60 research outputs found
Autocrine Production of IGFâI Increases Stem CellâMediated Neuroprotection
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder resulting in motor neuron (MN) loss. There are currently no effective therapies; however, cellular therapies using neural progenitor cells protect MNs and attenuate disease progression in G93AâSOD1 ALS rats. Recently, we completed a phase I clinical trial examining intraspinal human spinal stem cell (HSSC) transplantation in ALS patients which demonstrated our approach was safe and feasible, supporting the phase II trial currently in progress. In parallel, efforts focused on understanding the mechanisms underlying the preclinical benefit of HSSCs in vitro and in animal models of ALS led us to investigate how insulinâlike growth factorâI (IGFâI) production contributes to cellular therapy neuroprotection. IGFâI is a potent growth factor with proven efficacy in preclinical ALS studies, and we contend that autocrine IGFâI production may enhance the salutary effects of HSSCs. By comparing the biological properties of HSSCs to HSSCs expressing sixfold higher levels of IGFâI, we demonstrate that IGFâI production augments the production of glialâderived neurotrophic factor and accelerates neurite outgrowth without adversely affecting HSSC proliferation or terminal differentiation. Furthermore, we demonstrate that increased IGFâI induces more potent MN protection from excitotoxicity via both indirect and direct mechanisms, as demonstrated using hanging inserts with primary MNs or by culturing with organotypic spinal cord slices, respectively. These findings support our theory that combining autocrine growth factor production with HSSC transplantation may offer a novel means to achieve additive neuroprotection in ALS. Stem Cells 2015;33:1480â1489Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111155/1/stem1933.pd
Intraspinal neural stem cell transplantation in amyotrophic lateral sclerosis: Phase 1 trial outcomes
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106747/1/ana24113.pd
Human neural stem cell transplantation into the corpus callosum of Alzheimerâs mice
The hippocampus has been the target of stem cell transplantations in preclinical studies focused on Alzheimerâs disease, with results showing improvements in histological and behavioral outcomes. The corpus callosum is another structure that is affected early in Alzheimerâs disease. Therefore, we hypothesize that this structure is a novel target for human neural stem cell transplantation in transgenic Alzheimerâs disease mouse models. This study demonstrates the feasibility of targeting the corpus callosum and identifies an effective immunosuppression regimen for transplanted neural stem cell survival. These results support further preclinical development of the corpus callosum as a therapeutic target in Alzheimerâs disease.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138852/1/acn3443_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138852/2/acn3443.pd
Human Cortical Neural Stem Cells Expressing InsulinâLike Growth FactorâI: A Novel Cellular Therapy for Alzheimerâs Disease
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135291/1/sct3201653379.pd
Analysis of graft survival in a trial of stem cell transplant in ALS
Objective The first US Food and Drug Administrationâapproved clinical trial to treat amyotrophic lateral sclerosis ( ALS ) with neural stem cellâbased therapy is in progress. The goal of the current study was to identify and assess the survival of human spinal cordâderived neural stem cells ( HSSC s) transplanted into the spinal cord in patients with ALS . Methods Spinal cords transplanted with HSSCs were examined from six autopsy cases. Homogenized tissues were interrogated for the presence of donor versus recipient DNA using realâtime PCR methods ( qPCR ). Fluorescence in situ hybridization (FISH) was performed using DNA probes for XY chromosomes to identify male donor HSSCs in one female case, and immunohistochemistry (IHC) was used to characterize the identified donor cells. Results Genomic DNA from donor HSSC s was identified in all cases, comprising 0.67â5.4% of total tissue DNA in patients surviving 196 to 921Â days after transplantation. In the one female patient a ânestâ of cells identified on H&E staining were XY âpositive by FISH , confirming donor origin. A subset of XY âpositive cells labeled for the neuronal marker NeuN and stem cell marker SOX 2. Interpretation This is the first study to identify human neural stem cells transplanted into a human spinal cord. Transplanted HSSC s survived up to 2.5Â years posttransplant. Some cells differentiated into neurons, while others maintained their stem cell phenotype. This work is a proof of concept of the survival and differentiation of human stems cell transplanted into the spinal cord of ALS patients.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109593/1/acn3134.pd
Extensive Neuronal Differentiation of Human Neural Stem Cell Grafts in Adult Rat Spinal Cord
BACKGROUND: Effective treatments for degenerative and traumatic diseases of the nervous system are not currently available. The support or replacement of injured neurons with neural grafts, already an established approach in experimental therapeutics, has been recently invigorated with the addition of neural and embryonic stem-derived precursors as inexhaustible, self-propagating alternatives to fetal tissues. The adult spinal cord, i.e., the site of common devastating injuries and motor neuron disease, has been an especially challenging target for stem cell therapies. In most cases, neural stem cell (NSC) transplants have shown either poor differentiation or a preferential choice of glial lineages. METHODS AND FINDINGS: In the present investigation, we grafted NSCs from human fetal spinal cord grown in monolayer into the lumbar cord of normal or injured adult nude rats and observed large-scale differentiation of these cells into neurons that formed axons and synapses and established extensive contacts with host motor neurons. Spinal cord microenvironment appeared to influence fate choice, with centrally located cells taking on a predominant neuronal path, and cells located under the pia membrane persisting as NSCs or presenting with astrocytic phenotypes. Slightly fewer than one-tenth of grafted neurons differentiated into oligodendrocytes. The presence of lesions increased the frequency of astrocytic phenotypes in the white matter. CONCLUSIONS: NSC grafts can show substantial neuronal differentiation in the normal and injured adult spinal cord with good potential of integration into host neural circuits. In view of recent similar findings from other laboratories, the extent of neuronal differentiation observed here disputes the notion of a spinal cord that is constitutively unfavorable to neuronal repair. Restoration of spinal cord circuitry in traumatic and degenerative diseases may be more realistic than previously thought, although major challenges remain, especially with respect to the establishment of neuromuscular connections
Longâterm Phase 1/2 intraspinal stem cell transplantation outcomes in ALS
ObjectiveIntraspinal human spinal cordâderived neural stem cell (HSSC) transplantation is a potential therapy for amyotrophic lateral sclerosis (ALS); however, previous trials lack controls. This post hoc analysis compared ambulatory limbâonset ALS participants in Phase 1 and 2 (Ph1/2) openâlabel intraspinal HSSC transplantation studies up to 3 years after transplant to matched participants in Pooled Resource OpenâAccess ALS Clinical Trials (PROâACT) and ceftriaxone datasets to provide required analyses to inform future clinical trial designs.MethodsSurvival, ALSFRSâR, and a composite statistic (ALS/SURV) combining survival and ALS Functional Rating Scale revised (ALSFRSâR) functional status were assessed for matched participant subsets: PROâACT n = 1108, Ph1/2 n = 21 and ceftriaxone n = 177, Ph1/2 n = 20.ResultsSurvival did not differ significantly between cohorts: Ph1/2 median survival 4.7 years, 95% CI (1.2, â) versus PROâACT 2.3 years (1.9, 2.5), P = 1.0; Ph1/2 3.0 years (1.2, 5.6) versus ceftriaxone 2.3 years (1.8, 2.8), P = 0.88. Mean ALSFRSâR at 24 months significantly differed between Ph1/2 and both comparison cohorts (Ph1/2 30.1 ± 8.6 vs. PROâACT 24.0 ± 10.2, P = 0.048; Ph1/2 30.7 ± 8.8 vs. ceftriaxone 19.2 ± 9.5, P = 0.0023). Using ALS/SURV, median PROâACT and ceftriaxone participants died by 24 months, whereas median Ph1/2 participant ALSFRSâRs were 23 (P = 0.0038) and 19 (P = 0.14) in PROâACT and ceftriaxone comparisons at 24 months, respectively, supporting improved functional outcomes in the Ph1/2 study.InterpretationComparison of Ph1/2 studies to historical datasets revealed significantly improved survival and function using ALS/SURV versus PROâACT controls. While results are encouraging, comparison against historical populations demonstrate limitations in noncontrolled studies. These findings support continued evaluation of HSSC transplantation in ALS, support the benefit of control populations, and enable necessary power calculations to design a randomized, sham surgeryâcontrolled efficacy study.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/144287/1/acn3567_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/144287/2/acn3567.pd
Feasibility of Human Neural Stem Cell Transplantation for the Treatment of Acute Subdural Hematoma in a Rat Model: A Pilot Study
Human neural stem cells (hNSCs) transplantation in several brain injury models has established their therapeutic potential. However, the feasibility of hNSCs transplantation is still not clear for acute subdural hematoma (ASDH) brain injury that needs external decompression. Thus, the aim of this pilot study was to test feasibility using a rat ASDH decompression model with two clinically relevant transplantation methods. Two different methods, in situ stereotactic injection and hNSC-embedded matrix seating on the brain surface, were attempted. Athymic rats were randomized to uninjured or ASDH groups (F344/NJcl-rnu/rnu, n = 7â10/group). Animals in injury group were subjected to ASDH, and received decompressive craniectomy and 1-week after decompression surgery were transplanted with green fluorescent protein (GFP)-transduced hNSCs using one of two approaches. Histopathological examinations at 4 and 8 weeks showed that the GFP-positive hNSCs survived in injured brain tissue, extended neurite-like projections resembling neural dendrites. The in situ transplantation group had greater engraftment of hNSCs than matrix embedding approach. Immunohistochemistry with doublecortin, NeuN, and GFAP at 8 weeks after transplantation showed that transplanted hNSCs remained as immature neurons and did not differentiate toward to glial cell lines. Motor function was assessed with rotarod, compared to control group (n = 10). The latency to fall from the rotarod in hNSC in situ transplanted rats was significantly higher than in control rats (median, 113 s in hNSC vs. 69 s in control, P = 0.02). This study first demonstrates the robust engraftment of in situ transplanted hNSCs in a clinically-relevant ASDH decompression rat model. Further preclinical studies with longer study duration are warranted to verify the effectiveness of hNSC transplantation in amelioration of TBI induced deficits
Characterization Of A Human Fetal Spinal Cord Stem Cell Line, Nsi-566Rsc, And Its Induction To Functional Motoneurons
Specific neuronal subtypes, especially motoneurons (MNs), derived from human stem cells provide a significant therapeutic potential for spinal cord diseases, such as amyotrophic lateral sclerosis (ALS) and spinal cord injury. So far, in vitro, MNs have only been successfully induced from embryonic stem cells (hESC) and human fetal cortical progenitors. Although neural progenitors from spinal cord would be a likely source for generating MNs, there has been no study reporting successful in vitro differentiation of MNs from spinal cord progenitors. This study first characterized a polyclonal spinal cord stem cell line isolated from an 8 week-old fetus. Then a paradigm was introduced to successfully induce MNs from this cell line, which was demonstrated by immunostaining using the MN markers HB9, Islet1 and choline acetyl transferase (ChAT). The combination of HB9 and ChAT immunostainings indicated that âŒ20% of the cells were MNs after this induction protocol. The presence of other cell types in the differentiated culture was also analysed. Finally, the electrophysiological properties of these differentiated MNs were characterized to confirm their functional integrity. The majority of these MNs fired repetitive action potentials (APs), which is an indicator of functional maturation. The recordings of spontaneous excitatory postsynaptic currents (EPSCs) confirmed the formation of synapses onto these MNs. This study reports the first successful differentiation of MNs from human spinal cord stem cells in vitro, providing a novel approach for obtaining functional MNs when designing the therapeutic strategy for spinal cord diseases or injuries. Copyright © 2009 John Wiley & Sons, Ltd
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