Alveolar type 2 (AT2) cells are stem cells of the alveolar epithelia. Previous genetic lineage tracing studies reported multiple cellular origins for AT2 cells after injury. However, conventional lineage tracing based on Cre-loxP has the limitation of non-specific labeling. Here, we introduced a dual recombinase-mediated intersectional genetic lineage tracing approach, enabling precise investigation of AT2 cellular origins during lung homeostasis, injury, and repair. We found AT1 cells, being terminally differentiated, did not contribute to AT2 cells after lung injury and repair. Distinctive yet simultaneous labeling of club cells, bronchioalveolar stem cells (BASCs), and existing AT2 cells revealed the exact contribution of each to AT2 cells post-injury. Mechanistically, Notch signaling inhibition promotes BASCs but impairs club cells' ability to generate AT2 cells during lung repair. This intersectional genetic lineage tracing strategy with enhanced precision allowed us to elucidate the physiological role of various epithelial cell types in alveolar regeneration following injury.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.cell.2024.03.010 | DOI Listing |
Am J Respir Cell Mol Biol
January 2025
Duke Medicine, Medicine, Durham, North Carolina, United States.
Becoming more frequent due to climate change, ozone (O) exposures can cause lung injury. Alveolar type 2 (AT2) cells and hyaluronan (HA), a matrix component, are critical to repairing lung injury and restoring homeostasis. Here, we define the impact of HA on AT2 cells following acute O exposure.
View Article and Find Full Text PDFmBio
December 2024
Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, North Carolina, USA.
Unlabelled: Respiratory epithelial cells can survive direct infection by influenza viruses, and the long-term consequences of that infection have been characterized in a subset of proximal airway cell types. The impact on the cells that survive viral infection in the distal lung epithelia, however, is much less well-characterized. Utilizing a Cre-expressing influenza B virus (IBV) and a lox-stop-lox tdTomato reporter mouse model, we identified that alveolar type 2 (AT2) pneumocytes, a progenitor cell type in the distal lung, can survive viral infection.
View Article and Find Full Text PDFBrain Behav Immun
December 2024
Wolfson Sensory, Pain and Regeneration Centre, King's College London, Guy's Campus, London Bridge, London SE1 1UL, UK. Electronic address:
Angiotensin II is well known to have an important influence on blood pressure, mediated via the angiotensin II type 1 receptor (AT1R), and more recent studies have shown that angiotensin II may play an important additional role in eliciting pain via a distinct action at the angiotensin II type 2 receptor (AT2R). Signalling pathways that link activation of AT2R to a sensation of pain are, however, incompletely understood. Here we use rodent inflammatory pain models to confirm that selective activation of AT2R triggers aversive responses, and that these are abolished by either antagonism or genetic deletion of AT2R.
View Article and Find Full Text PDFJCI Insight
December 2024
Division of Pulmonary and Sleep Medicine, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, United States of America.
Hermansky-Pudlak syndrome (HPS) is a genetic disorder of endosomal protein trafficking associated with pulmonary fibrosis in specific subtypes, including HPS-1 and HPS-2. Single mutant HPS1 and HPS2 mice display increased fibrotic sensitivity while double mutant HPS1/2 mice exhibit spontaneous fibrosis with aging, which has been attributed to HPS mutations in alveolar epithelial type II (AT2) cells. We utilized HPS mouse models and human lung tissue to investigate mechanisms of AT2 cell dysfunction driving fibrotic remodeling in HPS.
View Article and Find Full Text PDFInt J Mol Sci
November 2024
Department of Oral Biology, Semmelweis University, H-1089 Budapest, Hungary.
NMDA receptors in the prefrontal cortex (PFC) play a crucial role in cognitive functions. Previous research has indicated that angiotensin II (Ang II) affects learning and memory. This study aimed to examine how Ang II impacts NMDA receptor activity in layer V pyramidal cells of the rat PFC.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!