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Motin, V. L.

Publications and source records attributed to Motin, V. L..

2 recordsLinked to original sources

Application of long-read sequencing for genotyping, epigenetic profiling and surveillance of Yersinia pestis isolates from natural foci and disease outbreaks in Central Asia

This study explores the application of long-read sequencing technologies for genotyping, epigenetic profiling, and epidemiological monitoring of Yersinia pestis isolates obtained from natural foci in Central Asia and previous zoonotic outbreaks. Computational tools for genome assembly and genotyping were developed, enabling high-precision identification of both chromosomal and plasmid sequences, including the small cryptic pCKF plasmid. SNP-based genotyping distinguished the major Y. pestis biovars (Antiqua, Medievalis and non-main) and revealed cluster-specific diversity among Medievalis (MED) isolates, identifying a group of strains particularly prone to transmission from rodents to domestic animals and humans, which can be facilitated by the plasmid pCKF. Specific genomic polymorphisms were identified in sub-clades of MED isolates, which allow their identification with high precision. Additionally, comparative epigenomic analysis uncovered strain-specific cytosine methylation patterns at cgGATCG motifs, which may be linked to genome function regulation and adaptation to different hosts and environments. These findings demonstrate the effectiveness of long-read sequencing technologies in revealing both genetic and epigenetic features of bacterial pathogens, contributing to our understanding of the evolutionary mechanisms underlying the emergence and spread of this especially dangerous infection.

microbiology↗

Combinatorial viral vector-based and live-attenuated vaccines without an adjuvant to generate broader immune responses to effectively combat pneumonic plague

Mice immunized with a combination of an adenovirus vector (Ad5-YFV) and live-attenuated (LMA)-based vaccines were evaluated for protective efficacy against pneumonic plague. While the Ad5-YFV vaccine harbors a fusion cassette of three genes encoding YscF, F1, and LcrV, LMA represents a mutant of parental Yersinia pestis CO92 deleted for genes encoding Lpp, MsbB, and Ail. Ad5-YFV and LMA were either administered simultaneously (1-dose regimen) or 21 days apart in various order and route of administration combinations (2-dose regimen). The 2-dose regimen induced robust immune responses to provide full protection to animals against parental CO92 and its isogenic F1 (CAF-)-deletion mutant challenges during both short- and long-term studies. Mice intranasally (i.n.) immunized with Ad5-YFV first followed by LMA (i.n. or intramuscularly [i.m.]) had higher T- and B-cell proliferative responses and LcrV antibody titers than those in mice vaccinated with LMA (i.n. or i.m.) first ahead of Ad5-YFV (i.n.) during the long-term study. Specifically, the needle- and adjuvant-free vaccine combination (i.n.) is ideal for use in plague endemic regions. Conversely, with a 1-dose regimen, mice vaccinated with Ad5-YFV i.n. and LMA by the i.m. route provided complete protection to animals against CO92 and its CAF- mutant challenges, and elicited Th1/Th2, as well as Th17 responses, thus suitable for emergency vaccination during a plague outbreak or bioterrorist attack. This is a first study in which a viral vector-based and live-attenuated vaccines were effectively used in combination representing adjuvant- and/or needle- free immunization, with each vaccine triggering a distinct cellular immune response. ImportanceYersinia pestis, the causative agent of plague, is a Tier-1 select agent and a re-emerging human pathogen. A 2017 outbreak in Madagascar with >75% of cases being pneumonic and 8.6% causalities emphasized the importance of the disease. The World Health Organization has indicated an urgent need to develop new generation subunit and live-attenuated plague vaccines. We have developed a subunit vaccine including three components (YscF, F1, and LcrV) using an adenovirus platform (Ad5-YFV). In addition, we have deleted virulence genes of Y. pestis (e.g., lpp, msbB, and ail) to develop a live-attenuated vaccine (LMA). Both of these vaccines generated robust humoral and cellular immunity and were highly efficacious in several animal models. We hypothesized the use of a heterologous prime-boost strategy or administrating both vaccines simultaneously could provide an adjuvant- and/or a needle- free vaccine(s) which have attributes of both vaccines for use in endemic regions and during an emergency situation.

microbiology↗