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Driedonks, T.

Publications and source records attributed to Driedonks, T..

3 recordsLinked to original sources

Viral and host small RNA transcriptome analysis of SARS-CoV-1 and SARS-CoV-2-infected human cells reveals novel viral short RNAs.

RNA viruses have been shown to express various short RNAs, some of which have regulatory roles during replication, transcription, and translation of viral genomes. However, short viral RNAs (svRNAs) generated by SARS-CoV-1 and SARS-CoV-2 remained largely unexplored, mainly due limitations of the widely used library preparation methods for small RNA deep sequencing and corresponding data processing. By analyzing publicly available small RNA-seq datasets, we observed that human cells infected by SARS-CoV-1 or SARS-CoV-2 produce multiple short viral RNAs (svRNAs), ranging in size from 15 to 26 nt and deriving predominantly from (+) RNA strands. In addition, we verified the presence of the five most abundant SARS-CoV-2 svRNAs in SARS-CoV-2-infected human lung adenocarcinoma cells by qPCR. Interestingly, the copy number of the observed SARS-CoV-2 svRNAs dramatically exceeded the expression of previously reported viral miRNAs in the same cells. We hypothesize that the reported SARS-CoV-2 svRNAs could serve as biomarkers for early infection stages due to their high abundance. Finally, we found that both SARS-CoV-1 and SARS-CoV-2 infection induced up- and down-regulation of multiple endogenous human short RNAs that align predominantly to protein-coding and lncRNA transcripts. Interestingly, a significant proportion of short RNAs derived from full-length viral genomes also aligned to various hg38 sequences, suggesting opportunities to investigate regulatory roles of svRNAs during infection. Further characterization of the small RNA landscape of both viral and host genomes is clearly warranted to improve our understanding of molecular events related to infection and to design more efficient strategies for therapeutic interventions as well as early diagnosis.

molecular biology↗

Pharmacokinetics and biodistribution of extracellular vesicles administered intravenously and intranasally to Macaca nemestrina

Extracellular vesicles (EVs) have great potential as novel drug carriers for the treatment of various diseases. These lipid bilayer vesicles are naturally abundant in mammalian tissues and circulation, can be loaded with therapeutic small molecule drugs, (si)RNA, proteins and CRISPR/Cas9, and may be engineered for retention by specific tissues. However, many questions remain on the optimal dosing, administration route, and pharmacokinetics of EVs. Previous studies have addressed biodistribution and pharmacokinetics in rodents, but little evidence is available from larger animals. Here, we investigated the pharmacokinetics and biodistribution of Expi293F-derived EVs labelled with a highly sensitive nanoluciferase reporter (palmGRET) in a non-human primate model (Macaca nemestrina), comparing intravenous (IV) and intranasal (IN) administration over a 125-fold dose range. We report that EVs administered IV had markedly longer circulation times in plasma than previously reported in mice, and were detectable in cerebrospinal fluid (CSF) after 30-60 minutes. Already after one minute following IV administration, we observed EV uptake by PBMCs, most notably B-cells. EVs were detected in liver and spleen within one hour of IV administration. None of the IN doses resulted in readily detectable EV levels in plasma, CSF, or organs, suggesting that IN delivery of EVs in large animals including humans may require reconsideration or pretreatment approaches. Furthermore, EV circulation times strongly decreased after repeated IV administration, possibly due to immune responses and with clear implications for xenogeneic EV-based therapeutics. We hope that our findings from this baseline study in macaques will help to inform future research and therapeutic development of EVs.

pharmacology and toxicology↗

A bacterial extracellular vesicle-based intranasal vaccine against SARS-CoV-2

Several vaccines have been introduced to combat the coronavirus infectious disease-2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Current SARS-CoV-2 vaccines include mRNA-containing lipid nanoparticles or adenoviral vectors that encode the SARS-CoV-2 Spike (S) protein of SARS-CoV-2, inactivated virus, or protein subunits. Despite growing success in worldwide vaccination efforts, additional capabilities may be needed in the future to address issues such as stability and storage requirements, need for vaccine boosters, desirability of different routes of administration, and emergence of SARS-CoV-2 variants such as the Delta variant. Here, we present a novel, well-characterized SARS-CoV-2 vaccine candidate based on extracellular vesicles (EVs) of Salmonella typhimurium that are decorated with the mammalian cell culture-derived Spike receptor-binding domain (RBD). RBD-conjugated outer membrane vesicles (RBD-OMVs) were used to immunize the golden Syrian hamster (Mesocricetus auratus) model of COVID-19. Intranasal immunization resulted in high titers of blood anti-RBD IgG as well as detectable mucosal responses. Neutralizing antibody activity against wild-type and Delta variants was evident in all vaccinated subjects. Upon challenge with live virus, hamsters immunized with RBD-OMV, but not animals immunized with unconjugated OMVs or a vehicle control, avoided body mass loss, had lower virus titers in bronchoalveolar lavage fluid, and experienced less severe lung pathology. Our results emphasize the value and versatility of OMV-based vaccine approaches.

immunology↗