In Vitro Antiviral Activity of a New Indol-3-carboxylic Acid Derivative Against SARS-CoV-2.

The coronavirus disease (COVID-19) pandemic has brought into sharp relief the threat posed by coronaviruses and laid the foundation for a fundamental analysis of this viral family, as well as a search for effective anti-COVID drugs. Work is underway to update existent vaccines against COVID-19, and screening for low-molecular-weight anti-COVID drug candidates for outpatient medicine continues. The opportunities and ways to accelerate the development of antiviral drugs against other pathogens are being discussed in the context of preparing for the next pandemic. In 2012-2015, Tsyshkova et al. synthesized a group of water-soluble low-molecular-weight compounds exhibiting an antiviral activity, whose chemical structure was similar to that of arbidol. Among those, there were a number of water-soluble compounds based on 5-methoxyindole-3-carboxylic acid aminoalkyl esters. Only one member of this rather extensive group of compounds, dihydrochloride of 6-bromo-5-methoxy-1-methyl-2-(1-piperidinomethyl)-3-(2-diethylaminoethoxy) carbonylindole, exhibited a reliable antiviral effect against SARS-CoV-2 in vitro. At a concentration of 52.0 µM, this compound completely inhibited the replication of the SARS-CoV-2 virus with an infectious activity of 106 TCID50/mL. The concentration curves of the analyzed compound indicate the specificity of its action. Interferon-inducing activity, as well as suppression of syncytium formation induced by the spike protein (S-glycoprotein) of SARS-CoV-2 by 89%, were also revealed. In view of its synthetic accessibility - high activity (IC50 = 1.06 µg/mL) and high selectivity index (SI = 78.6) - this compound appears to meets the requirements for the development of antiviral drugs for COVID-19 prevention and treatment.

[The problem of the use of interferons in the novel coronavirus disease COVID-19 (Coronaviridae: Coronavirinae: Betacoronavirus: Sarbecovirus)].

By the end of 2021, about 200 studies on the effect of interferons (IFNs) on the incidence and course of the new coronavirus infection COVID-19 (Coronaviridae: Coronavirinae: Betacoronavirus: Sarbecovirus) have been reported worldwide, with the number of such studies steadily increasing. This review discusses the main issues of the use of IFN drugs in this disease. The literature search was carried out in the PubMed, Scopus, Cochrane Library, Web of Science, RSCI databases, as well as in the Google Scholar preprint database using the available search queries «MeSH for coronavirus¼, «SARS-CoV-2¼, «IFN drugs¼, and «COVID-19¼. Interferon therapy is indicated for early administration (within the first 5 days of patient admission) in cases of mild to moderate COVID-19 to take advantage of the narrow therapeutic window of IFNs action. Control and suppression of viral replication requires therapy with IFNs and other effective antiviral agents that inhibit the reproduction of SARS-CoV-2 and induce several interferon-stimulated genes (ISG). Type I IFNs (IFN-I) exhibit potent pro-inflammatory properties and activate a wide variety of different cell types that respond to IFNs stimulation and pathogen entry. IFN-III confer local mucosal antiviral immunity without inducing the strong systemic pro-inflammatory responses associated with IFN-I. The use of IFNs drugs in the therapy of new coronavirus infection requires a cautious and differentiated approach, because in severe cases they can aggravate viral pathogenesis by causing excessive intensity of inflammatory reactions. The unique biological properties of substances of this class allow us to consider them as therapeutic agents with significant potential for use in patients with COVID-19.

[Interferon gamma in the treatment of patients with moderate COVID-19].

INTRODUCTION: Interferons are produced in response to the presence of pathogens in cells and are responsible for the proper formation of immune reaction. Preliminary data obtained in studies of properties of recombinant interferon gamma (IFN-γ) that involved patients with community-acquired pneumonia (including bacterial), acute respiratory viral infection (ARVI), influenza and new coronavirus infection have shown promising results.The purpose of the study was to assess the effect of subcutaneous administration of IFN-γ in patients with viral pneumonia on the changes of vital signs and the duration of hospital stay. MATERIAL AND METHODS: An open-label, randomized, low-interventional study included patients with moderate new coronavirus infection COVID-19 over 18 years of age of both sexes. IFN-γ 500,000 IU was administered s/c, daily, once a day, during 5 days. RESULTS: IFN-y in addition to complex therapy of the disease resulted in more favorable changes in the stabilization of vital signs, as well as in reduced length of fever and hospital stay by 2 days what allows suggesting a positive effect of this substance on the recovery processes in patients with moderate COVID-19. Special emphasis should be made to the fact that patients who received recombinant IFN- γ experienced no progression of respiratory failure and required no transfer to intensive care unit. DISCUSSION: This study confirms earlier obtained data on the positive effect of IFN-y on the rate of clinical stabilization and recovery of patients with community-acquired pneumonia and viral infections. Presented results are limited to a small number of patients; further study of drug properties in post-marketing studies is required. CONCLUSION: Progress in the treatment of patients with moderate COVID-19 by adding recombinant IFN-γ to the complex therapy may reasonably expand the range of existing treatment options for this infection.

[Interferon-regulating activity of the CelAgrip drug and its influence on the formation of reactive oxygen species and expression of innate immunity genes in Burkitt's lymphome cells cultures.]

INTRODUCTION: Interferons (IFN) and IFN inducers are effective in suppressing viral reproduction and correcting of the innate immunity mechanisms. The aim of the study was to test the hypothesis of the possible involvement of the IFN inducer CelAgrip (CA) as an activator or suppressor of antiviral effects in Burkitt's lymphoma (LB) cell cultures with different ability to produce Epstein-Barr virus antigens (EBV). MATERIAL AND METHODS: The kinetic analysis of the dynamics of reactive oxygen species (ROS) production and determination of gene group expression by real-time PCR in response to CA treatment were done in human cell lines LB P3HR-1 and Namalva, spontaneously producing and not producing EBV antigens. RESULTS AND DISCUSSION: When treating CA in Namalva cells, a decrease in the ROS activation index was found; in P3HR-1 cells, an increase was observed. After treatment with CA, there was no reliable activation of the IFN-α, IFN-ß and IFN-λ genes in Namalva cells, but the expression of the ISG15 and P53(TP53) genes was increased more than 1200 times and 4.5 times, respectively. When processing the CA of P3HR-1 cells, the expression of IFN-α genes increased by more than 200 times, IFN-λ - 100 times, and the ISG15 gene - 2.2 times. The relationship between IFN-inducing action of CA and the activity of ISG15 and ROS in LB cell cultures producing and not producing EBV antigens is supposed. CONCLUSION: In Namalva cells that do not produce EBV antigens the treatment of CA results in suppression of ROS generation and activation of the expression of genes ISG15 and P53 (TP53); in P3HR-1 cells producing EBV antigens, the opposite picture is observed - the formation of ROS and the expression of the IFN-α and IFN-λ genes are activated and the activity of the ISG15 and P53 (TP53) genes is suppressed.

[Interferon-regulating activity of the celagrip antiviral drug and its influence on formation of reactive oxygen species and expression of innate immunity genes in the follicular lymphoma patients].

INTRODUCTION: Medicines from the group of interferon inducers (IFNs) "swith on" the synthesis of type 1 interferons (IFN-I) and induce the expression of IFN-stimulated genes (ISGs) that regulate innate immunity reactions and protect the host from infectious agents and the tumour pathology.The purpose of the study was to determine the role of the drug celagrip (CA) in the activation of innate immunity genes and the effect on the production of reactive oxygen species (ROS) in patients with follicular lymphoma (FL). OBJECTIVES:  to study the intensity of ROS production and the level of expression of the IFN-α2, IFN-λ1, ISG15, BCL2, P53(TP53) and USP18 genes in response to the treatment of blood cells of patients with FL with the preparation of CA. MATERIAL AND METHODS: The study involved primary cancer patients diagnosed with follicular lymphoma (FL) and healthy volunteers. A kinetic analysis of the dynamics of production of reactive oxygen species (ROS) was performed in whose blood cells, and the expression of the group of genes was determined by real-time PCR in response to CA processing. RESULTS AND DISCUSSION: ROS production by blood cells of patients with FL and volunteers in the presence of CA significantly decreased (P < 0.05). The level of gene expression of ISG15, P53(TR53) and USP 18 in the group of patients with FL was significantly higher than that in the group of volunteers. When treating blood cells with CA, it becomes possible to divide patients with FL into groups with a positive and negative response in accordance with the level of expression of the USP18 gene. We divided FL patients into groups with a positive and negative response in accordance with the level of USP18 gene expression after treatment of blood cells with CA. CONCLUSIONS: The CA drug reduces the production of ROS and simultaneously stimulates the activity of the innate immunity genes ISG15, P53(TP53) and USP18 in the blood cells of patients with FL.

[Cytokine-regulating activity of anti-virus preparation CelAgripus in Burkitt's lymphoma stable B-cell lines.]

INTRODUCTION: Cytokines activated in response to immunosuppressive viral infections can directly or indirectly affect the neoplastic transformation of B cells. In this study, we studied a new substance designed to produce the antiviral drug CelAgrip (CA, CelAgripus), which exhibits interferon (IFN) and cytokine-inducing activity and, apparently, can be used as an activator of antiviral immunity. Purpose - is to evaluate the cytokine-regulating effect of CA in Burkitt's lymphoma (LB) cell lines latently infected with the Epstein-Barr virus (EBV). OBJECTIVES: to study the CA-induced expression of the cytokine genes IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-17, IL-18, IFN-α, IFN -γ, IFN-ß, IFN-λ1, IFN-λ2, IFN-λ3, TNF-α in normal and EBV transformed LB cells. MATERIAL AND METHODS: Cell line: the human embryo fibroblasts (HEF), Namalva, Daudi, Raji, P3HR-1. Preparations: CA, gossypol-acetic acid (GAA), sodium carboxymethyl cellulose (Na-CMC). METHODS: RT-PCR and methods for assessing cytotoxicity (MTT and Scepter 2.0 Merck cell counter). RESULTS: The effect of the CA preparation on the expression of IFN-λ, IL-1ß, IL-6, IL-8 and IL-10 genes was revealed. DISCUSSION: We observed the activation of gene expression of IFN-λ, IL-1ß, IL-6, IL-8 and suppression of IL-10 gene activity when treatment CA of LB cells. CONCLUSION: The substance CA has new effects on the activation of the expression of a number of key cytokine genes in stable Burkitt lymphoma cell lines.

[Ophthalmic drug films in the therapy of experimental herpetic keratoconjunctivitis.]

INTRODUCTION: The complexity of the treatment of herpetic keratoconjunctivitis is due to the severity of the disease, complications, the transition to chronic relapsing forms and the insufficient effectiveness of the drugs used, which leads to a steady increase in the number of patients. The aim of the study was to evaluate the therapeutic efficacy of the eye drug films «GlazAvir¼ in the experimental model of acute herpetic eye infection in rabbits. RESEARCH OBJECTIVES: to study the specific activity of «GlazAvir¼ and compare the long-term indicators of the level of manifestation of individual clinical signs of keratoconjunctivitis. MATERIAL AND METHODS: In the work we used rabbits of the Chinchilla breed, the herpes simplex virus type 1 and the eye drug films «GlazAvir¼. A model of ophthalmic herpetic infection was formed by infection of rabbits with virus-containing material of a pre-scarified eye cornea against the background of local anesthesia. Аnimals were treated with the drug «GlazAvir¼ - 1 application per day for 7 days. Animals were observed daily for 15 days, then every 3 days until the 25th day of observation. The effectiveness of the drug was evaluated at the peak of the development of the pathological process. RESULTS AND DISCUSSION: There was a decrease in mortality from 50 to 20%, and an increase in average life expectancy by 27.87%, compared with the control in animals treated with «GlazAvir¼. It was noted after activation of herpetic keratoconjunctivitis on the 2nd - 5th day, at the peak of the disease (6-9th day) a statistically significant decrease in the activity of the pathological process (p<0.05) by rabbits treated with the «GlazAvir¼ ophthalmic drug films. The tendency to normalization by the rabbits treated with the «GlazAvir¼ preparation was observed until the 14th day. CONCLUSION: The data obtained indicate the pronounced effectiveness of the «GlazAvir¼ preparation in the treatment of experimental herpesvirus keratoconjunctivitis.

THEORETICAL AND APPLIED ASPECTS OF THE INTERFERON SYSTEM: TO THE 60TH ANNIVERSARY OF THE DISCOVERY OF INTERFERONS.

The review contains a brief analysis of the 60-year history of the discovery, study and medical application of interferons, a new group of remarkable proteins that have found wide medical application in the therapy of virological, oncological, neurological, ophthalmic and other pathologies. Modern data on the classification of interferons and the mechanisms of their action are given. Particular attention is paid to the clinical use of medications of interferon and its inducers.

[AVIAN RECOMBINANT VIRUS H5N1 INFLUENZA (A/VIETNAM/1203/04) AND ITS ESCAPE-MUTANT m13(13) INDUCE EARLY SIGNALING REACTIONS OF THE IMMUNITY IN HUMAN LYMPHOCYTES].

The innate immune receptors TLR4, TLR7, TLR8, and RIG1 recognized the structures of the influenza viruses in human lymphocytes and were activated by the recombinant avian influenza virus A/Vietnam/1203/04 and its escape-mutant m13(13) during early period of interaction. The stimulated levels are not connected with viral reproduction. Donor cells with the low constitutive immune receptors gene expression levels showed higher stimulation. Inflammation virus effects resulted in. increasing production of TNF-alpha and IFN-gamma by lymphocytes. Signaling gene reactions of the parent and mutant viruses endosomal as well as cytoplasmic receptors are very similar. The mutant virus A/Vietnam/1203/04 (HA S145F), stimulated an increase in the transcription level of the membrane receptor gene TLR4 and a decrease in the level of activation of TNF-alpha gene. Further studies of natural influenza virus isolates are necessary to estimate the role of HA antigenic changes on immune reactions in humans.

[THERAPEUTIC POTENTIAL OF ALPHA-INTERFERON PREPARATIONS DUR- ING SOCIALLY-SIGNIFICANT HUMAN DISEASES OF VIRAL ETIOLOGY].

Interferons (IFN) belong to key cytokines of innate and adaptive immune response and play an important role in anti-viral and anti-tumor protection. At the same time, they possess a pro- nounced immune-modulating, anti-proliferative and anti-fibrotic effect. A general comparative characteristic of human IFN type I (α/ß), IFN type II (γ) and IFN type III (λ) and nosological directionality of contemporary drugs created on their base is examined in the review. Epidemiologic parameters for main socially-significant human diseases of viral etiology are presented: influenza and other ARVIs, herpes infection, chronic viral hepatitis B, C and D. Main attention is given to analysis of effectiveness of therapeutic application of preparations based on IFNα during the in- dicated infections, a specter of main IFNα induced side effects is listed. Recent achievements on the path of creation of principally new drugs based on IFN, that have lower toxicity and higher clinical effectiveness, as well as perspectives of application of preparations based on recombinant IFN for therapy of potentially, dangerous diseases are examined.

[Efficacy of polyprenyl phosphates in the experimental genital herpes model].

An experimental model of the primary genital herpes (herpes simplex type 2, HSV-2) in the female guinea pigs was suggested to study the infectious process activity of polyprenyl phosphates (PPP) and PPP+acyclovir (AC) complex treatment. The morphofunctional features of the guinea pig ovaries were studied in the control and experimental groups (the latter were inoculated with PPP and/or AC as a primary infection treatment) at the stage of the recurrent genital herpes aggravation. It was shown that in the case of combined PPP +AC use significant changes in the disease symptoms were observed, as well as a decrease in the infectious process activity and duration, and positive remote effect on the ovarian morphophysiology.

[Usage of interferon inducers during viral infections].

Domestic researchers succeeded to create a group of original interferon inducers (II) with a high chemotherapeutic index and suitable for the prevention and treatment of viral infections and a number of other diseases. Clinical application of II concerns, first of all, a wide range of viral infections: influenza and other acute respiratory viral infections, herpes, hepatitis, encephalitis, rabies, slow and mixed infections, etc. The accumulated experience is generalized and the conclusion is made about the main advantages of II, which induce a balanced synthesis of endogenous interferon without antigenicity of its own. It is emphasized that a single injection of II "includes" synthesis of IFN in certain populations of cells and organs and provides a relatively long circulation of IFN at a therapeutic level and creation of long-term anti-virus resistance. It is concluded that, in general, interferon inducers with pronounced antiviral and immunomodulatory properties are currently used as effective tools for the prevention and treatment of a variety of diseases. The fact that II different in their chemical nature act at different stages of reproduction of viruses and affect various links of the innate and adaptive immunity explains the increased scope of the application of this group of drugs in medical practice.

[[Antiviral activity of the interferon beta 1a].

The antiviral activity of the interferon beta Ia was studied using the example of the antiviral activity of the drugs interferon beta Ia Genfaxon and Rebif for the influenza and herpes. A pronounced antiviral effect of the drugs against influenza and herpes viruses was-shown far the first time.

[Mathematic prognosis of cagocel effectiveness for prophylaxis and therapy of influenza].

The possibility of using a mathematic model of influenza epidemic in evaluation of effectiveness of an etiotropic preparation cagocel for prophylaxis and therapy of influenza as well as determination of possible damage from influenza epidemics and outbreaks in major cities of Russia is shown.

[The therapeutic efficacy of cycloferon and the pharmacological activity of interferon inducers].

The review describes endogenous interferon inductors that belong to antiviral drugs and contain different chemical compounds. Among the groups identified by the authors, there are promising and most effective medicines inducing different types of interferon in the body, as well as their mechanism of action. The paper shows the synthesis of endogenous interferon and the level of its accumulation in the organs and tissues. The clinical effects of methylglucamine acridonacetate (cycloferon) are depicted in patients with major viral (influenza, acute respiratory viral and arboviral infections, and viral hepatitis) and bacterial (brucellosis, tuberculosis) infections, or endometrial hyperplastic processes. Cycloferon is shown to be used as an etiotropic and antipathogenic drug.

[Modern Russian Etiotropic Antiinfluenza Drugs].

Two main groups of the Russian etiotropic drugs recommended by the Ministry of Health of the Russian Federation for prophylaxis or treatment of influenza are described in the review, i.e. chemotherapeutics whose targets are various stages of the influenza virus reproduction and interferons and their inductors engaging innate immunity patterns.

Ridostin induces transcription of a wide spectrum of interferon genes in human cells.

The effects of Ridostin on the transcription of IFN family genes in human fibroblasts and lymphocytes were studied by quantitative real-time PCR. The degree of gene induction by Ridostin was most pronounced in fibroblasts, and was significantly higher than the induction by Kagocel: transcription of IFN-ß, oligoadenylate synthetase, and double-stranded RNA-dependent protein kinase genes increased by about 2000, 100, and 20 times, respectively. In lymphocytes, Ridostin also activated a wide variety of IFN family genes, including genes of IFN-ß, IFN-γ, and IFN-dependent enzymes, but this induction was less pronounced than in the fibroblasts. It was shown that gene response in lymphocyte from a child with cancer is reduced in comparison with that of adult healthy participant. Ridostin, and even more so Reaferon up-regulated activities of ß-actin, glycerophosphate dehydrogenase, and ß2-microglobulin genes, thus making impossible or limiting their use as constitutive stable reference genes (standards) in PCR-assays of IFN and their inductors.

[Results and prospects of interferone inducers using in infectious diseases treatment].

There is represented the current classification of interferon inducers of various chemical groups related to antiviral agents, described the mechanisms of synthesis of different types of endogenous interferon in blood serum. The effectiveness of methylglucamine acridonacetates in integrated treatment of chronic hepatitis C, tuberculosis with HIV infection background, chronic brucellosis, arboviral diseases, including West Nile fever, as well as influenza and acute respiratory infections are shown. For successful treatment of acute and chronic diseases with endogenous interferon inducers should be applied as early as possible, at an average level of viremia , to enhance the effect of drugs with the directed etiotropic action and immunomodulators, which achieves the optimal pharmacotherapeutic effect.

[Virus infections and interferon inducers in the complex therapy].

Interferon inductors of various chemical groups, belonging to antivirals, and induction of several types of endogenous interferon in blood serum are described. Cycloferon was shown efficient in the complex treatment of chronic hepatitis C, tuberculosis in HIV-infected subjects, arbovirus diseases, influenza and acute respiratory virus infections.

[Discovery and scientific investigation of a biological phenomenon].

A brief discussion is devoted to the 55-year long history of interferons and the contribution of domestic researchers to the study of this problem.