Combined Drug with Antibacterial Effect Supports the Normal Intestinal Microflora.

Widespread use of antibiotics leads to an imbalance of normal intestinal microflora and to the development of multidrug resistance. The problem can be solved by administration of the antibiotics in combination with the drugs that have an immunotropic effect. We studied the effect of the drug containing technologically processed affinity purified antibodies to IFNγ, CD4 receptor, ß2-microglobulin of MHC class I, and ß2-domain of MHC II combined with antibiotics on the composition of intestinal microflora of pigs and the total number of microbiome resistance genes. Using the methods of NGS sequencing and quantitative PCR, we found that the drug contributes to the maintenance of normal microflora and, consequently, to the symbiotic relationship of the host with microflora, and prevents the reproduction of pathogenic bacterial species. Analysis for the presence of the resistance genes of gastrointestinal microorganisms showed that the drug does not affect the qualitative and quantitative composition of these genes of the intestinal microbiome.

[Susceptibility of animal species to experimental SARS-CoV-2 (Coronaviridae: Coronavirinae: Betacoronavirus; Sarbecovirus) infection].

Due to the new coronavirus infection pandemic, the global scientific community has been forced to change the direction of the most research, focusing on vaccine development as well as the search for new antiviral drugs to treat COVID-19. The choice of experimental models, timeframe and approaches for evaluating drugs and vaccines under development is crucial for the development of effective measures to prevent and control this disease.The purpose of this review was to summarize the relevant data concerning the susceptibility of laboratory animals to SARS-CoV-2. This paper describes the most virus-susceptible animal species that can be used to reproduce coronavirus infection, stressing the main advantages and disadvantages of each of them.According to the latest data, small rodents (Rodentia) and non-human primates (Strepsirrhini) are commonly used in the scientific community to model coronavirus infection. The viral load in the upper and lower parts of the respiratory system, clinical symptoms of infection (weight loss, body temperature and general health status), pathomorphological picture in target organs and the production of antibodies after infection are considered to the main markers of pathology. Despite the vast amount of data, none of the described models of SARS-CoV-2 infection may be considered a gold standard, since they do not reproduce all spectrum of morphological and pathogenetic mechanisms of infection, and do not fully reflect the clinical picture observed in patients in human population.Based on the analyzed literature data, we suppose that Syrian hamster (Mesocricetus auratus) and mice (Muridae) expressing the angiotensin converting enzyme receptor 2 (ACE2) are the most suitable animal species for their use in experiments with SARS-CoV-2 infection. The development of neutralizing antibodies makes it possible to evaluate the efficacy of vaccines, while the course and severity of symptoms infection makes the use of mice and hamsters especially popular for screening pharmacological substances with antiviral mechanism of action, when their administration can prevent or slow the disease progression.

IVIG ameliorate inflammation in collagen-induced arthritis: projection for IVIG therapy in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a systemic inflammatory autoimmune disease that leads to joint destruction and disability. Despite a significant progress in administration of biological agents for RA patients, there is still a need for improved therapy. Intravenous immunoglobulins (IVIG), a pooled polyspecific immunoglobulin (Ig)G extracted from 5000 to 20 000 healthy subjects, showed beneficial therapeutic effect in patients with immune deficiency, sepsis and autoimmune diseases. The current study aimed to investigate the beneficial effect of treatment with IVIG in established collagen-induced arthritis in DBA/1j mice. Murine arthritis was induced in DBA/1j mice. Treatment with IVIG began when the disease was established. The clinical score was followed twice a week until day 48. The mice were bled for plasma and the paws were hematoxylin and eosin (H&E)-stained. Cytokine profile in the plasma was analyzed by Luminex technology and titers of circulating anti-collagen antibodies in the plasma was tested by enzyme-linked immunosorbent assay. Our results show that treatment with IVIG in murine significantly reduced the clinical arthritis score (P < 0·001). Moreover, mode of action showed that IVIG significantly reduced circulating levels of inflammatory cytokines [interferon (IFN)-γ, interleukin (IL)-1ß, IL-17, IL-6, tumor necrosis factor (TNF)-α, P < 0·001], inhibiting anti-collagen antibodies (P < 0·001) in the plasma of collagen-induced arthritis mice. Importantly, histopathological examination revealed that IVIG treatment prevented the migration of inflammatory immune cells into the cartilage and synovium, reduced the extent of joint damage and preserved joint architecture. Our results proved for the first time the valuable anti-inflammatory treatment of IVIG in experimental RA. We propose IVIG therapy for a subgroup of patients with rheumatologically related diseases.

[Release-active antibodies to S100 protein are able to improve the experimental allergic encephalomyelitis].

AIM: To reveal the effects of release-active antibodies to S100 protein in an animal model of multiple sclerosis. MATERIAL AND METHODS: Sixty female Wistar rats, aged 12 weeks, were included in the study. The pathology was induced by subcutaneous injection of the spinal cord homogenate. Afterwards the rats received a water solution of release-active antibodies to S100 protein (2,5 ml/kg/day, tenoten) or distilled water intragastrically during 30 days. Intramuscular injections of glatiramer acetate (4 mg/kg/day, copaxone) were used as a positive control. RESULTS AND CONCLUSION: Release-active antibodies to S100 protein enhanced the latency period of the disease, reduced its peak intensity and compensated the loss of body weight of the animals. The experimental drug effect was similar to the results of copaxone injections.