Cell and Tissue Banking最新文献

The challenge of ineffective wound healing, leading to chronic conditions necessitates the development of novel therapeutics strategies. Currently, a plethora of ailments have been researched and marketed globally to accelerate angiogenesis, re-epithelization, collagen synthesis, and proliferation. However, clinical translation remains challenging and requires rigorous pre- and post-clinical screening. Here, we have developed a formulation encapsulating Raloxifene, a repurposed drug, aimed to induce accelerated wound healing. Four different formulations (Forms 1, 2, 3, and 4) incorporating alginate, poloxamer 407 (P407), LiCl, and fetal bovine serum were prepared. Formulations were characterized by scanning electron microscopy, Fourier Transformation infrared spectroscopy, and rheology. In vitro assessments encompassing cell viability, cell migration, and drug release profile were conducted, subsequently, the in vivo wound healing potential was evaluated in Sprague Dawley (SD) rats. In results, we observed significant (p-value<0.05) wound healing by Form 3 at  14th due to up-regulation of TGFꞵ, Col-I and GSK3β genes. The histology results showed complete development of epidermis, endoderm and collagen fibers by Form 3, leading to complete healing. This formulation shows promise for clinical application in accelerated wound healing processes.

Two recent tuberculosis outbreaks in the United States implicated a contaminated bone graft product containing living cells. Evidence-based donor selection criteria may help prevent future tragic events like these. However, the development of such criteria must be informed by estimates of the risk of tuberculosis transmission by tissue transplantation, which are currently lacking. Therefore, we aimed to estimate the risk of tuberculosis transmission through tissue transplantation in Québec, Canada. We developed a deterministic model to assess the risk of tuberculosis transmission through the transplantation of skin, cardiovascular, musculoskeletal, and ocular tissues. Transmission risk was estimated according to three scenarios (i.e., most-likely, optimistic, and pessimistic). Except for ocular tissues, the estimated risk was consistently < 1 in 1 million transplantations, even after inflating some parameters by 50% or 100%. In the most-likely scenario, the risk of transmission by ocular tissue transplantation was estimated at only 1 in 312,160. The calculated risk of tuberculosis transmission by tissue transplantation is extremely low in our jurisdiction and does not warrant the implementation of additional risk mitigation measures beyond those currently in place. Albeit low, the estimated risk was higher for ocular grafts in part because they contain living cells, which is not the case of gamma-irradiated tissues. Our work showcases how the selection criteria of tissue donors can be informed by risk estimates derived from mathematical models.

The preservation of key growth factors in the human amniotic membrane (hAM) that are involved in tissue regeneration and wound healing is the primary focus of this research work. Here, we quantified the total protein content and the major growth factors present in different sample preparations of hAM. The membrane is initially processed, dehydrated, and gamma-irradiated and subsequently subjected to histological staining, cytotoxicity assays, and total protein estimation. The ELISA method was used to quantify TGF b1, bFGF, PDGF-BB, VEGF-A, and EGF in three distinct preservation samples: tissue homogenate (AC-H), ball milled powder (AC-P), and lyophilized powder (AC-L). An in-vitro scratch assay was performed to analyse cell migration and wound healing. Higher TGF-b1 and FGF-b concentrations indicate the potential impact of HAM on re-epithelialization and granular tissue formation. For major growth factors, the quantification shows no significant differences between the samples. On treating the wound area with concentrations of 0.4 mg/ml and 0.6 mg/ml, the remaining wound area for AC-H, AC-L, and AC-P are 39.71%, 40.31%, 55.99% and 25.48%, 62.8%, and 29.65%, respectively. This indicates the presence of growth factors in the membrane promotes wound healing and facilitates cell migration and proliferation. This study provides insights into the quantity of key growth factors within the human amniotic membrane, thereby presenting the approach as a viable option for treating chronic wounds. Additionally, as lyophilization preserves more growth factors and offers greater stability and shelf life than other preservation techniques, it may be an appropriate substitute for ball milling.

A prospective clinical study was conducted to evaluate the effectiveness of indigenously prepared amnion-chorion membrane for the management of multiple adjacent gingival recession. 15 healthy subjects, 8 female and 7 male ranging in age from 18 to 55 years, with maxillary anterior and premolar gingival recession defects were included and all the subjects were treated with the Zucchelli technique along with the placement of amnion-chorion membrane. Clinical examination post-surgery revealed healthy gingival tissues with color and texture blending with adjacent tissues. Complete root coverage was obtained in 44 out of a total of 52 sites with percentage mean root coverage accounting to 97.77%. Also, a statistically significant increase in the width and thickness of keratinized tissue was observed (p < 0.01). Long-term, multicentric, randomized controlled clinical trials with a larger sample size are needed in the future to confirm the findings of the present study and explore the potential of amnion-chorion membrane for its use in regenerative periodontics.

Human heart valve homografts, usually donated after death, are banked worldwide to facilitate reconstructive cardiac surgery, which is a necessary procedure to repair both congenital and acquired cardiac defects. Donations of substances of human origin carry a risk of transmitting infection to recipients. As a result, several different precautions are taken to minimise this risk. Testing the tissue product for possible contamination, and carrying out decontamination of the tissue (often through the use of an antibiotic cocktail) are two of the procedures performed routinely in tissue establishments to minimize the risk of transplantation associated infections. This area of clinical practice does not have an established external quality assessment (EQA) Scheme. This report describes an initial pilot scheme of an EQA to investigate the microbiology testing of heart tissue banking, a collaboration between the Scottish National Blood Transfusion Service (SNBTS) and UK National External Quality Assessment Service (UK NEQAS) for Microbiology. The results highlight the differences in practice between different tissue banks, further supporting the need for setting up an EQA on a regular basis and the need to produce a best practice method document to attempt harmonisation of the testing.

Chronic diabetic wounds, such as diabetic foot ulcers, pose a significant health challenge due to their prolonged healing times and high recurrence rates. Conventional treatments are often inadequate, driving interest in advanced therapeutic approaches like biological scaffolds. Decellularized scaffolds, which replicate the extracellular matrix (ECM), have shown potential in promoting tissue regeneration and wound healing. This study evaluated the efficacy of decellularized bovine articular cartilage scaffolds in enhancing wound healing in a preclinical murine model of chronic diabetic wounds. Bovine articular cartilage was decellularized using a combination of chemical and physical processes. The scaffolds were characterized through H and E staining (to assess histomorphological characteristics), FTIR, and SEM analyses to confirm ECM preservation and effective decellularization. Twenty female diabetic BALB/c mice were divided into two groups: a control group (treated with Atrauman Ag® dressings) and an experimental group (treated with decellularized bovine articular cartilage scaffolds). This study examined the effects of decellularization on the structural and chemical properties of the cartilage scaffolds, as well as their impact on wound healing and closure rates in diabetic mice compared to the control group. Mice treated with the decellularized cartilage scaffolds demonstrated a significantly faster wound closure rate (100% closure by day 17) compared to the control group (75% closure by day 17, P < 0.01). Histological analysis revealed more organized epidermal regeneration, fibrin deposition, and granulation tissue formation in the scaffold-treated group. SEM and FTIR analyses confirmed the preservation and integrity of the ECM before and after the decellularization process. Decellularized bovine articular cartilage scaffolds significantly enhance wound healing in chronic diabetic wounds by promoting tissue regeneration and reducing inflammation. These findings suggest that such scaffolds represent a promising therapeutic option for the treatment of chronic diabetic wounds.

Burn injuries in children are a critical public health issue with significant mortality and morbidity. Allogeneic skin grafts, both cadaveric and freshly donated, have been utilized in pediatric burn care since many years, yet their efficacy and safety remain to be systematically assessed. This systematic review (PROSPERO number: CRD42024560654) analyzed studies from 01/2000 to 07/2024 sourced from PubMed. Inclusion criteria targeted RCTs and retrospective studies focused on the use of allogeneic skin grafts in pediatric burn patients. Extracted data were presented in a narrative synthesis and a comprehensive table. Established tools were used for risk of bias assessment. 13 studies were deemed suitable for analysis, with only two qualifying as RCTs. Allogeneic skin grafts have shown promise in managing pediatric burns, especially in resource-limited settings where autografts or skin substitutes are not available. Studies varied in their treatment approaches, with allogeneic grafts often used for more severe burns, suggesting that observed adverse effects may be due to injury severity rather than treatment type. The retrospective nature of the majority suggests a limited level of evidence. Moreover, the heterogeneity among study designs and patient populations makes it difficult to draw definitive conclusions. Allogeneic skin grafts represent a valuable treatment option in pediatric burn care. However, further well-designed RCTs are essential to establish a stronger evidence base for their use and to guide clinical decision-making. The current literature underscores the potential of allogeneic grafts but also the necessity for more nuanced research tailored to pediatric needs.

The orthopaedic surgeries were greatly aided by bone grafting with the use of nanomaterials which provide new strategies for bone regeneration, despite the significant drawbacks of traditional treatments. Hydroxyapatite is one of the bioactive ceramics that has gained substantial research attention due to its biocompatibility, bioactivity and osteointegration ability for the manufacturing of nano bone grafts. The organized complex and porous structures of the human bone tissue is a nanocomposite which consists of both organic and inorganic matrix including hydroxyapatite naturally. Conventional hydroxyapatite was known to provide good adhesion and proliferation of host cells but very low mechanical strength. Hence biomaterial made of hydroxyapatite with various polymers and cross linking agents were used to enhance the mechanical strength of the material. Out of 293 articles obtained from the literature search, only 90 articles met the inclusion criteria about bone regeneration using nano hydroxyapatite materials. The present review addresses the potential capping agents with plant extracts for the synthesis of hydroxyapatite nanomaterials with multi-functional applications include drug delivery for targeting the desired therapeutic effect for bone regeneration with osteoprotective ability and tumour therapy.

Allograft valves offer significant advantages in valve replacement; however, their limited availability from cadaveric or brain-dead donors presents a considerable challenge. This study aims to share our experience in harvesting and preserving Allograft valves from heart transplant recipients, addressing this shortage and streamlining the process. Allograft valves were harvested from patients who underwent heart transplants at our center from October 2007 to October 2022. After sampling of the allograft for quality control, allograft valves were cryopreserved and thawed before implantation. Allograft valves were used in 60 patients who had pulmonary valve replacement (PVR) in or after repaired Tetralogy of Fallot (TOF). Patient data were collected and statistically analyzed. The age of donors was 39.0 ± 186.0 years while the median age of recipients was 5.1 years (interquartile range, 1.5-12.1). After a median follow-up of 2.6 years (interquartile range, 1.0-6.9), the freedom from all-cause mortality was 94.0%, 89.5%, and 89.5% at 5, 10, and 15 years, respectively. Adverse clinical outcomes, occurred in 24 patients (40.0%), while freedom is 64.9%, 53.4%, and 31.7% for 5, 10, and 15 years. Allograft valves bicuspidized (odds ratio, 75.085; 95% confidence interval, 10.100-558.202, P < 0.001) and early postoperative regurgitation (odds ratio, 9.946; 95% confidence interval, 1.034-95.706, P = 0.047) were considered independent risk factors for adverse clinical outcomes. Our study presents our approach to harvesting and preserving allograft valves from heart transplant recipients, demonstrating favorable short to mid-term outcomes when utilized in allograft valves for patients with or after repaired TOF. We recommend vigilant monitoring of early postoperative regurgitation, as it may signal a poor prognosis, and we strongly advise against bicuspidized the implanted allograft valves.

Purpose: This study aimed to develop a bovine ex vivoex vivo model to simulate human donor corneal storage conditions and assess the feasibility of human eye surgeries in bovine eye bulbs.

Methods: Calf eye bulbs (n = 19) were obtained from local slaughterhouses. Ten corneas were excised, with five maintained in hypothermic storage (2-8 °C): corneal quality parameters, including endothelial cell (EC) density (ECD), EC mortality and morphology, corneal transparency, and central corneal thickness, were monitored up to 14 days of preservation. Five corneas were assigned to non-vital imaging techniques to investigate cell and nuclei morphology. Human donor corneas (n = 5) in hypothermic storage were assessed as a control group. Nine bovine eye bulbs were used to mimic human eye surgeries, including capsulorhexis and open-sky vitrectomy with inner limiting membrane (ILM) removal, to evaluate their feasibility in the bovine model.

Results: Calf corneal endothelia exhibited a regular mosaic of hexagonal-shaped cells with oval-shaped nuclei and occurrence of binucleated cells. Calf ECD and EC morphology remained stable during the storage, although EC mortality and CCT increased, and corneal transparency and VECD decreased over time. ECD, EC mortality, and CCT were significantly higher in calf than in human corneas, while corneal transparency was lower. ECD change and EC morphology were statistically comparable between the two species. In the whole eye bulb, the narrow horizontal pupil reduced posterior chamber visualization, necessitating an open-sky approach for vitrectomy and ILM removal. Capsulorhexis was performed following complete iridectomy.

Conclusions: The presented bovine model offers a reliable alternative to human donor tissues for preliminary studies on corneal preservation and ophthalmic surgical procedures.