Cell and Tissue Banking最新文献

To compare the differences in biological and biomechanical characteristics of cadaver tendon treated by deep freezing, 95wt.% ethanol, tributyl phosphate (TBP), and sodium dodecyl sulfate (SDS) respectively. A total of 50 fresh tendon specimens were randomly divided into five groups, and four groups were treated with deep freezing (- 80 °C), 95wt.% ethanol, 1% TBP, or 1% SDS, respectively. Hematoxylin-eosin (HE), toluidine blue (TB) and 4',6-diamidino-2-phenylindole (DAPI) staining, and transmission/scanning electron microscope observations were performed. Then, cyclic creep and tensile tests were conducted to investigate the biomechanical properties. The content of residual DNA was tested. The HE, TB and DAPI staining showed a significant decrease in tendon cells following treatments, compared with fresh specimens. SDS, TBP, alcohol can almost completely decellularize the tendon, and deep-frozen group remained a few number of tendon cells. The residual DNA content was significantly lowered, with an average percentage of 50.97%, 79.16%, 88.91% and 72.56%, for groups of deep freezing, alcohol, TBP and SDS, respectively. The arrangement of collagen fibers was significantly disrupted, and the gap between fibers was widened, following treatments by alcohol, TBP and SDS. However, the biomechanical properties were generally similar among the five groups, with significantly lowered cyclic creep for ethanol group and lowered Young's modulus for SDS group exclusively. The four treatments can effectively reduce the number of residual cells and DNA content. Among them, cryogenic treatment has almost no damage to tendon histology and biomechanics, while ethanol, SDS and TBP decellularization methods cause different degrees of damage.

To qualify for bone donation many criteria must be met. For procurement, two time intervals-a postmortem interval (PMI) of 6 h (hours) until cooling of the deceased and a maximum procurement time of tissues within 24/36 h postmortem are mandatory. Expanding the procurement to donors with a longer PMI would be helpful e.g. to have more time to contact relatives for consent for donation. A loss of biomechanical quality of bone tissues should not be expected in the PMI until procurement, but the question of microbiological contamination remains. Therefore, samples from the iliac crest were procured under standard procurement conditions between 48 and 54 h (n = 14, group 1) and 72-78 h (n = 7, group 2) postmortem (pm). Samples were immediately frozen after procurement at < - 18 °C and sent to the German Institute for Tissue and Cell Replacement (DIZG) for mechanical preparation. Additionally, chloroform treatment was performed at the tissue bank of the Charité Berlin. After each step the samples were refrozen and sent to a contracted microbiological lab for bioburden testing according to the European Pharmacopoeia. Samples were tested after procurement, preparation, and chloroform treatment respectively. As acceptance criterion a maximum amount of 9 × 10⁴ colony forming units per gram (CFU/g) tissue was defined. All samples were within the defined limit with a maximum value of 2.5 × 10² CFU/g. These values are in the range of bone tissues procured under non-strict-aseptic procurement conditions within 24 or 36 h and are within the capacity of the peracetic acid sterilization process used by several tissue banks.

Despite significant progress in cartilage regeneration therapeutics, several challenges remain in achieving optimal results under in vivo conditions. The present research evaluated the chondrogenic potential of poly(glycerol sebacate) copolymer nanofibrous scaffold (PGS NF) loaded with growth differentiation factor-5 incorporated sugar glass nanoparticles (SGnP-GDF5), in combination with allogenic bone marrow-derived mesenchymal stem cells (BM-MSC) in a rabbit model. A full-thickness chondral defect of 4 mm diameter was created in the trochlear facet of the left femur of rabbits using a Brad point drill bit. PGS NF was used in group B, BM-MSC laden PGS NF in group C, SGnP-GDF5 loaded PGS NF in group D, and BM-MSC laden SGnP-GDF5 loaded PGS NF in group E. Five animals from each group were sacrificed on days 60 and 90 post-treatment. The samples were assessed based on gross morphology, histopathology, scanning electron microscopy (SEM), and micro-computed tomography (micro-CT) analysis to evaluate regeneration. The SGnP-GDF5 PGS NF group and the BM-MSC laden SGnP-GDF5 PGS NF group exhibited superior cartilage regeneration, closely resembling hyaline cartilage. Histopathological evaluation revealed a columnar pattern of chondrocytes, along with an optimal concentration of proteoglycans and collagen in the extracellular matrix of the newly formed cartilage, indicating robust regeneration in both groups. Furthermore, the SEM and micro-CT analysis findings highlighted the exceptional quality of the repaired tissue in these groups. The release of GDF5 from SGnP and the expedient microenvironment provided by the NF scaffold augmented chondrogenic differentiation, resulting in superior cartilage tissue regeneration.

Cardiovascular diseases have become the leading cause of death worldwide in recent years. Therefore, blood vessel transplantation is an alternative to reduce complications and deaths resulting from cardiovascular diseases. Therefore, this study aims to analyze specific family refusal to donate blood vessels for transplantation in an Organ Procurement Organization. This is a cross-sectional study carried out in accordance with Family Authorization for Organ and Tissue Donation Terms of patients diagnosed with brain death by an Organ Procurement Organization in the state of São Paulo, Brazil. The variables analyzed were sex, age, cause of death, hospital institution and refusal to donate blood vessels. Descriptive and inferential data analysis was performed. Of 2,447 donors, 37.71% refused to donate vessels, influenced by sex, age group of 41-59 years, traumatic brain injury as the cause of death and public hospitals. Refusal varied with age, as it decreased up to 11 years and increased after 60 years. From 2001 to 2020, refusal decreased by 57%, 64%, 68% and 69% for the age groups of 12-19 years, 20-40 years, 41-59 years and 60 years and over, respectively. Donors from public institutions were 18% less likely to refuse donation. Refusal to donate blood vessels for transplantation was associated with all variables analyzed. More research is needed to support strategies that reduce the rejection of these tissues.

Mesenchymal Stem cells (MSCs) have a wide range of therapeutic applications due to their self-renewal and multi-lineage differentiation ability; large-scale production of MSCs is possible only with a highly efficient medium, which facilitates increased proliferation of MSCs within a short period. Recently, Human Platelet Lysate (hPL) has emerged as a promising substitute for fetal bovine serum (FBS) for cell expansion. The goal of this study is to optimize a stable gel formulation for the 3D expansion of MSCs using hPL as a matrix material for the improved proliferation of Human Umbilical Cord Tissue derived MSCs (hUCT-MSCs) in comparison to FBS and hPL-supplemented media in 2D culture. To assess the potential benefits of the hPL gel system, in promoting cell proliferation capacity, hUCT-MSCs were cultured on hPL gel coated-dish supplemented with hPL CM, and in FBS CM. Among the varying concentrations, 20% hPL gel was optimized to have more functional stability and shorter gelation time. SEM analysis and gel degradation study at different concentrations revealed the structural integrity and morphology of the gel. Microscopic images and histological staining by H&E were conducted to understand the multi-layered proliferation of hUCT-MSCs in hPL Gel. Flow cytometry analysis reported the expression of positive markers for human umbilical cord MSCs, namely CD 90⁺ and CD 105⁺, in hPL Gel and hPL Complete Medium (CM) similar to that in FBS. The CCK8 Assay carried out for each culture system, generated OD values respective to cell viability and proliferation. OD values of 1.65 nm, 1.27 nm, and 0.92 nm on average were observed for hPL Gel, hPL CM, and FBS control, respectively. Cells in hPL gel showed a 50% higher proliferation rate of viable cells compared to other culture media. AO/EtBr staining with FBS CM, hPL CM, and hPL gel revealed an increase in viable cells and a decrease in early apoptotic and necrotic cells in hPL Gel. In conclusion, the results of this study highlight the potential of hPL-based gels as superior matrices for multi-layered and enhanced proliferation of hUCT-MSCs.

Tibial reconstruction for major bone loss is a challenging surgical situation. For more than 30 years, massive bone allografts entered our therapeutic arsenal as a major tool to reconstruct large bone defect. Despite allograft is valued for its convenience, it is still burdened by a high complication rate. This retrospective monocentric study focuses on the clinical outcomes of massive tibial allografts and their outcome's prediction. Between 1987 and 2022, the files of 148 massive tibial allografts were retrospectively reviewed (registration number B403201523492). Survival curves were calculated based on the allograft success or failure. Survival curves without revision surgery were calculated following the same design. Finally, multiple logistic regression models were set up to point out variables that influence the allograft survival. After 30 years, 87.2% of the patient retained limb function. However, 55% of the allograft failed and had to be removed (mean survival time is 20.06 ± 2.07 years (CI 16.0-24.1)). The estimate mean survival time is 10.26 ± 1.60 years (CI 7.1-13.4) with less than 20% survival for the allografts without revision surgery after 30 years. Tumor and septic indications worsen the prognosis as well as the number of revision surgeries and the osteochondral allograft type. In contrast, PSI use or traumatological indications improve the allograft survival. Despite remaining an excellent surgical reconstructive option, massive tibial allografts show a high revision surgery rate. Thanks to our multiple logistic regression models, we can start to predict and improve the final outcomes of these complex allograft reconstruction.

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.