To evaluate the influence of dextran-containing versus dextran-free organ culture media on graft preparation characteristics and postoperative outcomes following Descemet Membrane Endothelial Keratoplasty (DMEK). In this single-center retrospective comparative study, 31 organ-cultured corneoscleral donor rims obtained from the Eye Bank of the University Hospital of Cologne between 2018 and 2022 were analyzed. Donor age ranged from 52 to 74 years. Donor tissues were allocated to either dextran-containing organ culture medium (group A, n = 16) or dextran-free medium (group B, n = 15) according to logistical and surgical scheduling considerations. Intraoperative graft preparation characteristics were assessed using a standardized scoring system evaluating Descemet membrane splitting and stripping behavior, graft fragility, and central and peripheral attachment tendencies. Postoperative outcome parameters included Best Spectacle-Corrected Visual Acuity (BSCVA), central and peripheral corneal thickness (CCT and PCT), endothelial cell count (ECC), and re-bubbling rate over a follow-up period of 12 months after DMEK. All 31 DM-endothelium grafts were successfully prepared and transplanted for DMEK. No significant differences were observed between swollen and dextran-deswollen grafts regarding intraoperative preparation characteristics, including stripping behavior (p = 0.722), graft fragility (p = 0.433), peripheral attachment tendency (p = 1.000), and central tearing tendency (p = 0.484). Descemet membrane splitting behavior was also comparable between groups. At 12 months postoperatively, no significant differences were detected between groups regarding CCT (group A: 517.67 ± 15.10 µm vs. group B: 530.10 ± 24.92 µm; p = 0.189) or re-bubbling rate (p = 0.704). A trend toward lower PCT was observed in group B (group A: 604.00 ± 21.67 µm vs. group B: 579.50 ± 36.12 µm; p = 0.063), accompanied by a trend toward higher ECC in group B (group A: 1387 ± 131 cells/mm3 vs. group B: 1692 ± 242 cells/mm3; p = 0.066). BSCVA at 12 months was significantly better in the dextran-free group (group A: 0.08 ± 0.38 logMAR vs. group B: 0.03 ± 0.13 logMAR; p = 0.032). Swollen and dextran-deswollen donor grafts demonstrated comparable intraoperative preparation characteristics and similar postoperative outcomes following DMEK. The slightly improved visual outcomes observed in the dextran-free group suggest that dextran supplementation during organ culture may not be necessary for DMEK graft preparation. Avoiding dextran may further reduce time and costs in corneal eye banking. Larger prospective studies are warranted to confirm these findings.
The objective was to map the stages and costs of processing donated corneal tissue for transplantation in Eye Banks. The method followed the JBI Institute Reviewer’s Manual, and the PRISMA-ScR guidelines were adopted for reporting, to answer the question: “What are the stages and costs of processing donated corneal tissue for transplantation in Eye Banks?” Studies considered for inclusion comprised qualitative, quantitative, mixed-method, observational, experimental, quasi-experimental studies, reviews, institutional documents, manuals, theses, and dissertations, all available in full text and open access, with no restrictions on language or publication period. Information sources included PubMed, Embase, Cochrane Library, Scopus, Web of Science, ScienceDirect, CINAHL (EBSCOhost), the Virtual Health Library, and gray literature databases. The systematic search resulted in the final inclusion of seven studies. The results identified an operational workflow comprising three main phases: corneal selection and recovery, processing and evaluation, and the pre-surgical stage. The review revealed extensive variation in evaluation and discard/disqualification protocols across institutions and countries, especially in those with decentralized regulation. A lack of cost analyses and economic data was identified. In conclusion, although the processing workflow was mapped, the lack of protocol uniformity and, above all, the absence of cost data limit the understanding of financial impact and the sustainability of Eye Banks, reinforcing the need for future research with an economic focus and the development of standardized indicators.
Critical-sized bone defects remain a major clinical challenge in veterinary orthopaedics due to limited intrinsic regenerative capacity and the drawbacks of conventional grafting options. This study reports the development and systematic evaluation of a novel bioinspired osseous scaffold engineered from decellularized bubaline cancellous bone granules, collagen gel, and polycaprolactone, with optional enrichment using autologous adipose-derived stromal vascular fraction. Scaffold physicochemical characteristics—including porosity, material density, and ultrastructure—were assessed through liquid displacement assays, histomorphometry, and scanning electron microscopy, confirming complete decellularization, interconnected porosity, and favourable matrix architecture. Mechanical testing demonstrated significantly enhanced tensile strength in the composite scaffold compared with plain acellular bone–collagen constructs. In vitro biocompatibility was validated by adipose derived mesenchymal stem cell adhesion, proliferation, and migration, with DAPI staining confirming uniform cellular distribution and robust scaffold–cell interactions, along with Alizarin Red S Staining for assessment of osteogenic mineralization.
Human brain tissues obtained from autopsies, as well as muscle and nerve samples derived from biopsies, constitute indispensable resources for translational research investigating the pathomechanisms of neuropsychiatric disorders. In this study, we introduce the Nervous System Tissue Bank of University of Debrecen, which contains formalin-preserved and formalin-fixed paraffin-embedded (FFPE) brain samples, as well as frozen nerve and muscle biopsy specimens. Database was established containing clinical and pathological parameters. For autopsy cases, the following variables were recorded: sex, age, number of hospitalization days, admission diagnosis, comorbidities, cause of death, post-mortem interval, general autopsy findings, and macro- and microscopic brain pathology diagnoses. For biopsy samples, we recorded: sex, age, biopsy site, and microscopic and molecular genetic diagnoses. Based on the recorded parameters and their temporal changes, retrospective statistical analyses were performed. Formalin-fixed brain samples and FFPE blocks were available from 2425 deceased individuals, and nerve/muscle samples from 257 patients. The brain samples originate from the period between 1990 and 2012. The most frequent admission diagnoses included ischemic stroke (n = 1070), hemorrhagic stroke (n = 462), subarachnoid hemorrhage (n = 102), epilepsy (n = 103), brain metastasis (n = 70), primary brain tumor (n = 60), parkinsonism (n = 28), dementia (n = 21), and amyotrophic lateral sclerosis (n = 21). Prevalence of hypertension (67.6
This study aimed to analyze factors associated with the loss of quality of corneas stored in hypothermic preservation media during processing and evaluation in an eye bank. A cohort study was conducted using records from 422 donors (844 corneas) between January 1, 2022, and March 31, 2024. Corneal quality was determined through slit-lamp biomicroscopy based on 13 morphological criteria, with tissues classified on a Likert-type scale from 0 (excellent) to 4 (unacceptable). For analysis, corneas were grouped as higher quality (scores 0–2: excellent, good, and fair) and lower quality (scores 3–4: poor and unacceptable). The outcome was defined as progression from higher to lower quality between the first and second evaluations. No statistically significant associations were found between donor clinical or sociodemographic variables and progression to lower quality. The relative risk (RR) of progression to the lower-quality group according to the storage medium (Optisol-GS vs Eusol-C) was low, RR 1.01 (95
Tissue engineering holds significant promise for advancing pediatric reconstructive surgery by overcoming the limitations of conventional autografts and static implants while harnessing the unique regenerative potential of developing tissues. This review aims to synthesize recent progress and ongoing challenges in pediatric tissue engineering, with a primary focus on the development, design, and clinical translation of biomaterial scaffolds. We examine how scaffold architecture, material composition, and fabrication strategies can be tailored to accommodate pediatric growth, dynamic mechanical demands, and long-term biological integration. While complementary approaches such as stem cell therapies, computational modeling, and disease-specific platforms are acknowledged, the central emphasis remains on scaffold-based solutions that address the distinct anatomical and physiological requirements of children. By moving beyond adult-centric treatment paradigms, the field is gradually shifting toward a more integrated regenerative surgery framework that prioritizes adaptive tissue remodeling and functional recovery. Ultimately, this review highlights how purpose-built scaffolds and emerging biofabrication techniques are paving the way for safer, more effective reconstructive options in pediatric care, while identifying the key translational and regulatory barriers that must be addressed to realize their full clinical potential.
Articular cartilage defects present a significant clinical challenge due to the tissue’s limited self-repair capacity. Tissue-engineered scaffolds that support cell survival, phenotype maintenance, and extracellular matrix (ECM) formation offer a promising strategy for restoring hyaline cartilage. In this study, we synthesized a composite scaffold composed of naturally derived biomaterials alginate and chitosan (AC), and a variant supplemented with type II collagen (CAC), and evaluated their pro-chondrogenic potential. Rabbit nasal septal chondrocytes (NSCs) were selected as the cellular component because of their high proliferative capacity and phenotypic stability. NSCs were seeded on to AC and CAC scaffolds and cultured for up to six weeks. Cell presence and distribution, histological morphology, ECM deposition, chondrogenic marker expression, and mechanical properties were assessed. Live/Dead imaging demonstrated sustained live-cell presence in both scaffold-types across all time-points. Histological analysis confirmed cellular infiltration into the scaffold interior, and Saf-O staining showed pericellular red staining at later time -points, suggestive of matrix deposition. Immunohistochemistry revealed increased staining over time of Sox9, aggrecan, and type II collagen, with CAC scaffolds exhibiting earlier temporal changes in aggrecan and type II collagen expression. Mechanical testing of cellular AC scaffolds showed a 15-fold increase in stiffness post-culture. These findings suggest that AC-based scaffolds, provide a supportive microenvironment for NSCs to infiltrate and express key chondrogenic markers. This composite system represents a simple and adaptable platform with potential utility for engineering cartilage.
Efficient endothelialization is essential for vascular graft integration and long-term performance, yet strategies to enhance endothelial proliferative activity remain limited. Photobiomodulation (PBM) is a promising noninvasive approach for modulating cell behavior, although its effects on endothelial cells under standard culture conditions remain insufficiently defined. This in this study evaluated the effects of 660 nm PBM at different energy densities on the proliferative activity and viability of human umbilical vein endothelial cells cultured under nonstress conditions. Cells were assigned to four groups: nonirradiated control and PBM-treated groups exposed to 1.0, 4.0, or 7.5 J/cm2. Metabolic/proliferative activity and viability were assessed at 24, 48, and 72 h using Alamar Blue, Live/Dead staining, Annexin V/propidium iodide labeling, cell cycle analysis, and Ki67 fluorescence intensity. At 72 h, all irradiated groups showed significantly greater metabolic activity than the control group (1.0 J/cm2, p < 0.01; 4.0 and 7.5 J/cm2, p < 0.001), whereas viability remained high across all groups (> 95
Bone regeneration follows a tightly coordinated biological sequence in which inflammatory resolution, vascular formation, and matrix mineralization occur within distinct temporal windows. However, most current exosome delivery strategies primarily extend retention rather than synchronize therapeutic signaling with these dynamic healing stages. This mismatch between release kinetics and biological demand may limit the regenerative potential of extracellular vesicle therapies. This review proposes a biology-driven framework that reinterprets stimuli-responsive hydrogel systems according to their capacity to coordinate stage-specific exosome delivery throughout bone healing. Recent literature on hydrogel-based exosome delivery systems was critically analyzed and interpreted according to their ability to regulate therapeutic timing rather than stimulus type, encompassing endogenous-responsive, externally triggered, and hybrid platforms. Particular emphasis was placed on release kinetics, osteoimmunomodulation, angiogenic coupling, translational feasibility, and emerging adaptive delivery concepts. Current preclinical evidence suggests that stimuli-responsive hydrogels capable of synchronizing exosome release with successive stages of bone healing may improve inflammatory regulation, vascularization, and osteogenesis compared with passive delivery systems. However, these biological effects remain dependent on hydrogel formulation, exosome source, and experimental model. Multi-responsive and adaptive platforms appear particularly promising for achieving sequential therapeutic signaling, although most remain at the proof-of-concept or preclinical stage. Rather than functioning solely as sustained-release carriers, future exosome delivery systems are likely to evolve toward adaptive therapeutic platforms capable of integrating microenvironment sensing with programmable release behavior. The biology-driven framework proposed in this review provides a complementary perspective for the rational design of next-generation regenerative biomaterials while highlighting the key experimental and translational challenges that must be addressed before clinical implementation.
This research evaluated the effectiveness of platelet-rich fibrin (PRF) membrane alone versus the combined use of PRF membrane and biphasic calcium phosphate (BCP) block as a scaffold for gingival mensenchymal stem cells (GMSCs) in treatment of induced vertical alveolar ridge defects. Three standardized saddle-type defects were created in 10 adult mongrel dogs. Following a 4-week recuperation period, the defects were randomly assigned to one of three groups based on the treatment protocol: group I: defects augmented with only PRF membranes loaded with GMSCs, group II: treated with a combination of PRF membranes loaded with GMSCs and BCP block, and group III: treated with PRF membranes not loaded with GMSCs in addition to BCP block. After four months of augmentation procedures, histological and histochemical examinations were done. Two dogs were excluded from the study, resulting in a total sample size of 8 mongrel dogs. The data were statistically examined. Group II had the largest amount of bone growth inside the defect. However, evidence of bone maturation was more visible in group I. The difference in bone formation inside the defect between groups I and II was not statistically significant (P = 0.3395). However, there were significant differences between groups I and III and groups II and III (P < 0.0001). Histomorphometry revealed that group II had the highest mean area percentage of bone matrix, whereas group III had the lowest mean value. In conclusion, the combination of PRF loaded with MSCs and BCP block is a promising therapy option for vertical alveolar ridge defects in the future.
Burn injuries cause significant damage to the skin and underlying tissues. This damage can lead to life-threatening complications due to the loss of the body’s natural protective barrier. In severe cases, doctors often treat burns by surgically removing dead tissue and performing skin grafts, usually along with antibiotic therapy. However, burn wounds are very vulnerable to infection. Pseudomonas aeruginosa is one of the most common germs found in burn wound infections. Its growing resistance to antibiotics, especially in hospitals, creates a major challenge for treatment. Mesenchymal stromal cells (MSCs) have emerged as a promising option for managing burn wounds. Besides their ability to promote healing, MSCs can also regulate the immune response and fight infections. At the injury site, MSCs manage inflammation, encourage the growth of new blood vessels, and aid tissue repair through signaling molecules like growth factors, cytokines, and chemokines. Additionally, MSCs help the immune system by releasing antimicrobial peptides and proteins (AMPs) and by boosting the activity of immune cells such as phagocytes. This review elucidates the therapeutic potential of MSCs in managing burn wound infections caused by P. aeruginosa. By synthesizing findings from recent studies, it underscores the multifaceted role of MSCs in combating P. aeruginosa infections through their antibacterial, antibiofilm, and regenerative properties, offering a promising approach to address the challenges of antibiotic-resistant burn wounds.
The clinical management of dental caries encompasses a spectrum of therapeutic approaches, ranging from conservative restorative procedures to complex endodontic interventions. In cases involving pulp exposure or reversible pulpal injury, vital pulp therapy procedures are considered essential strategies for preserving pulp vitality and maintaining tooth function. This explains the focus of some recent works on developing tissue engineering (TE) approaches, particularly those involving dental stem or progenitor cells, to produce functional dental tissues. Hydrogel-based scaffolds, highly biocompatible three-dimensional (3D) bio/polymeric networks, are particularly attractive because of their ability to mimic the native extracellular matrix and thus serve as suitable scaffolds for tissue engineering, especially for dental pulp regeneration. Their versatility makes them a good candidate for a range of tissue engineering models, and hydrogel-based scaffolds are proving particularly valuable in regenerative medicine. This work reviews both natural and synthetic polymers, focusing on their structures and emerging uses in the regeneration of the dentin–pulp complex.
To evaluate the outcomes of deep anterior lamellar keratoplasty (DALK) using stromal tissues obtained during Descemet membrane endothelial keratoplasty (DMEK) and to compare the effectiveness of fresh versus three-day–stored grafts. This two-center retrospective study included 42 eyes of 42 patients who underwent DALK using DMEK-derived stromal tissues. Patients were divided into two groups: Group 1 (n = 23), in which fresh stromal tissue was used on the day of surgery, and Group 2 (n = 19), in which stromal tissue stored under cold-chain conditions—defined as transportation with the tissue temperature consistently maintained at approximately 4 °C—for three days was used. Preoperative and postoperative evaluations included best-corrected visual acuity (BCVA), intraocular pressure, slit-lamp and fundus examination, and corneal tomography (Pentacam HR; Oculus, Germany). Demographic data, intraoperative characteristics, postoperative graft transparency, and complications were compared between groups. The groups were similar regarding demographic features, surgical indications, anesthesia type, and suture technique (all p > 0.05). Graft transparency did not differ significantly between the groups on postoperative day 1 or at the last visit (p = 0.597, p = 0.890). Double anterior chamber formation occurred in 3 eyes (15.8
Cryopreserved human heart valves and cardiovascular tissues (homografts) are essential for the surgical treatment of congenital and acquired valvular diseases, particularly in pediatric patients, where prosthetic options are limited. To address the clinical demand for high-quality grafts in Israel, Sheba Medical Center, the largest tertiary care hospital in Israel, established a Good Manufacturing Practice (GMP) compliant Cardiovascular Tissue Bank within the public health system. This report presents an overview of the bank’s operation within the Israeli public health system over seven years, covering donor selection criteria, tissue processing procedures, microbiological safety measures, cryopreservation and distribution, as well as protocol optimization and validation. Between 2018 and early 2025, the tissue bank successfully transitioned from basic sterile techniques to full GMP-grade cleanroom operations, implementing validated protocols for decontamination, packaging, and cryopreservation. During this period, 142 donor hearts were processed, yielding 390 cardiovascular tissues, of which 338 were approved for clinical use and distributed to cardiac surgery centers across Israel. This paper provides a comprehensive operational overview of the Sheba Cardiovascular Tissue Bank from 2018 to 2025, describing protocol refinement, tissue procurement, processing, preservation, regulatory compliance, quality control, and distribution. By combining clinical collaboration, rigorous quality control, and GMP-based infrastructure, the bank plays a pivotal role in ensuring the availability of high-quality cryopreserved homografts for Israeli patients, especially pediatric cases with complex congenital heart disease, and provides a sustainable model for hospital-based cardiovascular tissue banking.
This scientific research aimed to study the cholinergic and motor neuron-like cells differentiation potential of human dental pulp stem cells (hDPSCs) within a novel scaffold montmorillonite/poly (vinyl alcohol) (OMMT/PVA) nanofibrous mesh. The chitosan combined with different concentration of OMMT in PVA was synthesized and the main functional groups within OMMT/PVA nanofibers structure were then identified using ATR-FTIR. The probable cytotoxicity of the scaffolds was tested using MTT and LDH assays. hDPSCs underwent the differentiation process within the nanofibers with different concentrations of OMMT (1%, 3%, and 5%) in two separated phases. The differentiation capability of the cells was examined by analyzing the expression profiling of OCT-4, Nestin, GFAP, MBP, ChAT, MAP2, and Islet1, and Cresyl violet staining. Our findings proved that the scaffold could improve the viability and the proliferation rate of all experimental cell groups over the whole period of preinduction and induction phases. Moreover, the expression profile of genes indicated that the number of cells expressing neural-specific markers for those groups in the induction phase was substantially higher than that of the control group. The percentage of neural-specific markers positive cells increased in induced cells within 5% OMMT in PVA, which indicates that scaffolds provide hDPSCs with a suitable microenvironment for growing and differentiating toward desired neural cell lineages as well. Our finding shows that the OMMT/PVA fibrous scaffolds have a promising neuroprotective property and suitable potential for guiding of differentiation in the hDPSCs into motor neuron and cholinergic subtypes.
Human amniotic membrane extract (AME) contains growth factors that contribute to epithelial regeneration and immunomodulation. This review synthesizes current evidence and incorporates our recent preliminary experimental data to identify the critical parameters that influence the extraction efficiency of six key growth factors-EGF, HGF, TGF-β, bFGF, KGF, and NGF-from human amniotic membrane obtained via cesarean delivery. A comprehensive literature analysis was combined with empirical observations from our laboratory using cryogenic pulverization, differential buffer systems, protease inhibition strategies, and post-extraction stabilization techniques. Factor-specific biochemical behavior and matrix interactions were evaluated to outline optimized extraction conditions. Extraction efficiency was strongly dependent on: 1. preservation of epithelial and stromal integrity; 2. cryogenic pulverization for maximal cell lysis; 3. buffer composition, particularly the use of trehalose for protein stabilization; 4. heparin or high ionic strength solutions for releasing matrix-bound factors such as HGF, bFGF, and KGF; 5. EDTA-based protease control for NGF; and 6. sonication-assisted liberation of latent TGF-β complexes. Our practical study data confirm that an extraction protocol incorporating phosphate-buffered saline (PBS), trehalose, and cryo-milling substantially enhances the recovery of EGF, NGF, and TGF-β levels, while the addition of protease inhibitors to PBS and cryo-milling improves the concentrations of HGF, FGF, and TGF-β. AME yield is governed by a constellation of process-dependent variables that can be systematically optimized. Integrating biological tissue properties with precise mechanical and biochemical strategies enables the production of standardized, high potency extracts suitable for clinical and biobanking applications. Establishing these optimized conditions may support the development of GMP-compliant workflows and improve the therapeutic consistency of AME-based products.
Cartilage allotransplantation has been employed for years as an effective remedy for cartilage-related disorders. The storage conditions and duration play a critical role in preserving the quality of fresh human nasal allografts. In this study, human nasal cartilages were stored in a designated medium for 2, 4, 6, 8, 10, and 12 weeks at 4 °C, and their cell viability, biomechanical properties, structural integrity, and sterility were evaluated. Cell viability remained over 70
Hematoma presence in musculoskeletal tissues procured from cadaveric donors is traditionally considered a potential risk factor for microbiological contamination. This perception has led to the frequent exclusion of hematoma-bearing tissues from allograft use, despite limited scientific evidence supporting this practice. We conducted a prospective case–control study on 234 musculoskeletal tissues retrieved from 16 cadaveric donors between September 2023 and December 2024. For each tissue, data on hematoma presence and microbiological culture results were collected. Fisher’s exact test was used to assess the association between hematoma presence and microbiological positivity. Odds ratios (OR) and 95
To describe a practical and efficient prolene suture-guided technique for corneal allogenic intrastromal ring segment (CAIRS) implantation and to evaluate intraoperative difficulties and complications associated with the procedure. Medical records and surgical videos of patients who underwent CAIRS for keratoconus were retrospectively reviewed. All procedures were performed by the same surgeon using standardized femtosecond laser parameters. Donor stromal rings were prepared from residual corneal tissue obtained during keratoplasty procedures. A 5–0 prolene suture was passed from the Bowman’s layer toward the endothelial side to guide ring insertion through a narrow stromal tunnel. Intraoperative challenges, including suture disengagement and tunnel-related issues, were documented and analyzed. Twenty-three eyes of 23 patients were included. Combined CAIRS and collagen cross-linking (CXL) were performed in 78.3
This study assessed pregnant women’s awareness and attitudes toward umbilical cord blood donation and banking, and identified independent factors associated with awareness. This study was conducted in Gaziantep Province, Turkey, between March and June 2025, using a descriptive, cross-sectional design involving 204 pregnant women. Participants were recruited using a non-probability convenience sampling method. Data were collected via an online questionnaire that assessed socio-demographic characteristics and knowledge and attitudes towards umbilical cord blood donation and banking. Awareness levels were categorized as “no knowledge”, “limited knowledge”, and “sufficient knowledge”, and dichotomized as “insufficient” versus “partial/sufficient” for regression analysis. Descriptive statistics and the Chi-square test were used to analyze the data. In addition to descriptive statistics, binary logistic regression analysis was performed to identify independent factors associated with awareness of umbilical cord blood donation and banking. Statistical significance was set at p < 0.05. The average age of the pregnant women was 30.38 ± 4.48. Only 3.9
