Differences in the amino acid composition of the antigen epitopes of the VP7 protein of Russian rotaviruses with the G9 genotype and the vaccine strains RotaTeq, Rotavac, and Rotarix

Introduction. Rotaviruses of group A (RVA) with genotype G9P[8] are a common cause of acute gastroenteritis in children in Russia. In Nizhny Novgorod, the part of G9P[8] among all RVA strains reached 63.1% during 2016–2017 epidemic season. Two live rotavirus vaccines, RotaTeq and Rotarix have been successfully introduced into the national immunization programs worldwide. In addition, the Indian vaccine Rotavac, based on the strain with G9P[8] genotype, is used on a regional level. The parent strains for all mentioned vaccines were isolated more than 30 years ago. There is no data about phylogenetic analysis and comparative analysis of antigenic epitopes of Russian G9P[8] wild-type isolates and vaccine strains. In the present study, for the first time, we provide a comparative phylogenetic analysis and research of the amino acid composition of the B- and T-cell epitopes of the VP7 protein between Russian rotaviruses with the G9 genotype and the vaccine strains in RotaTeq, Rotarix and Rotavac composition. Materials and methods. The nucleotide and amino acid sequences of the VP7 gene of RVA with genotype G9 were studied. The rotaviruses had been previously isolated from children hospitalized with acute gastroenteritis in the infectious hospital in Nizhny Novgorod during 2011–2016. Results. A phylogenetic analysis of the nucleotide sequences of the VP7 gene showed that the Nizhny Novgorod strains belong to the G9-III allele. Based on the amino acid sequences VP7, three B-cell epitopes (7–1a, 7–1b and 7–2) and two T-cell epitopes (16–28 aa and 40–52 aa) were analyzed. The smallest number of substitutions was found in the RotaTeq vaccine registered in Russia: from 0 to 3 aa differences at the epitope. The same (from 0 to 3 aa differences at the epitope) was found between the wild-type strains RVA and the Rotavac vaccine. The largest number of amino acid differences was found between the vaccine strain Rotarix and the Nizhny Novgorod G9 strains (from 3 to 10 aa at the epitope). Conclusion. In the present work, based on nucleotide sequences VP7 gene, we provide phylogenetic and comparative analyses of the amino acid composition of antigenic epitopes of G9 RVA isolated in Russia vs rotavirus strains in vaccines RotaTeq, Rotavac and Rotarix. The accumulation of mutations in antigenic epitopes can help the virus to escape the immune response. Continuous molecular monitoring of wild-type RVA strains is necessary for estimation of the possible impact of vaccines on the genotype diversity of the rotavirus population in the wild and to monitor the emergence of novel antigenic variants

ETHNOPSYCHOLINGUISTIC FEATURES OF MASTERING SOCIOLINGUISTIC AND PRAGMATIC COMPONENTS OF FOREIGN LANGUAGE COMPETENCE

The article deals with ethnic and individual psycholinguistic features of students which should be taken into account when mastering sociolinguistic and pragmatic components of foreign language communicative competence. Multicomponent foreign language communicative competence implies successful intercultural speech interaction and mutual understanding, "the ability to act as a secondary linguistic personality in a variety of social situations". Attention to sociolinguistic (ability to take into account social and cultural communication norms) and pragmatic (knowledge of linguistic means) components is due to the specific process of mastering these competences which is characterized by intercultural sensitivity, knowledge of linguistic codes for different social situations, consideration of values, psychological and social identities of communication partners. On the basis of the survey of foreign students, conclusions were drawn about sociolinguistic and pragmatic components mastered by representatives of low-context cultures. The paper attempts to describe ethnopsycholinguistic factors which influence the success of acquiring sociolinguistic and pragmatic components of foreign language communicative competence as a basis for successful communicative and behavioral intercultural interaction. The article suggests methodological recommendations and tasks which contribute to formation of these components, allow the learner to think as representative of the culture of the learned language, i.e. to form a secondary language personality (C) 2019 Published by Future Academ

VIRAL ETIOLOGY ACUTE INTESTINAL INFECTIONS MOLECULAR MONITORING IN CHILDREN’S HOSPITAL

On the territory of the Russian Federation in the overall structure of acute intestinal infections the proportion of viral diarrhea among children varies from 24 to 78% of cases depending on the season. The acute viral intestinal infections etiological confirmation is performed mainly among patients of infectious hospitals. The prevalence of viral acute intestinal infections in non-infectious hospitals, including infections associated with medical care, remains unclear. Currently estimation of viral component in the acute intestinal infections overall structure mainly consists in determination of rotavirus infection prevalence excluding other pathogens. As the part of viral etiology hospital infections epidemiological surveillance in non-infections children’s hospital the study of acute viral intestinal infections etiological structure and molecular genetics characterization of identified enteric viruses is conducted. The syndrome diagnosis of acute intestinal infections cases was introduced — an identification and evaluation of patients with signs of dysfunction of the gastrointestinal tract, that is not related to the underlying disease. A set of laboratory methods included identification of various intestinal pathogens DNA (RNA) by PCR-RT method; genotyping of enteric viruses using sequencing; nucleotide sequence analysis of cDNA fragments using the BLAST software package for identification of closely related strains and an online service for automatic genotyping of noroviruses by Norovirus Genotyping Tool Version 1.0. Alignment of nucleotide sequences and phylogenetic analysis was performed using the software MEGA 5.0. The obtained sequence fragments of the genome was downloaded in GenBank international database. The use of molecular genetics research methods allowed to differentiate viral pathogens of acute intestinal infections and to establish the fact of nosocomial transmission. The proportion of viral etiology acute intestinal infections in patients with clinical signs of intestinal infection, and contact persons was 43.8%. The etiological structure of intestinal virus infections was presented by noroviruses (73.2%) genotypes GII.1, GII.3, GII.4 Sydney 2012, rotaviruses (23.2%) genotypes G4P[8] and G1-IP[8], and adenovirus (1.8%) of the group F and astroviruses (1.8%) genotypes 1 and 2. Among the hospitalized children were 9 cases of viral etiology acute intestinal infections importation, and 66 of cases were of nosocomial origin. Examination of the environment revealed the presence of contamination by enteric viruses in 47.8% of cases

MANIFESTATIONS OF EPIDEMIC PROCESS OF ROTAVIRUS INFECTION IN NIZHNY NOVGOROD IN PRE-VACCINATION PERIOD

Aim. Study the manifestations of epidemic process of rotavirus infection in Nizhny Novgorod in pre-vaccination period to evaluate the possible effect on morbidity for the rotavirus vaccine application introduction. Materials and methods. Rotavirus morbidity data were analyzed for the 12-year period (2005 - 2016), as well as its age and season distribution. Rotavirus genotyping was carried out using multiplex PCR and partial sequencing of VP4 and VP7 genes. Results. RVI morbidity in Nizhny Novgorod was shown to be at a moderate level when specific prophylaxis was not applied, multi-year dynamics for morbidity reflects the all-Russian state. 2015 - 2016 were characterized by intensification of the epidemic process in age groups of organized children (3 - 6 and 7 - 14) and adults. Season increase included December-May. seasonal morbidity maximums in different age groups took place during different months. Genetic structure of Nizhny Novgorod population PV-A during this time was presented by 10 types with G9P[8] (44,4%) dominating. Conclusion. Growth of RVI morbidity in Nizhny Novgorod in 2015 - 2016 and changes in age and season manifestations of the infection took place under the condition of change of the dominating genotype PV-A (G4P[8] to G9P[8])