Biology subjects

Ngoy, S.

Publications and source records attributed to Ngoy, S..

4 recordsLinked to original sources

bioRxiv2024

A wide diversity of viruses detected in African mammals involved in the wild meat supply chain

The processes involved in acquiring, trading, preparing, and consuming wild meat pose significant risks for the emergence of zoonotic infectious diseases. Several major viral outbreaks have been directly linked to the wild meat supply chain, yet our knowledge of the virome in many mammals involved in this chain remains limited and disproportionately focused on certain mammalian taxa and pathogens. This report presents the findings of a metagenomic viral screening of 99 specimens belonging to 27 wild African mammal species and one domesticated species, all traded for their meat. The study focuses on tissue and swab samples collected from various regions in the Democratic Republic of the Congo and in Brussels, Belgium. A total of fifteen virus strains were detected, belonging to the families Arteriviridae, Retroviridae and Sedoreoviridae (primates), Picobirnaviridae (primates and rodents), Picornaviridae (rodents), Hepadnaviridae (hyrax), Orthoherpesviridae (artiodactylid and carnivore) and Spinareoviridae (carnivore). Several strains were detected in mammalian hosts for the first time, expanding their host range and genetic diversity. Of note is the presence of viruses genetically related to recognised zoonotic pathogens, i.e., human picobirnavirus (Orthopicobirnavirus hominis) (primates and rodents), simian foamy viruses (Simiispumavirus) (primates), and rotavirus A (Rotavirus alphagastroenteritidis) (primates). The presence of these viruses in primates is concerning as non-human primates are phylogenetically closely related to humans, which can facilitate interspecies viral transmission. These findings underscore the high diversity of mammalian viruses and the potential risk of human infection through cross-species transmission during the close interactions with wildlife in the wild meat supply chain.

genomics↗

bioRxiv2024

Assessing Ebola Virus Circulation in the Tshuapa Province (Democratic Republic of the Congo): A One Health Investigation of Wildlife and Human Interactions

The wildlife reservoir and spillover mechanisms of the Ebola virus remain elusive despite extensive research efforts in endemic areas. This study employed a One Health approach to examine the virus circulation in wildlife and the associated human exposure risks in the Tshuapa province of the Democratic Republic of the Congo. In 2021, we collected 1015 samples from 888 animals, predominantly small mammals, and 380 inhabitants of Inkanamongo village, the site of an Ebola virus disease outbreak in 2014. These samples were screened for evidence of current (RNA) or past (IgG antibodies) Ebola virus infections. We also conducted interviews with 167 individuals in the surrounding districts to assess their interactions with wildlife. While no Ebola virus RNA was detected in the wildlife samples, anti-orthoebolavirus IgG antibodies were found in 13 bats and 38 rodents. Among the human participants, 120 individuals had IgG antibodies against at least one orthoebolavirus antigen, with 12 showing seropositivity for two antigens of the same orthoebolavirus, despite not having a prior Ebola disease diagnosis. Furthermore, over 50% of respondents reported frequent visits to the forest to hunt a variety of wild animals, particularly ungulates and rodents, which could account for occasional viral spillovers. The absence of active Ebola virus circulation in wildlife may reflect seasonal patterns in reservoir ecology, like those observed in bats. Similarly, seasonal human activities, like hunting and foraging, may result in periodic exposure risks. These findings highlight the importance of continuous, multidisciplinary surveillance to monitor changes in seasonal spillover risks.

molecular biology↗

bioRxiv2023

The evolutionary history of hepaciviruses

In the search for natural reservoirs of hepatitis C virus (HCV), a broad diversity of non-human viruses within the Hepacivirus genus has been uncovered. However, the evolutionary dynamics that shaped the diversity and timescale of hepaciviruses evolution remain elusive. To gain further insights into the origins and evolution of this genus, we screened a large dataset of wild mammal samples (n = 1,672) from Africa and Asia, and generated 34 full-length hepacivirus genomes. Phylogenetic analysis of these data together with publicly available genomes emphasizes the importance of rodents as hepacivirus hosts and we identify 13 rodent species and 3 rodent genera (in Cricetidae and Muridae families) as novel hosts of hepaciviruses. Through co-phylogenetic analyses, we demonstrate that hepacivirus diversity has been affected by cross-species transmission events against the backdrop of detectable signal of virus-host co-divergence in the deep evolutionary history. Using a Bayesian phylogenetic multidimensional scaling approach, we explore the extent to which host relatedness and geographic distances have structured present-day hepacivirus diversity. Our results provide evidence for a substantial structuring of mammalian hepacivirus diversity by host as well as geography, with a somewhat more irregular diffusion process in geographic space. Finally, using a mechanistic model that accounts for substitution saturation, we provide the first formal estimates of the timescale of hepacivirus evolution and estimate the origin of the genus to be about 22 million years ago. Our results offer a comprehensive overview of the micro- and macroevolutionary processes that have shaped hepacivirus diversity and enhance our understanding of the long-term evolution of the Hepacivirus genus. SignificanceSince the discovery of Hepatitis C virus, the search for animal virus homologues has gained significant traction, opening up new opportunities to study their origins and long-term evolutionary dynamics. Capitalizing on a large-scale screening of wild mammals, and genomic sequencing, we expand the novel rodent host range of hepaciviruses and document further virus diversity. We infer a significant influence of frequent cross-species transmission as well as some signal for virus-host co-divergence, and find comparative host and geographic structure. We also provide the first formal estimates of the timescale of hepaciviruses indicating an origin of about 22 million years ago. Our study offers new insights in hepacivirus evolutionary dynamics with broadly applicable methods that can support future research in virus evolution.

microbiology↗

bioRxiv2022

Epicardial reservoir-enabled multidose delivery of exogenous FSTL1 leads to improved cardiac function, healing, and angiogenesis.

Epicardial delivery of human follistatin-like 1 protein (FSTL1) induces significant cardiac benefit following a myocardial infarction (MI). However, the optimal dosing regimen for maximal therapeutic benefit has not yet been elucidated. To investigate the impact of multiple FSTL1 doses, without the confounding effects of multiple surgical procedures for multidose delivery, alternative delivery strategies are needed. Here, we use an epicardial reservoir that allows non-invasive delivery of additional doses after implantation to investigate the impact of single, double, and triple FSTL1 dose regimens in a rat model of MI. Multidose delivery of FSTL1 improves ejection fraction (3 doses), fractional shortening (1, 2 and 3 doses), and chamber stiffness (2 doses) 28 days after MI. Histologically, multiple FSTL1 doses increase ventricular wall thickness (2 and 3 doses) and reduce infarct size (1, 2, and 3 doses). We also demonstrate a dose-dependent increase in blood vessel number and density in the infarct zone, with three FSTL1 doses leading to the highest improvements. This study shows that multidose delivery of FSTL1 improves cardiac function, healing, and angiogenesis following MI. The epicardial delivery platform used here may be essential in optimizing dosing regimens of various bioagent combinations for a range of clinical indications.

bioengineering↗