Journal of Tissue Engineering and Regenerative Medicine最新文献

RETRACTION: O. Karaman, A. Kumar, S. Moeinzadeh, X. He, T. Cui, and E. Jabbari, “Effect of Surface Modification of Nanofibres with Glutamic Acid Peptide on Calcium Phosphate Nucleation and Osteogenic Differentiation of Marrow Stromal Cells,” Journal of Tissue Engineering and Regenerative Medicine 10, no. 2 (2016): E132–E146, https://doi.org/10.1002/term.1775.

The above article, published online on 30 July 2013 in Wiley Online Library (https://wileyonlinelibrary.com), has been retracted by John Wiley & Sons, Ltd, following concerns raised by a third party. An investigation identified several instances of duplication of elements within Figures 5 and 8. The authors cooperated with the investigation; however, due to the time elapsed since publication, they were unable to provide the original raw data. While some supporting data were provided, this was not sufficient to restore confidence in the article’s results and conclusions. Therefore, the publisher considers this article unreliable. The authors disagree with the retraction.

RETRACTION: O. Karaman, A. Kumar, S. Moeinzadeh, X. He, T. Cui, and E. Jabbari, “Effect of Surface Modification of Nanofibres with Glutamic Acid Peptide on Calcium Phosphate Nucleation and Osteogenic Differentiation of Marrow Stromal Cells,” Journal of Tissue Engineering and Regenerative Medicine 10, no. 2 (2016): E132–E146, https://doi.org/10.1002/term.1775.

The above article, published online on 30 July 2013 in Wiley Online Library (https://wileyonlinelibrary.com), has been retracted by John Wiley & Sons, Ltd, following concerns raised by a third party. An investigation identified several instances of duplication of elements within Figures 5 and 8. The authors cooperated with the investigation; however, due to the time elapsed since publication, they were unable to provide the original raw data. While some supporting data were provided, this was not sufficient to restore confidence in the article’s results and conclusions. Therefore, the publisher considers this article unreliable. The authors disagree with the retraction.

Providing a functional pericellular matrix (PCM) by fine-tuning the microenvironment of the articular chondrocytes (ACs) can greatly improve the outcomes of articular cartilage tissue engineering. While harvesting ACs with their PCM (chondrons) results in a low cell yield and a heterogeneous mixture of ACs and chondrons, microscale hydrogels could be used for mechanical tuning of the cell microenvironment. This may enable the use of stiffer bulk materials, improving the load-bearing capacity of the construct. This study investigates the effect of microenvironmental stiffness, independent of total construct stiffness, on the regenerative performance of ACs (ECM and PCM synthesis). Additionally, we explored articular cartilage–derived progenitor cells (ACPCs) as a possible alternative to ACs in the presented system. ACs were cultured in a soft or stiff bulk hydrogel (GelMA) or were encapsulated in soft microgels and seeded into the stiff GelMA. Constructs were seeded in an ex vivo porcine chondral defect model and cultured for 28 days with dynamic mechanical stimulation using a compression-sliding bioreactor. PCM and ECM quality were assessed through cell content analysis, immunofluorescent staining, histology, and measurements of GAG and collagen content. Cell encapsulation influenced ECM synthesis and PCM amount and completeness throughout the construct. Although the nonencapsulated groups showed stronger overall alcian blue staining, the encapsulated groups demonstrated more uniform matrix deposition throughout the depth of the tissue. Furthermore, ACPCs performed similarly to ACs. These findings suggest that the approach to differentially tune encapsulating and bulk hydrogel properties holds potential for future articular cartilage tissue engineering, and that ACPCs could be used as an alternative cell source.

Providing a functional pericellular matrix (PCM) by fine-tuning the microenvironment of the articular chondrocytes (ACs) can greatly improve the outcomes of articular cartilage tissue engineering. While harvesting ACs with their PCM (chondrons) results in a low cell yield and a heterogeneous mixture of ACs and chondrons, microscale hydrogels could be used for mechanical tuning of the cell microenvironment. This may enable the use of stiffer bulk materials, improving the load-bearing capacity of the construct. This study investigates the effect of microenvironmental stiffness, independent of total construct stiffness, on the regenerative performance of ACs (ECM and PCM synthesis). Additionally, we explored articular cartilage–derived progenitor cells (ACPCs) as a possible alternative to ACs in the presented system. ACs were cultured in a soft or stiff bulk hydrogel (GelMA) or were encapsulated in soft microgels and seeded into the stiff GelMA. Constructs were seeded in an ex vivo porcine chondral defect model and cultured for 28 days with dynamic mechanical stimulation using a compression-sliding bioreactor. PCM and ECM quality were assessed through cell content analysis, immunofluorescent staining, histology, and measurements of GAG and collagen content. Cell encapsulation influenced ECM synthesis and PCM amount and completeness throughout the construct. Although the nonencapsulated groups showed stronger overall alcian blue staining, the encapsulated groups demonstrated more uniform matrix deposition throughout the depth of the tissue. Furthermore, ACPCs performed similarly to ACs. These findings suggest that the approach to differentially tune encapsulating and bulk hydrogel properties holds potential for future articular cartilage tissue engineering, and that ACPCs could be used as an alternative cell source.

Fibrosis and angiogenesis are key contributors to synovial inflammation in both the early and progressive stages of rheumatoid arthritis (RA) and osteoarthritis (OA), making them important therapeutic targets to mitigate joint tissue damage. In vitro drug screening, particularly for antifibrotic and antiangiogenic efficacy, is a standard method for evaluating therapeutic candidates prior to in vivo testing. Traditionally, most studies have relied on two-dimensional (2D) monolayer cell cultures, which lack physiologically relevant cell-matrix and cell-cell interactions. Substantial evidence now indicates that three-dimensional (3D) culture systems more accurately recapitulate the structural and functional complexity of native tissue environments. We employed 3D spheroid culture models of fibrosis and neovascularization to evaluate the antiangiogenic and antifibrotic effects of pirfenidone (PFD), an FDA-approved drug for idiopathic pulmonary fibrosis. Spheroid monocultures of 3T3 fibroblasts and co-cultures of human umbilical vein endothelial cells (HUVECs) and human aortic smooth muscle cells (SMCs) were encapsulated in cell-adhesive, proteolytically degradable polyethylene glycol (PEG) hydrogel scaffolds. The temporal effects of PFD dose and timing of addition in culture on fibroblast outgrowth, vascular sprouting, and viability were quantified up to 14 days. PFD treatment led to dose-dependent inhibition of both fibroblast outgrowth and vascular sprouting, depending on the initial timing of PFD addition, with cell viability maintained under all conditions. In addition, PFD reversed the onset of fibrosis and neovascularization. PFD exhibited antifibrotic activity and antiangiogenic potential in 3D cultures.

Meniscal injuries present a significant clinical challenge due to the limited self-healing capacity of avascular regions and the unsatisfactory long-term outcomes of current repair strategies. Collagen, the primary structural component of the meniscal extracellular matrix (ECM), plays a crucial role in maintaining its biomechanical integrity and guiding tissue regeneration. This review summarizes recent advances in collagen scaffolds technology, focusing on materials, collagen extraction, and scaffold fabrication methods, as well as their in vivo interactions with cells that regulate tissue regeneration. The mechanical enhancement of collagen scaffolds through crosslinking and reinforcement with synthetic polymers is discussed, alongside strategies for controlled degradation and biological integration. Despite remaining challenges in mechanical durability and long-term stability, these developments position collagen-based scaffolds as a promising avenue toward clinically viable meniscal repair solutions.

Decellularized articular cartilage of human origin presents itself as the most homologous filling material for focal cartilage defects. Yet, the full repopulation of the exceptionally dense collagen construct has never been achieved without providing host cells with artificially created migration paths into the matrix. Within this study, we examine the use of a femtosecond laser to engrave fine patterns into human articular cartilage before decellularization and GAG depletion (decell-deGAG). Scaffolds were tested for decellularization success and mechanical behavior. Seeding tests were performed to assess biocompatibility and examine the performance in a simulated defect environment using an osteochondral plug model in vitro and in vivo in an ectopic nude mouse model. The composition and structure of the newly formed repair tissue and macrophage recruitment were observed via histology. The femtosecond laser was successful in engraving deep, fine structures into the matrix without the thermal damage found with other laser techniques. Engraving was also beneficial for decellularization success. The resulting decell-deGAG scaffold featured a compressive modulus many times stronger than other biomaterials commonly used for cartilage regeneration and presents a defect filling material that is similar to the tissue it is meant to replace. Moreover, the incisions promoted the repopulation with therapeutically relevant cells. A favorable spatial environment inside the incisions facilitated the formation of repair tissue that mimics hyaline cartilage in composition and collagen orientation. Scaffolds were well-integrated within simulated defects. Femtosecond laser–engraved cartilage poses an authentic defect filling material with cartilage-like properties. When used in combination with cell seeding, it promotes the formation of differentiated repair tissue. Thus, the hereby presented biomaterial shows great potential in improving the repair of focal cartilage defects and reducing long-term graft failures.