Bosma arhinia microphthalmia syndrome (BAMS) is a rare genetic disorder resulting in babies born without a nose, along with eye and reproductive anomalies. Our guests today investigated the developmental basis of this distinct defect using induced pluripotent stem cells (iPSCs) derived from patients with BAMS. They assess the differentiation potential of BAMS patient-derived iPSCs into cranial placode cells, a group of progenitor cells that contributes to the formation of the nasal epithelium. This allowed them to study the behavior of the nasal epithelial cells during early development. Their work uncovered cellular mechanisms underlying BAMS and provided new insights into the developmental processes that shape the human nose. 

Acute respiratory distress syndrome (ARDS) induced by COVID-19 was a leading cause of severe illness and death during the pandemic, driven by an intense innate immune response, hyperinflammation, and a decrease in lymphocytes. Mesenchymal stromal cells (MSCs) represent a potential therapeutic option for ARDS due to their ability to modulate the immune system and inflammation. Our guests report results from a Health Canada–regulated Phase I and Phase II trials evaluating freshly cultured umbilical cord–derived MSCs in patients with COVID-19-related ARDS, including assessments of safety, maximum feasible tolerated dose, and preliminary efficacy. Their work explores a therapeutic strategy to improve ARDS outcomes using MSCs, which will be important for optimizing and targeting future cellular therapies.