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Z I Rovnova

Publications and source records attributed to Z I Rovnova.

At least 37 records · Page 2Linked to original sources
PubMedDate not supplied

[An analysis of the antigenic structure of the hemagglutinins from different strains of the influenza B virus by using monoclonal antibodies].

A comparative immunological analysis of the antigenic composition of hemagglutinin (HA) of influenza B virus drift-variants isolated during 46 years was carried out using monoclonal antibodies (MAb) to HA of B/Oregon 5/80 virus in HI test and solid-phase enzyme immunoassay. The presence of type- and group-specific antigenic determinants was demonstrated which agreed with our previous data obtained in studies with polyvalent sera. However, using Mab three more group-specific determinants were detected which characterize HA of influenza B viruses isolated in 1970-1979, 1970-1984, and 1970-1986.

Antibodies, Monoclonal↗
PubMedDate not supplied

[The use of immunoenzyme analysis in studying the etiologic structure of influenza morbidity in 1985-1988].

In the periods of epidemic increases in the incidence of influenza in 1985-1988, approximately 600 patients with clinical diagnoses of ARVI and influenza were examined for the presence of viral antigen in nasopharyngeal washings by solid-phase enzyme-immunoassay and for antibody rises in paired blood sera. The use of modified SPEIA and original test sera for influenza type A and B viruses in rapid diagnosis of influenza made it possible to decode the etiology of the epidemic situations in 1985-1988. Influenza A and B virus antigens were detected in a high portion of the examined nasopharyngeal washings. The analysis of the distribution of positive results in the detection of viral antigen in the clinical specimens and in influenza serodiagnosis demonstrated a high correlation of the results (93.9%). The etiological pattern of influenza in recent years is characterized by simultaneous circulation in the human population of influenza A (H1N1, H3N2) and B viruses, as reflected by detection of mixed infections in 1-3% of the cases.

Antibodies, Viral↗
PubMedDate not supplied

[Detection of a heterogeneous population of influenza virus type A/H1N1 with monoreceptor sera to hemagglutinin antigenic determinants].

Studies of the antigenic composition of hemagglutinins of influenza H1N1 virus variants isolated in 1981 using monoreceptor antibody to individual antigenic determinants obtained by the selective adsorption method showed some variants to represent heterogeneous populations manifesting antigenic properties of different H1N1 viruses. Passages of the heterogeneous virus in the presence of antiinfluenza serum resulted in cloning a subpopulation with the antigenic properties of the hemagglutinin similar to that of H1N1 viruses which had circulated in the end of the first period of epidemic activity of H1N1 viruses. The method "from-plaque-to-plaque" passages in MDCK cells yielded from the heterogeneous population a homogeneous variant which by the hemagglutinin antigenic properties was similar to H1N1 viruses isolated in 1956-1957.

Animals↗
PubMedDate not supplied

[New strain-specific determinants in the hemagglutinins of influenza B viruses isolated in 1983-1984].

A comparative study of sensitivity to inhibitors and antigenic composition of hemagglutinins of influenza B virus strains isolated in the epidemic season of 1983-1984 and those circulating in 1940-1981 was carried out. The method of selective adsorption of highly active rabbit and rat sera demonstrated that hemagglutinins of contemporary influenza B viruses had both common cross-reacting determinants with previously circulating variants and qualitatively different, strain-specific ones. Among the variants isolated in 1983-1984, three subgroups of viruses were detected with different strain-specific hemagglutinin determinants.

Adsorption↗
PubMedDate not supplied

[Immunological study of antigenic determinants in the isolated hemagglutinin of the influenza A virus (H1N1)].

A preparation of isolated subunits of influenza A (H1N1) virus hemagglutinin was examined for antigenic properties by four serological tests: radioimmunoassay, radial immunodiffusion test, complement fixation test, and hemagglutination inhibition test with hyperimmune polyclonal serum to intact virion as well as with monospecific antibodies to individual antigenic determinants obtained by adsorption technique. In isolated hemagglutinin subunits, radioimmunoassay identified three main virus-specific antigenic sites identical to antigenic determinants in the hemagglutinin of the intact virion. No neuraminidase was found in the hemagglutinin preparation but increased serological activity of host cell antigens was observed.

Animals↗
PubMedDate not supplied

[Immunobiological analysis of isolated subunits of influenza virus hemagglutinin].

The immunogenic properties of isolated subunits of influenza A/FM/1/47 (H1N1) virus hemagglutinin were studied. The antihemagglutinating serum was tested by the CFT, HI, competitive solid-phase radioimmunoassay, and biological neutralization test. The antiserum was found to contain populations of antibodies to the three main antigenic determinants of hemagglutinin identical to the determinants of the intact virion, as well as antibodies to the antigenic components of host cells. The antiserum to hemagglutinin as well as monospecific antibodies to individual antigenic determinants of hemagglutinin exhibited a high virus-neutralizing activity for the homologous virus.

Animals↗
PubMedDate not supplied

[Identification of the antigenic components of the host cell in isolated glycoproteins of the influenza virus].

Immunological analysis performed by solid-phase enzyme immunoassay and complement fixation test revealed the presence of host cell antigenic components in purified intact influenza virions and isolated hemagglutinins and glycoproteins. Three antigens inherent to chick embryo cells were identified in virus preparations: the species-specific antigen, heterogenetic Forssman antigen, and one similar to human group A antigen. Antisera to purified whole-virion influenza vaccines, to glycoproteins and to hemagglutinin isolated from them were found to contain antibody populations which were conducive to broad cross reactions between them and heterotypic virus antigens. To avoid erroneous results, these antibody populations must be removed from the sera by pre-adsorption with host cell antigens.

Adsorption↗
PubMedDate not supplied

[Antigenic-genetic connections between human and animal influenza viruses].

A comparative immunological analysis of the composition of antigenic determinants (AGD) in hemagglutinins of human influenza A virus (HIAV) of the serosubtypes H1, H2, H3, and in hemagglutinins of animal influenza viruses (AIV) of the serosubtypes H1, H3-H6, H8-H11 with 25 polyclonal highly active sera was demonstrated. Using original monospecific mon AGD in HIAV and AIV hemagglutinins was demonstrated. Using original monospecific antibodies to individual AGD, those AGD contributing to similarity and differences between HIAV and AIV were determined. It was found that influenza A. virus strains isolated from man in the USSR in 1986 were identical in the antigenic structure of hemagglutinin with that isolated from a tern in 1973 (A/tern/Turkmenistan/18/73).

Animals↗
PubMedDate not supplied

[Antigenic specificity of neuraminidase and structure of neuraminidase gene of influenza A(H1N1) serotype Hsw1N1 viruses isolated from man and animals].

The enzyme immunoassay and neuraminidase activity inhibition test using polyclonal and monospecific antineuraminidase sera were employed to establish the similarities and differences in the antigenic structure of neuraminidase of influenza A viruses (H1N1), serovariant Hsw1N1, isolated from man in Alma-Ata (USSR), 1984, New Jersey (USA), 1976, and Pazardjik (BPR), 1982, as well as from swine and birds. Oligonucleotide mapping revealed significant structural differences in the genes coding for neuraminidase of Hsw1N1 viruses. The experimental results indicate a high degree of the enzyme variability in this group of viruses.

Animals↗
PubMedDate not supplied

[Antigenic structure of hemagglutinins of influenza H1N1 (Hsw1N1) virus isolated from humans and ducks].

The method of specific adsorption followed by the use of antisera in HI test and competitive enzyme immunoassay was used to study the antigenic composition of hemagglutinins (HA) Hsw1 in influenza viruses isolated in 1982 from humans in Bulgaria and in 1976 in Canada from ducks as well as their antigenic relationships with HA of Hsw1 variant isolated from swine and man. Hemagglutinins of Hsw1 strains isolated from man in Bulgaria and Alma-Ata were found to be similar to HA of A/New Jersey/8/76 virus in two determinants and with hemagglutinin of the classic virus of swine in three determinants. The HA of A/duck/Alberta/35/76 virus was similar in three determinants to HA of A/New Jersey/8/76 virus and in two determinants with other Hsw1 variants. The similarities and differences in antigenic determinants of HA in Hsw1 viruses isolated from man and animals attest to their common origin and different modes of variability.

Animals↗
PubMedDate not supplied

[The use of colloidal gold-labelled antibodies for demonstrating viral antigens].

The principal possibility of using antibodies conjugated with colloid gold for better visualization of viruses, viral antigens, and their immune complexes in electron microscope was studied on the experimental model of HBs-antigen and Venezuelan equine encephalomyelitis virus. The same method was used for the study of the thin structure of influenza A (H1N1) virus hemagglutinins using monoreceptor antisera.

Animals↗
PubMedDate not supplied

[Virological and pathomorphological study of an influenzal infection in children 1982-1983].

In the interepidemic period of 1982-1983, acute respiratory viral infections and pneumonias in infants in Alma-Ata were in 40.2% of cases etiologically associated with influenza infection. In the studied period in Alma-Ata and during an epidemic outbreak of influenza in Kzyl-Orda (March, 1983), two influenza A virus subtypes, H1N1 and H3N2, were in circulation. In a number of cases these subtypes were isolated from the same infants.

Adult↗
PubMedDate not supplied

[3 cases of isolating the influenza A virus with human hemagglutinin Hsw1 in 1983 in Alma-Ata].

In the interepidemic period of late 1983 in Alma-Ata, influenza viruses with hemagglutinin of the swine subtype and neuraminidases N1 and N2 were isolated from humans. One of the strains, A/Alma-Ata/1044/83 (Hsw1N1), was isolated from the lungs of a man of 65 with the diagnosis of influenza and disseminated intravascular syndrome who had had communal and occupational contacts with swine. In paired sera of a sick child, and in seroepidemiological screening for influenza antibodies to swine influenza virus in low titres were detected in 34% of cases in subjects under 40. Radioimmunoassay of blood clots from subjects of the same focus revealed in one specimen the presence of swine influenza antigen.

Adult↗
PubMedDate not supplied

[Identification of the hemagglutinating antigens of the influenza virus by immunoenzyme analysis].

Highly active test sera detecting the presence of virus antigen both in concentrated and purified preparations and in allantoic virus cultures directly adsorbed on the solid phase have been proposed for successful identification and detection of influenza A and B virus variants. After direct sorption of purified and concentrated virus preparations, the test sera to influenza A (H1N1, H2N2, H3N2) virus detect the virus antigen in a concentration of 8 ng/ml, test sera to influenza B virus in a concentration of 40 ng/ml. After sorption on the solid phase of allantoic virus cultures the test sera detected influenza A virus antigen in a dose of 0.25-1 agglutinating units (AU), and antigen of influenza B virus in a dose of 1-2 AU.

Adsorption↗
PubMedDate not supplied

[Immunologic analysis of the antigenic properties of neuraminidase from drift-variants of influenza virus B].

The antigenic features of neuraminidases of several drift variants of influenza B virus were studied by enzyme immunoassay using antiserum to influenza B/USSR/100/83 virus neuraminidase isolated by pronase. Studies using immunosorption and competitive solid-phase enzyme immunoassay showed the presence in the antineuraminidase serum of at least two antibody subpopulations capable to inhibiting the activity of the enzyme and interacting with neuraminidase antigenic determinants: one detecting the antigenic determinant common for B/100/83 and B/Lee/40 viruses, and the other characterizing the antigenic determinant inherent in neuraminidase of B/100/83 virus and enzymes of drift variants isolated in 1970-1986 and lacking in the enzyme of B/Lee/40 virus.

Antibodies, Viral↗