High contrast microstructural visualization of natural acellular matrices by means of phase-based x-ray tomography

Abstract

Acellular scaffolds obtained via decellularization are a key instrument in regenerative medicine both per se and to drive the development of future-generation synthetic scaffolds that could become available off-the-shelf. In this framework, imaging is key to the understanding of the scaffolds’ internal structure as well as their interaction with cells and other organs, including ideally post-implantation. Scaffolds of a wide range of intricate organs (esophagus, lung, liver and small intestine) were imaged with x-ray phase contrast computed tomography (PC-CT). Image quality was sufficiently high to visualize scaffold microarchitecture and to detect major anatomical features, such as the esophageal mucosal-submucosal separation, pulmonary alveoli and intestinal villi. These results are a long-sought step for the field of regenerative medicine; until now, histology and scanning electron microscopy have been the gold standard to study the scaffold structure. However, they are both destructive: hence, they are not suitable for imaging scaffolds prior to transplantation, and have no prospect for post-transplantation use. PC-CT, on the other hand, is non-destructive, 3D and fully quantitative. Importantly, not only do we demonstrate achievement of high image quality at two different synchrotron facilities, but also with commercial x-ray equipment, which makes the method available to any research laboratory.

Multimodal Phase-Based X-Ray Microtomography with Nonmicrofocal Laboratory Sources

“…The results in Fig. 3 show how the phase signal and its sensitivity are not negatively affected by the presence of a strong USAXS signal, and the results obtained from the esophagus scaffold confirm the possibility of using laboratory phase-contrast CT in tissue engineering and regenerative medicine, as has already been proposed by Hagen et al [32].…”

“…70/2719). This sample was previously imaged at a synchrotron and in the laboratory using different phase-contrast imaging techniques [32] (free-space propagation at the synchrotron and edge illumination in the laboratory).…”

“…A complete description of the sample preparation and the results obtained can be found in Ref. [32]. The signals reconstructed from the esophagus are shown in Fig.…”

Monochromatic Propagation-Based Phase-Contrast Microscale Computed-Tomography System with a Rotating-Anode Source

“…The first sample is an oesophageal acellular matrix (ACM), derived from a piglet, provided by the Institute of Child Health (ICH). The ACM is derived via an established decelluarization technique called detergent enzymatic treatment (DET) [34,35]. Following the DET, the sample is critical-point dried using CO 2 .…”

Evaluation of phase retrieval approaches in magnified X-ray phase nano computerized tomography applied to bone tissue

“…Phase contrast can be obtained experimentally by various techniques either on synchrotron radiation or laboratory sources (for a review see [8,9]). Here, we will focus on propagation-based phase contrast imaging [10] as it provides the highest spatial resolution.…”