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BACKGROUND: Clinical trials have provided evidence that transplants of dopaminergic precursors, which may be replaced by new in vitro stem cell sources, can integrate into the host tissue, and alleviate motor symptoms in Parkinson´s disease (PD). In some patients, deterioration of graft function occurred several months after observing a graft-derived functional improvement. Rejection of peripheral organs was initially related to HLA-specific antibodies. However, the role of non-HLA antibodies is now considered also relevant for rejection. Angiotensin-II type-1 receptor autoantibodies (AT1-AA) act as agonists of the AT1 receptors. AT1-AA are the non-HLA antibodies most widely associated with graft dysfunction or rejection after transplantation of different solid organs and hematopoietic stem cells. However, it is not known about the presence and possible functional effects of AT1-AA in dopaminergic grafts, and the effects of treatment with AT1 receptor blockers (ARBs) such as candesartan on graft survival. METHODS: In a 6-hydroxydopamine PD rat model, we studied the short-term (10 days)- and long-term (3 months) effects of chronic treatment with the ARB candesartan on survival of grafted dopaminergic neurons and microglial graft infiltration, as well as the effects of dopaminergic denervation and grafting on serum and CSF AT1-AA levels. The expression of AT1 receptors in grafted neurons was determined by laser capture microdissection. RESULTS: At the early period post-grafting, the number of grafted dopaminergic neurons that survived was not significantly different between treated and untreated hosts (i.e., control rats and rats treated with candesartan), probably because, just after grafting, other deleterious factors are predominant for dopaminergic cell death, such as mechanical trauma, lack of growth factors/nutrients and ischemia. However, several months post-grafting, we observed a significantly higher number of surviving dopaminergic neurons and a higher density of striatal dopaminergic terminals in the candesartan-treated group. For several months, grafted rats showed blood and cerebrospinal fluid levels of AT1-AA higher than normal controls, and also higher AT1-AA levels than non-grafted parkinsonian rats. CONCLUSIONS: The results suggest the use of ARBs such as candesartan in PD patients, particularly before and after dopaminergic grafts, and the need to monitor AT1-AA levels in PD patients, particularly in those candidates for dopaminergic grafting.
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Autoanticuerpos , Neuronas Dopaminérgicas , Enfermedad de Parkinson , Receptor de Angiotensina Tipo 1 , Animales , Ratas , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Autoanticuerpos/inmunología , Bencimidazoles/farmacología , Bencimidazoles/uso terapéutico , Compuestos de Bifenilo/farmacología , Compuestos de Bifenilo/uso terapéutico , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/metabolismo , Oxidopamina/farmacología , Enfermedad de Parkinson/terapia , Enfermedad de Parkinson/patología , Ratas Sprague-Dawley , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 1/inmunología , Tetrazoles/farmacología , Tetrazoles/uso terapéuticoRESUMEN
This study compared the efficacy of graft-versus-host disease (GVHD) prophylaxis with post-transplantation cyclophosphamide (PTCy) and tacrolimus (Tac) versus other regimens in 272 adults undergoing peripheral blood (PB) allogeneic hematopoietic cell transplantation (allo-HCT) from HLA-matched donors. Of these 272 patients, 95 (34.9%) received PTCy/Tac. The times to neutrophil and platelet engraftment were longer in the PTCy/Tac group (20 days versus 16 days for neutrophils and 19 days versus 12 days for platelets). The day +30 cumulative incidence (CuI) of bacterial bloodstream infection was higher in the PTCy/Tac group (43.2% versus 13.0%; P < .001). The CuIs of grade II-IV and grade III-IV acute GVHD (aGVHD) at day +180 were 14.7% and 4.2%, and the CuI of moderate/severe cGVHD at 2 years was 2.4% in the PTCy/Tac group and 41.8% (hazard ratio [HR], .29; P < .001), 15.8%, (HR, .24; P = .007), and 47.0% (HR, .05; P < .001), respectively, in the no-PTCy group. The duration of immunosuppression was shorter in patients receiving PTCy/Tac (6.2 months versus 9.0 months; P < .001). PTCy/Tac patients had higher OS (2 years: 74.3% versus 60.9%; HR, .54; P = .012), lower NRM (2 years: 8.6% versus 15.8%; HR, .54; P = .11), comparable CuI of relapse (2 years: 26.0% versus 24.4%; HR, 1.03; P = .89), and higher GRFS (2 years: 59.1% versus 16.7%; HR, .32; P < .001). Using PTCy/Tac in HLA-matched PB allo-HCT improved transplantation outcomes at out institution compared with previous prophylactic regimens, including a higher probability of survival despite more delayed engraftment and a higher rate of bacterial infection.
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Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Adulto , Humanos , Tacrolimus/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Ciclofosfamida/uso terapéutico , Enfermedad Injerto contra Huésped/prevención & control , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Donantes de TejidosRESUMEN
Tumor grafts grown on the chorioallantoic membrane (CAM) of chicken embryos represent a transition between cell culture and mammalian in vivo models. Magnetic resonance imaging (MRI) started to harness this potential. Functional gas challenge is feasible on the CAM. Using quantitative T1 and T2* mapping, we characterized the response of MC-38 colon, A549, and H460 adeno-carcinoma cell grafts to hypercapnic (HC) and hypercapnic-hyperoxic (HCHO) gas challenges, pertaining to the grafts' vascular and oxygenation phenotypes. MR imaging revealed that larger T1 and T2* were located in the center of H460 and MC-38 tumors. Quantitative analysis showed a significant reduction in T1 and a significant increase in T2* in response to HCHO for A549 grafts, while H460 and MC-38 tumors did not respond to either gas challenge. Different tumor grafts respond differentially to HC and HCHO conditions. A549 tumor grafts, with higher vessel density and smaller tumor diameter compared with H460 and MC-38 grafts, had a significant response in T1 for HCHO and T2* increased slightly during HC and significantly under HCHO, consistent with a normoxic phenotype and functional vasoreactivity. Therefore, gas challenges enable differential characterization of tumor grafts with respect to their vascular and oxygenation status.
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High-dose chemotherapy with autologous stem cell support (ASCT) is the standard of care for eligible newly diagnosed Multiple Myeloma (MM) patients. Stem cell graft contamination by aberrant plasma cells (APCs) has been considered a possible predictive marker of subsequent clinical outcome, but the limited reports to date present unclear conclusions. We prospectively estimated the frequency of graft contamination using highly sensitive next-generation flow cytometry and evaluated its clinical impact in 199 myeloma patients who underwent an ASCT. Contamination (con+) was detected in 79/199 patients at a median level 2 × 10-5. Its presence and levels were correlated with response to induction treatment, with 94%, 71% and 43% achieving CR, VGPR and PR, respectively. Importantly, con+ grafts conferred 2-fold and 2.8-fold higher patient-risk of not achieving or delaying reaching CR (4 vs. 11 months) and MRD negativity (5 vs. 18 months) post ASCT, respectively. Our data also provide evidence of a potentially skewed bone marrow (BM) reconstitution due to unpurged grafts, since con+ derived BM had significantly higher prevalence of memory B cells. These data, together with the absence of significant associations with baseline clinical features, highlight graft contamination as a potential biomarker with independent prognostic value for deeper responses, including MRD negativity. Longer follow-up will reveal if this corresponds to PFS or OS advantage.
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Allogeneic hematopoietic stem cell transplantation (HSCT) is a potential cure for patients with hematological malignancies but substantial risks of recurrence of the malignant disease remain. TCR γδ and NK cells are perceived as potent innate effector cells in HSCT and have been associated with post-transplant protection from relapse in clinical studies. Immunocompetent cells from the donor are crucial for patient outcomes and peripheral blood stem cells (PBSC) are being increasingly applied as graft source. G-CSF is the preferential mobilizing agent in healthy donors for PBSC grafts, yet effects of G-CSF on TCR γδ and NK cells are scarcely uncovered and could influence the graft composition and potency of these cells. Therefore, we analyzed T and NK cell subsets and activation markers in peripheral blood samples of 49 donors before and after G-CSF mobilization and-for a subset of donors-also in the corresponding graft samples using multicolor flowcytometry with staining for CD3, CD4, CD8, TCRαß, TCRγδ, Vδ1, Vδ2, HLA-DR, CD45RA, CD197, CD45RO, HLA-DR, CD16, CD56, and CD314. We found that TCR γδ cells were mobilized and harvested with an efficiency corresponding that of TCR αß cells. For TCR γδ as well as for TCR αß cells, G-CSF preferentially mobilized naïve and terminally differentiated effector (TEMRA) cells over memory cells. In the TCR γδ cell compartment, G-CSF preferentially mobilized cells of the nonVδ2 types and increased the fraction of HLA-DR positive TCR γδ cells. For NK cells, mobilization by G-CSF was increased compared to that of T cells, yet NK cells appeared to be less efficiently harvested than T cells. In the NK cell compartment, G-CSF-stimulation preserved the proportion of CD56dim NK effector cells which have been associated with relapse protection. The expression of the activating receptor NKG2D implied in anti-leukemic responses, was significantly increased in both CD56dim and CD56bright NK cells after G-CSF stimulation. These results indicate differentiated mobilization and altering properties of G-CSF which could improve the effects of donor TCR γδ and NK cells in the processes of graft-versus-leukemia for relapse prevention after HSCT.
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Filgrastim/uso terapéutico , Efecto Injerto vs Leucemia , Movilización de Célula Madre Hematopoyética , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/trasplante , Trasplante de Células Madre de Sangre Periférica , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Linfocitos T/efectos de los fármacos , Linfocitos T/trasplante , Antígeno CD56/metabolismo , Diferenciación Celular/efectos de los fármacos , Filgrastim/efectos adversos , Citometría de Flujo , Movilización de Célula Madre Hematopoyética/efectos adversos , Humanos , Inmunofenotipificación , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Activación de Linfocitos/efectos de los fármacos , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Trasplante de Células Madre de Sangre Periférica/efectos adversos , Fenotipo , Receptores de Antígenos de Linfocitos T gamma-delta/metabolismo , Linfocitos T/inmunología , Linfocitos T/metabolismo , Donantes de Tejidos , Trasplante Homólogo , Resultado del TratamientoRESUMEN
Hippocampal damage after status epilepticus (SE) leads to multiple epileptogenic changes, which lead to chronic temporal lobe epilepsy (TLE). Morbidities such as spontaneous recurrent seizures (SRS) and memory and mood impairments are seen in a significant fraction of SE survivors despite the administration of antiepileptic drugs after SE. We examined the efficacy of bilateral intra-hippocampal grafting of neural stem/progenitor cells (NSCs) derived from the embryonic day 19 rat hippocampi, six days after SE for restraining SE-induced SRS, memory, and mood impairments in the chronic phase. Grafting of NSCs curtailed the progression of SRS at 3-5 months post-SE and reduced the frequency and severity of SRS activity when examined at eight months post-SE. Reduced SRS activity was also associated with improved memory function. Graft-derived cells migrated into different hippocampal cell layers, differentiated into GABA-ergic interneurons, astrocytes, and oligodendrocytes. Significant percentages of graft-derived cells also expressed beneficial neurotrophic factors such as the fibroblast growth factor-2, brain-derived neurotrophic factor, insulin-like growth factor-1 and glial cell line-derived neurotrophic factor. NSC grafting protected neuropeptide Y- and parvalbumin-positive host interneurons, diminished the abnormal migration of newly born neurons, and rescued the reelin+ interneurons in the dentate gyrus. Besides, grafting led to the maintenance of a higher level of normal neurogenesis in the chronic phase after SE and diminished aberrant mossy fiber sprouting in the dentate gyrus. Thus, intrahippocampal grafting of hippocampal NSCs shortly after SE considerably curbed the progression of epileptogenic processes and SRS, which eventually resulted in less severe chronic epilepsy devoid of significant cognitive and mood impairments.
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Spinal cord injury (SCI) has been associated with a dismal prognosis-recovery is not expected, and the most standard interventions have been temporizing measures that do little to mitigate the extent of damage. While advances in surgical and medical techniques have certainly improved this outlook, limitations in functional recovery continue to impede clinically significant improvements. These limitations are dependent on evolving immunological mechanisms that shape the cellular environment at the site of SCI. In this review, we examine these mechanisms, identify relevant cellular components, and discuss emerging treatments in stem cell grafts and adjuvant immunosuppressants that target these pathways. As the field advances, we expect that stem cell grafts and these adjuvant treatments will significantly shift therapeutic approaches to acute SCI with the potential for more promising outcomes.
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Rechazo de Injerto/prevención & control , Enfermedad Injerto contra Huésped/prevención & control , Inmunosupresores/uso terapéutico , Células Madre Pluripotentes Inducidas/trasplante , Células Precursoras de Oligodendrocitos/trasplante , Traumatismos de la Médula Espinal/terapia , Adyuvantes Inmunológicos , Aloinjertos , Animales , Basiliximab/uso terapéutico , Células Cultivadas , Ensayos Clínicos como Asunto , Ciclosporina/uso terapéutico , Femenino , Supervivencia de Injerto/inmunología , Células Madre Embrionarias Humanas/citología , Células Madre Embrionarias Humanas/inmunología , Humanos , Células Madre Pluripotentes Inducidas/inmunología , Masculino , Ratones , Ácido Micofenólico/uso terapéutico , Células Precursoras de Oligodendrocitos/inmunología , Ratas , Tacrolimus/uso terapéutico , Trasplante AutólogoRESUMEN
To date, different methods of isolation of amniotic stem cells have been developed. Our previous studies have demonstrated that there are significant differences in viability and efficiency of the isolation and culture process depending on the enzyme and medium used. The aim of this study was to present efficient protocol, which can be used within good manufacturing practise conditions. Amniotic membranes were obtained from ten woman 31-39 years old who signed informed constent. GMP regulations are applicable. The described protocol aims to obtain a clinically significant cell yield (>1*108). The cells may be maintained in the growth phase even for 2 months. The mesenchymal cells constitute about 75-95% of the cells in primary culture. Supervisory authorities require repetitive and reproducible laboratory protocol for stem cells culture. Presented protocol allow achieving clinically significant cell yield (>1*108) in 4-5 weeks. Cells can be transplanted as suspension or cell sheet.
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Amnios/citología , Separación Celular/métodos , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Cultivo Primario de Células/métodos , Adulto , Separación Celular/normas , Células Cultivadas , Técnicas de Laboratorio Clínico/métodos , Femenino , Humanos , Trasplante de Células Madre Mesenquimatosas/métodos , Trasplante de Células Madre Mesenquimatosas/normas , Embarazo , Cultivo Primario de Células/normas , Reproducibilidad de los Resultados , Recolección de Tejidos y Órganos/métodos , Recolección de Tejidos y Órganos/normasRESUMEN
BACKGROUND: Peripheral blood stem cells from healthy donors mobilized by granulocyte colony-stimulating factor (G-CSF) and thereafter harvested by leukapheresis are commonly used for allogeneic stem cell transplantation. METHODS: Plasma levels of 38 soluble mediators (cytokines, soluble adhesion molecules, proteases, protease inhibitors) were analyzed in samples derived from healthy stem cell donors before G-CSF treatment and after 4 days, both immediately before and after leukapheresis. RESULTS: Donors could be classified into two main subsets based on their plasma mediator profile before G-CSF treatment. Seventeen of 36 detectable mediators were significantly altered by G-CSF; generally an increase in mediator levels was seen, including pro-inflammatory cytokines, soluble adhesion molecules and proteases. Several leukocyte- and platelet-released mediators were increased during apheresis. Both plasma and graft mediator profiles were thus altered and showed correlations to graft concentrations of leukocytes and platelets; these concentrations were influenced by the apheresis device used. Finally, the mediator profile of the allotransplant recipients was altered by graft infusion, and based on their day +1 post-transplantation plasma profile our recipients could be divided into two major subsets that differed in overall survival. DISCUSSION: G-CSF alters the short-term plasma mediator profile of healthy stem cell donors. These effects together with the leukocyte and platelet levels in the graft determine the mediator profile of the stem cell grafts. Graft infusion also alters the systemic mediator profile of the recipients, but further studies are required to clarify whether such graft-induced alterations have a prognostic impact.
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Eliminación de Componentes Sanguíneos , Movilización de Célula Madre Hematopoyética , Factores Inmunológicos/metabolismo , Donantes de Tejidos , Adulto , Anciano , Aloinjertos/efectos de los fármacos , Plaquetas/citología , Citocinas/sangre , Supervivencia sin Enfermedad , Femenino , Factor Estimulante de Colonias de Granulocitos/farmacología , Trasplante de Células Madre Hematopoyéticas , Humanos , Leucocitos/citología , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , SolubilidadRESUMEN
Although there have been many pharmacological agents considered to be neuroprotective therapy in Parkinson's disease (PD) patients, neurosurgical approaches aimed to neuroprotect or restore the degenerative nigrostriatal system have rarely been the focus of in depth reviews. Here, we explore the neuroprotective strategies involving invasive surgical approaches (NSI) using neurotoxic models 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 6-hydroxydopamine (6-OHDA), which have led to clinical trials. We focus on several NSI approaches, namely deep brain stimulation of the subthalamic nucleus, glial neurotrophic derived factor (GDNF) administration and cell grafting methods. Although most of these interventions have produced positive results in preclinical animal models, either from behavioral or histological studies, they have generally failed to pass randomized clinical trials to validate each approach. We argue that NSI are promising approaches for neurorestoration in PD, but preclinical studies should be planned carefully in order not only to detect benefits but also to detect potential adverse effects. Further, clinical trials should be designed to be able to detect and disentangle neuroprotection from symptomatic effects. In summary, our review study evaluates the pertinence of preclinical models to study NSI for PD and how this affects their efficacy when translated into clinical trials.
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Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Estimulación Encefálica Profunda/métodos , Factor Neurotrófico Derivado de la Línea Celular Glial/administración & dosificación , Enfermedad de Parkinson/prevención & control , Animales , Ensayos Clínicos como Asunto , Modelos Animales de Enfermedad , Factor Neurotrófico Derivado de la Línea Celular Glial/farmacología , Humanos , Neuroprotección , Enfermedad de Parkinson/etiología , Enfermedad de Parkinson/terapia , Resultado del TratamientoRESUMEN
UNLABELLED: : As clinical application of neural stem cell (NSC) grafting into the brain would also encompass aged people, critical evaluation of engraftment of NSC graft-derived cells in the aged hippocampus has significance. We examined the engraftment and differentiation of alkaline phosphatase-positive NSCs expanded from the postnatal subventricular zone (SVZ), 3 months after grafting into the intact young or aged rat hippocampus. Graft-derived cells engrafted robustly into both young and aged hippocampi. Although most graft-derived cells pervasively migrated into different hippocampal layers, the graft cores endured and contained graft-derived neurons expressing neuron-specific nuclear antigen (NeuN) and γ-amino butyric acid in both groups. A fraction of migrated graft-derived cells in the neurogenic subgranular zone-granule cell layer also expressed NeuN. Neuronal differentiation was, however, occasionally seen amid graft-derived cells that had migrated into non-neurogenic regions, where substantial fractions differentiated into S-100ß+ astrocytes, NG2+ oligodendrocyte progenitors, or Olig2+ putative oligodendrocytes. In both age groups, graft cores located in non-neurogenic regions displayed many doublecortin-positive (DCX+) immature neurons at 3 months after grafting. Analyses of cells within graft cores using birth dating and putative NSC markers revealed that DCX+ neurons were newly born neurons derived from engrafted cells and that putative NSCs persisted within the graft cores. Thus, both young and aged hippocampi support robust engraftment and similar differentiation of SVZ-NSC graft-derived cells. Furthermore, some grafted NSCs retain the "stemness" feature and produce new neurons even at 3 months after grafting, implying that grafting of SVZ-NSCs into the young or aged hippocampus leads to establishment of new neurogenic niches in non-neurogenic regions. SIGNIFICANCE: The results demonstrate that advanced age of the host at the time of grafting has no major adverse effects on engraftment, migration, and differentiation of grafted subventricular zone-neural stem cells (SVZ-NSCs) in the intact hippocampus, as both young and aged hippocampi promoted excellent engraftment, migration, and differentiation of SVZ-NSC graft-derived cells in the present study. Furthermore, SVZ-NSC grafts showed ability for establishing neurogenic niches in non-neurogenic regions, generating new neurons for extended periods after grafting. This phenomenon will be beneficial if these niches can continuously generate new neurons and glia in the grafted hippocampus, as newly generated neurons and glia are expected to improve, not only the microenvironment, but also the plasticity and function of the aged hippocampus. Overall, these results have significance because the potential application of NSC grafting for treatment of neurodegenerative disorders at early stages of disease progression and age-related impairments would mostly involve aged persons as recipients.
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Envejecimiento , Hipocampo/citología , Ventrículos Laterales/citología , Células-Madre Neurales/citología , Células-Madre Neurales/trasplante , Animales , Diferenciación Celular , Proteína Doblecortina , Técnica del Anticuerpo Fluorescente , Ratas , Ratas Endogámicas F344 , Nicho de Células Madre , Trasplante de Células Madre/métodosRESUMEN
Diminution in the number of gamma-amino butyric acid positive (GABA-ergic) interneurons and their axon terminals, and/or alterations in functional inhibition are conspicuous brain alterations believed to contribute to the persistence of seizures in acquired epilepsies such as temporal lobe epilepsy. This has steered a perception that replacement of lost GABA-ergic interneurons would improve inhibitory synaptic neurotransmission in the epileptic brain region and thereby reduce the occurrence of seizures. Indeed, studies using animal prototypes have reported that grafting of GABA-ergic progenitors derived from multiple sources into epileptic regions can reduce seizures. This review deliberates recent advances, limitations and challenges concerning the development of GABA-ergic cell therapy for epilepsy. The efficacy and limitations of grafts of primary GABA-ergic progenitors from the embryonic lateral ganglionic eminence and medial ganglionic eminence (MGE), neural stem/progenitor cells expanded from MGE, and MGE-like progenitors generated from human pluripotent stem cells for alleviating seizures and co-morbidities of epilepsy are conferred. Additional studies required for possible clinical application of GABA-ergic cell therapy for epilepsy are also summarized.
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Diferenciación Celular/fisiología , Epilepsia del Lóbulo Temporal/terapia , Epilepsia/terapia , Neuronas GABAérgicas/citología , Células-Madre Neurales/citología , Animales , Epilepsia/fisiopatología , Hipocampo/citología , HumanosRESUMEN
Several neurological and psychiatric disorders present hyperexcitability of neurons in specific regions of the brain or spinal cord, partly because of some loss and/or dysfunction of gamma-amino butyric acid positive (GABA-ergic) inhibitory interneurons. Strategies that enhance inhibitory neurotransmission in the affected brain regions may therefore ease several or most deficits linked to these disorders. This perception has incited a huge interest in testing the efficacy of GABA-ergic interneuron cell grafting into regions of the brain or spinal cord exhibiting hyperexcitability, dearth of GABA-ergic interneurons or impaired inhibitory neurotransmission, using preclinical models of neurological and psychiatric disorders. Interneuron progenitors from the embryonic ventral telencephalon capable of differentiating into diverse subclasses of interneurons have particularly received much consideration because of their ability for dispersion, migration and integration with the host neural circuitry after grafting. The goal of this review is to discuss the premise, scope and advancement of GABA-ergic cell therapy for easing neurological deficits in preclinical models of schizophrenia, chronic neuropathic pain, Alzheimer's disease and Parkinson's disease. As grafting studies in these prototypes have so far utilized either primary cells from the embryonic medial and lateral ganglionic eminences or neural progenitor cells expanded from these eminences as donor material, the proficiency of these cell types is highlighted. Moreover, future studies that are essential prior to considering the possible clinical application of these cells for the above neurological conditions are proposed. Particularly, the need for grafting studies utilizing medial ganglionic eminence-like progenitors generated from human pluripotent stem cells via directed differentiation approaches or somatic cells through direct reprogramming methods are emphasized. This article is part of a Special Issue entitled SI: PSC and the brain.
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Enfermedad de Alzheimer/terapia , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Neuronas GABAérgicas/trasplante , Enfermedad de Parkinson/terapia , Esquizofrenia/terapia , Diferenciación Celular/fisiología , Humanos , Interneuronas/citología , Células-Madre Neurales/citología , Neuralgia/terapia , Células Madre Pluripotentes/citologíaRESUMEN
Huntington's disease (HD) is an autosomal dominant inherited disorder leading to the loss inter alia of DARPP-32 positive medium spiny projection neurons ("MSNs") in the striatum. There is no known cure for HD but the relative specificity of cell loss early in the disease has made cell replacement by neural transplantation an attractive therapeutic possibility. Transplantation of human fetal striatal precursor cells has shown "proof-of-principle" in clinical trials; however, the practical and ethical difficulties associated with sourcing fetal tissues have stimulated the need to identify alternative source(s) of donor cells that are more readily available and more suitable for standardization. We now have available the first generation of protocols to generate DARPP-32 positive MSN-like neurons from pluripotent stem cells and these have been successfully grafted into animal models of HD. However, whether these grafts can provide stable functional recovery to the level that can regularly be achieved with primary fetal striatal grafts remains to be demonstrated. Of particular concern, primary fetal striatal grafts are not homogenous; they contain not only the MSN subpopulation of striatal projection neurons but also include all the different cell types that make up the mature striatum, such as the multiple populations of striatal interneurons and striatal glia, and which certainly contribute to normal striatal function. By contrast, present protocols for pluripotent stem cell differentiation are almost entirely targeted at specifying just neurons of an MSN lineage. So far, evidence for the functionality and integration of stem-cell derived grafts is correspondingly limited. Indeed, consideration of the features of full striatal reconstruction that is achieved with primary fetal striatal grafts suggests that optimal success of the next generations of stem cell-derived replacement therapy in HD will require that graft protocols be developed to allow inclusion of multiple striatal cell types, such as interneurons and/or glia. Almost certainly, therefore, more sophisticated differentiation protocols will be necessary, over and above replacement of a specific population of MSNs. A rational solution to this technical challenge requires that we re-address the underlying question-what constitutes a functional striatal graft?
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Objective To explore the difference of immunological characteristics between recombination human granulocyte colony-stimulating factor(rhG-CSF)mobilized peripheral blood grafts(G-PB)and steady-state bone marrow grafts(SS-BM).Methods From April to October 2003,G-PB and SS-BM of 15 related donors were collected.T cell subgroups,dendritic cells(DC),monocytes and the expression of CD28 costimulatory molecules on T cells were determined by multicolor flow cytometry.The lymphocyte proliferation ability and the quantities of interleukin-4(IL-4)and interferon-?(IFN-?)secreted by T cells were determined using MTT assays and sandwich ELISA.Results The absolute numbers of monocytes,CD3+,CD4+ and CD8+ T cells,and the ratios of CD4/CD8 in G-PB were significantly higher than those in SS-BM,respectively(P0.05).The quantities of IFN-? and IL-4 secreted by T cells per micromilter in G-PB was significantly higher than those in SS-BM(P0.05).The absolute numbers of DC1 and DC2 in G-PB were significantly higher than those in SS-BM(P0.05).Conclusion It is concluded that the difference of immunological characteristics between G-PB and SS-BM may explain the lower incidence of GVHD and lower relapse rate after SS-BM and G-PB transplantation.