Herbsttagung Programm & Abstracts - Deutsche Gesellschaft für ...

Characterization of bronchioalveolar stem cells and the embryonic stem cell
marker Oct-4 in adult mouse lung.
C. Koumba 1 ; I. Salwig 1 ; M. Szibor 1 ; H.R. Schöler 3 ; W. Seeger 1,2 ; R. Voswinckel 1,2
1
Max-PIanck-Institute for Heart and lung research, Bad Nauheim; 2 Departement of Internal Medicine,
University Hospital Giessen; 3 MPI for Molecular Biomedecine, Münster, Germany
Objective: The evidence that bronchioalveolar stem cells (BASCs) serve as a real stem cell type for
the distal lung has been challenged recently. It is currently unclear what their function is and how their
pool and progeny is regulated during lung regeneration and repair. We aim to identify and characterize
BASCs in adult mouse lung and to describe the embryonic stem cell marker Oct-4 and its possible role
in adult distal lung stem cells by improved methods.
Results: We identified by immunohistochemistry the proposed BASC cell population coexpressing
SP-C, a marker for alveolar type 2 cells, and CCSP, a marker for bronchial epithelial clara cells, that
resides at the bronchioalveolar duct junction (BADJ). BASCs were then identified by flow cytometry
based on an adjusted McQualter protocol for their expression of EpCAM and CD24 and the absence
of CD31 and CD45. Also, lung mesenchymal stromal cells that have EpCAM(-)/Sca-1(+) phenotype
required for the differentiation of BASCs were isolated. Oct-4 was also identified in adult mouse lung
by immunohistochemistry.
Conclusion/Outlook: We further aim to establish in vitro colony formation assays and in vivo
differentiation assays for alveolar stem cells to address changes in stemness and proliferative activity
during experimental lung diseases and lung regeneration.
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