Chronic wounds do not progress through the wound healing process in a timely manner and are considered a burden for healthcare system; they are also the most common reason for decrease in patient quality of life. Traditional wound dressings e.g., bandages and gauzes, although highly absorbent and effective for dry to mild, exudating wounds, require regular application, which therefore can cause pain upon dressing change. In addition, they have poor adhesional properties and cannot provide enough drainage for the wound. In this regard, the normalization of the healing process in chronic wounds is an extremely urgent task of public health and requires the creation and implementation of affordable dressings for patients with chronic wounds. Modern wound dressings (WDs) are aimed to solve these issues. At the same time, hydrogels, unlike other types of modern WDs (foam, films, hydrocolloids), have positive degradation properties that makes them the perfect choice in applications where a targeted delivery of bioactive substances to the wound is required. This mini review is focused on different types of traditional and modern WDs with an emphasis on hydrogels. Advantages and disadvantages of traditional and modern WDs as well as their applicability to different chronic wounds are elucidated. Furthermore, an effectiveness comparison between hydrogel WDs and the some of the frequently used biotechnologies in the field of regenerative medicine (adipose-derived mesenchymal stem cells (ADMSCs), mesenchymal stem cells, conditioned media, platelet-rich plasma (PRP)) is provided.
Background aimsSpontaneous mutagenesis often leads to appearance of genetic changes in cells. Although human multipotent mesenchymal stromal cells (hMSC) are considered as genetically stable, there is a risk of genomic and structural chromosome instability and, therefore, side effects of cell therapy associated with long-term effects. In this study, the karyotype, genetic variability and clone formation analyses have been carried out in the long-term culture MSC from human gingival mucosa.MethodsThe immunophenotype of MSC has been examined using flow cytofluorometry and short tandem repeat (STR) analysis has been carried out for authentication. The karyotype has been examined using GTG staining and mFISH, while the assessment of the aneuploidy 8 frequency has been performed using centromere specific chromosome FISH probes in interphase cells.ResultsThe immunophenotype and STR loci combination did not change during the process of cultivation. From passage 23 the proliferative activity of cultured MSCs was significantly reduced. From passage 12 of cultivation, clones of cells with stable chromosome aberrations have been identified and the biggest of these (12%) are tetrasomy of chromosome 8. The random genetic and structural chromosomal aberrations and the spontaneous level of chromosomal aberrations in the hMSC long-term cultures were also described.ConclusionsThe spectrum of spontaneous chromosomal aberrations in MSC long-term cultivation has been described. Clonal chromosomal aberrations have been identified. A clone of cells with tetrasomy 8 has been detected in passage 12 and has reached the maximum size by passage 18 before and decreased along with the reduction of proliferative activity of cell line by passage 26. At later passages, the MSC line exhibited a set of cells with structural variants of the karyotype with a preponderance of normal diploid cells. The results of our study strongly suggest a need for rigorous genetic analyses of the clone formation in cultured MSCs before use in medicine.
Background: The search for an effective therapy for local radiation injuries (LRI) is urgent; one option is mesenchymal stem cells (MSC) derived from the placenta and their conditioned medium for the regenerative processes of the skin. Methods: We used 80 animals, randomly assigned to four groups: control (C) animals that did not receive therapy; control with the introduction of culture medium concentrate (CM); introduction of MSCs (PL); introduction of CMPL. LRI modeling was performed on an X-ray machine at a dose of 110 Gy. Histological and immunohistochemical tests were performed. Results: On the 112th day, the area of the open wound surface in the CMPL group was 6.7 times less than in the control group. Complete healing of the open wound surface of the skin in the CM group was observed in 40%, in CMPL 60%, in the PL group 20%, and in the C group there were no animals with a prolonged wound defect. A decrease in inflammatory processes was observed in the CMPL group. Conclusions: the use of a concentrate of conditioned MSCs (CMPL group) in severe LRI in laboratory animals accelerates the transition of the wound process to the stage of regeneration and epithelization.
Purpose: To study the regeneration processes in the treatment of radiation skin lesions with the mesenchymal stem cells (MSC) derived from human gingiva and their conditional medium concentrate (CCM) during animal studies. Material and methods: The study includes 80 white male Wistar rats weighing 210 ± 30 g at the age of 8–12 weeks, randomized into 4 groups (20 animals in each): control group (C), animal did not receive treatment; control with the introduction of the conditional medium concentrate (CCM) three times on days 1, 14 and 21; the introduction of MSC in a dose of 2 million cells per 1 kg three times on days 1, 14 and 21; the introduction of CCM in the estimated dose of 2 million cells per 1 kg three times on days 1, 14 and 21. Radiation burn simulation was performed (using on an X-ray unit at a dose of 110 Gy) and each animal was observed 17 times: at days 1, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91, 98, 105 and 112. Histological (stained with hematoxylin-eosin) and immunohistochemical (CD31, CD68, and VEGF) studies were performed. MSC was cultivated according to the standard procedure up to passages 3–5, the conditioned medium was collected and concentrated 10 times. The MSC immunophenotype (CD34, CD45, CD90, CD105, CD73, HLA-DR) and viability (7-ADD) were determined using flow cytometry. Results: Under the assessment of the animal skin on the day 7 in the CCM group, the area was significantly larger compared to the C, MSC, CM groups (р ≤ 0.05). In the CM group on the day 14 the area of the open wound surface and ulcers from day 28 to day 42 was significantly less, compared with the C, MSC and CCM groups (р ≤ 0.05). In group C, from 42 to 77 days of observation, an increase in the area of skin ulcers was observed compared with the CM and CCM groups (р ≤ 0.05). On the day 112, healing of skin ulcers in the CM group was observed in 40 %, in the MSC group in 60 %, and only in 20 % of animals in the CCM group, and in the C group it was not registered. Expression of VEGF marker on endothelial cells and stromal cells was observed in groups C and CM on day 28 and in groups MSCs and CCM on day 112. On the 28th day in the MSC group, the average number of vessels (CD31) in the field of view was 6.0, and on day 112 it was 12.75, р ≤ 0.05, in the CCM group – 19.10 and 28.6, respectively, р ≤ 0.05. An increase in the number of macrophages (CD68) was found in group C from 28 to 112 days (11.6 and 24.73, р ≤ 0.05), and in the CM group the decrease was 22.1 and 13.07, respectively, р ≤ 0.05. Conclusion: Thus, all used treatment modes of radiation skin lesions, including 3-fold administration of CM, MSC and CCM at a dose of 2 million cells per 1 kg, were effective and resulted in a reduction in the damage area, accelerated ulcer healing, and improvement of the regenerative processes. In addition, the use of MSCs led to the improvement of inflammatory processes’ vascularization and reduction in the radiation skin lesions.
Aim.To develop a safe protocol for cryopreservation of segments of iliac arteries straight after their retrieval from post-mortem donor with the use of polydimethylsiloxane as a coolant and cryoprotectant.Materials and methods.Eleven segments of iliac arteries were retrieved from post-mortem donor and divided into four groups including control. Based on preliminary heat and cold transfer mathematical modeling and tests with tissueequivalent phantom arterial segments were placed on plastic mounts and cryopreserved by following protocol: groups 1 and 2 were immersed in polydimethylsiloxane and cooled rapidly at 180 °С/min to –75 °С. Group 3 segments were cryopreserved at 1,6 °С/min in PDMS – fi lled cryo-container placed in the freezer at –80 °С. All segments were defrosted by immersion in PDMS at +24 °С and then examined for morphology changes by histological methods and SEM. EDS analysis with the use of AzTech software also was performed for Si – content evaluation. Restricted biomechanical tests were conducted for group 2 segments.Results.There were no signifi cant morphological differences between segments of the control and cryopreserved groups except for the segment with slow cooling.Conclusion.Mobile cryopreservation may allow increasing the effi ciency of retrieval of a large number of donor tissues for possible later use in the processing of bioprostheses of blood vessels; or, after decellularization, as well as tissue-specifi c matrices for tissue-engineering blood vessels.
Objective. Isolation of stem cells (SCs) from different parts of the placenta and description of their biological characteristics. Materials and methods. The placenta was obtained from parturient women aged 22 to 39 years (mean age was 29.0 ± 3.7 years) with a normal singleton pregnancy resulting in normal delivery and with written informed consent obtained at 37–41 weeks of gestation after non-invasive (n = 32) or operative (n = 2) delivery. Wharton’s jelly from the umbilical cord and the fetal side of the placenta, the chorionic plate with chorion frondosum, were isolated and cultured to obtain mesenchymal stem cells (MSCs). Morphological evaluation of cell culture, differentiation, immunological characterization (CD34, CD45, CD90, CD105, CD73, HLA-DR (BD Biosciences and Becman Coulter, USA)), assessment of viability using 7-ADD dye on the FACSCanto II flow cytometry facility (Becton Dickinson CA, USA), cell growth, sterility control, analysis of STR (Short tandem repeat) loci polymorphism for identification, karyotyping, and cryopreservation of cell cultures were carried out. Results. Primary cell cultures were isolated from the chorionic plate with chorion frondosum and Wharton’s jelly of the umbilical cord in 100% of cases. MSCs had high proliferative activity and viability (98.0 ± 1.2% 7-ADD) throughout the whole period of cultivation. The growth rate of MSCs from the chorionic plate at P3, P4, and P5 was higher compared to that of MSCs from the Wharton’s jelly during cultivation, p ≤ 0.05. Immunophenotype corresponded to the requirements of International Society for Cellular Therapy: high expression of MSC markers (CD73, CD90, CD105) was detected; hematopoietic and lymphocytic markers were absent (CD34, CD45, HLA-DR). The potential of cells to differentiate in the mesenchymal direction (chondrocytes, osteocytes, adipocytes) was confirmed in all obtained MSCs. In 95% of cases, the cells were of fetal origin. The karyotype of the examined MSC cell lines was normal: 46, XX (female) or 46, XY (male). All cell cultures were tested, cryopreserved, and placed in a biobank. Conclusion. Isolation and evaluation of biological characteristics of human placental stem cells is of great interest and is a promising direction in regenerative medicine due to the simplicity of placenta sampling, the absence of ethical problems, the ability to quickly obtain and accumulate the necessary amount of cell material with a stable genotype and given biological characteristics. Key words: mesenchymal stem cells, placenta, immunophenotype, STR loci polymorphisms, karyotype
Introduction. Urethral stricture is a complex and urgent problem in operative urology. The main problem in the treatment of extended structures of the posterior urethra is the inability to form an adequate urethral site for augmentation urethroplasty with the common buccal graft, which has a priority in the treatment of penile strictures. The use of tissue acellular matrices may be promising in the development of reconstructive urology, which in the future will solve a number of problems associated with augmentation urethroplasty. The purpose of this article is to study the possibility of using a cell-free matrix of a donor artery as a free flat flap for stricture replacement urethroplasty on a model of laboratory animals (rabbits). Materials and methods. Donor blood vessels were Used, which were subjected to detergent-enzymatic perfusion decellularization. To assess the quality of the cell-free matrix, a histological study and an immunohistochemical study were performed. The cell-free flap of the donor artery was fixed to the protein envelope from the side of the simulated defect and posterior on-lay urethroplasty was performed.Results and discussion. The resulting matrix was characterized by the absence of detectable cell nuclei, preserved type I collagen, and a DNA content of no more than 50 ng / mg of tissue. In the postoperative period, normal motor activity of animals, normal urination, weight loss was not observed. The levels of C- reactive protein, creatinine, and urea in peripheral blood 5 months after surgery were within the normal range: 0.285±0.04839 mg / l, 93.5±8.057 mm / l, and 8.35±1.355 mm/l, respectively. If cystourethrography with the help of computer tomography data for stricture of the urethra is not revealed. During magnetic resonance imaging in the axial and sagittal projections, the patency of the urethra was indirectly confirmed. Conclusion. In a laboratory animal model, it was shown that the resulting cell-free flap has in vivo biocompatibility and can be used for replacement urethroplasty of posterior urethral strictures.
Purpose: To study the effect of radiation sterilization at an ultra-high dose of 30 kGy on the cytocompatibility of decellularized vascular scaffolds repopulated with placenta MSCs. Materials and methods: The material of the study were aortas of laboratory animals (rabbits and rats, three vessels for each animal species), which were subjected to detergent - enzymatic perfusion decellularization by two protocols differing in reagents composition. Then the scaffold decellularized by the most efficient protocol was irradiated at a dose of 30 kGy and repopulated with placenta MSCs. As a control, the unirradiated matrix was seeded with cells of the same type. Histological staining of hematoxilin – eosin, IHC for type I collagen and Ki67, DAPI staining and quantitative assessment of genomic DNA were used to evaluate the effectiveness of decellularization and seeding. Scaffolds seeding was assessed by analyzing serial sections taken on day 1st, 3rd, and 4th of culture. Results: The scaffolds obtained in accordance with Protocol 1 were characterized by the absence of detectable cell nuclei, while the DNA content in them was significantly lower compared to Protocol 2. On the digitized images of sections of the unirradiated matrix, the cell nuclei were determined for routine H&E and DAPI staining while for the irradiated scaffold the cell nuclei were visualized on the border between the scaffold and fibrin gel only on DAPI stained section at 1st day of culture. The frequency of occurrence of Ki67+ nuclei on the 4th day of culture was significantly lower for the irradiated scaffold in comparison with the non-irradiated scaffold (7.5% and 29.8%, respectively, p=0.0054). Conclusion: Scaffold irradiation leads to loss of cytocompatibility of tissue-engineering constructs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.