Bone Marrow-Derived VSELs Engraft as Lung Epithelial Progenitor Cells after Bleomycin-Induced Lung Injury.

Andrzej K Ciechanowicz,Diane S Krause,Katarzyna Sielatycka,Marta Skoda,Malwina Suszyńska,Magdalena Kucia,Monika Cymer,Mariusz Z Ratajczak,Kamila Bujko

doi:10.3390/cells10071570

Abstract

Background: Alveolar type 2 (AT2) cells and bronchioalveolar stem cells (BASC) perform critical regenerative functions in response to lung damage. Published data show that nonhematopoietic, bone marrow-derived “very small embryonic-like stem cells” (VSELs) can differentiate in vivo into surfactant protein C (SPC)-producing AT2 cells in the lung. Here, we test directly whether VSEL-derived BASC and AT2 cells function to produce differentiated progeny. Methods: using a reporter mouse in which the H2B-GFP fusion protein is driven from the murine SPC promoter, we tested whether bone marrow-derived VSELs or non-VSEL/nonhematopoietic stem cells (non-VSEL/non-HSCs) can differentiate into AT2 and BASC cells that function as progenitor cells. Immediately following bleomycin administration, WT recipient mice underwent intravenous administration of VSELs or non-VSEL/non-HSCs from SPC H2B-GFP mice. GFP+ AT2 and BASC were isolated and tested for progenitor activity using in vitro organoid assays. Results: after 21 days in vivo, we observed differentiation of VSELs but not non-VSEL/non-HSCs into phenotypic AT2 and BASC consistent with previous data in irradiated recipients. Subsequent in vitro organoid assays revealed that VSEL-derived AT2 and BASC maintained physiological potential for differentiation and self-renewal. Conclusion: these findings prove that VSELs produce functional BASC and AT2 cells, and this may open new avenues using VSELs to develop effective cell therapy approaches for patients with lung injury.

Highlights

We tested different cell populations postbleomycin administration for their ability to differentiate into functional epithelial cells of the lung, Alveolar type 2 (AT2) cells and bronchioalveolar stem cells (BASC)
The aim of our study was to determine whether bone-marrow-derived VSELs transplanted into mice after lung injury can differentiate into lung epithelial cells that can serve as functional progenitors
We demonstrate the engraftment of VSELderived lung epithelial progenitors in a mouse model with bleomycin-induced lung injury

Summary

Introduction

Regional epithelial stem/progenitor cell populations maintain and regenerate lung tissue in normal physiological and damage repair states. Alveolar type 2 (AT2) cells and bronchioalveolar stem cells (BASC) perform critical regenerative functions in response to lung damage. Published data show that nonhematopoietic, bone marrow-derived “very small embryonic-like stem cells” (VSELs) can differentiate in vivo into surfactant protein C (SPC)-producing AT2 cells in the lung. We test directly whether VSELderived BASC and AT2 cells function to produce differentiated progeny. Methods: using a reporter mouse in which the H2B-GFP fusion protein is driven from the murine SPC promoter, we tested whether bone marrow-derived VSELs or non-VSEL/nonhematopoietic stem cells (non-VSEL/nonHSCs) can differentiate into AT2 and BASC cells that function as progenitor cells. Following bleomycin administration, WT recipient mice underwent intravenous administration of VSELs or non-VSEL/non-HSCs from SPC H2B-GFP mice. Conclusion: these findings prove that VSELs produce functional BASC and AT2 cells, and this may open new avenues using VSELs to develop effective cell therapy approaches for patients with lung injury

Objectives

Methods

Results

Conclusion