No abstract available.
Printing, Three-Dimensional* ; Regenerative Medicine* ; Tissue Engineering*

The concept of cell transplantation using tissue engineering techniques has provided numerous possibilities in the area of urologic tissue reconstruction. Tissue engineering applications in the genitourinary tract system have been investigated in almost every tissue in order to improve, restore and replace existing tissue function. Although most reconstructive efforts still remain in the experimental stage, several technologies have been transferred to the bedside with satisfactory outcome. In this article, we describe tissue engineering approaches attempted in the genitourinary system for reconstruction.
Animal ; Biomedical Engineering* ; Bladder ; Fetus ; Gene Therapy/methods ; Genitalia ; Human ; Kidney ; Ureter ; Urethra ; Urogenital System*

The field of tissue engineering has made steady progress in translating various tissue applications. Although the classical tissue engineering strategy, which involves the use of culture-expanded cells and scaffolds to produce a tissue construct for implantation, has been validated, this approach involves extensive cell expansion steps, requiring a lot of time and laborious effort before implantation. To bypass this ex vivo process, a new approach has been introduced. In situ tissue regeneration utilizes the body's own regenerating capacity by mobilizing host endogenous stem cells or tissue-specific progenitor cells to the site of injury. This approach relies on development of a target-specific biomaterial scaffolding system that can effectively control the host microenvironment and mobilize host stem/progenitor cells to target tissues. An appropriate microenvironment provided by implanted scaffolds would facilitate recruitment of host cells that can be guided to regenerating structural and functional tissues.
Animals ; Guided Tissue Regeneration/*methods ; Humans ; Stem Cell Transplantation/*methods ; Stem Cells/*cytology/metabolism ; Tissue Engineering/methods ; Tissue Scaffolds

Neurogenic bladder is a general term encompassing various neurologic dysfunctions of the bladder and the external urethral sphincter. These can be caused by damage or disease. Therapeutic management options can be conservative, minimally invasive, or surgical. The current standard for surgical management is bladder augmentation using intestinal segments. However, because intestinal tissue possesses different functional characteristics than bladder tissue, numerous complications can ensue, including excess mucus production, urinary stone formation, and malignancy. As a result, investigators have sought after alternative solutions. Tissue engineering is a scientific field that uses combinations of cells and biomaterials to encourage regeneration of new, healthy tissue and offers an alternative approach for the replacement of lost or deficient organs, including the bladder. Promising results using tissue-engineered bladder have already been obtained in children with neurogenic bladder caused by myelomeningocele. Human clinical trials, governed by the Food and Drug Administration, are ongoing in the United States in both children and adults to further evaluate the safety and efficacy of this technology. This review will introduce the principles of tissue engineering and discuss how it can be used to treat refractory cases of neurogenic bladder.
Adult ; Biocompatible Materials ; Child ; Humans ; Meningomyelocele ; Mucus ; Neurologic Manifestations ; Regeneration ; Regenerative Medicine ; Research Personnel ; Tissue Engineering ; United States ; United States Food and Drug Administration ; Urethra ; Urinary Bladder ; Urinary Bladder, Neurogenic ; Urinary Calculi

The prevalence of renal disease continues to increase worldwide. When normal kidney is injured, the damaged renal tissue undergoes pathological and physiological events that lead to acute and chronic kidney diseases, which frequently progress to end stage renal failure. Current treatment of these renal pathologies includes dialysis, which is incapable of restoring full renal function. To address this issue, cell-based therapy has become a potential therapeutic option to treat renal pathologies. Recent development in cell therapy has demonstrated promising therapeutic outcomes, in terms of restoration of renal structure and function impaired by renal disease. This review focuses on the cell therapy approaches for the treatment of kidney diseases, including various cell sources used, as well recent advances made in preclinical and clinical studies.
Cell- and Tissue-Based Therapy/*methods ; Fetal Stem Cells/transplantation ; Humans ; Kidney/cytology ; Kidney Diseases/*therapy ; Pluripotent Stem Cells/transplantation ; Stem Cell Transplantation/methods

Urinary incontinence has become a societal problem that affects millions of people worldwide. Although numerous therapeutic modalities are available, none has been shown to be entirely satisfactory. Consequently, cell-based approaches using regenerative medicine technology have emerged as a potential solution that would provide a means of correcting anatomical deficiencies and restoring normal function. As such, numerous cell-based investigations have been performed to develop systems that are focused on addressing clinical needs. While most of these attempts remain in the experimental stages, several clinical trials are being designed or are in progress. This article provides an overview of the cell-based approaches that utilize various cell sources to develop effective treatment modalities for urinary incontinence.
Regenerative Medicine ; Tissue Therapy ; Urinary Incontinence

Patients with erectile dysfunction (ED) often lose self-esteem, leading to severe psychological impairment. Although many forms of ED can be corrected with currently available therapeutic measures, several types of ED and its associated conditions may not be readily treated. Recently, the concept of cell transplantation has been applied to address ED with the goal of restoring normal anatomical tissue configuration and erectile function. This article provides an overview of the fundamental principles of these cell-based approaches and presents a framework that can be used to interpret current and future studies as well as to encourage further research into cell-based therapies.
Cell Transplantation ; Erectile Dysfunction ; Humans ; Male ; Regenerative Medicine ; Tissue Therapy ; Transplants

Kidney diseases including acute kidney injury and chronic kidney disease are among the largest health issues worldwide. Dialysis and kidney transplantation can replace a significant portion of renal function, however these treatments still have limitations. To overcome these shortcomings, a variety of innovative efforts have been introduced, including cell-based therapies. During the past decades, advances have been made in the stem cell and developmental biology, and tissue engineering. As part of such efforts, studies on renal cell therapy and artificial kidney developments have been conducted, and multiple therapeutic interventions have shown promise in the pre-clinical and clinical settings. More recently, therapeutic cell-secreting secretomes have emerged as a potential alternative to cell-based approaches. This approach involves the use of renotropic factors, such as growth factors and cytokines, that are produced by cells and these factors have shown effectiveness in facilitating kidney function recovery. This review focuses on the renotropic functions of bioactive compounds that provide protective and regenerative effects for kidney tissue repair, based on the available data in the literature.
Acute Kidney Injury ; Cell- and Tissue-Based Therapy ; Cytokines ; Developmental Biology ; Dialysis ; Intercellular Signaling Peptides and Proteins ; Kidney ; Kidney Diseases ; Kidney Transplantation ; Kidneys, Artificial ; Recovery of Function ; Regenerative Medicine ; Renal Insufficiency ; Renal Insufficiency, Chronic ; Stem Cells ; Tissue Engineering

Novel therapies resulting from regenerative medicine and tissue engineering technology may offer new hope for patients with injuries, end-stage organ failure, or other clinical issues. Currently, patients with diseased and injured organs are often treated with transplanted organs. However, there is a shortage of donor organs that is worsening yearly as the population ages and as the number of new cases of organ failure increases. Scientists in the field of regenerative medicine and tissue engineering are now applying the principles of cell transplantation, material science, and bioengineering to construct biological substitutes that can restore and maintain normal function in diseased and injured tissues. In addition, the stem cell field is a rapidly advancing part of regenerative medicine, and new discoveries in this field create new options for this type of therapy. For example, new types of stem cells, such as amniotic fluid and placental stem cells that can circumvent the ethical issues associated with embryonic stem cells, have been discovered. The process of therapeutic cloning and the creation of induced pluripotent cells provide still other potential sources of stem cells for cell-based tissue engineering applications. Although stem cells are still in the research phase, some therapies arising from tissue engineering endeavors that make use of autologous, adult cells have already entered the clinical setting, indicating that regenerative medicine holds much promise for the future.
Adult ; Amniotic Fluid ; Biocompatible Materials ; Bioengineering ; Cell Transplantation ; Clone Cells ; Cloning, Organism ; Embryonic Stem Cells ; Female ; Humans ; Regenerative Medicine ; Stem Cells ; Tissue Donors ; Tissue Engineering ; Transplants

Engineering three-dimensional (3D) implantable tissue constructs is a promising strategy for replacing damaged or diseased tissues and organs with functional replacements. However, the efficient vascularization of new 3D organs is a major scientific and technical challenge since large tissue constructs or organs require a constant blood supply to survive in vivo. Current approaches to solving this problem generally fall into the following three major categories: (a) cell-based, (b) angiogenic factor-based, and (c) scaffold-based. In this review, we summarize state-of-the-art technologies that are used to develop complex, stable, and functional vasculature for engineered 3D tissue constructs and organs; additionally, we have suggested directions for future research.
Bioengineering ; Tissue Scaffolds