Adipose-derived stromal cell transplantation for treatment of stress urinary incontinence

Influence of background characteristics in responders of regenerative therapy by periurethral injection of adipose-derived regenerative cells for male stress urinary incontinence

OBJECTIVES

To determine if the male responders with post-prostatectomy incontinence in the ADRESU study, which is a clinical trial of regenerative therapy by periurethral injection of adipose-derived regenerative cells, are influenced by any background characteristics.

METHODS

Briefly, autologous adipose-derived regenerative cells isolated from abdominal adipose tissue and a mixture of adipose-derived regenerative cells with fat tissue were transurethrally injected into the rhabdosphincter and submucosal space of the urethra, respectively. Sixteen out of 43 patients (37.2%) responded to treatment (responders) and exhibited improvement in the urine leakage volume, defined as >50% reduction from baseline determined by the 24-hour pad test at 52 weeks of treatment (or last visit within 52 weeks). Background data such as age, body weight, method of prostatectomy, baseline frequency of leaks, number of leaks, number of pad changes, International Consultation on Incontinence Questionnaire-Short Form, King's Health Questionnaire, urodynamic urethral function including functional profile length and maximum urethral closure pressure, and abdominal leak point pressure were collected and compared between responders and nonresponders.

RESULTS

None of the background factors influenced improvement in the responders as compared with the nonresponders. However, a significant between-group difference in the rates of decrease in urine leakage volume was noted in patients of younger age (<70 years), compared with those of older age (≥70 years) from 2 to 26 weeks of treatment.

CONCLUSION

A greater decrease in urine leakage volume was noted in the younger patient group than in the older patient group.

Design of a single-arm clinical trial of regenerative therapy by periurethral injection of adipose-derived regenerative cells for male stress urinary incontinence in Japan: the ADRESU study protocol

BACKGROUND

Male stress urinary incontinence is a prevalent condition after radical prostatectomy. While the standard recommendation for the management of urine leakage is pelvic floor muscle training, its efficacy is still unsatisfactory. Therefore, we have focused on regenerative therapy, which consists of administering a periurethral injection of autologous regenerative cells from adipose tissue, separated using the Celution® system. Based on an interim data analysis of our exploratory study, we confirmed the efficacy and acceptable safety profile of this treatment. Accordingly, we began discussions with Japanese regulatory authorities regarding the development of this therapy in Japan. The Ministry of Health, Labour and Welfare suggested that we implement a clinical trial of a new medical device based on the Pharmaceutical Affaires Act in Japan. Next, we discussed the design of this investigator-initiated clinical trial (the ADRESU study) aimed at evaluating the efficacy and safety of this therapy, in a consultation meeting with the Pharmaceuticals and Medical Device Agency.

METHODS

The ADRESU study is an open-label, multi-center, single-arm study involving a total of 45 male stress urinary incontinence patients with mild-to-moderate urine leakage persisting more than 1 year after prostatectomy, in spite of behavioral and pharmacological therapies. The primary endpoint is the rate of patients at 52 weeks with improvement of urine leakage volume defined as a reduction from baseline greater than 50% by 24-h pad test. Our specific hypothesis is that the primary endpoint result will be higher than a pre-specified threshold of 10%.

DISCUSSION

The ADRESU study is the first clinical trial of regenerative treatment for stress urinary incontinence by adipose-derived regenerative cells using the Celution® system based on the Japanese Pharmaceutical Affaires Act. We will evaluate the efficacy and safety in this trial to provide an adequate basis for marketing approval with the final objective of making this novel therapy widely available for Japanese patients.

TRIAL REGISTRATION

This trial was registered at the University Hospital Medical information Network Clinical Trial Registry (UMIN-CTR Unique ID: UMIN000017901 ; Registered July 1, 2015) and at ClinicalTrials.gov (ClinicalTrials.gov Identifier: NCT02529865 ; Registered August 18, 2015).

Tissue-engineered sling with adipose-derived stem cells under static mechanical strain

The implantation of a suburethral sling is an important treatment for stress urinary incontinence (SUI). However, the slings used current have a number of inherent limitations, such as tissue rejection and infection. The present study investigated the potential of engineering sling tissue in vitro using adipose-derived stem cells (ADSCs). The ADSCs were obtained from Sprague-Dawley rats and were characterized in vitro. The ADSCs were seeded on polyglycolic acid (PGA) fibers that formed a scaffold with a shape mimicking a sling complex. The results demonstrated that following in vitro culture for 12 weeks under static strain, neo-sling tissue could be generated using ADSCs. With increasing culture time, the engineered neo-sling tissue exhibited a significant improvement in biomechanical properties, including maximal load and Young's modulus (P<0.05), and the tissue and collagen structures matured. Furthermore, differentiated ADSCs cultured under static strain were maintained their myoblast phenotype within the PGA scaffolds. These results indicate that ADSCs may serve as a novel cell source for tissue sling engineering and could improve treatment for patients with SUI.

Precise injection of human mesenchymal stromal cells in the urethral sphincter complex of Göttingen minipigs without unspecific bulking effects

AIM

To investigate if injection of cells in the urethral sphincter complex causes unspecific bulking effects.

METHODS

Human mesenchymal stromal cells were isolated, expanded, and characterized. For transurethral injection, cells were labeled with the fluorescent dye PKH26 and in magnetic resonance imaging associated experiments with superparamagnetic particles. Aliquots of cells in 250 µL solvent were injected under vision in the urethral sphincter of immuno-suppressed Göttingen minipigs. Sphincteric closure pressure was recorded by standard and high-definition urethral pressure profilometry prior to and after cell injection. The animals were sacrificed after surgery or after 3 weeks, 3, 6, or 12 months of follow-up. The localisation of the injected cells was explored by histochemistry. Sham-treated animals served as controls.

RESULTS

PKH26-labeled cells survive injections in sphincter tissue samples by Williams cystoscopic injection needle well. In our animal study, the cellular depots were detected in the submucosa or in deeper zones of the sphincter, depending of the length of the injection needle (4-8 mm). Adverse effects associated with injection of cells or solvent such as a noteworthy bleeding, incontinence, or obstruction, were not recorded (n = 96 minipigs). However, a transient infiltration of macrophages was detected 3 weeks after cell injection. Changes in the urethral pressure profiles were not observed in cell-treated (n = 72) compared to sham-treated animals (n = 24).

CONCLUSIONS

Injection of small aliquots of cells to investigate cell therapies in minipigs is a feasible and safe procedure, and it does not bias the intrinsic urethral wall pressure.

Small activating RNA induces myogenic differentiation of rat adipose-derived stem cells by upregulating MyoD

PURPOSE

RNA activation (RNAa) is a mechanism of gene activation triggered by promoter-targeted small double stranded RNAs (dsRNAs), also known as small activating RNAs (saRNAs). Myogenic regulatory factor MyoD is regarded as the master activator of myogenic differentiation cascade by binding to enhancer of muscle specific genes. Stress urinary incontinence (SUI) is a condition primarily resulted from urethral sphincter deficiency. It is thus expected that by promoting differentiation of adipose-derived stem cells (ADSCs) into myoblasts by activating MyoD gene through RNAa may offer benefits to SUI.

MATERIALS AND METHODS

Rats ADSCs were isolated, proliferated in vitro, and identified by flow cytometry. Purified ADSCs were then transfected with a MyoD saRNA or control transfected. Real-time polymerase chain reaction (RT-PCR) and western blotting were used to detect MyoD mRNA and protein expression, respectively. Immunocytochemical staining was applied to determine the expression of desmin protein in transfected cells. Cell viability was measured by using CellTiter 96R AQueous One Solution Cell Proliferation Assay kit.

RESULTS

Transfection of a MyoD saRNA (dsMyoD) into ADSCs significantly induced the expression of MyoD at both the mRNA and protein levels, and inhibited cell proliferation. Desmin protein expression was detected in dsMyoD treated ADSCs 2 weeks later.

CONCLUSION

Our findings show that RNAa mediated overexpression of MyoD can promote transdifferentiation of ADSCs into myoblasts and may help treat stress urinary incontinence (SUI)-a condition primarily resulted from urethral sphincter deficiency.

Adipose-derived stem cells seeded on polyglycolic acid for the treatment of stress urinary incontinence

PURPOSE

To evaluate the effect and possible mechanism of suburethral tissue-engineered sling in an animal model of stress urinary incontinence (SUI).

METHODS

Adipose-derived stem cells (ADSCs) were obtained from the adipose tissues of rats. The differentiation potential, proliferation, and viability of rat ADSCs were evaluated after infecting these cells with a lentiviral vector-encoding green fluorescent protein (GFP). Next, GFP transfected ADSCs were seeded on polyglycolic acid (PGA) fibers to construct the tissue-engineered sling with the induction of 5-azacytidine (5-Aza). Afterward, the tissue-engineered slings were transplanted into a rat model of SUI that was established by vaginal balloon dilatation method and bilateral ovariectomy. Histology and the leak point pressure measurements were performed at 2 months after tissue-engineered sling implantation.

RESULTS

The ADSCs were found to be efficiently transfected with GFP, without any effects on proliferation, cell cycle and multi-differentiation potential. After been seeded on PGA fibers, ADSCs formed tissue-engineered slings in 4 weeks of induction culture. Two months after implantation, the mean leak point pressure (LPP) was significantly increased in sling-treated rats compared with the balloon-injured ovariectomized rats. Immunofluorescence assay showed that some of the GFP expressing cells stained positive for muscle-specific markers.

CONCLUSIONS

The newly suburethral tissue-engineered sling restores LPP in the rat model of SUI, which could be an effective treatment in future SUI therapy.

Stem cell applications for pathologies of the urinary bladder

New stem cell based therapies are undergoing intense research and are widely investigated in clinical fields including the urinary system. The urinary bladder performs critical complex functions that rely on its highly coordinated anatomical composition and multiplex of regulatory mechanisms. Bladder pathologies resulting in severe dysfunction are common clinical encounter and often cause significant impairment of patient’s quality of life. Current surgical and medical interventions to correct urinary dysfunction or to replace an absent or defective bladder are sub-optimal and are associated with notable complications. As a result, stem cell based therapies for the urinary bladder are hoped to offer new venues that could make up for limitations of existing therapies. In this article, we review research efforts that describe the use of different types of stem cells in bladder reconstruction, urinary incontinence and retention disorders. In particular, stress urinary incontinence has been a popular target for stem cell based therapies in reported clinical trials. Furthermore, we discuss the relevance of the cancer stem cell hypothesis to the development of bladder cancer. A key subject that should not be overlooked is the safety and quality of stem cell based therapies introduced to human subjects either in a research or a clinical context.

Prospects of stem cell treatment in benign urological diseases

Stem cells (SCs) are undifferentiated cells that are capable of self-renewal and differentiation and that therefore contribute to the renewal and repair of tissues. Their capacity for division, differentiation, and tissue regeneration is highly dependent on the surrounding environment. Several preclinical and clinical studies have utilized SCs in urological disorders. In this article, we review the current status of SC use in benign urological diseases (erectile dysfunction, Peyronie disease, infertility, and urinary incontinence), and we summarize the results of the preclinical and clinical trials that have been conducted.

Stress urinary incontinence animal models as a tool to study cell-based regenerative therapies targeting the urethral sphincter

Urinary incontinence (UI) is a major health problem causing a significant social and economic impact affecting more than 200million people (women and men) worldwide. Over the past few years researchers have been investigating cell therapy as a promising approach for the treatment of stress urinary incontinence (SUI) since such an approach may improve the function of a weakened sphincter. Currently, a diverse collection of SUI animal models is available. We describe the features of the different models of SUI/urethral dysfunction and the pros and cons of these animal models in regard to cell therapy applications. We also discuss different cell therapy approaches and cell types tested in preclinical animal models. Finally, we propose new research approaches and perspectives to ensure the use of cellular therapy becomes a real treatment option for SUI.

The role of CXCL12 and CCL7 chemokines in immune regulation, embryonic development, and tissue regeneration

Chemotactic factors direct the migration of immune cells, multipotent stem cells, and progenitor cells under physiologic and pathologic conditions. Chemokine ligand 12 and chemokine ligand 7 have been identified and investigated in multiple studies for their role in cellular trafficking in the setting of tissue regeneration. Recent early phase clinical trials have suggested that these molecules may lead to clinical benefit in patients with chronic disease. Importantly, these two proteins may play additional significant roles in directing the migration of multipotent cells, such as mesenchymal stem cells and hematopoietic progenitor cells. This article reviews the functions of these two chemokines, focusing on recruitment to sites of injury, immune function modulation, and contributions to embryonic development. Additional research would provide valuable insight into the potential clinical application of these two proteins in stem cell therapy.

Autologous adipose stem cells in treatment of female stress urinary incontinence: results of a pilot study

The purpose of our study was to find out whether transurethral injections of autologous adipose stem cells (ASCs) are an effective and a safe treatment for female stress urinary incontinence (SUI). We treated five SUI patients with ASCs combined with bovine collagen gel and saline. Prior to the treatment, the ASCs were isolated from subcutaneous fat and expanded for 3 weeks in a good manufacturing practice-level laboratory. The mixture of ASCs and collagen was injected transurethrally via cystoscope. Additionally, viability, multipotency, and surface marker profile of ASCs were analyzed in vitro. We followed up with patients 3, 6, and 12 months after the injections. The primary endpoint was a cough test to measure objectively the effect of the treatment. Validated questionnaires were used to determine the subjective cure rate. After 6 months, 1 of 5 patients displayed a negative cough test with full bladder filled with 500 ml of saline. At 1 year, the cough test was negative with three patients; two of them were satisfied with the treatment and did not wish further treatment for SUI. Validated questionnaires showed some subjective improvement in all five patients. This is the first study describing the use of autologous ASCs in combination with collagen gel for female SUI treatments. Thus far, the treatment with autologous ASCs has proven safe and well tolerated. However, the feasibility and efficacy of the treatment were not optimal; therefore, additional research is needed to develop SUI injection therapies.

Epithelial-differentiated adipose-derived stem cells seeded bladder acellular matrix grafts for urethral reconstruction: an animal model

The limited amount of available epithelial tissue is considered a main cause of the high rate of urethral reconstruction failures. The aim of this study was to investigate whether epithelial-differentiated rabbit adipose-derived stem cells (Epith-rASCs) could play a role of epithelium in vivo functionally and be a potential substitute of urothelium. Substitution urethroplasty was performed to repair an anterior urethral defect in male New Zealand rabbits using Epith-rASCs seeded bladder acellular matrix grafts (BAMGs) after 5-bromo-2'-deoxyuridine (BrdU) labeling, based on the in vitro epithelial induction system we previously described. Urethroplasty with cell-free BAMGs and with undifferentiated rASCs (Und-rASCs) seeded BAMGs were performed as controls. After surgery, a notable amelioration of graft contracture and recovery of urethral continuity were observed in the Epith-rASCs/BAMG group by retrograde urethrograms and macroscopic inspection. Immunofluorescence revealed that the BrdU-labeled Epith-rASCs/Und-rASCs colocalized with cytokeratin 13 or myosin. Consistent with the results of western blotting, at early postimplantation stage, the continuous epithelial layer with local multilayered structure was observed in the Epith-rASCs/BAMG group, whereas no significant growth and local monolayer growth profile of epithelial cells were observed in the BAMG and Und-rASCs/BAMG group, respectively. The results showed that Epith-rASCs could serve as a potential substitute of urothelium for urethral tissue engineering and be available to prevent lumen contracture and subsequent complications including recurrent stricture.

Regenerative treatment of male stress urinary incontinence by periurethral injection of autologous adipose-derived regenerative cells: 1-year outcomes in 11 patients

OBJECTIVES

To assess the efficacy and safety of a novel cell therapy for male stress urinary incontinence consisting of periurethral injection of autologous adipose-derived regenerative cells, and to determine the 1-year outcomes.

METHODS

A total of 11 male patients with persistent stress urinary incontinence after prostate surgery were included in the study. The Celution system was used to isolate adipose-derived regenerative cells from abdominal adipose tissue obtained by liposuction. Subsequently, these regenerative cells, and a mixture of regenerative cells and adipose tissue were transurethrally injected into the rhabdosphincter and submucosal space of the urethra, respectively. The 1-year outcomes were assessed using a 24-h pad test, a validated patient questionnaire, urethral pressure profile, transrectal ultrasonography and magnetic resonance imaging.

RESULTS

Stress urinary incontinence improved progressively in eight patients during the 1-year follow up, as determined by a 59.8% decrease in the leakage volume in the 24-h pad test, decreased frequency and amount of incontinence, and improved quality of life. One patient achieved total continence. The mean maximum urethral closing pressure and functional profile length increased from 35.5 to 44.7 cmH₂O, and from 20.4 to 26.0 mm, respectively. Magnetic resonance imaging showed the sustained presence of the injected adipose tissue, and enhanced ultrasonography showed a progressive increase in blood flow to the injected area in all patients. No significant adverse events were observed peri- or postoperatively.

CONCLUSION

Periurethral injection of autologous adipose-derived regenerative cells might represent a safe and feasible treatment modality for male stress urinary incontinence.

Tissue engineering of urinary bladder - current state of art and future perspectives

Introduction

Tissue engineering and biomaterials science currently offer the technology needed to replace the urinary tract wall. This review addresses current achievements and barriers for the regeneration of the urinary blad- der based on tissue engineering methods.

Materials and methods

Medline was search for urinary bladder tissue engineering regenerative medicine and stem cells.

Results

Numerous studies to develop a substitute for the native urinary bladder wall us- ing the tissue engineering approach are ongoing. Stem cells combined with biomaterials open new treatment methods, including even de novo urinary bladder construction. However, there are still many issues before advances in tissue engineering can be introduced for clinical application.

Conclusions

Before tissue engineering techniques could be recognize as effective and safe for patients, more research stud- ies performed on large animal models and with long follow–up are needed to carry on in the future.

Harvest site influences the growth properties of adipose derived stem cells

The therapeutic potential of adult stem cells may become a relevant option in clinical care in the future. In hand and plastic surgery, cell therapy might be used to enhance nerve regeneration and help surgeons and clinicians to repair debilitating nerve injuries. Adipose-derived stem cells (ASCs) are found in abundant quantities and can be harvested with a low morbidity. In order to define the optimal fat harvest location and detect any potential differences in ASC proliferation properties, we compared biopsies from different anatomical sites (inguinal, flank, pericardiac, omentum, neck) in Sprague-Dawley rats. ASCs were expanded from each biopsy and a proliferation assay using different mitogenic factors, basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF) was performed. Our results show that when compared with the pericardiac region, cells isolated from the inguinal, flank, omental and neck regions grow significantly better in growth medium alone. bFGF significantly enhanced the growth rate of ASCs isolated from all regions except the omentum. PDGF had minimal effect on ASC proliferation rate but increases the growth of ASCs from the neck region. Analysis of all the data suggests that ASCs from the neck region may be the ideal stem cell sources for tissue engineering approaches for the regeneration of nervous tissue.

Adipose-Derived Stem Cells in Tissue Regeneration: A Review

In 2001, researchers at the University of California, Los Angeles, described the isolation of a new population of adult stem cells from liposuctioned adipose tissue. These stem cells, now known as adipose-derived stem cells or ADSCs, have gone on to become one of the most popular adult stem cells populations in the fields of stem cell research and regenerative medicine. As of today, thousands of research and clinical articles have been published using ASCs, describing their possible pluripotency in vitro, their uses in regenerative animal models, and their application to the clinic. This paper outlines the progress made in the ASC field since their initial description in 2001, describing their mesodermal, ectodermal, and endodermal potentials both in vitro and in vivo, their use in mediating inflammation and vascularization during tissue regeneration, and their potential for reprogramming into induced pluripotent cells.

Development of stem cell therapy for stress urinary incontinence

PURPOSE OF REVIEW

In recent years, stem cell therapy has been investigated as a promising approach for the treatment of stress urinary incontinence (SUI). This article reviews the biology of stem cells and their applications as a cell-based treatment for SUI. The current status and future direction of this forefront research in urinary incontinence are also examined.

RECENT FINDINGS

During the past decade, adult stem cells have been studied as a potential cell-based approach for the treatment of SUI. The results of current preclinical and clinical studies are presented. These studies demonstrated the improvement in histologic and functional outcomes with stem cell therapies for SUI. Adult stem cells may augment sphincter regeneration and also release trophic factors, promoting vessel and nerve integration into the generated tissues. So far, the findings of the clinical trials are less impressive than the results obtained with animal studies.

SUMMARY

Although stem cell therapy holds much promise for SUI, the clinical applications in patients have been slow to materialize. This challenge, together with the currently limited data on basic science studies and clinical trials, will undoubtedly stimulate new investigations in the near future.

Stem cells in gynecology

Stem cell based therapies hold promise for the obstetrician and gynecologist. This article reviews the history of stem cells and some of their current applications in gynecology. Currently, mesenchymal and muscle-derived stem cells are being explored for the treatment of urinary and anal incontinence. Potential stem cell treatments include fistula repair, vaginal tissue engineering, and graft material enhancement. Published animal and human pilot studies demonstrate improved histologic and functional outcomes in those receiving stem cells. Transplanted cells may improve function by local engraftment, trophic factors, or modulation of inflammation. Further clinical and safety studies are needed before clinical application.

Tissue engineering for the oncologic urinary bladder

Urinary diversion after radical cystectomy in patients with bladder cancer normally takes the form of an ileal conduit or neobladder. However, such diversions are associated with a number of complications including increased risk of infection. A plausible alternative is the construction of a neobladder (or bladder tissue) in vitro using autologous cells harvested from the patient. Biomaterials can be used as a scaffold for naturally occurring regenerative stem cells to latch onto to regrow the bladder smooth muscle and epithelium. Such engineered tissues show great promise in urologic tissue regeneration, but are faced with a number of challenges. For example, the differentiation mesenchymal stem cells from various sources can be difficult and the smooth muscle cells formed do not precisely mimic the natural cells.

Periurethral injection of autologous adipose-derived regenerative cells for the treatment of male stress urinary incontinence: Report of three initial cases

OBJECTIVES

To report a novel cell therapy using autologous adipose tissue-derived regenerative cells for male stress urinary incontinence caused by urethral sphincteric deficiency, and the outcomes in the initial cases undergoing periurethral injection of adipose tissue-derived regenerative cells.

METHODS

Three patients with moderate stress incontinence after radical prostatectomy and holmium laser enucleation of the prostate were enrolled. Adipose tissue-derived regenerative cells were isolated from the abdominal adipose tissue by using the Celution system. Subsequently, the isolated adipose tissue-derived regenerative cells, and a mixture of adipose tissue-derived regenerative cells and adipose tissue were transurethrally injected into the rhabdosphincter and submucosal space of the urethra, respectively. Short-term outcomes during a 6-month follow up were assessed by a 24-h pad test, a validated patient questionnaire, urethral pressure profile, transrectal ultrasonography and magnetic resonance imaging.

RESULTS

Urinary incontinence progressively improved after 2 weeks of injection up to 6 months in terms of decreased leakage volume, decreased frequency and amount of incontinence, and improved quality of life. Both maximum urethral closing pressure and functional profile length increased. Magnetic resonance imaging suggested a sustained presence of the injected adipose tissue. Enhanced ultrasonography showed a progressive increase in the blood flow to the injected area. No significant adverse events were observed peri- and postoperatively.

CONCLUSION

These preliminary findings suggest that periurethral injection of the autologous adipose tissue-derived regenerative cells is a safe and feasible treatment modality for male stress urinary incontinence.

Autologous Bone Marrow-Derived Cells Regenerate Urethral Sphincters

Regenerative medicine based on tissue engineering and/or stem cell therapy techniques has the potential to improve irreversibly damaged tissues. Surgical injury to the lower urinary tract can occur as a result of radical prostatectomy or bladder neck surgery. Regeneration of urethral sphincters could be an effective treatment for post-surgical intrinsic sphincter deficiency (ISD)-related urinary incontinence. The replacement, enhancement, and/or recovery the urethral sphincter striated and smooth muscles could increase urethral closure pressure to help patients regain continence. Stem cells from muscle-derived satellite or adipose-derived mesenchymal cells provide temporary improvement in urethral closure pressure but do not reconstruct the muscle layer structures. Our strategy to accomplish regeneration of urethral sphincters is the utilization of autologous bone marrow-derived cells. We have developed a freeze injury model of ISD in rabbits. Freezing of the urinary sphincter causes loss of the majority of striated and smooth muscle cells, and causes a significant decrease in leak point pressure. In this review, we show that the autologous bone marrow-derived cells implanted within the freeze-injured sphincters differentiate into striated or smooth muscle cells. These cells then develop to reconstitute muscle layer structures within the sphincter. Furthermore, the leak point pressure of cell-implanted rabbits is significantly higher than that of cell-free injected controls. We conclude that implantation of autologous bone marrow-derived cells could be an effective treatment for human post-surgical ISD-related urinary incontinence.

Stem cell therapy for stress urinary incontinence: a critical review

Stress urinary incontinence (SUI) is a prevailing health problem that severely impacts quality of life. Because SUI is mainly due to urethral sphincter deficiency, several preclinical and clinical trials have investigated whether transplantation of patient's own skeletal muscle-derived cells (SkMDCs) can restore the sphincter musculature. The specific cell type of SkMDCs has been described as myoblasts, satellite cells, muscle progenitor cells, or muscle-derived stem cells, and thus may vary from study to study. In more recent years, other stem cell (SC) types have also been tested, including those from the bone marrow, umbilical cord blood, and adipose tissue. These studies were mostly preclinical and utilized rat SUI models that were established predominantly by pudendal or sciatic nerve injury. Less frequently used animal models were sphincter injury and vaginal distension. While transurethral injection of SCs was employed almost exclusively in clinical trials, periurethral injection was used in all preclinical trials. Intravenous injection was also used in one preclinical study. Functional assessment of therapeutic efficacy in preclinical studies has relied almost exclusively on leak point pressure measurement. Histological assessment examined the sphincter muscle content, existence of transplanted SCs, and possible differentiation of these SCs. While all of these studies reported favorable functional and histological outcomes, there are questions about the validity of the animal model and claims of multilineage differentiation. In any event, SC transplantation appears to be a promising treatment for SUI.