Biology subjects

Giobbe, G. G.

Publications and source records attributed to Giobbe, G. G..

6 recordsLinked to original sources

bioRxiv2025

WS6 enables scalable ex vivo expansion and gene editing of epithelial basal stem cells

Modeling human epithelial diseases and developing cell-based therapies require robust methods to expand and manipulate epithelial stem and progenitor cells in vitro. Basal stem/progenitor cells from stratified epithelia can be expanded in 3T3-J2 fibroblast feeder cell co-culture systems, and the addition of the ROCK inhibitor Y-27632 enhances proliferation and culture longevity, a phenomenon described as conditional reprogramming. Here, we present a method incorporating the small molecule WS6 to further improve the proliferation and lifespan of cultured epithelial cells from multiple tissues, including airway, skin, and thymus. Cells maintained in this medium ( EpMED; FAD+Y+WS6) retain basal stem/progenitor cell identity and function, including the capacity to differentiate. We demonstrate their capacity to engraft in vivo in a tracheal transplantation model. In a second application, we generate clonal CRISPR-Cas9 genome edited nasal cultures, introducing targeted knockouts of DNAH5 or DNAI2 to create primary ciliary dyskinesia disease models. We anticipate that our method will have broad applications in epithelial cell biology, disease modeling, and regenerative medicine, while reducing reliance on immortalized or cancer cell lines and animal experimentation.

cell biology↗

bioRxiv2024

Human Gastric Multi-Regional Assembloids Favour Functional Parietal Maturation and Allow Modelling of Antral Foveolar Hyperplasia

Patient-derived human organoids have the remarkable capacity to self-organise into more complex structures. However, to what extent gastric organoids can recapitulate human stomach physiological functions remain unexplored. Here, we report how region-specific gastric organoids can self-assemble into complex multi-regional assembloids showing functional response to drugs targeting the ATPase H+/K+ pump. The assembloids show preserved fundus, body, and antrum regional identity, and gastric-specific crosstalk pathways arise. The increased complexity and cross-communication between the different gastric regions, allow for the emergence of the elusive parietal cell type, responsible for the production of gastric acid, with functional response to drugs targeting the ATPase H+/K+ pump. Remarkably, we generated assembloids from PMM2-HIPKD-IBD paediatric patients (Phosphomannomutase 2 - Hyperinsulinemic hypoglycaemia and autosomal recessive polycystic kidney disease - Inflammatory bowel disease), a genetic condition found to be associated with unusual antral foveolar hyperplasia and hyperplastic polyposis. The cellular mechanisms behind such phenomena are poorly understood, and an exhaustive experimental model is needed. The {Delta}PMM2 multi-regional assembloid we have generated efficiently recapitulates hyperplastic-like antral regions, with decreased mucin secretion and glycosylated ATP4b, which results in impaired gastric acid secretion. Multi-regional gastric assembloids, generated using adult-stem cell-derived organoids, successfully recapitulate the structural and functional characteristics of the human stomach, offering a promising tool for studying gastric epithelial interactions and disease mechanisms previously challenging to investigate in primary models.

cell biology↗

bioRxiv2023

Single cell-guided prenatal derivation of primary epithelial organoids from the human amniotic and tracheal fluids.

Despite advances in prenatal diagnosis, it is still difficult to predict severity and outcomes of many congenital malformations. New patient-specific prenatal disease modelling may optimise personalised prediction. We and others have described the presence of mesenchymal stem cells in amniotic fluid (AFSC) that can generate induced pluripotent stem cells (iPSCs). The lengthy reprogramming processes, however, limits the ability to define individual phenotypes or plan prenatal treatment. Therefore, it would be advantageous if fetal stem cells could be obtained during pregnancy and expanded without reprogramming. Using single cell analysis, we characterised the cellular identities in amniotic fluid (AF) and identified viable epithelial stem/progenitor cells of fetal intestinal, renal and pulmonary origin. With relevance for prenatal disease modelling, these cells could be cultured to form clonal epithelial organoids manifesting small intestine, kidney and lung identity. To confirm this, we derived lung organoids from AF and tracheal fluid (TF) cells of Congenital Diaphragmatic Hernia (CDH) fetuses and found that they show differences to non-CDH controls and can recapitulate some pathological features of the disease. Amniotic Fluid Organoids (AFO) allow investigation of fetal epithelial tissues at clinically relevant developmental stages and may enable the development of therapeutic tools tailored to the fetus, as well as to predicting the effects of such therapies.

cell biology↗

bioRxiv2023

Lung viral infection modelling in a bioengineered whole-organ

Lung infections are one of the leading causes of death worldwide, and this situation has been exacerbated by the emergence of COVID-19. Pre-clinical modelling of viral infections has relied on cell cultures that lack 3D structure and the context of lung extracellular matrices. Here, we propose a bioreactor-based, whole-organ lung model of viral infection. The bioreactor takes advantage of an automated system to achieve efficient decellularization of a whole rat lung, and recellularization of the scaffold using primary human bronchial cells. Automatization allowed for the dynamic culture of airway epithelial cells in a breathing-mimicking setup that led to an even distribution of lung epithelial cells throughout the distal regions. In the sealed bioreactor system, we demonstrate proof-of-concept for viral infection with the engineered lung by infecting primary human airway epithelial cells. Moreover, to assess the possibility of drug screening in this model, we demonstrate the efficacy of the broad-spectrum antiviral Remdesivir. This whole-organ scale lung infection model represents a step towards modelling viral infection of human cells in a 3D context, providing a powerful tool to investigate the mechanisms of the early stages of pathogenic infections and the development of effective treatment strategies for respiratory diseases.

bioengineering↗

bioRxiv2022

Synchronisation of apical constriction and cell cycle progression is a conserved behaviour of pseudostratified neuroepithelia informed by their tissue geometry

Neuroepithelial cells balance tissue growth requirement with the morphogenetic imperative of closing the neural tube. They apically constrict to generate mechanical forces which elevate the neural folds, but are thought to apically dilate during mitosis. However, we previously reported that mitotic neuroepithelial cells in the mouse posterior neuropore have smaller apical surfaces than non-mitotic cells. Here, we document progressive apical enrichment of non-muscle myosin-II in mitotic, but not non-mitotic, neuroepithelial cells with smaller apical areas. Live-imaging of the chick posterior neuropore confirms apical constriction synchronised with mitosis, reaching maximal constriction by anaphase, before division and re-dilation. Mitotic apical constriction amplitude is significantly greater than interphase constrictions. To investigate conservation in humans, we characterised early stages of iPSC differentiation through dual SMAD-inhibition to robustly produce pseudostratified neuroepithelia with apically enriched actomyosin. These cultured neuroepithelial cells achieve an equivalent apical area to those in mouse embryos. iPSC-derived neuroepithelial cells have large apical areas in G2 which constrict in M phase and retain this constriction in G1/S. Given that this differentiation method produces anterior neural identities, we studied the anterior neuroepithelium of the elevating mouse mid-brain neural tube. Instead of constricting, mid-brain mitotic neuroepithelial cells have larger apical areas than interphase cells. Tissue geometry differs between the apically convex early midbrain and flat posterior neuropore. Culturing human neuroepithelia on equivalently convex surfaces prevents mitotic apical constriction. Thus, neuroepithelial cells undergo high-amplitude apical constriction synchronised with cell cycle progression but the timing of their constriction if influenced by tissue geometry.

cell biology↗

bioRxiv2020

SARS-CoV-2 infection and replication in human fetal and pediatric gastric organoids

Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a global public health emergency. COVID-19 typically manifests as a respiratory illness but an increasing number of clinical reports describe gastrointestinal (GI) symptoms. This is particularly true in children in whom GI symptoms are frequent and viral shedding outlasts viral clearance from the respiratory system. By contrast, fetuses seem to be rarely affected by COVID-19, although the virus has been detected in placentas of affected women. These observations raise the question of whether the virus can infect and replicate within the stomach once ingested. Moreover, it is not yet clear whether active replication of SARS-CoV-2 is possible in the stomach of children or in fetuses at different developmental stages. Here we show the novel derivation of fetal gastric organoids from 8-21 post-conception week (PCW) fetuses, and from pediatric biopsies, to be used as an in vitro model for SARS-CoV-2 gastric infection. Gastric organoids recapitulate human stomach with linear increase of gastric mucin 5AC along developmental stages, and expression of gastric markers pepsinogen, somatostatin, gastrin and chromogranin A. In order to investigate SARS-CoV-2 infection with minimal perturbation and under steady-state conditions, we induced a reversed polarity in the gastric organoids (RP-GOs) in suspension. In this condition of exposed apical polarity, the virus can easily access viral receptor angiotensin-converting enzyme 2 (ACE2). The pediatric RP-GOs are fully susceptible to infection with SARS-CoV-2, where viral nucleoprotein is expressed in cells undergoing programmed cell death, while the efficiency of infection is significantly lower in fetal organoids. The RP-GOs derived from pediatric patients show sustained robust viral replication of SARS-CoV-2, compared with organoids derived from fetal stomachs. Transcriptomic analysis shows a moderate innate antiviral response and the lack of differentially expressed genes belonging to the interferon family. Collectively, we established the first expandable human gastric organoid culture across fetal developmental stages, and we support the hypothesis that fetal tissue seems to be less susceptible to SARS-CoV-2 infection, especially in early stages of development. However, the virus can efficiently infect gastric epithelium in pediatric patients, suggesting that the stomach might have an active role in fecal-oral transmission of SARS-CoV-2.

cell biology↗