[Efficacy of combined administration of ridostin and oseltamivir (tamiflu) for therapy and prophylaxis of experimental infection induced by influenza virus A (H5N1) in mice]

AIM

Study of possibility of treatment-prophylaxis effect increase during combined administration of ridostin and tamiflu in experiments in mice infected with highly pathogenic influenza virus strain A/chicken/Kurgan/05/2005 (H5N1).

MATERIALS AND METHODS

Balb/c line mice infected intranasally with influenza virus at 100 and 10 LD50 doses received ridostin and tamiflu as monopreparation or the combined variant before or after the infection. The mice were observed for 16 days, lethality rate, protection coefficient and average life span were evaluated. Virus concentration in lungs was determined by using titration in MDCK cell line.

RESULTS

Combined administration ofridostin and tamiflu after the infection increased survivability of the animals when compared with the control group, and reduced influenza virus concentration in lungs.

CONCLUSION

Treatment effect during combined administration of ridostin and tamiflu after influenza virus infection increased.

[Biological properties of a prolonged action interferon inductor]

AIM

Evaluation of composite formulation of yeast double stranded RNA with polyglucinum (dsRNA-PG) effect on non-specific antiviral resistance factors in mice in comparison with commercial formulation Ridostin.

MATERIALS AND METHODS

dsRNA and Ridostin formulations were injected intramuscularly once at the dose of 5 mg/ml, polyglucinum--at the dose of 3.75 mg/ml. 3, 5, 24, 48 and 72 hours after the injection serum interferon levels, neutrophil oxidation-reduction activity parameters, peritoneal macrophage phagocyte activity levels were analyzed in mice blood samples.

RESULTS

New dsRNA and polyglucinum containing composite formulation is a non-specific resistance system stimulator. dsRNA-PG effect on interferon synthesis and mice phagocyte activity was higher than with Ridostin and developed earlier. Neutrophil function activation by the formulation had a prolonged effect. A possible explanation for increased activity of dsRNA and polyglucinum composite formulation is a modulating effect by the polysaccharide component.

CONCLUSION

The new formulation may have a more intensive and prolonged protective effect against influenza virus in comparison with Ridostin.

[Antitumor properties of a liposomal form of a differentiation factor HLDF fragment in cultured cells]

Cytotoxic properties of a liposomal form of the HLDF6 hexapeptide, representing an HL-60 cell differentiation factor fragment, have been studied on a murine primary lymphosarcoma cell culture. It is established that the liposomal HLDF6 peptide is capable of inhibiting proliferation and enhancing death of the cells of both LS and RLS lymphosarcoma strains distinguished by their sensitivity to cytostatic agents. The effect of the preparation is determined by its antiproliferative and apoptogenic actions on the cells. Free HLDF6 peptide showed a lower cytotoxic activity with respect to the tumor cells as compared to the liposomal preparation.

[Investigation of antitumor activity of the hexamer fraction of HLDF-6 peptide as a differentiation factor in hemoblastoma-bearing mice]

A study of antitumor properties of HLDF-6 was carried out in DBA/2 mice with transplantable ascites lympholeukemia P-388 as well as in tumor cell culture. Immunomodulating characteristics were evaluated. Five-fold administration of HLDF-6 peptide to tumor-bearing mice inhibited tumor growth thus extending survival. As a result metabolic activity decreased which was followed by longer survival of lympholeukemia P-388 cells and enhanced cytological effect of peritoneal macrophages on tumor cells of the same strain.

Combined virus-like particle-based polyepitope DNA/protein HIV-1 vaccine design, immunogenicity and toxicity studies

We have previously described designing of polyepitope immunogens TBI and TCI, to stimulate the humoral and cellular immune responses to HIV-1. Here, immunogens TBI and TCI were used to create new vaccine construct named CombiHIVvac (Combined HIV-1 vaccine). CombiHIVvac is a virus-like particles (VLP) containing the DNA vaccine pcDNA-TCI as a core encapsulated within a spermidine-polyglucin-TBI conjugate. The immunogenic and toxic properties of the candidate vaccine CombiHIVvac have been studied. CombiHIVvac induces a strong humoral and CTL responses in mice; the antibodies are highly specific and are able to neutralize HIV-1 in vitro. Preclinical study demonstrated that CombiHIVvac does not cause long-term changes in physiological, biochemical and morphological parameters in immunized animals and thus can be recommended for clinical trials.

Effect of Granulocyte Colony-Stimulating Factor on Myocardium Recovery in Postinfarction Period

The effect of Neutrostim (preparation of granulocytic colony-stimulating factor) on recovery of myocardial tissue after acute myocardial infarction was studied in rats. A course of Neutrostim after ligation of the left coronary artery led to normalization of electrocardiographic and morphological parameters of the myocardium after one month.

[Results of Befnorin clinical trails in healthy volunteers]

Clinical trails of Befnorin based on the human recombinant TNF-beta elaborated at the Research Design and Technology Institute of Biologically Active Substances, "Vector" State Research Center of Virology and Biotechnology, were carried out on healthy volunteers in compliance with a decision passed by the Committee of Medical and Immunobiological Preparations, Russia's Health Ministry. Single Befnorin doses of 5-10(4) U, 10(5) U, 5-10(5) U, and 10(6) U were administered as intramuscular injections. Clinical, biochemical and immunological parameters were registered for 7 days after a single dose. The drug had an impact on the below immunity indices: Fc-phagocytosis of monocytes, migration index and migration inhibition index. The dose of 10(5) U was proven to be most effective and safe. Supposedly, the drug can be effective in the treatment of herpetic diseases.

[Effects of the dsRNA interferon inducer on the interaction between macrophages and Mycobacterium tuberculosis in vitro]

Effects of the IFN inducer, yeast dsRNA, produced on the interaction between mouse macrophages and phagocytized mycobacteria were experimentally studied in vitro. Mycobacteria were shown to reproduce in macrophages in their initial infection at a ratio of 1:1.25, 1:2.5, 1:5 and 1:10, which was confirmed by an increased insertion of 5.6-[3H]-uracil in M. tuberculosis H37Rv; they also had a destructive impact on macrophages as verified by a higher release of lactic dehydrogenase (LDG) from macrophages. The dsRNA preparation, 40.0, 80.0 and 120.0 microg/ml, was demonstrated to decrease the insertion amount of labeled uracil in phagocytized mycobacteria at a macrophage:mycobacteria ratio of 1:10 and 1:100. The effect depended on a preparation dose and infection degree of macrophages. A decreased release of specific LDG from infected macrophages was shown under the same conditions. The dsRNA affects the interplay of macrophages and phagocytized mycobacteria through inhibiting the vitality of intracellular mycobacteria and through enhancing the stability of macrophages. Special studies denoted that dsRNA, 40.0 microg/ml and 120 microg/ml, activated the production of peroxidation compounds by neutrophils, which phagocytized the sheep erythrocytes. Finally, a possible mechanism of dsRNA impact on the interaction between macrophages and mycobacteria phagocytized by them is under discussion.

[Designing of a liquid serum panel containing or not class IgG antibodies specific to human cytomegalovirus]

Designing of a liquid serum panel for the determination of class G antibodies specific to human cytomegalovirus (HCMV) is under discussion. Sera were selected by ELISA for antibodies to HCMV and by PCR for CMV DNA. The serum panel comprises samples of positive and negative sera with high and low titers. Sera were stabilized by a stabilization solution. The panel shelf life was evaluated by routine methods and by the "accelerated aging" technique. Sera selected for a standard panel containing or not antibodies to HCMV preserve their properties and stability for as long as 1 year at 4 degrees C.

[Outlooks for using the interferon inducers in the treatment and prevention of influenza and acute respiratory viral diseases]

The methods of treatment by using the stimulators of the non-specific resistance system have been growing even more topical. Drugs based on interferon (INF) and its inducers belong to the group. IFN is of key importance in the regulation of antiviral immunity. The use of IFN inducers can be referred to as the most promising approach to enhancing and activating the body resistance mechanisms. The advantages of IFN inducers before IFN drugs, a wide spectrum of antiviral effects, compatibility with many pharmaceuticals, good tolerability by patients and effectiveness in different administration modes served as a basis for designing a new class of antiviral drugs--IFN inducers. A lot of experimental medical-and-biological research was made to evaluate the efficiency of IFN inducers in influenza. They were shown to possess a pronounced therapeutic-and-preventive action in experiment and clinical trials. Synthetic and natural dsRNA belong to IFN inducers. Multiple research made in cell culture and with experimental animals demonstrated a high interferon-inducing and antiviral activity of double-stranded RNA against influenza virus. A number of dsRNA-based IFN inducers are permitted for clinical use. Data obtained in clinical trials of such inducers are indicative of their pronounced therapeutic-and-clinical effect. Hence, the IFN inducers having different structures and origins can be regarded as promising in the treatment and prevention of influenza and acute respiratory viral diseases.

[The impact of compound of double-stranded RNA and hyaluronic acid on the parameters of non-specific resistance in mice]

The effect of yeast double-stranded RNA (dsRNA) and of hyaluronic acid (HA) compositions produced on the interferon synthesis, peritoneal phagocytic activity of macrophages and on the hematological parameters were studied in an experiment with white noninbred mice. HA was shown to enhance the dsRNA-induced interferon synthesis, to inhibit the leukopenic reaction and to produce no effect on the phagocytosis-stimulating activity. The data obtained are indicative of that HA is a promising preparation regarding its use within the interferon-inducing compositions based on dsRNA.

[Effect of tumor necrosis factor alpha on the efficiency of anti-rabies vaccination]

Recombinant tumor necrosis factor-alpha (TNF-alpha) improved the survival of random-bred albino mice vaccinated with antirabies vaccine after infection with rabies CVS strain. The agent dose of 0.1 microgram/animal, injected 1 day postvaccination, was the most effective. Improvement of antiviral resistance of non-vaccinated mice under the effect of TNF-alpha suggests that the effect of this factor on nonspecific resistance factors is one of the probable mechanisms of its modulating effect.

[Study of the antiviral activity, pharmacokinetics and toxic properties of liposomal form of human alpha-2b interferon administered topically]

Human liposomal recombinant alpha 2b-interferon topically applied to laboratory animals was tested for antiviral activity, pharmacokinetics, and toxicity. The interferon was shown to penetrate through the skin and to circulate in the blood of experimental animals longer than its injectable form, and to exhibit its antiviral activity against genital herpes in guinea pigs. It produced no toxic, skin-irritant, or allergic effects in laboratory animals.

[Photoinactivation of microorganisms in the presence of photosensitizers]

Two photosensitizing preparation for the photodynamic therapy of oncological diseases have been obtained. As revealed in this study, under experimental conditions their action suppresses the growth of Enterococcus faecalis and Staphylococcus aureus, which may be of great importance for the treatment of infections. And in contrast to antibiotic therapy, their use may not affect the development of normal intestinal microflora. The study has shown that their derivatives with the residues of carbonic (or muramic) acids more intensively penetrate microorganisms through their cell walls. This makes in possible to expand the spectrum of action of the preparations. The proposed method permits the rapid analysis of the photochemical activity of preparation for photodynamic therapy in the process of their development.

[Effect of human recombinant granulocyte colony-stimulating factor on mouse hematopoietic and lymphoid organs]

Experiments on intact CBA/CALac mice demonstrated that single (1.25 mg/kg) and repeated (0.125 and 1.25 mg/kg, 30 days) injections of recombinant human granulocyte colony stimulation factor lead to reversible dose-dependent granulocyte lineage hyperplasia in bone marrow, regenerative neutrophilic leukocytosis, and thrombocytosis in peripheric blood and to splenic granulo-, erythro-, and thrombocytopoiesis more expressed in males.

[The activation of phagocytosis by recombinant human tumor necrosis factor-beta]

The functional activity of phagocytic cells of various types was studied in white non-inbred mice by administering recombinant human tumor necrosis beta (rhTNF-beta). It was shown that rhTNF-beta increased phagocytic activity of the peritoneal exudate, spleen and liver macrophages as well as blood polynuclears. Stimulation of neutrophils was demonstrated in earlier times after administration of the preparation as compared to macrophages (3 h and 24 h, respectively). The duration of the macrophage activation effect and its expression depended on the dose of the preparation and were the most notable when rhTNF-beta was administered in doses of 10(3)-10(5) U/20 g. The addition of reopolyglucin, the polysaccharide filler, didn't remove a stimulatory effect of rhTNF-beta on macrophages, but influenced its dynamics. Multiple administration of the preparation didn't cause the phagocytosis stimulation effect.

[The immunoregulatory properties of recombinant human tumor necrosis factor-beta in mice opposite-reacting to antigen]

The effect of 10(3)-10(5) E/20 g doses of the recombinant factor of human beta tumor necrosis (rFNT-beta) on formation of the immune response and macrophage functional activity was studied in CBA and C57Bl/6 mice that differ in genetically determined level of the immune response to an antigen (sheep erythrocytes). The rFNT-beta was found to cause a modulating effect on the cell and humoral links of the immune response. The effect of the agent depended on the dose and the genotype of the experimental animals. It is suggested that the interlinear differences in the intensity of the humoral immune response in rFNT-beta administration may be connected with the different sensitivity to the agent of the peritoneal macrophages of mice of the used lines.

[The blood-simulating properties of a recombinant colony-stimulating factor and glycyram during cytostatic myelosuppression]

The hemostimulating activity of the drug glycyrram and the recombinant granulocytic-macrophagic colony-stimulating factor (CSF) was compared on models of myelosuppression induced by injection of an alkylating agent cyclophospane (CF) or the antimetabolite 5-fluorouracil (5-FU). It was found that glycerram stimulated hematopoiesis more effectively after 5-FU injection but to a lesser extent (in relation to CSF) in CF injection.

[Experimental study of therapeutical properties and safety of king crab collagenase-containing ointment]

The effects of ointment containing king crab (Paralithodes camtschatica) collagenase on intact skin, thermal, and pyonecrotic wounds were studied in rats by using hematological, biochemical, immunological, and morphological methods. The ointment for the skin and viscera was shown to be safe. It is highly effective in debriding the infected wounds. Different concentrations of collagenase were tested. The concentration of collagenase was recommended to be 0.2 mg/g ointment for use.

[Dynamics of interferon induction in albino mice by interferon inducer ridostin administered by various routes]

The time dependence of interferon production in blood, tissues of the respiratory tract, brain and olfactory tract of mice BALB/c was investigated after administration of the interferon inductor ridostin by various routes. Intraperitoneal injection of ridostin in a dose of 5 mg/kg induced intensive accumulation of interferon in the blood serum with the peak in 8 hours (2560 U/0.2 ml) while no interferon was detected in the tissues of the respiratory tract and brain of the animals. Intracerebral injection of ridostin in the same dose induced accumulation of interferon in both the tissues of the brain (maximum 160 U/0.2 ml in 24 hours) and the blood serum (maximum 1280 U/0.2 ml in 8 hours). After respiratory administration of ridostin interferon was detected only in the site of the administration in the tissues of the upper respiratory tract and lungs of the mice.

[Design of stimulating agents of non-specific resistance system]

The paper briefly reviews a study on the design of drugs enhancing the body's nonspecific resistance to pathogenic agents. To examine the potential regulatory effects on cytokine function was a main trend. The interferon inductor ridostin, dsRNA of microbiological origin, cytokines, as well as the recombinant probiotic strain yielding interferon alpha-2 synthesis were used as a pharmacological agent. This was shown by using a wide range of experimental models wherein these preparations activated the components of the non-specific resistance system resulting in the host's increased capacity to eliminate invasive agents and transformed cells.

[Features of formation of antiviral resistance upon local application of the interferon inducer ridostin]

Antiviral potency of an ointment dosage form of interferon (IF) inducer ridostin has been demonstrated in guinea pigs with genital herpes. Early beginning of therapy led to a 72% decrease of the intensity of clinical signs with cure 12-13 days earlier than in the control. Application of ridostin ointment onto the skin of intact animals caused an increase of IF level in the blood and of the phagocytic activity of peritoneal exudation macrophages. Ridostin effect on the total-systems factors of nonspecific defense appears to be one mechanism in the formation of antiviral resistance upon external application of this IF inducer.

[Modulation of the antitumor effect of cyclophosphamide by the recombinant probiotic Subalin]

A new preparation "subalin" developed on the basis of a recombinant saprophyte strain of Bacillus subtilis 2135/105 producing human interferon alpha-2 has been tested for its ability of increasing the effectiveness of antitumor therapy. The study used Lewis lung carcinoma bearing mice C57B1/6 treated with injections of 60 mg/kg body cyclophosphamide, intraperitoneally, on days 3 and 7 of tumor growth. Subalin was administered per as on days 1-14 after tumor transplantation. Combined treatment with cyclophosphamide and subalin resulted in a significantly higher inhibition of primary tumor growth and metastatic spreading as compared with control receiving cyclophosphamide alone. Also, there were fewer animals with metastasis; the average number of these lesions per animal and the total affected area were less. Subalin proved to exert a moderate antitumor and antimetastatic effect. The cytostatic activity of peritoneal macrophages was higher in mice treated with subalin. It is suggested that the chemo-sensitizing and antitumor effects of subalin are due to its ability to induce endogenous interferon production.

[Toxic properties of recombinant tumor necrosis factor]

Toxic properties of recombinant human tumor necrosis factor (TNF-beta) were studied on noninbred albino mice. In the maximum tolerable doses the preparation induced a decrease in the body weight and temperature of the animals as well as development of glyco- and leukopenic reactions and damage of the internal organ structures. The preparation effects were observed early after the exposure and were mainly reversible. The most TNF-beta sensitive organs were the liver, lungs, adrenal gland, thymus and spleen. The major link in the pathological process development under the effect of the TNF-beta toxic doses was likely increased intravascular blood coagulability evident from a marked procoagulant activity of the preparation.

[Ability of a recombinant protein containing fragment 114-122 of myelin basic protein, to cause allergic encephalomyelitis in guinea pigs]

Four genetic constructions have been designed, capable of producing in E. coli the hybrid beta-galactosidases containing the encephalitogenic determinant 114-122 of myelin basic protein. The ability of chromatography-purified proteins to cause allergic encephalomyelitis in guinea pigs has been investigated. Only one out of four proteins carrying at least one complete replica of encephalitogenic determinant did induce allergic encephalomyelitis in animals. Effects of the structural context of the encephalitogenic determinant on its functional activity are discussed.

[Pharmacological analysis of the effect of natural double-helical nucleic acids on the detoxifying function of the liver]

The effect of interferon inductors i.e. double stranded RNAs from S. cerevisiae and phage F6 on the liver detoxicating function was studied on noninbred albino mice. The liver detoxicating function was tested by duration of hexenal sleep. It was shown that intraperitoneal administration of the yeast and phage RNAs in doses of 1/5 LD50 for three times led to increasing of the narcotic sleep duration in the animals by 65 and 207 per cent, respectively. The effect was of the dose-dependent nature. The doses not inducing reliable inhibition of hexenal metabolism were equal to 1/10 LD50 for the yeast dsRNA and 1/27 LD50 for the phage dsRNA. The inhibitory effect of the dsRNAs was retained for 2-3 days after discontinuation of the drug use. When the dsRNAs were administered simultaneously with nembutal, an inductor of the liver microsomal enzymes, the dsRNAs eliminated its inducing effect. Simultaneous administration of alpha-tocopherol lowered the dsRNA effect on hexenal metabolism. The findings suggested that the dsRNA inhibitory effect on the liver detoxicating function was grounded on the mechanisms associated with inhibition of syntheses and activation of lipid peroxidation specific of the monooxygenase system under the action of the dsRNAs.

[Acute toxicity and cumulative properties of poly(I).poly(C) and poly(G).poly(C) polyribonucleotide complexes]

Acute experiments on mice and rats were made to determine the intraperitoneal lethal doses of the polyribonucleotide complexes poly (I).poly (C) and poly (G).poly (C) manufactured in this country. Changes in the function of cardiovascular, nervous, thermoregulatory and motor systems seen after injection of both complexes were shown to have some features in common but to differ in the rate and severity of poisoning. It was disclosed that the test polyribonucleotide complexes might be attributed to a group of substances that manifest the medium degree of cumulation.

[Conditioned reflex reproduction of evoked potentials during reinforcement by electrostimulation of the hypothalamus]

Conditioned evoked potentials to stimulation of a limb, a light flash or a short tone were studied on rats in acute experiments with nembutal anaesthesia and in chronic experiments. Electrical stimulation of the hypothalamus was used as reinforcement. Following the pairings of conditioned and hypothalamic stimulation, the appearance of conditioned EP was recorded, as manifest in the period of the previously applied unconditioned signal after its omission. Their emergence was facilitated after high-frequency stimulation of the hypothalamus or administration of galantamine, an anticholinesteraze drug. Coagulation of the hypothalamus did not prevent any manifestation of conditioned evoked potentials.