pronounced peaks which indicates uneven distribution of GC pairs along the DNA chains and the presence of regions with GC content from 30 to 74% in SA7 DNA and from 40 to 68% in Ad6 DNA. The DNA restriction fragments obtained by treatment with EcoRI, BamHI, SalI, BglII and HindIII were subjected to CsC1 density-gradient centrifugation. GC content of the fragments ranged from 45 to 70% for SA7 DNA and from 43 to 61% for Ad6 DNA. The GC content of the extreme left-hand fragments, where the transforming gene(s) is located, was higher than the average for SA7 DNA and lower than the average for Ad6 DNA. The most GC-rich regions were localized in the centre of the genome. The GC content of the right-hand part of both viral genomes was lower than the average.

Hind III restriction site map of the human adenovirus type 1 DNA.

The physical map of human adenovirus type 1 DNA was constructed with the Hind III restriction enzyme. Direct comparison of the DNA fragments with those of adenovirus type 2 revealed that the genome of adenovirus type 1 is 200 to 300 base pairs longer. The difference are located outside the region of the inverted terminal repetition within three distinct loci. Fragment Hind III-F of type 1 DNA which is presumed to carry all the genes responsible for in vitro transformation can be separated without considerable contamination by a single electrophoretic step.