decellularized lung extracellular matrix scaffold promotes human embryonic stem cell differentiation towards alveolar progenitors

Objective: efficient production of functional and mature alveolar epithelial is a major challenge for developing any cellreplacement therapy for lung degenerative diseases. the extracellular matrix (ecm) pro-vides a dynamic environmentand mediates cellular responses during development and maintenance of tissue functions. the decellularized ecm(decm) which retains its native-like structure and bio-chemical composition can provide the induction of embryonicstem cell (esc) differentiation toward the tissue-specific lineages during in vitro culture. therefore, the aim of this studywas to evaluate the effect of sheep lung decm-derived scaffold on differentiation and further maturation of esc-derivedlung progenitor cells.materials and methods: this study was an experimental study. in the first step, a sheep lung was decellularizedto achieve decm scaffolds and hydrogels. afterwards, the obtained decm scaffold was evaluated for collagen andglycosaminoglycan contents, dna quantification, and its ultrastructure. next, the three experimental groups: i. sheeplung decm-derived scaffold, ii. sheep lung decm-derived hydrogel, and iii. fibronectin-coated plates were comparedin their abilities to induce further differentiation of human embryonic stem cells (hescs)-derived definitive endoderm(de) into lung progenitor cells. the comparison was evaluated by immuno-staining and real-time polymerase chainreaction (pcr) assessments.results: we found that the decm-derived scaffold preserved its composition and native porous structures whilelacking nuclei and intact cells. all experimental groups displayed lung progenitor cell differen-tiation as revealed by therna and protein expression of nkx2.1, p63 and ck5. de cells differenti-ated on decm-derived scaffold and decmderivedhydrogel showed significant upregulation of sox9 gene expression, a marker of the distal airway epithelium.de cells differentiated on the decm-derived scaffold compared to the two other groups, showed enhanced expressionof sftpc (type 2 alveolar epithelial [at2] cell marker), foxj1 (ciliated cell marker), and muc5a (secretory cell marker)genes.conclusion: overall, our results suggest that decm-derived scaffold improves the differentiation of de cells towardslung alveolar progenitor cells in comparison with decm-derived hydrogel and fibronectin-coated plates.