Cell therapy for retinal degenerative disorders: a systematic review and three-level meta-analysis.

BACKGROUND: Retinal degenerative disorders (RDDs) cause vision loss by damaging retinal neurons and photoreceptors, affecting individuals of all ages. Cell-based therapy has emerged as an effective approach for the treatment of RDDs with promising results. This meta-analysis aims to comprehensively evaluate the efficacy of cell therapy in treating age-related macular degeneration (AMD), retinitis pigmentosa (RP), and Stargardt macular degeneration (SMD) as the most prevalent RDDs. METHODS: PubMed, Scopus, Web of Science, and Embase were searched using keywords related to various retinal diseases and cell therapy treatments until November 25th, 2023. The studies' quality was evaluated using the Joanna Briggs Institute's (JBI) checklist for quasi-experimental studies. Visual acuity measured as LogMAR score was used as our main outcome. A three-level random-effect meta-analysis was used to explore the visual acuity in patients who received cell-based therapy. Heterogeneity among the included studies was evaluated using subgroup and sensitivity analyses. Moreover, meta-regression for the type of cells, year of publication, and mean age of participants were performed. RESULTS: Overall, 8345 studies were retrieved by the search, and 39 met the eligibility criteria, out of which 18 studies with a total of 224 eyes were included in the meta-analysis. There were 12 studies conducted on AMD, 7 on SMD, and 2 on RP. Cell therapy for AMD showed significant improvement in LogMAR (p < 0.05). Also, cell therapy decreased the LogMAR score in SMD and RP (p < 0.01 and p < 0.0001, respectively). Across all conditions, no substantial publication bias was detected (p < 0.05). CONCLUSION: The findings of the study highlight that the application of cell therapy can enhance the visual acuity in AMD, SMD, and RP.

Determination of voiding pressure in infants with normal lower urinary tracts: Exploring the possible effect of sacral development.

OBJECTIVE: To investigate the association between sacral underdevelopment, as defined by subnormal sacral ratio (SR) measurements, with increased maximum detrusor voiding pressure (P det. Max) in infants. METHODS: In this 2007-2015 retrospective cohort study, the medical records of all infants who underwent a pyeloplasty due to congenital ureteropelvic junction obstruction were added. Their P det. Max was evaluated through the suprapubic catheter utilized for urinary drainage intraoperatively, without imposing any additional risk of urethral catheterization on the infant. SR was calculated via the plain kidney, ureter, and bladder (KUB) radiography film obtained during the voiding cystourethrogram (VCUG) evaluation before the surgery. Participants were categorized into SR < 0.74 or SR ≥ 0.74. P det. Max was subsequently compared between these two groups. RESULTS: A total of 45 patients were included in our analysis. Twenty-eight (62.2%) patients had a (SR < 0.74), while 17 (37.8%) had a (SR ≥ 0.74). P det. Max was shown to be significantly higher in the SR < 0.74 compared to the SR ≥ 0.74 group (167.5 ± 60.8 vs. 55.7 ± 17.9 cmH2O, p < 0.001). After adjusting for age and sex, SR remained a significant contributor to P det. Max (p < 0.001). Physiologic detrusor sphincter dyscoordination (PDSD) rate was significantly higher in the SR < 0.74 versus SR ≥ 0.74 group (100.0% vs. 70.6%, respectively; p = 0.005). CONCLUSION: Lumbosacral underdevelopment, as indicated by subnormal sacral ratios, is associated with sphincter-detrusor dyscoordination, which causes PDSD and can ultimately result in higher P det. Max in infants.

Simultaneous primary posterior urethral valves ablation and bladder neck incision may decrease kidney and bladder failure in long-term follow-up in patients with bladder neck hypertrophy and poor bladder function at presentation: report of 301 cases.

OBJECTIVES: To investigate the effects of bladder neck incision (BNI) and primary valves ablation on long-term kidney and bladder function in children with posterior urethral valves (PUV) and bladder neck hypertrophy (BNH). PATIENTS AND METHODS: From 1997 to 2016, a total of 1381 children with PUV were referred to our tertiary hospital. Of these patients, 301 PUV patients with bladder neck hypertrophy need concurrent BNI and valve ablation. All patients were followed up every 3-6 months on regular basis in first 2 post-surgical years and annually then after. The paired t-test and chi-square test were used to perform statistical analysis with p value < 0.05 defined as the level of significance. RESULTS: Mean age at diagnosis was 7.22 ± 2.45 months (ranging from 7 days to 15 months) with a mean follow-up of 5.12 ± 2.80 years. The incidence of hydronephrosis was decreased from 266 (88.3%) at the baseline to 73 (24.3%) patients in long-term follow-up. At baseline, 188 (62.5%) patients were diagnosed with VUR, which decreased to 20 (6.6%) individuals at the end of follow-up. Bladder and renal function were improved in follow-ups following concomitant PUV ablation and BNI. No Myogenic failure was depicted in all patients with BNH. No ureteric reimplantation was needed during the two decades follow-up. CONCLUSION: Simultaneous valve ablation with BNI may present further profits in children with PUV and BNH particularly cases of BNH with poor bladder function at the time of presentation. This method can improve the results of urodynamic and imaging studies after the surgery. We hypothesize every child with PUV presentation who has concurrent vesicoureteral reflux, CKD or persistent hydrourethronephrosis may suffer from secondary bladder neck obstruction. This secondary bladder outlet obstruction must be managed through BNI as the surgical relief.

Stem Cells and Natural Agents in the Management of Neurodegenerative Diseases: A New Approach.

Neurodegenerative diseases refer to a group of neurological disorders as a consequence of various destructive illnesses, that predominantly impact neurons in the central nervous system, resulting in impairments in certain brain functions. Alzheimer's disease, Parkinson's disease, Huntington's disease, multiple sclerosis, and other neurodegenerative disorders represent a major risk to human health. In order to optimize structural and functional recovery, reconstructive methods integrate many approaches now, to address the complex and multivariate pathophysiology of neurodegenerative disorders. Stem cells, with their unique property of regeneration, offer new possibilities in regenerative and reconstructive medicine. Concurrently, there is an important role for natural products in controlling many health sufferings and they can delay or even prevent the onset of various diseases. In addition, due to their therapeutic properties, they have been used as neuroprotective agents to treat neurodegenerative disorders. After decades of intensive research, scientists made advances in treating these disorders so far, but current therapies are still not capable of preventing the illnesses from progressing. Therefore, in this review, we focused on a new perspective combining stem cells and natural products as an innovative therapy option in the management of neurodegenerative diseases.

Ex-Vivo and In-Vivo Expansion of Spermatogonial Stem Cells Using Cell-Seeded Microfluidic Testis Scaffolds and Animal Model.

AIMS: This study was designed to provide both ex-vivo and in-vivo methods for the extraction and expansion of spermatogonial stem cells (SSCs). METHODS: For in-vivo experiments, azoospermic mouse model was performed with Busulfan. Isolation, culture, and characterization of neonate mouse SSC were also achieved. We performed an in-vivo injection of labeled SSCs to the testes with azoospermia. In ex-vivo experiments, extracted SSCs were seeded on the fabricated scaffold consisting of hyaluronic acid (HA) and decellularized testis tissues (DTT). Immunofluorescence staining with PLZF, TP1, and Tekt 1 was performed for SSCs differentiation and proliferation. RESULTS: Several studies demonstrated efficient spermatogenic arrest in seminiferous tubules and proved the absence of spermatogenesis. Transplanted SSCs moved and settled in the basement covering the seminiferous tubules. Most of the cells were positive for Dil, after 4 weeks. An epithelium containing spermatogonia-like cells with Sertoli-like, and Leydig cells were evident in the seminiferous tubules of biopsies, and the IHC staining was significantly positive, 4 weeks after injection of SSCs. The results of the ex-vivo experiments showed positive staining for all markers, which was significantly enhanced in scaffolds of ex-vivo experiments compared with in-vitro seeded scaffolds. CONCLUSION: Ex-vivo SSC differentiation and proliferation using cell-seeded microfluidic testis scaffolds maybe effective for treatment of the azoospermia.

The role of spinal cord tractography in detecting lesions following selective bladder afferent and efferent fibers injury: A novel method for induction of neurogenic lower urinary tract dysfunction in rabbit.

OBJECTIVE: Neurogenic lower urinary tract dysfunction (NLUTD), a challenging disorder, is defined by lack of bladder control due to the abnormalities in neural pathways and can be classified based on the location of lesions within the nervous system, thus investigating the neural pathways can help us to know the site of the lesion and specify the class of the NLUTD. Diffusion Tensor Imaging (DTI) tractography, a noninvasive advanced imaging method, is capable of detecting central nervous system pathologies, even if routine magnetic resonance imaging shows no abnormality. Accordingly, tractography is an ideal technique to evaluate patients with NLUTD and visualize the pathology site within the spine. This study aimed to introduce a novel method of spinal cord injury (SCI) to establish NLUTD in the rabbit and to investigate the potential of tractography in tracing neural tracts of the spinal cord in an induced NLUTD animal model. MATERIALS AND METHODS: An animal model of NLUTD was induced through cauterization of the spinal cord at the level T12-L1 in 12 rabbits. Then rabbits were assessed via DTI, urodynamic studies (UDS), voiding cystourethrogram (VCUG), and pathology assessments using antineurofilament 200 (NF200) antibody, anti-S100, anti-Smooth Muscle Actin, anti-Myogenin, and anti-MyoD1. RESULTS: The tractography visualized lesions within spinal cord fibers. DTI parameters including fractional anisotropy (FA) value and tract density were significantly decreased (FA: p-value = 0.01, Tract density: p-value = 0.05) after injury. The mean diffusivity (MD) was insignificantly increased compared to before the injury. Also, the results of UDS and pathology assessments corroborated that applying SCI and the establishment of the NLUTD model was completely successful. CONCLUSION: In the present study, we investigated the auxiliary role of tractography in detecting the spinal cord lesions in the novel established rabbit model of NLUTD. The introduced method of NLUTD induction was without the leg's neurological deficit, easily applicable, low-cost, and was accompanied by minimal surgical preparation and a satisfactory survival rate in comparison with other SCI animal models.

Application of iPSCs derived pancreatic ß-like cells using pancreatic bio-scaffold.

This study aimed toengineer a pancreatic tissue. Intact rat pancreases were successfully decellularized, and were reseeded with human-induced pluripotent stem cells using different 2D and 3D culture growth factors. The differentiation process was assessed for the presence of a pancreas-like tissue. The histology and SEM analysis revealed cell attachment in all samples, except for the Exp4, and the Flow-cytometry provided 87% viability for the differentiated cells. In Exp1, PDX1 with the positive expression of 2.87±0.06 was dramatically higher than Exp2 with a 2.44±0.06 reaction. NGN3-reactions were 8±0.1 and 6.6±0.2 in Exp1 and Exp2 at P < 0.05, respectively. C-peptide with the expression of 7.5±0.7 in Exp3 was almost equal to that in Exp1 and Exp2. Glucagon (5.1±1) and PDX1 (3.2±0.82) in Exp3 indicated no significant difference. The significant upregulations of pancreatic endocrine markers (PDX1 and NGN3), and the cell-specific glucose transporter (GLUT2) were observed in the differentiated IPCs in the 3D culture of Exp2 after 21 days. The highest insulin and C-peptide concentrations were observed in Exp2. In Exp3, insulin secretion in response to high glucose and 10 mM arginine was 42.43 ±6.34 µU/ml. A decellularized pancreas in the presence of hiPSCs and growth factors could be efficiently used as a natural scaffold.

Introduction of a modified single stage reconstruction technique of male penopubic epispadias.

OBJECTIVE: To represent the long-term outcomes of our modified single-stage technique for the reconstruction of isolated penopubic epispadias in male patients. PATIENTS AND METHODS: Data from 113 patients were obtained from bladder-exstrophy-epispadias database of our tertiary center. A total of seven boys with isolated penopubic epispadias with no prior history of surgery and any other anomaly underwent our modified surgical approach from February 1997 to September 2019. The mean ± SD age at surgery was 6.5 ± 2.4 years. Volitional voiding status and cosmetic appearance were evaluated at each follow-up interval. Postoperative follow-up was performed at quarterly intervals in the first year and once a year in subsequent years. RESULTS: The mean ± SD of follow-up was 8.5 ± 6 years. All boys who were incontinent achieved urinary control and the ability of normal transurethral micturition following the surgery. Four boys became completely dry, and the other three attained social dryness. Postoperative mean (SD) bladder capacity was significantly increased from 54.5 (11) to 124 (40.0) within 6 months, and to 194 (47.5) at 18 months after surgery. Dorsal curvature has been resolved in all cases, and no postoperative complications were noted except for surgical site infection in one patient treated with antibiotics and bilateral vesicourethral reflux resolved after injection of bulking agents. Four patients had normal erectile function and ejaculation, while the others have not reached puberty yet. Moreover, none of the patients developed urethrocutaneous fistula, stricture, or penile ischemia. CONCLUSION: The present findings suggest the safety and effectiveness of the combination of single-stage urethro-genitoplasty, bladder neck plication, and fat pad pedicled flap in management of boys with isolated penopubic epispadias that can lead to the achievement of urinary control, acceptable sexual function, and cosmetically satisfactory genitalia. Minimal morbidity, low complication rate, and promising outcomes are essential factors, supporting the notion of introducing this technique as a valid option for management of this entity.

Whole-organ decellularization of the human uterus and in vivo application of the bio-scaffolds in animal models.

PURPOSE: The aim of this investigation was to design a perfusion-based decellularization protocol to provide whole human uterine bio-scaffolds with preserved structural and componential characteristics and to investigate the in vivo properties of the decellularized tissues. METHODS: Eight human uteri, donated by brain-dead patients, were decellularized by perfusion of sodium dodecyl sulfate (SDS) through the uterine arteries using a peristaltic pump. The bio-scaffolds were evaluated and compared with native human uterus regarding histological, immunohistochemical, structural, and bio-mechanical properties, in addition to CT angiographies to examine the preservation of the vascular networks. Subsequently, we obtained acellular patches and implanted them on uterine defects of female Wistar rats to investigate the bio-compatibility and regenerative potential of the bio-scaffolds. Finally, we performed immunostaining to investigate the potential role of circulating stem cells in recellularization of the implanted bio-scaffolds. RESULTS: The outcomes of this investigation confirmed the efficacy of the proposed protocol to provide whole human uterine scaffolds with characteristics and extra-cellular matrix components similar to the native human uterus. Subsequent in vivo studies demonstrated the bio-compatibility and the regenerative potential of the scaffolds and suggested a signaling pathway as an underlying mechanism for the regenerative process. CONCLUSIONS: To the best of our knowledge, this investigation provides the first efficient perfusion-based decellularization protocol for the human uterus to obtain whole-organ scaffolds. The outcomes of this investigation could be employed in future human uterus tissue engineering studies which could ultimately result in the development of novel treatments for female infertile patients.

Detection of the residual concentration of sodium dodecyl sulfate in the decellularized whole rabbit kidney extracellular matrix.

To optimize rabbit kidney decellularization protocol, using sodium dodecyl sulfate (SDS) as a commonly used detergent, a methylene blue based assay was employed for detecting the minimum nontoxic SDS level for future cell seeding. The rabbit kidney tissues were decellularized with the perfusion-based method and underwent several investigations to determine the efficacy of decellularization in preserving the extracellular matrix (ECM) and cell removal. SDS detection was performed by incubating with methylene blue and subsequent extraction with chloroform. MTT (3-(4, 5-dimethylthiazol-2-yr)-2,5-diphenyltetrazolium bromide) assay and SDS release were also evaluated during the entire process. After the first washing cycle, SDS concentration was 0.036, in 500 mL of the washing liquid, which slowly decreased and reached to 0.009 % after at the end of seventh washing cycle. In the 9th cycle, SDS was gradually decreased and reached to 0.003 %. SDS was significantly released after one week of incubation which ceased after ten washing cycles. The results of MTT assay demonstrated that different cells exhibited various sensitivity levels when exposed to serial concentrations of SDS. Human embryonic kidney cells (HEK293) with 0.003 % threshold for cellular toxicity and 87.4 % cell viability were more resistant compared with mesenchymal stem cells with 0.001 % threshold and 85.4 % cell viability. Colorimetric assay with methylene blue is a straightforward and non-invasive method to detect residual SDS present in tissue and can also prevent ECM destruction after several washings for detergent removal from decellularized tissues.

Esophagus tissue engineering: from decellularization to in vivo recellularization in two sites.

To produce an esophageal scaffold with suitable features and evaluate the result of in vivo cell seeding after its implantation in the omentum and near its original anatomical position in the rat model. The esophagus of twelve rats were resected, cannulated, and decellularized via a peristaltic pump. After confirmation of decellularization and preservation of extracellular matrix, decellularized scaffolds were implanted either in the abdominal cavity (group I, n = 6) or cervical area (group II, n = 6). Histological evaluations were performed after 3 and 6 months of implantation. The results of histological evaluations, scanning electron microscopy, and the tensile test confirmed the maintenance of extracellular matrix and removal of all cellular constituents. At the time of biopsy, no evidence of inflammation was detected and the implanted scaffolds appeared normal. Histopathological evaluations of implanted tissues revealed that undifferentiated cells were seen in scaffolds of all follow-ups in both groups. Epithelial cell seeding was more advanced in biopsies of group II obtained after 6 months of operation and was accompanied by angiogenesis in surrounding adventitia. It seems that the implantation of scaffold near its original place may have an important role in further cell seeding. This method may be surpassing in comparison with traditional implantation techniques for perfecting esophageal transplantation.

An outlook on antigen-specific adoptive immunotherapy for viral infections with a focus on COVID-19.

Although not a standard-of-care yet, adoptive immunotherapeutic approaches have gradually earned a place within the list of antiviral therapies for some of fatal and hard-to-treat viral diseases. To maintain robust antiviral immunity and to effectively target the viral particles and virally-infected cells, immune cells capable of recognizing the viral antigens are required. While conventional vaccination can induce these cells in vivo; another option is to prime and generate antigen-specific immune cells ex vivo. This approach has been successfully trialed for virulent opportunistic viral infections after bone marrow transplantation. Amid the crisis of SARS-CoV2 pandemic, which has been followed by the success of certain early-authorized vaccines; some institutions and companies have explored the effects of viral-specific adoptive cell transfers (ACTs) in trials, as alternative treatments. Aimed at outlining a perspective on antigen-specific adoptive immunotherapy for viral infections, this review article specifically provides an appraisal of ACT-based studies/trials on SARS-CoV2 infection.

Comparing predictive values of carbohydrate antigen 19-9, neutrophil gelatinase-associated lipocalin, and kidney injury molecule-1 in 161 patients with ureteropelvic junction obstruction.

BACKGROUND: To evaluate and compare the efficacy of urinary carbohydrate antigen 19-9 (CA19-9), neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury molecule-1 (KIM-1) biomarkers as predictive factors to determine the surgery requirement in patients with ureteropelvic junction obstruction. METHODS: We obtained urine samples from 161 patients at diagnosis and evaluated their levels of the three biomarkers. The patients were under observation for 2 years; subsequently, they were divided into two groups based on their requirement of pyeloplasty. We determined the correlation between the urinary concentration of the biomarkers and surgical interventions, as well as the kidney function deterioration and sonography outcomes. RESULTS: The non-surgery group included 60 male and 22 female patients with mean age of 21 months. The surgery group comprised 58 boys and 21 girls with mean age of 26.9 months with no significant difference of age and gender between the two groups. The outcomes were indicative of higher efficacy of CA19-9 level with a sensitivity and specificity of 84.2% and 73.2% at the cutoff point of 59.09 U/ml. Also, a significant negative correlation was detected between the kidney function and the concentrations of CA19-9 and NGAL. CONCLUSIONS: Our evaluations demonstrate the higher efficacy of CA19-9 to predict the requirement of surgical intervention in comparison with the other biomarkers, as well as a significant correlation between kidney function deterioration and urinary CA19-9 and NGAL. The outcomes of this investigation could pave the way for more extensive clinical application of these urinary biomarkers, besides future research determining the association between markers and kidney fibrosis.

Lung Extracellular Matrix as a Platform for Lung Organ Bioengineering: Design and Development of Tissue Engineered Lung.

Since lung tissue is not able to be reconstructed after substantial injury, lung transplantation often is the only alternative for treatment. Antibiotic-resistant organisms that remain in donor lungs causing infection in the immunosuppressed recipient are among the complications following transplantation. Development of strategies for whole lung regeneration is a pleasing choice particularly in patients with end-stage lung diseases. Reconstruction of lung tissue in vitro for transplantation received increased attention which could deal with the shortage of donor organs. Recent advancements in the field of tissue engineering and regenerative medicine have paved the road for beneficial alternative therapies. Our group has extensive experience with regard to the structure of the lung tissue, which makes us to our decision to continue with the preparation of lung, with the aim of developing a new ECM scaffold. Herein, we aim to review the state-of-art and the tissue engineering and regenerative medicine technology highlighting the major achievements toward the production of a bioengineered lung obtained decellularization and recellularization techniques. We have strong hopes that recent developments in the engineering of lung will lead to similar breakthroughs in the engineering of distal lung components in the future.

The Most Ideal Pancreas Extracellular Matrix as a Platform for Pancreas Bioengineering: Decellularization/Recellularization Protocols.

Natural scaffold appears to have extensive functions in providing anchorage and structural requirements, as well as providing a structural support for cell adherence and cell interaction for further recellularization process. Specific methods used for decellularization process play an essential role in the efficacy of cell removal and successful preservation of ultrastructure and biomechanical properties of the tissue. Numerous scaffolding materials and fabrication techniques have been investigated for pancreatic tissue engineering. Techniques of casting, freeze drying, injection molding, and electrospinning have been also used to fabricate scaffolds. Herein, we aim to review the state-of-the-art and the tissue engineering and regenerative medicine technology highlighting the major achievements toward the production of a bioengineered pancreas obtained decellularization techniques and cell-on-scaffold technology.

The Renal Extracellular Matrix as a Supportive Scaffold for Kidney Tissue Engineering: Progress and Future Considerations.

During the past decades, diverse methods have been used toward renal tissue engineering in order to replace renal function. The goals of all these techniques included the recapitulation of renal filtration, re-absorptive, and secretary functions, and replacement of endocrine/metabolic activities. It is also imperative to develop a reliable, up scalable, and timely manufacturing process. Decellularization of the kidney with intact ECM is crucial for in-vivo compatibility and targeted clinical application. Contemporarily there is an increasing interest and research in the field of regenerative medicine including stem cell therapy and tissue bioengineering in search for new and reproducible sources of kidneys. In this chapter, we sought to determine the most effective method of renal decellularization and recellularization with emphasis on biologic composition and support of stem cell growth. Current barriers and limitations of bioengineered strategies will be also discussed, and strategies to overcome these are suggested.

Cardiac Extracellular Matrix as a Platform for Heart Organ Bioengineering: Design and Development of Tissue-Engineered Heart.

The field of tissue engineering and regenerative medicine is able to depict the mechanism of cardiac repair and development of cardiac function as well, in order to reveal findings to new therapeutic designs for clinical treatment. The foremost approach of this scientific field is the fabrication of scaffolds, which contain cells that can be used as cardiac grafts in the body, to have the preferred recovery. Cardiac tissue engineering has not been completely organized for routine clinical usages. Hence, engineering innovations hold promise to character research and treatment options in the years to come. Our group has extensive experience with regard to the structure of the heart, which makes us to our decision to continue with the preparation of heart, with the aim of developing a new ECM scaffold. Herein, we aim to assess the state-of-the-art fabrication methods, advances in decellularization and recellularization techniques. We also highlight the major achievements toward the production of a bioengineered heart obtained from decellularization and recellularization techniques.

Characterization Methods of Acellularized Tissue and Organs.

The extracellular matrix (ECM) of mammalian organs and tissues has been applied as a substitute scaffold to simplify the restoration and reconstruction of several tissues. Such scaffolds are prepared in various arrangements including sheets, powders, and hydrogels. One of the more applicable processes is using natural scaffolds, for this purpose discarded tissues or organs are naturally derived by processes that comprised decellularization of following tissues or organs. Protection of the complex structure and 3D (three dimensional) ultrastructure of the ECM is extremely necessary but it is predictable that all protocols of decellularization end in disruption of the architecture and potential loss of surface organization and configuration. Tissue decellularization with conservation of ECM bioactivity and integrity can be improved by providing well-designed protocols regarding the agents and decellularization techniques operated during processing. An overview of the characterization of decellularized scaffolds and the role of reagnets can validate the applied methods' efficacy.

Fetal Lung Tissue Engineering.

Lung transplantation may be considered as a final treatment option for diseases such as chronic lung disease, pulmonary hypertension, bronchopulmonary dysplasia, pulmonary fibrosis, and end-stage lung disease. The five-year survival rate of lung transplants is nearly 50%. Unfortunately, many patients will die before a suitable lung donor can be found. Importantly, the shortage of donor organs has been a significant problem in lung transplantation. The tissue engineering approach uses de- and recellularization of lung tissue to create functional lung substitutes to overcome donor lung limitations. Decellularization is hope for generating an intact ECM in the development of the engineered lung. The goal of decellularization is to prepare a suitable scaffold of lung tissue that contains an appropriate framework for the functionality of regenerated lung tissue. In this chapter, we aim to describe the decellularization protocols for lung tissue regenerative purposes.

Extracellular Matrix Scaffold Using Decellularized Cartilage for Hyaline Cartilage Regeneration.

The repair of osteochondral defects is among the top ten medical needs of humans in the 21st centuries with many countries facing rapidly aging population involved with osteoarthritis as a major contributor to global disease burden. Tissue engineering methods have offered new windows of hope to treat such disorders and disabilities. Regenerative approaches to cartilage injuries require careful replication of the complex microenvironment of the native tissue. The decellularized hyaline cartilage derived from human allografts or xenografts is potentially an ideal scaffold, simulating the mechanical and biochemical properties, as well as biological microarchitecture of the hyaline cartilage. There have been many attempts to regenerate clinically viable hyaline cartilage tissue using decellularized cartilage-derived extracellular matrix with stem cell technology. This chapter describes the reproducible methods for hyaline cartilage decellularization and recellularization. In addition, quality control and characterization requirements of the product at each step, as well as the clinical applications of final product have been discussed.