Session topic

18:45–18:50

Title: Modeling gastrointestinal infection of SARS-CoV-2 and its inhibition in human pluripotent stem-cell derived intestinal organoids
ID: PS 44
Type: Poster session
Talk time: 3 + 2 min
Session: Poster session 1
Zoonoses and emerging viruses

Speaker: Rüdiger Groß (Ulm/DE)


Abstract - Text

Abstract text (incl. references and figure legends)

SARS-CoV-2 has spread worldwide and poses a severe health risk. While most patients exhibit mild symptoms, pneumonia and respiratory insufficiency as well as extrapulmonary dissemination may lead to organ failure and death. Up to 50% of patients show gastrointestinal symptoms like diarrhea or nausea, associated with prolonged symptoms and increased severity of the disease. Thus, models to explore SARS-CoV-2 in the human gastrointestinal tract and assess treatment regimens are urgently needed. Human intestinal organoids derived from pluripotent stem cells (PSC-HIOs) closely mimic the human intestinal architecture due to their complexity. This model was already applied successfully as faithful disease models for other gastrointestinal infections. We thus here evaluate this model as for SARS-CoV-2 infection and drug testing. For this purpose, gastrointestinal organoids were differentiated from human embryonic stem cells in vitro. Expression of SARS-CoV-2 entry factors ACE2 and TMPRSS2 was analyzed by immunohistochemistry in sections of patient-derived material from the GI tract and in organoids. Organoids were subsequently infected with SARS-CoV-2 and replication assessed by measuring viral RNA and staining for viral proteins alongside cell type-specific markers. Lastly, drugs were evaluated for their potential to inhibit infection in this complex model compared to conventional intestinal cell culture. ACE2 and SARS-CoV-2 spike protein priming protease TMPRSS2 showed broad expression in the gastrointestinal tract with highest levels in the intestine, the latter faithfully recapitulated by PSC-HIOs. Organoids could be readily infected with SARS-CoV-2 followed by viral spread across entire PSC-HIOs, subsequently leading to organoid deterioration. However, SARS-CoV-2 spared goblet cells lacking ACE2 expression. Importantly, Remdesivir effectively inhibited SARS-CoV-2 infection dose-dependently at low micromolar concentration and rescued PSC-HIO morphology, however substantially higher dosages were required compared to 2D culture of a intestinal cell line (Caco-2). Peptidic fusion inhibitor EK-1 similarly prevented infection, while the H2-blocker famotidine, discussed for possible in vivo effects against SARS-COV-2, was entirely inactive. In conclusion, PSC-HIOs were established and verified as a valuable tool to study SARS-CoV-2 in the gut and to assess drug treatment efficiencies, revealing differences in drug efficacy compared to simpler models.