Introduction. Campylobacteriosis is among the leading causes of acute gastrointestinal infections. The severity of campylobacteriosis and the development of long-term complications may be influenced by the genotype of the pathogen, whose biological properties can affect immune response parameters. The aim of the study was to identify common genotypes of epidemic clones of Campylobacter pathogens and to investigate characteristics of the immune response and severity of the disease. Materials and methods. The study included 203 patients aged from 1 month to 17 years with campylobacteriosis who underwent treatment at the clinic of the Federal State Budgetary Institution "DNKCIB FMBA" in 2019–2021. The diagnosis was confirmed using polymerase chain reaction method. Patient samples were also analyzed using culture-based methods. Total DNA was extracted using the QIAamp DNA Mini Kit. Genetic determinants encoding virulence factors and MLST typing were performed using the ResFinder program. The immune status of patients was assessed on days 1 and 7 of the illness. Immunological investigation included measurement of serum immunoglobulin concentrations (IgA, IgM, IgG), C-reactive protein, and cytokines (IL-1β, IL-1, IL-2, IL-4, IL-5, IL-6, IL- 7, IL-8, IL-10, TNF-α, and IFN-γ). Results. When analyzing the frequency of detection of Campylobacter sequence types in children with clinical intestinal infections, it was found that the profile of isolated isolates is most similar to those from countries of North America (USA and Canada), Northern Europe (Great Britain, Holland ) and Scandinavia (Denmark, Sweden, Finland). Identification of a pathogen with the flgE+, cdtA+, cdtC+ genotype was accompanied by a statistically significant increase in the level of IL-8 and a decrease in the content of IgA in the peripheral blood serum, which reflected the low efficiency of the immune response during infection with Campylobacter and predetermined the severe course of the infectious process during the disease.

Trace amine-associated receptors (TAAR1-TAAR9) are a family of G-protein-coupled monoaminergic receptors which might have great pharmacological potential. It has now been well established that TAAR1 plays an important role in the central nervous system. Interestingly, deletion of TAAR9 in rats leads to alterations in the periphery. Previously, we found that knockout of TAAR9 in rats (TAAR9-KO rats) decreased low-density lipoprotein cholesterol levels in the blood. TAAR9 was also identified in intestinal tissues, and it is known that it responds to polyamines. To elucidate the role of TAAR9 in the intestinal epithelium, we analyzed TAAR9-co-expressed gene clusters in public data for cecum samples. As identified by gene ontology enrichment analysis, in the intestine, TAAR9 is co-expressed with genes involved in intestinal mucosa homeostasis and function, including cell organization, differentiation, and death. Additionally, TAAR9 was co-expressed with genes implicated in dopamine signaling, which may suggest a role for this receptor in the regulation of peripheral dopaminergic transmission. To further investigate how TAAR9 might be involved in colonic mucosal homeostasis, we analyzed the fecal microbiome composition in TAAR9-KO rats and their wild-type littermates. We identified a significant difference in the number of observed taxa between the microbiome of TAAR9-KO and wild-type rats. In TAAR9-KO rats, the gut microbial community became more variable compared with the wild-type rats. Furthermore, it was found that the family Saccharimonadaceae, which is one of the top 10 most abundant families in TAAR9-KO rat feces, is almost completely absent in wild-type animal fecal samples. Taken together, these data indicate a role of TAAR9 in intestinal function.

В статье приведены результаты обследования 20 пациентов с желчнокаменной болезнью, которым во время плановой лапароскопической холецистэктомии проводили забор желчи и участка стенки желчного пузыря для исследования микробиоценоза. Микробиоценоз исследовали культуральным методом и методом полимеразной цепной реакции в реальном времени. В таксономической структуре выявленных из желчного пузыря бактерий преобладали Bifidobacterium spp. , Bacteroides spp. , Lactobacillus spp. , E. coli. Большинство выделенных бактерий Enterococcus spp. обладали генами, кодирующими различные факторы патогенности.

At present, the role of intestinal microbiota in diverse diseases of the central nervous system, including of multiple sclerosis (MS) has been extensively investigated. Self-reactive CD4+ Th1 and Th17 cells specific to myelin-derived antigens play a key role in the MS pathogenesis. Taking into consideration pathogenetic features related to MS development, we examined a relation between intestinal microbiocenosis and abundance of various peripheral blood helper T (Th) cell subsets in MS patients. Objective of the study: to assess prevalence of individual members of the intestinal microbiota in MS patients and analyze a relation with peripheral blood Th cell subsets. Prevalence of symbiotic and opportunistic microbial species was estimated by bacteriological method and real time PCR in 112 MS patients (72 females, 40 males) of varying severity and duration. Th cell subsets (Th1, Th2, Th17, Th1/Th17, Th17/Th22, DP Th17) were analyzed by using multi-color flow cytometry based on Th cell subset-specific surface expression of chemokine receptors. A relationship between individual intestinal microbiota species and severity, duration and rate of MS progression, as well as with the phenotype of immune cells was assessed. It was found that the most significant correlation between percentage of peripheral blood Th cell subsets was observed with prevalence of Lactobacillus spp., Enterococcus spp. and Enterobacter spp. Moreover, prevalence of Enterococcus spp. Th cell composition influenced synergistically or antagonistically together with Enterobacter spp. or Lactobacillus spp., respectively. It is suggested that direct and indirect impact of intestinal microbiota composition on human immune system might contribute to developing novel strategies for treating MS.

Metabolic syndrome (MS) is associated with the current diseases: obesity and diabetes, which are accompanied by changes of intestinal microbiota and of immune and neurohumoral systems. The aim of the work was to analyze the data obtained in the study of the role of the intestinal microbiota in case of MS and its correction. Discussed issues: features of the microbiota in MS metabolic endotoxemia and bacteremia, the role of surface structures and metabolites of bacteria, the ability to diagnostics and treatment of MS using microbiological approaches.