Biology subjects

Jardim, A. C. G.

Publications and source records attributed to Jardim, A. C. G..

3 recordsLinked to original sources

bioRxiv2026

Screening of MMV open-source libraries using Bunyamwera virus as a model reveals inhibitors of Oropouche virus infection

Arboviral infections remain a major public health concern in tropical and subtropical regions, where environmental and socioeconomic conditions facilitate the circulation of diverse RNA viruses, including over 350 members of the recently renamed Peribunyaviridae family. In this regard, Oropouche virus (OROV) has caused explosive outbreaks in the Amazon region and shows wider distribution in Brazil, with confirmed neurological infections and fatalities in 2024. The absence of effective antiviral therapies highlights an urgent need for the discovery of anti-OROV drugs. In this work we evaluated the antiviral potential of the Pandemic Response Box and Global Health Priority Box libraries from Medicines for Malaria Venture (MMV) against OROV, using a well-established Bunyamwera virus (BUNV) system, widely used as a prototype of the Peribunyaviridae family, expressing the reporter gene eGFP. A screening protocol based on fluorescent reporter gene detection by live cell imaging was employed. 9 compounds were identified with significant activity against BUNV-eGFP with 3 being highlighted as the most promising hits: Trimetrexate, GSK-983 and MMV1634385. These compounds were validated by testing for activity against OROV, and in these assays, GSK-983 exhibited the lowest EC50 value and consequently the highest selectivity index. Future studies should evaluate the antiviral efficacy of GSK-983 and assess its pharmacokinetic profile. Furthermore, our results indicate that our approach employing BUNV-eGFP as a model against OROV can lead to the discovery of promising and interesting hit compounds, thereby providing a validated screening approach for future antivirals against Oropouche fever.

microbiology↗

bioRxiv2025

Development of enterovirus trans-encapsidation assays as tools to understand viral entry.

Enteroviruses (EVs) are globally important human and animal pathogens which cause a diverse spectrum of disease, ranging from febrile illness to paralysis. Despite decades of research, parts of the EV lifecycle remain poorly understood. Replicons, in which reporter genes replace the structural protein coding region, have proved useful for the study of EV biology. However, it is not possible to study the molecular mechanism(s) of entry, capsid uncoating and genome release without the production of virus particles. To utilise the benefits provided by replicons for the study of viral cell entry, it would be necessary to supply the structural proteins in trans. Here, we present an EV trans-encapsidation (TE) system in which reporter replicons are transfected into cells modified to express the viral structural proteins. The nascent replicons are packaged in trans to form virus particles containing fluorescent or luminescent replicon genomes. This enables the real-time assessment of EV entry and replication through quantification of fluorescence using live-cell imaging. We demonstrate that these TE particles are biologically accurate proxies to EVA71 virions and show utility for the study of EV entry, uncoating and replication. Additionally, we demonstrate the use of TE particles as platforms for drug discovery and immunological screening, applicable to the development of antiviral therapeutics and assessment of immunisation outcomes.

microbiology↗

bioRxiv2019

Extraction-free direct PCR from dried serum spots permits HBV genotyping and RAS identification by Sanger and minION sequencing

In order to achieve the commitment made by the World Health Organisation to eliminate viral hepatitis by 2030, it is essential that clinicians can obtain basic sequencing data for hepatitis B virus (HBV) infected patients. While accurate diagnosis of HBV is achievable in most clinical settings, genotyping and identification of resistance-associated substitutions (RAS) present a practical challenge in regions with limited healthcare and biotechnology infrastructure. Here we outline two workflows for generating clinically relevant HBV sequence data directly from dried serum spot (DSS) cards without DNA extraction using either Sanger, or the portable MinION sequencing platforms. Data obtained from the two platforms were highly consistent and allowed determination of HBV genotype and RAS. This is the first demonstration of MinION sequencing from DSS, illustrating the broad utility of this sequencing technology. We demonstrated the clinical application of this technology using sera sampled on DSS cards obtained from both Iraq and Brazil. The sample stability provided by DSS cards, combined with the rapid PCR and sequencing protocols will enable regional/national centres to provide information relevant to patient management. By providing viable workflows for both the Sanger and MinION sequencing platforms, which vary greatly in the infrastructure and expertise required, we demonstrate that MinION sequencing is a viable method for HBV genotyping in resource-limited settings. These workflows could also be applied to sequencing of other blood borne DNA viruses and bacterial pathogens.

microbiology↗