Effect of Pressure Conditions in Uterine Decellularization Using Hydrostatic Pressure on Structural Protein Preservation

Decellularized Extracellular Matrix Scaffolds: Recent Advances and Emerging Strategies in Bone Tissue Engineering

Bone tissue engineering (BTE) is a complex biological process involving the repair of bone tissue with proper neuronal network and vasculature as well as bone surrounding soft tissue. Synthetic biomaterials used for BTE should be biocompatible, support bone tissue regeneration, and eventually be degraded in situ and replaced with the newly generated bone tissue. Recently, various forms of bone graft materials such as hydrogel, nanofiber scaffolds, and 3D printed composite scaffolds have been developed for BTE application. Decellularized extracellular matrix (DECM), a kind of natural biological material obtained from specific tissues and organs, has certain advantages over synthetic and exogenous biomaterial-derived bone grafts. Moreover, DECM can be developed from a wide range of biological sources and possesses strong molding abilities, natural 3D structures, and bioactive factors. Although DECM has shown robust osteogenic, proangiogenic, immunomodulatory, and bone defect healing potential, the rapid degradation and limited mechanical properties should be improved for bench-to-bed translation in BTE. This review summarizes the recent advances in DECM-based BTE and discusses emerging strategies of DECM-based BTE.

Toward human uterus tissue engineering: Uterine decellularization in a non-human primate species

INTRODUCTION

Uterus bioengineering offers a potential treatment option for women with uterine factor infertility and for mitigating the risk of uterine rupture associated with women with defective uterine tissue. Decellularized uterine tissue scaffolds proved promising in further in vivo experiments in rodent and domestic species animal models. Variations in the extracellular matrix composition among different species and adaptations of the decellularization protocols make it difficult to compare the results between studies. Therefore, we assessed if our earlier developed sodium deoxycholate-based decellularization protocol for the sheep and the cow uterus could become a standardized cross-species protocol by assessing it on the non-human primate (baboon) uterus.

MATERIAL AND METHODS

The baboon uterus was decellularized using sodium deoxycholate, and the remaining acellular scaffold was quantitatively assessed for DNA, protein, and specific extracellular matrix components. Furthermore, electron microscopy deepened morphology examination, while the chorioallantoic membrane assay examined the scaffolds' cytotoxicity, bioactivity, and angiogenic properties. The in vitro recellularization efficiency of the scaffolds using xenogeneic (rat) bone marrow-derived mesenchymal stem cells was also assessed. Finally, the immune potential of the scaffolds was evaluated by in vitro exposure to human peripheral blood mononuclear cells.

RESULTS

We obtained a decellularized baboon uterus with preserved extracellular matrix components by adding an 8-h sodium deoxycholate perfusion to our previously developed protocol for the sheep and cow models. This minor modification resulted in scaffolds with less than 1% of immunogenic host DNA content while preserving important uterine-specific collagen, elastin, and glycosaminoglycan structures. The chorioallantoic membrane assay and in vitro recellularization experiments confirmed that the scaffolds were bioactive and non-cytotoxic. As we have observed in other animal models, the enzymatic scaffold preconditioning with matrix metalloproteinases improved the recellularization efficiency further. Additionally, the preconditioning generated more immune-privileged scaffolds, as shown in a novel in vitro co-culture assay with human peripheral blood mononuclear cells.

CONCLUSIONS

For the first time, our data demonstrate the efficiency of our protocol for non-human primate uteri and its translational potential. This standardized protocol will facilitate cross-study comparisons and expedite clinical translation.

Comparative analysis of porcine-uterine decellularization for bioactive-molecule preservation and DNA removal

Introduction

Decellularized uterine extracellular matrix has emerged as a pivotal focus in the realm of biomaterials, offering a promising source in uterine tissue regeneration, research on disease diagnosis and treatments, and ultimately uterine transplantation. In this study, we examined various protocols for decellularizing porcine uterine tissues, aimed to unravel the intricate dynamics of DNA removal, bioactive molecules preservation, and microstructural alterations.

Methods

Porcine uterine tissues were treated with 6 different, yet rigorously selected and designed, protocols with sodium dodecyl sulfate (SDS), Triton® X-100, peracetic acid + ethanol, and DNase I. After decellularization, we examined DNA quantification, histological staining (H&E and DAPI), glycosaminoglycans (GAG) assay, scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and Thermogravimetric Analysis (TGA).

Results

A comparative analysis among all 6 protocols was conducted with the results demonstrating that all protocols achieved decellularization; while 0.1% SDS + 1% Triton® X-100, coupled with agitation, demonstrated the highest efficiency in DNA removal. Also, it was found that DNase I played a key role in enhancing the efficiency of the decellularization process by underscoring its significance in digesting cellular contents and eliminating cell debris by 99.79% (19.63 ± 3.92 ng/mg dry weight).

Conclusions

Our findings enhance the nuanced understanding of DNA removal, GAG preservation, microstructural alteration, and protein decomposition in decellularized uterine extracellular matrix, while highlighting the importance of decellularization protocols designed for intended applications. This study along with our findings represents meaningful progress for advancing the field of uterine transplantation and related tissue engineering/regenerative medicine.

Cardiac tissue engineering: an emerging approach to the treatment of heart failure

Heart failure is a major health problem in which the heart is unable to pump enough blood to meet the body's needs. It is a progressive disease that becomes more severe over time and can be caused by a variety of factors, including heart attack, cardiomyopathy and heart valve disease. There are various methods to cure this disease, which has many complications and risks. The advancement of knowledge and technology has proposed new methods for many diseases. One of the promising new treatments for heart failure is tissue engineering. Tissue engineering is a field of research that aims to create living tissues and organs to replace damaged or diseased tissue. The goal of tissue engineering in heart failure is to improve cardiac function and reduce the need for heart transplantation. This can be done using the three important principles of cells, biomaterials and signals to improve function or replace heart tissue. The techniques for using cells and biomaterials such as electrospinning, hydrogel synthesis, decellularization, etc. are diverse. Treating heart failure through tissue engineering is still under development and research, but it is hoped that there will be no transplants or invasive surgeries in the near future. In this study, based on the most important research in recent years, we will examine the power of tissue engineering in the treatment of heart failure.

Extracellular matrix-derived materials for tissue engineering and regenerative medicine: A journey from isolation to characterization and application

Biomaterial choice is an essential step during the development tissue engineering and regenerative medicine (TERM) applications. The selected biomaterial must present properties allowing the physiological-like recapitulation of several processes that lead to the reestablishment of homeostatic tissue or organ function. Biomaterials derived from the extracellular matrix (ECM) present many such properties and their use in the field has been steadily increasing. Considering this growing importance, it becomes imperative to provide a comprehensive overview of ECM biomaterials, encompassing their sourcing, processing, and integration into TERM applications. This review compiles the main strategies used to isolate and process ECM-derived biomaterials as well as different techniques used for its characterization, namely biochemical and chemical, physical, morphological, and biological. Lastly, some of their applications in the TERM field are explored and discussed.