Abstract
Bioartificial lungs re-engineered from decellularized organ scaffolds are a promising alternative to lung transplantation. Critical features for improving scaffold repopulation depend on the mechanical properties of the cell microenvironment. However, the mechanics of the lung extracellular matrix (ECM) is poorly defined. The local mechanical properties of the ECM were measured in different regions of decellularized rat lung scaffolds with atomic force microscopy. Lungs excised from rats (n = 11) were decellularized with sodium dodecyl sulfate (SDS) and cut into ∼7 μm thick slices. The complex elastic modulus (GL) of lung ECM was measured over a frequency band ranging from 0.1 to 11.45 Hz. Measurements were taken in alveolar wall segments, alveolar wall junctions and pleural regions. The storage modulus (G′, real part of GL) of alveolar ECM was ∼6 kPa, showing small changes between wall segments and junctions. Pleural regions were threefold stiffer than alveolar walls. G′ of alveolar walls and pleura increased with frequency as a weak power law with exponent 0.05. The loss modulus (G″, imaginary part of GL) was 10-fold lower and showed a frequency dependence similar to that of G′ at low frequencies (0.1-1 Hz), but increased more markedly at higher frequencies. Local differences in mechanical properties and topology of the parenchymal site could be relevant mechanical cues for regulating the spatial distribution, differentiation and function of lung cells.
Original language | English (US) |
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Pages (from-to) | 6852-6859 |
Number of pages | 8 |
Journal | Acta Biomaterialia |
Volume | 9 |
Issue number | 6 |
DOIs | |
State | Published - Jun 2013 |
Keywords
- Alveolar mechanics
- Atomic force microscopy
- Bioengineered lungs
- Biological scaffolds
- Extracellular matrix mechanics
ASJC Scopus subject areas
- Biotechnology
- Biomaterials
- Biochemistry
- Biomedical Engineering
- Molecular Biology