[Immunity indices of mice immunized with different vaccines against Japanese encephalitis]. / Pokazateli immuniteta u myshei, immunizirovannykh razlichnymi vaktsinami protiv iaponskogo éntsefalita.

The test of adoptive transfer of immunity demonstrated that in the mice vaccinated with inactivated Japanese encephalitis vaccines the protective activity to the homologous virus is provided predominantly by B-lymphocytes the protective effect of which is enhanced by cooperative interaction with T-lymphocytes. The culture (CV) and purified brain (BV) vaccines induce high levels of humoral and cell-mediated immunity, however, the capacity of CV to produce antibody is higher than that of BV. Both preparations do not cause in vaccinated mice any changes in responsiveness to extraneous antigen (sheep red cells), or disorders in chemotaxic mobility of leukocytes and phagocytic activity of macrophages.

[Donor immunization with an inactivated concentrated purified vaccine against tick-borne encephalitis to obtain immune blood preparations]. / Immunizatsiia donorov inaktivirovannoi kontsentratrirovannoi ochishchennoi vaktsinoi protiv kleshchevogo éntsefalita dlia polucheniia immunnykh preparatov krovi.

Vaccination of seronegative and seropositive donors with a concentrated purified vaccine (CV) against tick-borne encephalitis induced antibody synthesis in a concentration sufficient for preparation of donor immunoglobulin with antibody titres of 1:320 to 1:1280 by HI test. The resulting preparation showed a high antiviral activity both in vivo and in vitro against antigenically different strains of tick-borne encephalitis virus. The immune plasma derived from CV-immunized donors had a therapeutic effect in patients with tick-borne encephalitis. The optimal schedules for immunization of donors are discussed.

[Reactogenicity and immunological effectiveness of a concentrated, purified vaccine against tick-borne encephalitis]. / Reaktogennost' i immunologicheskaia éffektivnost' kontsentrirovannoi, ochishchennoi vaktsiny protiv kleshchevogo éntsefalita.

Human reactogenicity and immunological efficacy of concentrated purified tick-borne encephalitis (CTBEV) vaccine was studied in a controlled trial. The new vaccine was found to be superior to the commercial preparation in its capacity to induce specific humoral and cell-mediated immunity in man and in reduced sensitizing activity with regard to nonviral cellular antigens. Two vaccinations with CTBEV in doses of 0.5 ml each at 6-month interval are recommended. At this vaccination schedule virus neutralizing antibodies were detectable in 95% vaccines. Inoculation of 0.5 ml CTBEV is accompanied by fever of mild and moderate intensity in 19% and 3% of the vaccines, respectively. In this respect CTBEV is less reactogenic than the commercial preparation.

[Inactivated vaccine against Japanese encephalitis. The characteristics of a purified preparation from mouse brain]. / Inaktivirovannaia vaktsina protiv iaponskogo éntsefalita. Kharakteristika ochishchennogo preparata iz mozga myshei.

A vaccine has been prepared from formalin-inactivated suspension of brain tissue of Japanese encephalitis (JE) virus-infected white mice. The material was purified by flow ultracentrifugation in sucrose density gradient. Four members of the Nakayama antigenic group were compared as production JE virus strains for the vaccine preparation. Satisfactory results with regard to the immunogenicity of the bulk vaccine determined in mice (the intensity of response and the antigenic spectrum range) were obtained for three of them, including only one of the two variants of the Nakayama NIH strain. The highly purified experimental vaccine proved to be immunologically active and safe in trials in laboratory animals and 20 human volunteers. After two vaccinations, immunological changes in people were recorded much more frequently in the neutralization test than in the hemagglutination-inhibition test. Blasttransformation of lymphocytes in response to the specific antigen was observed in 5 out of 7 vaccines examined. There was no strict correlation of this test with the results of both serological tests.

[Immunological status of people inoculated with various types of inactivated vaccine against tick-borne encephalitis]. / Immunologicheskii status liudei, privitykh razlichnymi tipami inaktivirovannoi vaktsiny protiv kleshchevogo éntsefalita.

As compared with cellular immunity tests, serological tests more frequently detect virus-specific immune response in humans immunized with concentrated purified vaccine (CV) against tick-borne encephalitis. Combined determination of cell reactions and antibody production after a single injection of the vaccine increases the rate of detection of specifically responding persons. The duration of the inactivated vaccine-induced immunity is determined not only by the level of serum antibodies but also by the state of immunological memory detectable by the capacity of the host to produce antibodies after another injection of the specific antigen. At 14 and 30 days after a single immunization with CV IgG antibody is found in the blood of the vaccinees. In the course of 3 vaccinations, the concentration of serum immunoglobulins, chemotaxic activity of leukocytes, and blood lymphocyte reactivity to mitogens do not change. The role of some immunological values as criteria for the evaluation of the effectiveness of vaccine purification from impurities is discussed.

[Concentrated purified vaccine against tick-borne encephalitis. An immunological evaluation in experiments on mice]. / Kontsentrirovannaia, ochishchennaia vaktsina protiv kleshchevogo étsefalita. Immunologicheskaia otsenka v opytakh na myshakh.

Comparative investigations of the immunological activity of two inactivated vaccines against tick-borne encephalitis, concentrated and commercial ones, were carried out. Higher levels of humoral and cellular immune responses were achieved after inoculation of the concentrated vaccine. Both vaccines did not affect the general immunological responsiveness of the animals.

[Immunological indices of human vaccination against tick-borne encephalitis using inactivated preparations with a varying concentration of the viral antigen]. / Immunologicheskie pokazateli vaktsinatsii liudei protiv kleshchevogo éntsefalita inaktivirovannymi preparatami s raznoi kontsentratsiei virusnogo antigena.

The results obtained in the determination of the immunological activity of 3 types of formalin-killed tissue-culture tick-borne encephalitis vaccine, commercial non-concentrated and concentrated by 2 different methods, in humans are presented. Judging by the data of 3 serological tests and the blast transformation test, the concentration of killed tick-borne encephalitis virus enhanced immune response to vaccination. The intensity of this response correlated with the mouse protection capacity of the vaccine batches under test. An increase in the content of viral particles in the preparation is considered to be a promising approach to enhancing the effectiveness of vaccination against tick-borne encephalitis.

[Intratypical antigenic differentiation of poliovirus strains circulating in Mali by means of cross-adsorbed sera]. / Vnutritipovaia antigennaia differentsiatsiia tsirkuliruiushchikh w Mali shtammov virusa poliomielita s ispol'zovaniem perekrestno-adsorbirovannykh syvorotok.

The intratypic antigenic differentiation of poliovirus strains isolated from sick or healthy children in Mali in 1975-1976 was performed. The method is based on the use of cross-adsorbed sera in the neutralization tests in which the virus is titrated by the plaque procedure or by the cytopathic effect. All the examined strains of serologic types I, II, and III were distinguished by the antigenic structure from the vaccine strains and were classified as "wild". Quantitative differences in the antigenic structure of type I strains isolated in different towns of Mali were found.

[Use of cross-absorbed sera in neutralization tests with viral titration by the cytopathogenic effect]. / Ispol'zovanie perekrestno adsorbirovannykh syvorotok v reaktsii neitralizatsii s titrovaniem virusa po tsitopatogennomu deistviiu

A new method for intratypic antigenic differentiation of poliovirus strains has been developed. The method is based on the use of cross-absorbed sera in neutralization tests where virus is titrated by the cytopathic effect. Qualitative differences between the antigenic structure of vaccine and "wild" strains as well as between some "wild" strains of the same serologic type have been found. The method may be used in practical laboratories.