[Glucose utilization in influenza of varying severity in intact or stressed animals]. / Uvoenie gliukozy na fone grippoznoi infektsii raznoi tiazhesti u intaktnykh ili stressirovannykh zhivotnykh.

Animals preexposed to stress developed manifest hyperglycemia in the first 2 days of influenza infection, which was replaced by prolonged hypoglycemia. The status of carbohydrate metabolism normalized no sooner than 3 to 4 weeks after the disease onset, although the acute phase of infection was over by the end of week 2. The changes were evident in the pattern of "sugar curve" after glucose loading. Glucose utilization failed to normalize even 2 h after the loading in animals with stress, influenza infection, or stress-associated complications of this infection.

[Formation of target cells in the immunocompetent organ (spleen) of mice with experimental infection caused by influenza A viruses with various properties]. / Obrazovanie kletok-mishenei v immunokompetentnom organe (selezenke) myshei v dinamike éksperimental'noi infektsii, vyzvannoi virusami grippa A s raznymi svoistvami.

The article presents the data on the time-course of formation of ++virus-pecific target-cells in spleens of mice infected with various types of influenza caused by a virulent viral strain and its avirulent ts-mutation. It was demonstrated that these target-cells occurred in all studied patterns of infection. Their formation turned to be of cyclic character, dose-dependent and closely related with the formation of all known mechanisms of specific and nonspecific cellular defense. The presentation pattern of viral antigens on the surface of these target-cells turned to be variable in the course of the infections evidenced their different recognition in the reactions with the participation of +virus-specific antibodies of effectual cells.

[The cellular link in the immune response in the dynamics of experimental infection caused by influenza A viruses with various properties]. / Kletochnoe zveno immunnogo otveta v dinamike éksperimental'noi infektsii, vyzvannoi virusami grippa A s raznymi svoistvami.

The development of the cell-mediated element of immunity in mice in the course of experimental influenza caused by the virulent and avirulent (ts-mutant) variants of influenza A virus was compared. The strains under test were also found to differ in their capacity for reproduction in pulmonary tissue, which could be determined for the mutant variant A/PR/8/59/1 (with 5 ts-mutations in genes P2, P3, NP, NA and M) only at an effective dose of 7.5 lg EID50. In mice infected with the initial and ts-variants of influenza A virus the formation of all mechanisms of the cell-mediated and humoral elements of immunity (natural killer activity, antitoxic T-lymphocyte activity, antibody-dependent cellular cytotoxicity, virus-specific antibodies) occurred. The curves showing the dynamics of the formation of cytotoxic mechanisms had a phasic (cyclic) character in all forms of the infectious process under study (lethal, sublethal and poorly reproductive). A dose-dependent effect on the character of the formation of these mechanisms was registered; besides, at the later period of observation (till day 14) the presence of activity was noted when the infectious virus was not detected, which may serve as an additional evidence of the prolonged expression of the viral genome in the body of the host.

[Methodologic approaches to assessing cellular protection in influenza (the model: splenocyte versus splenocyte)]. / Metodicheskie podkhody k otsenke kletochnoi zashchity pri grippe (model': splenotsit protiv splenotsita).

To study the cell-mediated link of immune response in mice in experimental influenza, both spleen cells obtained from intact mice and infected with the virus in vitro and spleen cells obtained from infected mice on day 6 after infection may equally be used with success as target cells. This opens the possibility of studying the role of virus-specific modifications of the cell membranes of immunocytes in the pathogenesis of influenza infection. The use of effector cells without their additional stimulation with homologous virus in vitro permits the simultaneous study of different mechanisms of specific (cytotoxic T lymphocytes and antibody-dependent cell-mediated cytotoxicity) and nonspecific (natural killer cells) cell-mediated immunity developing in influenza, as well as the study of the functional activity of spleen cells under the conditions similar to those existing in the body when the duration of the experiment is 5-7 days shorter.

[Fatal synergism of viral-bacterial infections (a model of influenza-streptococcal infections)]. / Leta'lnyi sinergizm virus-bakteria'lnykh infektsii (mode'l: gripp-streptokokk).

A model of virus-bacterial infection involving A (PR-8/34) influenza virus and group B streptococcus is proposed to demonstrate the cyclic manifestations of fatal synergism of the causative agents correlating with either the cyclic detection of influenza virus antigens in the infection focus on administration of avirulent streptococcal Fos4 strain, or with the time-course of activity shown by natural killers on administration of virulent streptococcal Fos8 strain. Based on the presented data on the cyclic character of fatalities, whose dynamics varies only slightly with the biological properties of the second agent, a conclusion has been derived on (1) the simultaneous influence of various factors in the formation of the mechanisms of infection transformation, (2) the capability of the cell receptor apparatus to respond to an external stimulus which is the most important of these mechanisms, and (3) the effects of the biological properties of the causative agents on the fatal effect manifestations.

[Characteristic features of experimental influenza in mice--long-term presence of viral antigens in the spleen]. / Kharakternaia cherta éksperimenta'lnogo grippa u myshei--dlite'lnoe prisutstvie antigenov virusa v selezenke.

The process of long-term preservation of virus antigens outside the main infection focus, which is currently one of the most topical problems, has been studied. The virus antigens were found to be present in the spleen of F1/CBA X C57Black/6 mice during 4-5 weeks following their infection with A/PR/8/34/HIN1 influenza virus. Immunoblotting assay findings showed hemagglutinin, a large hemagglutinin subunit, and a protein of the influenza virus nucleoprotein to be present in the splenocytes. The antigen-carrier splenocytes are target-cells in the reaction of antibody- and complement-dependent cytotoxic lysis and also for the effectors of natural and virus-specific cell-mediated cytotoxicity during no less than 14 days. This is an indirect evidence of the membranous localisation of the virus antigens.