Human amniotic fluid stem cell injection therapy for urethral sphincter regeneration in an animal model

Abstract

BackgroundStem cell injection therapies have been proposed to overcome the limited efficacy and adverse reactions of bulking agents. However, most have significant limitations, including painful procurement, requirement for anesthesia, donor site infection and a frequently low cell yield. Recently, human amniotic fluid stem cells (hAFSCs) have been proposed as an ideal cell therapy source. In this study, we investigated whether periurethral injection of hAFSCs can restore urethral sphincter competency in a mouse model.MethodsAmniotic fluids were collected and harvested cells were analyzed for stem cell characteristics and in vitro myogenic differentiation potency. Mice underwent bilateral pudendal nerve transection to generate a stress urinary incontinence (SUI) model and received either periurethral injection of hAFSCs, periurethral injection of Plasma-Lyte (control group), or underwent a sham (normal control group).For in vivo cell tracking, cells were labeled with silica-coated magnetic nanoparticles containing rhodamine B isothiocyanate (MNPs@SiO2 (RITC)) and were injected into the urethral sphincter region (n = 9). Signals were detected by optical imaging. Leak point pressure and closing pressure were recorded serially after injection.Tumorigenicity of hAFSCs was evaluated by implanting hAFSCs into the subcapsular space of the kidney, followed two weeks later by retrieval and histologic analysis.ResultsFlow activated cell sorting showed that hAFSCs expressed mesenchymal stem cell (MSC) markers, but no hematopoietic stem cell markers. Induction of myogenic differentiation in the hAFSCs resulted in expression of PAX7 and MYOD at Day 3, and DYSTROPHIN at Day 7. The nanoparticle-labeled hAFSCs could be tracked in vivo with optical imaging for up to 10 days after injection. Four weeks after injection, the mean LPP and CP were significantly increased in the hAFSC-injected group compared with the control group. Nerve regeneration and neuromuscular junction formation of injected hAFSCs in vivo was confirmed with expression of neuronal markers and acetylcholine receptor. Injection of hAFSCs caused no in vivo host CD8 lymphocyte aggregation or tumor formation.ConclusionshAFSCs displayed MSC characteristics and could differentiate into cells of myogenic lineage. Periurethral injection of hAFSCs into an SUI animal model restored the urethral sphincter to apparently normal histology and function, in absence of immunogenicity and tumorigenicity.

Counteracting bone fragility with human amniotic mesenchymal stem cells

“…AFSCs are attractive candidates for cell therapy because they are easily accessible during pregnancy from the surplus of amniocentesis samples and can be used without ethical restriction9101112. They also have a high expansion potential, are non-tumorigenic, tolerogenic, anti-inflammatory and are small enough to pass through capillary beds to reach distant sites of action13141516. Their immunological properties make it possible to use them as universal allogeneic donor13141516.…”

“…They also have a high expansion potential, are non-tumorigenic, tolerogenic, anti-inflammatory and are small enough to pass through capillary beds to reach distant sites of action13141516. Their immunological properties make it possible to use them as universal allogeneic donor13141516. Compared to their adult counterparts, fetal MSCs have longer telomeres, have accumulated fewer genetic mutations and are easier to reprogram to pluripotency4.…”

The Dose-Effect Safety Profile of Skeletal Muscle Precursor Cell Therapy in a Dog Model of Intrinsic Urinary Sphincter Deficiency

“…Several different cell types have been used in preclinical studies to test their ability to restore urinary sphincter function [11][12][13][14][15][16]. The most commonly used in clinical studies have been skMPCs [16,18,19].…”

“…The cell types considered for use include bone marrow mesenchymal cells [11], adiposederived stem cells [12], and amniotic fluidderived stem cells [13]. The present study used skeletal muscle-derived precursor cells (skMPCs), shown in rodents, dogs, and nonhuman primates to directly integrate into the sphincter musculature and restore its volume and function, restoring somatic and adrenergic innervation and vasculature [14][15][16][17][18].…”

Sulforaphane Treatment of Stress Urinary Incontinence Via the Nrf2-ARE Pathway in a Rat Model

“…Various sling surgeries are more efficacious and prevalent but are associated with larvaceous complications, such as urinary tract injury and infection [8]. The exact regeneration mechanism of stem cells injection therapy is unknown so safety may be a problem, which is the limitation of stem cell therapy for SUI [9]. …”