Notch2 Is Required for Inflammatory Cytokine-Driven Goblet Cell Metaplasia in the Lung

Abstract

The balance and distribution of epithelial cell types is required to maintain tissue homeostasis. A hallmark of airway diseases is epithelial remodeling, leading to increased goblet cell numbers and an overproduction of mucus. In the conducting airway, basal cells act as progenitors for both secretory and ciliated cells. To identify mechanisms regulating basal cell fate, we developed a screenable 3D culture system of airway epithelial morphogenesis. We performed a high-throughput screen using a collection of secreted proteins and identified inflammatory cytokines that specifically biased basal cell differentiation toward a goblet cell fate, culminating in enhanced mucus production. We also demonstrate a specific requirement for Notch2 in cytokine-induced goblet cell metaplasia in vitro and in vivo. We conclude that inhibition of Notch2 prevents goblet cell metaplasia induced by a broad range of stimuli and propose Notch2 neutralization as a therapeutic strategy for preventing goblet cell metaplasia in airway diseases.

Take a deep breath and digest the material: organoids and biomaterials of the respiratory and digestive systems

“…[118] Both the primary tissue-derived organoids and the hPSCderived branched lung organoids contained mature cell types, but overall, these tissues lacked a proper pseudostratified epithelium. [112,[119][120][121][122][123][124] On the other hand, scaffold-transplanted lung organoids derived from hPSCs formed a tube that was organized into a pseudostratified epithelium similar to the adult airway. However, this tissue organization could not be generated in vitro.…”

“…Here, the basal cells form cyst structures that contain the basal cells along with other mature cell types of the airway. [112,[119][120][121][122][123][124][125] Recently, a cell surface marker specific to NKX2.1+ lung progenitors was discovered and used to sort out NKX2.1+ lung progenitors from hPSC-derived lung cultures using flow cytometry. [126,127] The single cells were placed in a Matrigel droplet overlaid with airway-specific media, which resulted in airway cysts that contain basal cells and a few other mature epithelial airway cells.…”

“…[126] Both the hPSC and primary basal cell airway cysts contain a single layer of epithelial cells that contained basal cells and other mature airway cells. [112,[119][120][121][122][123][124]126] Airway models have also been derived from a cluster of hPSC-derived lung progenitors and mesenchymal cells referred to as lung spheroids. [128,129] These lung spheroids were derived similar to hPSC-derived intestinal organoids that relied on growth factor stimulated self-assembly to induce spheroid formation from the endodermal monolayer.…”

GRHL2 coordinates regeneration of a polarized mucociliary epithelium from basal stem cells

“…Specifically, recent studies have implicated Notch3 in promoting the differentiation of adult basal stem cells into parabasal progenitors and Notch1 and 2 in fate selection between secretory and ciliated linages (Rock et al, 2011b;Danahay et al, 2015;Mori et al, 2015;Pardo-Saganta et al, 2015). ChIP-Seq has shown Grhl2 occupancy of binding sites near NOT CH1, NOT CH3, JAG1, and JAG2 (Gao et al, 2013).…”

Dissecting the stem cell niche with organoid models: an engineering-based approach

“…Recent studies have used these features to identify juxtacrine and secreted factors that direct airway epithelial cell fate in mouse tracheosphere and human bronchosphere organoids (Danahay et al, 2015;Rock et al, 2011;Tadokoro et al, 2014) expressing a Notch activity reporter, Rock and colleagues analyzed Notch activity in developing 2-to 16-cell mouse tracheospheres following initial stem cell division. They observed that single basal stem cells that express the Notch ligands Jagged and Delta divide either symmetrically to produce two basal daughter cells or asymmetrically to produce one basal daughter cell and one luminal daughter cell in which Notch signaling is active.…”