Tissue Engineering Part A最新文献

{"title":"<i>In Situ</i> Bioprinting Embryonic-Derived Stem Cells to Repair Human <i>Ex Vivo</i> Chondral Defects.","authors":"Shawn P Grogan, Erik W Dorthé, Nicholas E Glembotski, Darryl D D'Lima","doi":"10.1089/ten.tea.2024.0346","DOIUrl":"https://doi.org/10.1089/ten.tea.2024.0346","url":null,"abstract":"<p><p>Successful bioprinting requires an appropriate combination of bioinks, cells, and a delivery platform. To demonstrate the potential of <i>in situ</i> bioprinting for regeneration of cartilage lesions we combined clinically relevant embryonic-derived mesenchymal stem cells (ES-MSCs) with a fibrin-based bioink that was delivered into chondral defects created in human <i>ex vivo</i> osteoarthritic (OA) tissue using a bioprinting platform. We used an integrated multitool, 6-axis bioprinting system to laser scan and map the surface of chondral defects and bioprint within the cartilage defects <i>in vitro</i> and <i>ex vivo</i>. For cartilage neotissue generation, clinically relevant ES-MSCs were encapsulated at 20 × 10⁶ cells per mL in chondro-inductive bioinks composed of fibrinogen mixed with nanocellulose or fibrinogen mixed with nanocellulose and hyaluronic acid. After bioprinting as free-standing constructs or <i>in situ</i> within chondral defects, gels were cross-linked in thrombin and cultured for up to 8 weeks in chondrogenic medium. Print fidelity was assessed in the free-standing printed constructs after cross-linking and culture. <i>In situ</i> bioprinted constructs were evaluated for cell viability, mechanical properties, histology (Safranin O and collagen type II immunostaining), and gene expression of chondrogenic genes. Adding nanocellulose to fibrinogen significantly improved print fidelity. ES-MSCs in the fibrinogen-based bioink formulations generated cartilage-like neotissues with positive Safranin O and collagen type II staining. Chondrogenic genes (COLA2A1, ACAN, COMP, and SOX9) were significantly upregulated with negligible expression of hypertrophic markers (COL10A1 and RUNX2). The mechanical properties of the printed constructs increased from 30 to 50 kPa after 3 weeks to ∼150 kPa after 8 weeks in culture. We demonstrated the feasibility of combining clinically relevant ES-MSCs with printable fibrin-based hydrogel bioinks and an integrated bioprinting platform for <i>in situ</i> bioprinting that promoted neocartilage tissue generation and repair of <i>ex vivo</i> lesions in human OA tissues.</p>","PeriodicalId":56375,"journal":{"name":"Tissue Engineering Part A","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144021314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Glycations on Decellularized Muscle Matrix Reduce Muscle Regeneration and Increase Inflammation.","authors":"Lucas C Olson, Ammar Y Jawad, Eirian S Crocker, Scott E Pennebaker, Brock P Lodato, David J Cohen, Zvi Schwartz, Michael J McClure","doi":"10.1089/ten.tea.2024.0284","DOIUrl":"https://doi.org/10.1089/ten.tea.2024.0284","url":null,"abstract":"<p><p>Volumetric muscle loss (VML) due to traumatic injury results in the abrupt loss of contractile units, stem cells, and connective tissue, leading to long-term muscle dysfunction and reduced regenerative potential. Muscle connective tissue contains a proregenerative extracellular matrix (ECM), and our lab harnesses the regenerative capacity of decellularized muscle matrix (DMM) to treat VML, a condition with limited treatment options. However, a major limitation is that muscle often comes from aged donors. Previous work from our lab showed that aged donor muscle contains higher levels of advanced glycation end-product (AGE) cross-links compared to muscle from younger donors. This study aimed to determine whether increased AGE cross-links reduce the regenerative capacity of DMM. To test this, we first generated AGEs in DMM with direct D-ribose incubation. We then removed ∼35% of the gastrocnemius muscle in a model and treated it with either AGE-DMM or standard DMM (no AGEs), comparing results to controls. Although muscle force results remained unchanged between AGE-DMM and DMM, AGEs led to reduced muscle mass in histological sections, fewer fibers, and smaller fiber diameters. AGEs also increased collagen levels in histology, but protein assays showed reduced collagen production. We investigated the canonical receptor for AGEs, the receptor for AGEs (RAGE), and found elevated levels in AGE-treated VML compared to DMM alone, along with increased levels of the noncanonical receptor galectin-3. Both RAGE and galectin-3 are associated with inflammation, and proteomics revealed higher inflammatory markers in AGE-treated muscle than in DMM alone. In conclusion, our data suggest that AGEs impair the regenerative potential of DMM, highlighting the importance of considering donor age when sourcing muscle for DMM therapies. Impact Statement This study investigates advanced glycation end-product cross-links in skeletal muscle extracellular matrix (ECM) as a way to model its deleterious effects on muscle regeneration <i>in vivo</i>. We demonstrate here that ECM glycations reduce muscle regeneration, enhance inflammatory markers, reduce ECM protein production, and proteomic analysis identified unique targets that could be explored in future research endeavors.</p>","PeriodicalId":56375,"journal":{"name":"Tissue Engineering Part A","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143993368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Infection Model for SARS-CoV-2 Using Rat Transplanted with hiPSC-Airway Epithelial Cells.","authors":"Masayuki Kitano, Hiroe Ohnishi, Akiko Makino, Tatsuo Miyamoto, Yasuyuki Hayashi, Keisuke Mizuno, Shinji Kaba, Yoshitaka Kawai, Tsuyoshi Kojima, Yo Kishimoto, Norio Yamamoto, Keizo Tomonaga, Koichi Omori","doi":"10.1089/ten.TEA.2024.0016","DOIUrl":"10.1089/ten.TEA.2024.0016","url":null,"abstract":"<p><p>Investigating the infection mechanism of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the airway epithelium and developing effective defense strategies against infection are important. To achieve this, establishing appropriate infection models is crucial. Therefore, various <i>in vitro</i> models, such as cell lines and primary cultures, and <i>in vivo</i> models involving animals that exhibit SARS-CoV-2 infection and genetically humanized animals have been used as animal models. However, no animal model has been established that allows infection experiments with human cells under the physiological environment of airway epithelia. Therefore, we aimed to establish a novel animal model that enables infection experiments using human cells. Human induced pluripotent stem cell-derived airway epithelial cell-transplanted nude rats (hiPSC-AEC rats) were used, and infection studies were performed by spraying lentiviral pseudoviruses containing SARS-CoV-2 spike protein and the <i>GFP</i> gene on the tracheae. After infection, immunohistochemical analyses revealed the existence of GFP-positive-infected transplanted cells in the epithelial and submucosal layers. In this study, a SARS-CoV-2 infection animal model including human cells was established mimicking infection through respiration, and we demonstrated that the hiPSC-AEC rat could be used as an animal model for basic research and the development of therapeutic methods for human-specific respiratory infectious diseases.</p>","PeriodicalId":56375,"journal":{"name":"Tissue Engineering Part A","volume":" ","pages":"361-372"},"PeriodicalIF":3.5,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141238790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rat Tracheal Cartilage Regeneration Using Mesenchymal Stem Cells Derived From Human iPS Cells.","authors":"Keisuke Mizuno, Hiroe Ohnishi, Yo Kishimoto, Tsuyoshi Kojima, Shintaro Fujimura, Yoshitaka Kawai, Masayuki Kitano, Makoto Ikeya, Koichi Omori","doi":"10.1089/ten.TEA.2024.0151","DOIUrl":"10.1089/ten.TEA.2024.0151","url":null,"abstract":"<p><p>Tracheal cartilage provides structural support to the airways to enable breathing. However, it can become damaged or impaired, sometimes requiring surgical resection and reconstruction. Previously, we clinically applied an artificial trachea composed of a polypropylene mesh and collagen sponge, with a favorable postoperative course. However, the artificial trachea presents a limitation, as the mesh is not biodegradable and cannot be used in pediatric patients. Compared to a polypropylene mesh, regenerated cartilage represents an ideal material for reconstruction of the damaged trachea. The use of mesenchymal stem cells (MSCs) as a source for cartilage regeneration has gained widespread acceptance, but challenges such as the invasiveness of harvesting and limited cell supply persist. Therefore, we focused on the potential of human-induced pluripotent stem cell (hiPSC)-derived mesenchymal stem cells (iMSCs) for tracheal cartilage regeneration. In this study, we aimed to regenerate tracheal cartilage on an artificial trachea as a preliminary step to replace the polypropylene mesh. iMSCs were induced from hiPSCs through neural crest cells and transplanted with a polypropylene mesh covered with a collagen sponge into the damaged tracheal cartilage in immunodeficient rats. Human nuclear antigen (HNA)-positive cells were observed in all six rats at 4 weeks and in six out of seven rats at 12 weeks after transplantation, indicating that transplanted iMSCs survived within the tracheal cartilage defects of rats. The HNA-positive cells coexpressed SOX9, and type II collagen was detected around HNA-positive cells in four of six rats at 4 weeks and in three of seven rats at 12 weeks after transplantation, reflecting cartilage-like tissue regeneration. These results indicate that the transplanted iMSCs could differentiate into chondrogenic cells and promote tracheal cartilage regeneration. iMSC transplantation thus represents a promising approach for human tracheal reconstruction.</p>","PeriodicalId":56375,"journal":{"name":"Tissue Engineering Part A","volume":" ","pages":"398-408"},"PeriodicalIF":3.5,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141545582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimized Biomanufacturing for Treatment of Volumetric Muscle Loss Enables Physiomimetic Recovery.","authors":"Rachel K Bour, Gavin T Garner, Shayn M Peirce, George J Christ","doi":"10.1089/ten.TEA.2023.0315","DOIUrl":"10.1089/ten.TEA.2023.0315","url":null,"abstract":"<p><p>Volumetric muscle loss (VML) injuries are defined by loss of sufficient skeletal muscle to produce persistent deficits in muscle form and function, with devastating lifelong consequences to both soldiers and civilians. There are currently no satisfactory treatments for VML injuries. The work described herein details the implementation of a fully enclosed bioreactor environment (FEBE) system that efficiently interfaces with our existing automated bioprinting and advanced biomanufacturing methods for cell deposition on sheet-based scaffolds for our previously described tissue-engineered muscle repair (TEMR) technology platform. Briefly, the TEMR technology consists of a porcine bladder acellular matrix seeded with skeletal muscle progenitor cells and preconditioned via 10% uniaxial cyclic stretch in a bioreactor. Overall, TEMR implantation in an established rat tibialis anterior (TA) VML injury model can result in 60 to ∼90% functional recovery. However, our original study documented >50% failure rate. That is, more than half of the implanted TEMR constructs produced no functional improvement beyond no treatment/repair. The high failure rate was attributed to the untoward mechanical disruption of TEMR during surgical implantation. In a follow-up study, adjustments were made to the geometry of both the VML injury and the TEMR construct, and the \"nonresponder\" group was reduced from over half the TEMR-treated animals to just 33%. Nonetheless, additional improvement is needed for clinical applicability. The main objectives of the current study were twofold: (1) explore the use of advanced biomanufacturing methods (i.e., FEBE bioreactor) to further improve TEMR reliability (i.e., increase functional response rate), (2) determine if previously established bioprinting methods, when coupled to the customized FEBE system would further improve the rate, magnitude or amplitude of functional outcomes following TEMR implantation in the same rat TA VML injury model. The current study demonstrates the unequivocal benefits of a customized bioreactor system that reduces manipulation of TEMR during cell seeding and maturation via bioprinting while simultaneously maximizing TEMR stability throughout the biofabrication process. This new biomanufacturing strategy not only accelerated the rate of functional recovery, but also eliminated all TEMR failures. In addition, implementation of bioprinting resulted in more physiomimetic skeletal muscle characteristics of repaired muscle tissue.</p>","PeriodicalId":56375,"journal":{"name":"Tissue Engineering Part A","volume":" ","pages":"373-386"},"PeriodicalIF":3.5,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141238840","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vascularization of Human Acellular Dermal Matrices: A Comparative Study in a Nonhuman Primate Model.","authors":"Victoria Stefanelli, Jared Lombardi, Joselito Ferrer, Maryellen Gardocki-Sandor","doi":"10.1089/ten.TEA.2024.0059","DOIUrl":"10.1089/ten.TEA.2024.0059","url":null,"abstract":"<p><p>Four human acellular dermal matrices (hADMs) were characterized in a nonhuman primate abdominal wall repair model by evaluating host immune response, vascularization, and incorporation into host tissues. AlloDerm™ (electron beam-sterilized hADM [e-hADM]), AlloMax™ (gamma beam-sterilized hADM, freeze-dried [g-hADM-FD]), DermaMatrix™ (hADM, freeze-dried [hADM-FD]), and FlexHD™ (ethanol-treated hADM [EtOH-hADM]) were each implanted in an abdominal wall-bridging defect in nonhuman primates (<i>n</i> = 3 animals/time point, <i>n</i> = 36 animals). Immunohistochemical and histological assessments were conducted on biopsies from each hADM at 1-, 3-, and 6-months postimplantation to assess vascularization (hematoxylin and eosin [H&E], CD31, alpha smooth muscle actin [αSMA], collagen IV), inflammatory/immune response (H&E, CD3, CD20, CD68), and collagen turnover (H&E, matrix metalloproteinase-9 [MMP-9]). MMP-9 immunolabeling was similar among different hADMs at 1 month; however, hADM-FD and EtOH-hADM showed higher total mean MMP-9-immunopositive areas at approximately 16% compared with <1% for e-hADM and g-hADM at 6 months postimplantation. Cells that stained positively for CD68, CD3, and CD20 were generally higher for hADM-FD and EtOH-hADM compared with other hADMs. The mean CD31-immunopositive area, CD31 vessel density, CD31 vessel diameter, and collagen IV-immunopositive area increased over time. Among all the hADM types, e-hADM had the highest mean (±standard deviation [SD]) CD31-immunopositive area at 1.54% ± 1.01%, vessel density at 7.86 × 10^-5 ± 3.96 × 10^-5 vessels/µm², and collagen IV-immunopositive area at 2.55% ± 0.73% 1-month postimplantation. The pattern of αSMA immunolabeling varied among the hADMs. Histology showed that overall inflammation was mild at 1 month. Overall fibroblast repopulation and collagen remodeling increased over time from 1 to 6 months postimplantation. Fibroblast infiltration was minimal to mild at 1 month, with e-hADM showing the highest mean (±SD) score at 2.00 ± 0.00 compared with other hADMs. Only hADM-FD was not completely replaced by neotissue formation at 6 months postimplantation. All hADMs promoted vascularization, cell infiltration, and incorporation into host tissue, which were associated with acute inflammation and immune responses, within a 6-month period. A trend toward relatively enhanced early vascularization in e-hADM compared with other hADMs was observed. Immunogenic responses among the hADMs in the present study showed a slight distinction toward more quiescent terminally sterilized hADMs (e-hADM, g-hADM-FD) versus aseptically processed hADMs (EtOH-hADM, hADM-FD).</p>","PeriodicalId":56375,"journal":{"name":"Tissue Engineering Part A","volume":" ","pages":"419-432"},"PeriodicalIF":3.5,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141749810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bi-layered Adipose Mesenchymal Cell Sheets Improve Bladder Compliance in Spinal Cord-Injured Rats.","authors":"Yuki Matsumoto, Tetsuya Imamura, Ryo Kitahara, Yoshihiro Inoue, Tetsuichi Saito, Manabu Ueno, Tomonori Minagawa, Teruyuki Ogawa, Osamu Ishizuka","doi":"10.1089/ten.TEA.2024.0115","DOIUrl":"10.1089/ten.TEA.2024.0115","url":null,"abstract":"<p><p>To improve bladder compliance in patients with low-compliance bladders, augmentation cystoplasty with the intestinal tract is performed. However, the use of the intestinal tract often leads to serious surgical complications. Tissue engineering technologies have the potential to improve bladder compliance without using the intestinal tract. In this study, we fabricated bi-layered adipose-derived mesenchymal cell (AMC) sheets and then determined whether the bi-layered AMC sheets could improve bladder compliance in rats with spinal cord injury (SCI). The abdominal adipose tissues of green fluorescence protein (GFP)-transfected Sprague-Dawley (SD) rats were harvested, and the attached and proliferating cells on type I collagen were used as AMCs. The AMCs were then cultured on temperature-responsive culture dishes. After reaching over-confluence, the AMCs that maintained cell-cell contacts were detached from the dishes and applied to a gelatin hydrogel sheet. Then, another detached AMC monolayer was accumulated on the AMC monolayer-applied gelatin. Prior to 4 weeks of transplantation, the levels of T8-9 in the spinal cords of recipient SD rats were partially transected. After producing the bi-layered AMC sheets and the rats with SCI, the detrusor muscles of the anterior bladder walls of the rats with SCI were incised, and the bi-layered AMC sheet was patch-transplanted onto the exposed bladder epithelium (<i>n</i> = 8). As a control, the sham operation was performed (<i>n</i> = 7). Four weeks after the transplantation, bladder capacity and bladder compliance in AMC sheet-transplanted SCI rats were significantly higher than those in sham-operated control SCI rats. The smooth muscle layers in AMC sheet-transplanted bladders were significantly larger than those in control bladders. In addition, the collagen fibers in the AMC sheet-transplanted bladders were significantly smaller than those in the control bladders. Some GFP-positive transplanted AMCs differentiated into smooth muscle actin- or desmin-positive cells. Furthermore, GFP-positive cells secreted transforming growth factor-β1 or vascular endothelial growth factor. Therefore, this study showed that bi-layered AMC sheets could improve bladder compliance and bladder tissues in SCI rats.</p>","PeriodicalId":56375,"journal":{"name":"Tissue Engineering Part A","volume":" ","pages":"409-418"},"PeriodicalIF":3.5,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141749808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Incorporating Microbial Stimuli for Osteogenesis in a Rabbit Posterolateral Spinal Fusion Model.","authors":"Nada Ristya Rahmani, Anneli Duits, Michiel Croes, Olivia Lock, Debby Gawlitta, Harrie Weinans, Moyo C Kruyt","doi":"10.1089/ten.TEA.2024.0064","DOIUrl":"10.1089/ten.TEA.2024.0064","url":null,"abstract":"<p><p>Autologous bone grafts are commonly used to repair defects in skeletal tissue, however, due to their limited supply there is a clinical need for alternatives. Synthetic ceramics present a promising option but currently lack biological activity to stimulate bone regeneration. One potential approach to address this limitation is the incorporation of immunomodulatory agents. In this study, we investigate the application of microbial stimuli to stimulate bone formation. Three different microbial stimuli were incorporated in a biphasic calcium phosphate (BCP) ceramic: Bacille Calmette-Guérin (BCG), gamma-irradiated <i>Staphylococcus aureus (</i>γi-<i>S. aureus)</i>, or γi<i>-Candida albicans</i> (γi<i>-C. Albicans</i>). The constructs were then implanted in both a rabbit posterolateral spinal fusion (PLF) and an intramuscular implant model for 10 weeks and compared to a nonstimulated control construct. For the PLF model, the formation of a bony bridge was evaluated by manual palpation, micro computed tomography, and histology. While complete fusion was not observed, the BCG condition was most promising with higher manual stiffness and almost twice as much bone volume in the central fusion mass compared to the control (9 ± 4.4% bone area vs. 4.6 ± 2.3%, respectively). Conversely, the γi-<i>S. aureus</i> or <i>γi-C. albicans</i> appeared to inhibit bone formation (1.4 ± 1.4% and 1.2 ± 0.6% bone area). Bone induction was not observed in any of the intramuscular implants. This study indicates that incorporating immunomodulatory agents in ceramic bone substitutes can affect bone formation, which can be positive when selected carefully. The readily available and clinically approved BCG showed promising results, which warrants further research for clinical translation.</p>","PeriodicalId":56375,"journal":{"name":"Tissue Engineering Part A","volume":" ","pages":"387-397"},"PeriodicalIF":3.5,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142333476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modular, Vascularized Hypertrophic Cartilage Constructs for Bone Tissue Engineering Applications.","authors":"Nicholas G Schott, Gurcharan Kaur, Rhima M Coleman, Jan P Stegemann","doi":"10.1089/ten.tea.2024.0367","DOIUrl":"https://doi.org/10.1089/ten.tea.2024.0367","url":null,"abstract":"<p><p>Insufficient vascularization is the main barrier to creating engineered bone grafts for treating large and ischemic defects. Modular tissue engineering approaches have promise in this application because of the ability to combine tissue types and localize microenvironmental cues to drive desired cell function. In direct bone formation approaches, it is challenging to maintain sustained osteogenic activity, since vasculogenic cues can inhibit tissue mineralization. This study harnessed the physiological process of endochondral ossification to create multiphase tissues that allowed concomitant mineralization and vessel formation. Mesenchymal stromal cells in pellet culture were differentiated toward a cartilage phenotype, followed by induction to chondrocyte hypertrophy. Hypertrophic pellets (HPs) exhibited increased alkaline phosphatase activity, calcium deposition, and osteogenic gene expression relative to chondrogenic pellets. In addition, HPs secreted and sequestered angiogenic factors, and supported new blood vessel formation by cocultured endothelial cells and undifferentiated stromal cells. Multiphase constructs created by combining HPs and vascularizing microtissues and maintained in an unsupplemented basal culture medium were shown to support robust vascularization and sustained tissue mineralization. These results demonstrate a promising <i>in vitro</i> strategy to produce multiphase-engineered constructs that concomitantly support the generation of mineralized and vascularized tissue in the absence of exogenous osteogenic or vasculogenic medium supplements.</p>","PeriodicalId":56375,"journal":{"name":"Tissue Engineering Part A","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144053523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Osteoclast Incorporation in an <i>In Vitro</i> 3D Model of Endochondral Ossification.","authors":"Amaia Garmendia Urdalleta, Janneke Witte-Bouma, Nicole Kops, Andrea Lolli, Eric Farrell","doi":"10.1089/ten.tea.2024.0281","DOIUrl":"https://doi.org/10.1089/ten.tea.2024.0281","url":null,"abstract":"<p><p><i>In vitro</i> models aim to recapitulate human physiological processes, improving upon and replacing the need for animal-based models. Modeling bone formation via endochondral ossification <i>in vitro</i> is a very complex process due to the large number of cell types involved. Most current models are limited to mimicking the initial stages of the process (i.e., cartilage template formation and mineralization of the matrix), using a single cell type. Chondroclasts/osteoclasts are key players in cartilage resorption during endochondral ossification, but their introduction into <i>in vitro</i> models has thus far proven challenging. In this study, we aimed toward a new level of model complexity by introducing human monocyte-derived osteoclasts into 3D <i>in vitro-</i>cultured cartilage templates undergoing mineralization. Chondrogenic and mineralized chondrogenic pellets were formed from human pediatric bone marrow stromal cells and cultured in the presence of transforming growth factor-β3 (TGF-β) and TGF-β/β-glycerophosphate, respectively. These pellets have the capacity to form bone if implanted <i>in vivo.</i> To identify suitable <i>in vitro</i> co-culture conditions and investigate cell interactions, pellets were co-cultured with CD14+ monocytes in an indirect (transwell) or direct setting for up to 14 days, and osteoclastogenesis was assessed by means of histological stainings, osteoclast counting, and gene expression analysis. Upon direct co-culture, we achieved effective osteoclast formation <i>in situ</i> in regions of both mineralized and unmineralized cartilages. Notably, <i>in vitro</i>-generated osteoclasts showed the ability to form tunnels in the chondrogenic matrix and infiltrate the mineralized matrix. Addition of osteoclasts in human <i>in vitro</i> models of endochondral ossification increases the physiological relevance of these models. This will allow for the development of robust 3D human <i>in vitro</i> systems for the study of bone formation, disease modeling, and drug discovery, further reducing the need for animal models in the future.</p>","PeriodicalId":56375,"journal":{"name":"Tissue Engineering Part A","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144021318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}