Search bioRxiv⌕ Search

Biology subjects

Schneider-Daum, N.

Publications and source records attributed to Schneider-Daum, N..

2 recordsLinked to original sources

Mutual regulation of transcriptomes between pneumocytes and fibroblasts mediates alveolar regeneration

Alveolar type 2 (AT2) and club cells are part of the stem cell niche of the lung and their differentiation is required for pulmonary homeostasis and tissue regeneration. A disturbed crosstalk between fibroblasts and epithelial cells contributes to the loss of lung structure in chronic lung diseases. Therefore, it is important to understand how fibroblasts and lung epithelial cells interact during regeneration. Here we analyzed the interaction of fibroblasts and the alveolar epithelium modelled in air-liquid interface cultures. Single-cell transcriptomics showed that co-cultivation with fibroblasts leads to increased expression of type 2 markers in pneumocytes, activation of regulons associated with maintenance of alveolar type 2 cells, and trans-differentiation of club cells towards pneumocytes. This was accompanied by an intensified transepithelial barrier. Vice versa, activation of NF{kappa}B pathways and the CEBPB regulon as well as the expression of IL-6 and other differentiation factors (e.g. FGFs) were increased in fibroblasts co-cultured with epithelial cells. Recombinant IL-6 enhanced epithelial barrier formation. Therefore, in our co-culture model, regulatory loops were identified by which lung epithelial cells mediate regeneration and differentiation of the alveolar epithelium in a cooperative manner with the mesenchymal compartment.

cell biology↗

Second-generation lung-on-a-chip array with a stretchable biological membrane

The complex architecture of the lung parenchyma and the air-blood barrier is difficult to mimic in-vitro. Recently reported lung-on-a-chips used a thin, porous and stretchable PDMS membrane, to mimic the air-blood barrier and the rhythmic breathing motions. However, the nature, the properties and the size of this PDMS membrane differ from the extracellular matrix of the distal airways. Here, we present a second-generation lung-on-a-chip with an array of in vivo-like sized alveoli and a stretchable biological membrane. This nearly absorption free membrane allows mimicking in vivo functionality of the lung parenchyma at an unprecedented level. The air-blood barrier is constituted by human primary lung alveolar epithelial cells from several patients and co-cultured with primary lung endothelial cells. Typical markers of lung alveolar epithelial cells could be observed in the model, while barrier properties were preserved for up to three weeks. This advanced lung alveolar model reproduces some key features of the lung alveolar environment in terms of composition, alveolar size, mechanical forces and biological functions, which makes this model a more analogous tool for drug discovery, diseases modeling and precision medicine applications.

bioengineering↗