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Kardia, E.

Publications and source records attributed to Kardia, E..

3 recordsLinked to original sources

Gene-Corrected Basal Cells Restore CFTR In Vitro; Transplants Regenerate Epithelium in a Preclinical Sinus Model

BackgroundCystic fibrosis (CF) is caused by mutations in the CFTR gene, leading to epithelial dysfunction and progressive lung disease. Although CFTR modulators have transformed care, [~]10% of people with CF remain without effective therapy. Durable, mutation-agnostic approaches are urgently needed. MethodWe used a lentiviral (LV) vector to deliver wild-type CFTR to airway basal cells derived from 13 paediatric CF participants with a range of genotypes. Transduced cells were assessed for transgene expression, epithelial differentiation, and CFTR function using air-liquid interface (ALI) cultures. Separately, to evaluate regenerative capacity in vivo, LVGFP-transduced rabbit airway basal cells were transplanted into the denuded nasal septum of healthy New Zealand white rabbits using a biocompatible scaffold. ResultsTransduced basal cells retained multilineage differentiation capacity, forming well-organized, pseudostratified epithelium with intact barrier function and ciliary activity. CFTR channel activity was restored to levels comparable to or exceeding those achieved with elexacaftor/tezacaftor/ivacaftor (ETI), including in individuals with nonsense mutations. Combined CFTR transduction plus ETI treatment showed additive benefit. In vivo, transplanted rabbit basal cells engrafted and differentiated to regenerate a mucociliary epithelium, with improved nasal potential difference and mucociliary clearance compared to scaffold-only controls. ConclusionOur study demonstrates that LV-mediated CFTR gene addition restores CFTR function in vitro across genotypes and supports epithelial regeneration in a clinically relevant animal airway model. This two-part platform offers a scalable path toward cell therapies for all people with CF and may have broader applications in upper airway epithelial repair.

cell biology↗

Hepatobiliary organoids derived from leporids support the replication of hepatotropic lagoviruses

Lagoviruses, family Caliciviridae, are some of the most virulent vertebrate viruses known. They infect leporids, i.e., rabbits (Oryctolagus spp.), hares (Lepus spp.) and cottontails (Sylvilagus spp.) and rapidly kill over 95% of susceptible animals. Pathogenic lagoviruses are hepatotropic and induce a fulminant hepatitis that typically leads to disseminated intravascular coagulation within 24-72 hours of infection. However, the pathophysiological mechanisms governing this extreme phenotype and other aspects of the fundamental biology of these viruses are poorly understood due to a lack of cell culture systems. Here, we report on a robust and reliable ex vivo model for the cultivation of hepatotropic lagoviruses. We show that three rabbit haemorrhagic disease virus (RHDV) variants, RHDV1, RHDV2 and RHDVa-K5, replicate in monolayer cultures derived from rabbit hepatobiliary organoids. Viral replication was demonstrated by a (i) increase in viral RNA levels of greater than one log10 over a 23-hour period, (ii) detection of viral structural and non-structural proteins, and (iii) detection of double-stranded RNA viral replication intermediates. Furthermore, we generated hepatobiliary organoids from a feral cat (Felis domesticus), a wild mouse (Mus musculus) and a European brown hare (Lepus europaeus) and showed that monolayer cultures derived from the cat and mouse organoids were not permissive for lagovirus infection, while those derived from the hare organoids only supported replication of RHDV2, recapitulating the species tropism that has been observed with these viruses. Our organoid culture system will facilitate future studies into the molecular biology of lagoviruses, which will have considerable import for the conservation of endangered leporid species in Europe and North America and the biocontrol of overabundant rabbit populations in Australia and New Zealand.

microbiology↗

Isolation, culture and maintenance of rabbit intestinal organoids, and organoid-derived cell monolayers

Organoids emulate many aspects of their parental tissue and have been used to study pathogen-host interactions, tissue development and regeneration, metabolic diseases, and other complex biological processes. Here, we report a robust protocol for the isolation, maintenance and differentiation of rabbit small intestinal organoids and organoid-derived cell monolayers. We also report conditions that sustain an intestinal stem cell population in spheroid culture. Rabbit intestinal spheroids and monolayer cultures propagated and expanded most efficiently in L-WRN-conditioned medium that contained the signalling factors Wnt, R-spondin and Noggin, and that had been supplemented with ROCK and TGF-{beta} inhibitors. Organoid and monolayer differentiation was initiated by switching to a medium that contained less of the L-WRN-conditioned medium and was supplemented with ROCK and Notch signalling inhibitors. Using immunofluorescence staining and RT-qPCR, we demonstrate that organoids contained enterocytes, enteroendocrine cells, goblet cells and Paneth cells. These findings demonstrate that our rabbit intestinal organoids have many of the multi-cellular characteristics of, and closely resemble, an intestinal epithelium. This newly established organoid culture system will provide a useful tool to study rabbit gastrointestinal physiology and disease. For example, organoids and organoid-derived cells may be used to propagate and study caliciviruses and other enterotropic pathogens that cannot be grown in conventional cell culture systems.

cell biology↗