Introduction. Infection of canids with canine parvovirus (CPV), especially in puppies, leads to serious damage to the gastrointestinal tract in a short period of time, up to a fatal outcome. In this regard, early and rapid diagnosis is crucial for initiating therapy and preventing the spread of infection. In this connection, immunochromatographic analysis (ICA) is the preferred method because it allows rapid detection of virus infection. In addition, this method is highly specific and does not require complex laboratory equipment, which greatly simplifies its use in comparison with other common methods for detecting canine parvovirus. The aim of this study is the development of an ICA test system for the detection of the VP2 protein of canine parvovirus. Materials and methods. Monoclonal antibodies to the recombinant VP2 protein of canine parvovirus were obtained using hybridomic technology. Colloidal gold is synthesized by the citrate method. Results. Monoclonal antibodies (MABs) against the VP2 protein of canine parvovirus were obtained and characterized, colloidal gold (AuNPs) was synthesized, the conditions for conjugation of MABs with AuNPs were selected, and the optimal ratios of the components of the test system were determined. The visual limit detection (vLOD) was 1.56 ng/mL. The developed ICA test system has shown high diagnostic efficiency in model experiments with a known concentration of VP2, as well as in sick animals with a confirmed diagnosis. Conclusion. An ICA test system has been developed to determine the VP2 protein of canine parvovirus. The resulting test system can be used as a fast and effective diagnostic tool for detecting CVP in the canine clinical specimens.
The aim of the review was to analyze current literature data on the mechanisms by which the influenza A virus causes a decrease in the level of the SLC7A11 (xCT) protein in human cells, which contributes to the initiation of ferroptosis. The literature search was performed in the eLIBRARY.RU, CyberLeninka, Google Scholar, PubMed databases for the period 2009-2026. Data are presented on the role of the Xc⁻ transport antioxidant system and its key subunit SLC7A11 in the pathogenesis of influenza infection in the context of ferroptosis induction. The Xc− system mediates the import of cystine, which is essential for the synthesis of glutathione, the primary intracellular antioxidant. The molecular mechanisms of ferroptotic cell death are described, including Xc− dysfunction, activation of the transferrin receptor TfR1, lipoxygenase ALOX15. Data on experimental evidence of ferroptosis induction upon influenza virus infection, obtained using A549, 16HBE, BeWo cell lines as well in mouse cells, are presented. This evidence includes increased expression of TRIM family proteins, TNF-α, and elevated TGF-β1 mRNA levels. Hypothetical models of indirect pathogen-mediated effects are discussed, suggesting SLC7A11 suppression driven by pro-inflammatory cytokines (TNF, IFN-γ, IL-1β, TGF-β1) and proteins p53 and BAP1. The need for further research to confirm the contribution of the pathways discussed and to assess their clinical potential as targets for therapy or biomarkers is emphasized.
Background. Bats are a natural reservoir for various viruses, including SARS-CoV-2. Bat cell cultures are used to study the cellular tropism of zoonotic viruses, which helps determine the range of hosts and their possible origin. The aim of the study is to assess the sensitivity of the bat kidney cell primary culture of Murina hilgendorfi to infection by different genetic variants of SARS-CoV-2. Materials and methods. To study the tropism of coronaviruses, a primary culture of M. hilgendorfi bat kidney cells was prepared and infected with strains of different SARS-CoV-2 genetic variants from the Collection of Pathogenic Microorganisms of the G.P. Somov Research Institute of Epidemiology and Microbiology of Rospotrebnadzor (Wuhan, Delta, and Omicron). Vero-E6 cells were used as a positive control. The effectiveness of viral replication was assessed in dynamics by cytopathogenic effect (CPE) and RT-qPCR in the supernatants of cell cultures, with determination of the threshold cycle (Ct). Results and discussion. On the 7th day cultivation of the primary culture of the bat kidney cells, a heterogeneous monolayer of cells with 70–80% confluency was formed. The monolayer was represented by fibroblast-like and epithelial-like cells. After infecting a culture of bat kidney cells with different SARS-CoV-2 genetic variants, the virus’s CPE was already evident at the initial time points and increased over the period of observation. SARS-CoV-2 RNA was detected in the supernatant of bat kidney cell lysate on the 2nd day after infection, by the 6th day, the Ct values in RT-qPCR decreased for all three genetic variants. This indicates that coronaviruses replicate in bat kidney cells. The reproduction of coronaviruses in the kidney cells of M. hilgendorfi indicates the possibility of virus carriage by representatives of this species, as well as their potential participation in the epidemic process as carriers of viruses. This, in turn, allows us to talk about the role of bats in the formation of natural reservoirs of coronavirus infection. Conclusions. The primary culture of kidney cells of M. hilgendorfi was obtained for the first time. This culture is susceptible to strains of different SARS-CoV-2 genetic variants (Wuhan, Delta, and Omicron), as confirmed by CPE and RT-qPCR. According to the results of the RT-qPCR analysis, no differences in sensitivity were observed between the three genetic variants.
INTRODUCTION:Rotaviruses exhibit a high degree of variability, which is ensured by the process of reassortment and antigenic drift. This leads to significant genetic diversity, including the emergence of strains with rare and unusual genotypes. This study, for the first time, provides a molecular genetic characterization of a rare RVA strain with the genotype G2P[9] based on all genome segments. AIM OF THE STUDY:To conduct a molecular genetic characterization of a rare strain of RVA genotype G2P[9] based on all genome segments, as well as to compare the strain with previously characterized representatives of subgroup BA222 from Nizhny Novgorod. MATERIALS AND METHODS:Rotavirus-positive stool samples from children were analyzed using PCR-genotyping and PAGE. For the isolate under study, cDNA fragments of each of the 11 genes (VP1-VP4, VP6, VP7, NSP1-NSP5) were sequenced. Nucleotide and amino acid sequence analysis and phylogenetic tree construction were performed using MEGA X. RESULTS:In the period 2022-2023, a single strain of the unique genotype G2P[9] was identified in Nizhny Novgorod, characterized by a "broad" RNA electrophoretype (G2-P[9]-I2-R2-C2-M2-A3-N2-T3-E3-H3). The study showed that the origin of this strain is associated with reassortment processes between Nizhny Novgorod Wa- and BA222-like RVA, as well as isolates of the G3P[9] genotype from China. The studied strain, along with rotaviruses from China, differed from the Nizhny Novgorod BA222-like strains by the presence of 43 nucleotide substitutions in nine genes. These differences resulted in ten amino acid substitutions, eight of which were radical. All radical substitutions were located in the functionally active regions of the VP1, VP3, and VP4 proteins, which play a key role in the replicative cycle of rotaviruses. DISCUSSION:We characterized a strain with the rare G2P[9] genotype based on its complete genotype for the first time in Russia and globally. These results expand our understanding of the diversity of reassortant rotaviruses and complement our knowledge of the genotypic structure of the rotavirus population in Nizhny Novgorod. CONCLUSION:The wide genetic diversity of rotaviruses, maintained by reassortment and antigenic drift, may facilitate rotaviruses' ability to overcome immunological pressure. Therefore, continuous molecular monitoring of circulating rotavirus variants is necessary to monitor the emergence of new variants and assess changes in rotavirus virulence following reassortment processes.
The global rise in antimicrobial resistance (AMR) poses an urgent threat to public health, and novel alternatives to traditional antibiotics are needed. One of the most promising options is bacteriophages, viruses that infect and destroy bacteria. Once overshadowed by the discovery of antibiotics, phage therapy is now regaining attention, driven by advances in genomics, synthetic biology, and targeted medicine. This review examines the biology, diversity, and therapeutic use of bacteriophages in treating bacterial infections, especially those caused by multidrug-resistant pathogens. It also discusses how phages act through natural mechanisms, such as lytic enzymes (holins, endolysins, and muralysins), and highlights new genetic engineering techniques, such as CRISPR-Cas systems, phage recombineering, and synthetic genome reboots. In addition to clinical applications, we evaluate phages as biocontrol agents for food safety, environmental sanitation, and biofilm management. Additionally, the article explores key issues in phage therapy, including regulatory frameworks, formulation stability, dynamics of phage-host resistance, and the importance of rapid diagnosis. When properly integrated into modern health and biotechnology practices, bacteriophages offer significant potential and a sustainable solution to the global challenge of antimicrobial resistance.
