California serogroup viruses from mosquitoes collected in the USSR.

Four California serogroup viruses isolated from mosquitoes in the USSR were tested for antigenic analogy with prototype viruses of the California serogroup. The topotype isolates are biologically similar to, but antigenically different from each other. One is a subtype of snowshoe hare virus, two are different subtypes of Tahyna, Lumbo, and snowshoe hare viruses, and one is identical to Inkoo virus, previously isolated only in Finland. The results indicate that molecular studies of these viruses are necessary to comprehend their evolution.

Identity of Karelian fever and Ockelbo viruses determined by serum dilution-plaque reduction neutralization tests and oligonucleotide mapping.

The causative agents of Ockelbo disease in Sweden, Pogosta disease in Finland, and Karelian fever in the USSR have been attributed to alphaviruses (family Togaviridae) related to Sindbis virus. We compared prototypes Sindbis, Ockelbo, and Karelian fever viruses by neutralization tests. We also analyzed oligonucleotide fingerprint maps of prototypes Ockelbo and Karelian fever viruses and a strain of Sindbis virus from Czechoslovakia. The results indicate that Ockelbo and Karelian fever viruses are essentially identical and suggest that Ockelbo disease, Pogosta disease, and Karelian fever are synonyms for the same disease.

[Physicochemical properties of the RNA and proteins of an influenza virus H1N3 isolated from an ill child and antigenically analogous to A/whale/TO/19/76]. / Izucheniefiziko-khimicheskikh svoistv RNK i belok virusa grippa H1N3, izolirovannogo ot bol'nogo rebenka i antigenno analogichnogo virusu A/kit/TO/19/76.

A comparative analysis of RNA and proteins of influenza A/Baku/799/82, A/whale/TO/19/76, and A/PR8/34 viruses was carried out. The viruses were shown to be similar in their polypeptide composition and oligopeptide maps of the heavy (HA1) and light (HA2) chains of hemagglutinin; in their migration properties of RNA fragments in polyacrylamide gel the A/Baku/799/82 and A/whale/TO/19/76 viruses were similar but not identical. Marked differences in the electrophoretic mobility in gel of RNA fragments coding for P proteins, HA, NP, and NA polypeptides were demonstrated. All these fragments of A/whale/TO/19/76 virus had higher electrophoretic mobility in gel. RNA fragments coding for M and NS proteins had a similar electrophoretic mobility. The A/Baku/799/82 and A/whale/TO/19/76 viruses differed considerably in migration properties of the RNA fragment coding for neuraminidase from the epidemic A/PR8/34 virus. In the latter, this fragment had a higher electrophoretic mobility in gel. Experiments of RNA-RNA hybridization demonstrated a high degree of homology of the primary structure of all RNA fragments of A/Baku/799/82 and A/whale/TO/19/76 viruses.

[Oligopeptide mapping of the proteins of animal influenza virus nucleoproteins]. / Oligopeptidnoe kartirovanie belkov nukleoproteidov virusov grippa zhivotnykh.

Oligopeptide mapping showed the viruses H1N1 and H3N2 isolated from animals, unlike the majority of animal viruses with "animal" subtypes of the surface antigens, to have NP proteins typical of human H1N1 and H3N2 viruses which confirms their origin from human viruses.

[Comparative study of the polypeptide composition of influenza A viruses sensitive and resistant to remantadine]. / Sravnitel'noe izuchenie polipeptidnogo sostava virusov grippa A, chuvstvitel'nykh i rezistentnykh k remantadinu.

The polypeptide composition of influenza A FPV (Hav1N1) and A/Texas/1/77 (H3N2) viruses which had acquired resistance to remantadine after serial passages in cell cultures in the presence of the drug was studied. It was found that in parallel with the acquired resistance to remantadine the molecular weight of the heavy chain of hemagglutinin changed only in the course of cell culture passages. The influenza A/Texas/1/77 virus passaged in chick embryos in the presence of remantadine exhibited no differences in the electrophoretic mobility of hemagglutinin between the sensitive and resistant variants. Remantadine is assumed to be an additional factor which influenza virus has to overcome in the process of adaptation to cell cultures.

[Variability of hemagglutinin and nucleoprotein proteins in the "Spanish" series of influenza viruses]. / Izmechivost' belkov gemagglutinina i nukleoproteida u virusov grippa "ispanskogo" riada.

Oligopeptide mapping and immunological methods were used to study influenza viruses of the evolutionary series Hsw1-H0-H1 isolated from man and animals. Among the animal viruses some possess hemagglutinins similar to those observed in the viruses isolated from man, while some viruses differ from them. These are assumed to be precursors of the viruses of "Spanish" influenza retained in animals. Variability of the nucleoprotein protein in the viruses under study was observed.

[Comparative study of the RNA and proteins of antigenically similar human and animal influenza A viruses]. / Sravnitel'noe izuchenie RNK i belkov antigenno skhodnykh virusov grippa A zhivotnykh i cheloveka.

In 1976-1979 in various regions of the USSR influenza viruses were isolated from mammals and birds and found to be antigenically similar with human influenza viruses having hemagglutinin H0, H1, and neuraminidase N1. Comparative studies of electrophoretic mobility in polyacrylamide gel of RNAs and proteins of these viruses and human influenza viruses sharing common antigens with them were carried out. By the mobility in gel of genome fragments, the virus isolated from a squirrel, A/squirrel/Vladivostok/1004/79 (H0N1), was found to be similar to human A/PR/8/34 (H0N1) virus; both viruses had a similar polypeptide composition. In contrast, the virus isolated in 1978 from a turkey, A/turkey/Kiev/292/78 (H1N1), by the mobility in gel of genome fragments including those coding for hemagglutinin and neuraminidase differed significantly from antigenically similar epidemic viruses: A/FM/1/47/ (H1N1) and a virus isolated during an epidemic in the same year, A/USSR/90/77/ (H1N1) despite the similarity with the latter in the polypeptide spectrum. Hemagglutinin of a virus isolated in 1976 from blue whales, A/whale/TO/19/76, was serologically identified as HO, neuraminidase of this virus as Nav2. An analysis of genome fragments of the whale virus showed the gene 4 coding for hemagglutinin to be similar by mobility in gel with the corresponding fragment of human influenza virus A/PR/8/34 (H0N1), and the gene 6 coling for neuraminidase in most influenza A viruses to be similar by mobility in gel with the gene 6 of A/pintail/Primorie/695/76 (H2Nav2) virus. An analysis of proteins of this virus by mobility in gel showed all its proteins, with the exception of one with a molecular weight of about 70,000 daltons, to be similar with those of human A/PR/8/34 (H0N1) virus. The protein with the molecular weight of about 70,000 daltons is assumed to be neuraminidase of the second avian type (Nav2). A similar protein was found in avian viruses A/pintail/Primorie/18/76 (H2Nav2), and A/tern/Turkmenia/18/73 (Hav7 Nav2). The antigenic analysis of these strains using a panel of 6 monoclonal antibody to the A/Brazil/11/76 (H1N1) strain revealed a close similarity in the antigenic structure of hemagglutinin of human influenza virus A/USSR/90/77 (H1N1) which had caused an epidemic outbreak in the USSR in 1977-1978 and A/turkey/Kiev/292/78 (H1N1) virus. Human and animal influenza viruses with hemagglutinin of the HO type did not react with any of the 6 clones under study.

[Properties of Hav6Neq2 and Hswl(H0)Hav2 influenza viruses isolated from waterfowl in southern Turkmenia]. / Svoistva virusov grippa Hav6Neq2 i Hswl(H0)Hav2, izolirovannykh ot ptits okolovodnogo kompleksa na iuge Turkmenii.

Three influenza A virus strains were isolated from shorebirds in October, 1977, in southern Turkmenia, in the vicinities of Tedzhen water reservoir. From a common tern, A/Sterna hirundo/Turkmenia/45/77 strain was isolated with the antigenic formula Hav6Neq2, from a teal and a black-headed gull influenza A/Anas crecca/Turkmenia/4/77 and A/Larus ridibundus/Turkmenia/13/77 strains with previously unknown combination of surface antigens Hswl(H0)Nav2 were recovered. By the molecular weight of the heavy (HA1 59,000 d) and light (HA2 24,000 d) chains of hemagglutinin, the Turkmenian viruses A/Larus ridibundus/Turkmenia/13/77 and A/Anas crecca/Turkmenia/4/77 are similar to each other and to the strains having H0 hemagglutinin: A/PR8/34 (H0N1) and A/Whale/PO/19/76 (H09Nav2). The Turkmenian viruses are characterized by a low content of the light hemagglutinin chain (HA2) which is typical of the viruses with Hsw1 hemagglutinin: A/New Jersey/8/76 (Hsw1N1) and A/SW/Wisk/68 (Hsw1N1).

[RNA-synthesizing complex of the Sendai virus in the nucleoli of infected Erlich ascitic carcinoma cells]. / RNK-sinteziruiushchii kompleks virusa Sendai v iadryshkakh zarazhennykh kletok astsitnoi kartsinomy Erlikha.

A virus-specific complex with sedimentation constant of 250S and buoyant density 1.35 g/cm3 in cesium chloride density gradient is formed within 20--24 hours after infection in nucleoli of Ehrlich ascitic carcinoma cells infected with Sendai virus. The complex contains a rapidly sedimenting RNA (70--90S) which is about 50% stable to RN-ase. The complex has RNA-polymerase activity in a cell-free system; the product of the RNA-polymerase reaction is a RNA with sedimentation constant 50S. It is suggested that the virus-specific structure with sedimentation constant 250 S found in nucleoli is the Sendai virus replicative complex.

[Localization of genome RNA synthesis in Sendai virus]. / Lokalizatsiia sinteza genomoi RNK virusa Senadai

Localization of Sendai virus 50S RNA in Ehrlich ascitic carcinoma cells was studied. At 48 hours postinfection virus-specific 50S RNA was found in the nucleus after 30 min exposure to 3H-uridine, and its amount increased after 1-hour exposure to the precursor reaching 18% of the total nucleus virus-specific RNA. After 2-hour or longer exposure to the precursor the amount of 50S RNA in the nuclei decreased considerably and in the cytoplasm in this gradient region a considerable radioactivity appeared. Rapid utilization of 3H-uridine by the cells under these experimental conditions suggests that 50S RNA is synthesized in the nucleus and migrates to the cytoplasm.

Characteristics of Sendai virus RNA transcriptive complex formed in the cytoplasm of infected ascites cells.

Virus-specific structures with sedimentation coefficients of 250-300, 200 and 150 S were isolated from the polysome fraction of Sendai virus-infected Ahrlich ascitic carcinoma cells treated with cycloheximide, at early stages of infection (1.5 to 2 hours after inoculation). All these 3 types of structure contained both parental and newly synthesized viral RNA. RNA extracted from these structures consisted of 2 components sedimenting in sucrose density gradients in the zones of 50-70 and 35-40 S. Both components contained parental and newly synthesized RNA and were partially resistant to ribonuclease. RNA extracted from rapidly sedimenting structures (250-300 S) contained mainly the 50-70 S component; RNA recovered from 200 S structures contained the 35-40 S component. By analogy with reported data, the isolated forms of RNA have been characterized as transcriptive intermediates.