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1.
Transfusion ; 63(4): 782-790, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36924403

RESUMO

BACKGROUND: The success of allogeneic hematopoietic stem cell transplantation is dependent on a world-wide network of collection centers providing donations that predominantly have been infused as fresh cells. The logistics chain that supports the just-in-time delivery model for stem cell and immunotherapy products was severely stressed by the COVID pandemic, and in early 2020 a number of national and international bodies recommended that cells should be cryopreserved at the collection or transplant center to avoid interruptions in their acquisition or delivery to patients who had started conditioning. STUDY DESIGN: To assess the potential consequences of such pandemic-related deviations to normal practice, we surveyed nine international laboratories to determine if the characteristics or transplant outcomes of allogeneic stem cell donations differed in the immediate periods before and after the switch to routine cryopreservation. RESULTS: Nine centers on two continents provided data for 72 HSC donations just before, and 71 just after, switching to cryopreservation for allogeneic HSC products. No statistically significant differences between the period before and after cryopreservation were noted for time from product collection to receipt, product temperature at receipt, or CD34+ cell viability at receipt. There was an indication of slower absolute neutrophil count recovery after cryopreservation was required (mean time of 15 vs. 17.6 days). DISCUSSION: While there were no apparent changes to most parameters studied, there was an indication of slower neutrophil engraftment that will need to be examined in larger, longer term studies.


Assuntos
COVID-19 , Transplante de Células-Tronco Hematopoéticas , Humanos , COVID-19/terapia , Células-Tronco Hematopoéticas , Pandemias , Transplante Homólogo
2.
Cytotherapy ; 22(6): 337-342, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32223996

RESUMO

BACKGROUND AIMS: At the frontier of transfusion medicine and transplantation, the field of cellular therapy is emerging. Most novel cellular therapy products are produced under investigational protocols with no clear standardization across cell processing centers. Thus, the purpose of this study was to uncover any variations in manufacturing practices for similar cellular therapy products across different cell processing laboratories worldwide. METHODS: An exploratory survey that was designed to identify variations in manufacturing practices in novel cellular therapy products was sent to cell processing laboratory directors worldwide. The questionnaire focused on the manufacturing life cycle of different cell therapies (i.e., collection, purification, in vitro expansion, freezing and storage, and thawing and washing), as well as the level of regulations followed to process each product type. RESULTS: The majority of the centers processed hematopoietic progenitor cells (HPCs) from peripheral blood (n = 18), bone marrow (n = 16) or cord blood (n = 19), making HPCs the most commonly processed cells. The next most commonly produced cellular therapies were lymphocytes (n = 19) followed by mesenchymal stromal cells (n = 14), dendritic cells (n = 9) and natural killer (NK) cells (n = 9). A minority of centers (<5) processed pancreatic islet cells (n = 4), neural cells (n = 3) and induced-pluripotent stem cells (n = 3). Thirty-two laboratories processed products under an investigational status, for either phase I/II (n = 27) or phase III (n = 17) clinical trials. If purification methods were used, these varied for the type of product processed and by institution. Environmental monitoring methods also varied by product type and institution. CONCLUSION: This exploratory survey shows a wide variation in cellular therapy manufacturing practices across different cell processing laboratories. A better understanding of the effect of these variations on the quality of these cell-based therapies will be important to assess for further process evaluation and development.


Assuntos
Biotecnologia/métodos , Terapia Baseada em Transplante de Células e Tecidos/métodos , Biotecnologia/normas , Medula Óssea , Sangue Fetal , Células-Tronco Hematopoéticas , Humanos , Células Matadoras Naturais , Laboratórios/normas , Células-Tronco Mesenquimais
3.
EJHaem ; 1(1): 208-218, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35847689

RESUMO

To obtain a qualitative as well as quantitative view immune reconstitution following umbilical cord blood (UCB) transplantation of paediatric patients, we utilised a broad panel of flow cytometry markers to monitor the phenotypes of lymphoid and myeloid cells at 1-12 months post-transplant. Samples were received from 46 patients with a median age of 3.3 years and survival was 76% at 1 year. Monocytes were at similar or higher median levels than in adult controls at all times tested, with a high CD16+ proportion in the first 3 months. NK cells were also within adult ranges, with a CD56++ high proportion in the first 6 months. B cell recovery was seen from 2 months in most patients and T cells from 3 months, both were delayed with anti-thymocyte globulin (ATG) treatment. CD4:CD8 ratios were high in the first 6 months, and the proportion of T cells with recent thymic emigrant and naïve phenotypes rose from 3 months. NK and plasmacytoid dendritic cell numbers remained at reduced levels in patients not surviving to 1 year. Our results can serve as a useful reference for detailed monitoring of immune reconstitution in paediatric recipients of UCB.

4.
Cochrane Database Syst Rev ; 1: CD009768, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30697701

RESUMO

BACKGROUND: Recipients of allogeneic haematopoietic stem cell transplants (HSCT) can develop acute or chronic, or both forms of graft-versus-host disease (a/cGvHD), whereby immune cells of the donor attack host tissues. Steroids are the primary treatment, but patients with severe, refractory disease have limited options and a poor prognosis. Mesenchymal stromal cells (MSCs) exhibit immunosuppressive properties and are being tested in clinical trials for their safety and efficacy in treating many immune-mediated disorders. GvHD is one of the first areas in which MSCs were clinically applied, and it is important that the accumulating evidence is systematically reviewed to assess whether their use is favoured. OBJECTIVES: To determine the evidence for the safety and efficacy of MSCs for treating immune-mediated inflammation post-transplantation of haematopoietic stem cells. SEARCH METHODS: We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (CENTRAL, the Cochrane Library 2018, Issue 12), MEDLINE (from 1946), Embase (from 1974), CINAHL (from 1937), Web of Science: Conference Proceedings Citation Index-Science (CPCI-S) (from 1990) and ongoing trial databases to 6 December 2018. No constraints were placed on language or publication status. SELECTION CRITERIA: We included RCTs of participants with a haematological condition who have undergone an HSCT as treatment for their condition and were randomised to MSCs (intervention arm) or no MSCs (comparator arm), to prevent or treat GvHD. We also included RCTs which compared different doses of MSCs or MSCs of different sources (e.g. bone marrow versus cord). We included MSCs co-transplanted with haematopoietic stem cells as well as MSCs administered post-transplantation of haematopoietic stem cells. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane.We employed a random-effects model for all analyses due to expected clinical heterogeneity arising from differences in participant characteristics and interventions. MAIN RESULTS: We identified 12 completed RCTs (879 participants), and 13 ongoing trials (1532 enrolled participants planned). Of 12 completed trials, 10 compared MSCs versus no MSCs and two compared different doses of MSCs. One trial was in people with thalassaemia major, the remaining trials were for haematological malignancies. Seven trials administered MSCs to prevent GvHD, whereas five trials gave MSCs to treat GvHD.In the comparison of MSCs with no MSCs, cells were administered at a dose of between 105 and 107 cells/kg in either a single dose (six trials) or in multiple doses (four trials) over a period of three days to four months. The dose-comparison trials compared 2 x 106 cells/kg with 8 x 106 cells/kg in two infusions, or 1 x 106 cells/kg with 3 x 106 cells/kg in a single infusion.The median duration of follow-up in seven trials which administered MSCs prophylactically ranged from 10 to 60 months. In three trials of MSCs as treatment for aGvHD, participants were followed up for 90 or 100 days. In two trials of MSCs as treatment for cGvHD, the mean duration of follow-up was 13.4 months (MSC group) and 23.6 months (control group) in one trial, and 56 weeks in the second trial. Five trials included adults only, six trials included adults and children, and one trial included children only. In eight trials which reported the gender distribution, the percentage of females ranged from 20% to 59% (median 35.8%).The overall quality of the included studies was low: randomisation methods were poorly reported and several of the included studies were subject to a high risk of performance bias and reporting bias. One trial which started in 2008 has not been published and the progress of this trial in unknown, leading to potential publication bias. The quality of evidence was therefore low or very low for all outcomes due to a high risk of bias as well as imprecision due to the low number of overall participants, and in some cases evidence based on a single study. We found that MSCs may make little or no difference in the risk of all-cause mortality in either prophylactic trials (HR 0.85, 95% CI 0.50 to 1.42; participants = 301; studies = 5; I2 = 34% ; low-quality evidence) or therapeutic trials (HR 1.12, 95% CI 0.80 to 1.56; participants = 244; studies = 1; very low-quality evidence), and no difference in the risk of relapse of malignant disease (prophylactic trials: RR 1.08, 95% CI 0.73 to 1.59; participants = 323; studies = 6; I2 = 0%; low-quality evidence) compared with no MSCs. MSCs were well-tolerated, no infusion-related toxicity or ectopic tissue formation was reported. No study reported health-related quality of life. In prophylactic trials, MSCs may reduce the risk of chronic GvHD (RR 0.66, 95% CI 0.49 to 0.89; participants = 283; studies = 6; I2 = 0%; low-quality evidence). This means that only 310 (95% CI 230 to 418) in every 1000 patients in the MSC arm are expected to develop chronic GvHD compared to 469 in the control arm. However, MSCs may make little or no difference to the risk of aGvHD (RR 0.86, 95% CI 0.63 to 1.17; participants = 247; studies = 6; I2 = 0%; low-quality evidence). In GvHD therapeutic trials, we are very uncertain whether MSCs improve complete response of either aGvHD (RR 1.16, 95% CI 0.79 to 1.70, participants = 260, studies = 1; very low-quality evidence) or cGvHD (RR 5.00, 95%CI 0.75 to 33.21, participants = 40, studies = 1; very low-quality evidence).In two trials which compared different doses of MSCs, we found no evidence of any differences in outcomes. AUTHORS' CONCLUSIONS: MSCs are an area of intense research activity, and an increasing number of trials have been undertaken or are planned. Despite a number of reports of positive outcomes from the use of MSCs for treating acute GvHD, the evidence to date from RCTs has not supported the conclusion that they are an effective therapy. There is low-quality evidence that MSCs may reduce the risk of cGvHD. New trial evidence will be incorporated into future updates of this review, which may better establish a role for MSCs in the prevention or treatment of GvHD.


Assuntos
Doença Enxerto-Hospedeiro/terapia , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Mesenquimais , Talassemia beta/terapia , Doença Aguda , Doença Crônica , Doença Enxerto-Hospedeiro/epidemiologia , Neoplasias Hematológicas/mortalidade , Humanos , Incidência , Transplante de Células-Tronco Mesenquimais/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva
5.
Transfusion ; 58(9): 2184-2191, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30204955

RESUMO

BACKGROUND: Viability testing is a common practice in laboratories. The goal of this study was to ascertain current laboratory practices internationally for performing viability testing for cryopreserved cord blood (CB) products and glean information about how to standardize the method to improve interlaboratory reproducibility. STUDY DESIGN AND METHODS: A survey to evaluate current laboratory practices for viability testing was designed and distributed internationally. The question topics included sampling and testing methods, responses to unexpected results, and the rating of the reliability of the CB quality tests, together with expectations for standardization. RESULTS: There were 32 respondents to the survey, of whom 28 responded to the more detailed questionnaire about viability methods. Overall, responses indicated that various stains were used among the laboratories, and when multiple sites used the same viability stain the methods differed. The majority of the respondents were in favor of standardizing the viability testing methods. A wide variety of preferences were communicated about how to standardize the method, but a majority did advocate the use of 7-aminoactinomycin D (7-AAD) with flow cytometry. CONCLUSIONS: The survey results revealed a variety of tests and inconsistent interlaboratory practices for performing the viability assay. Flow cytometry with a 7-AAD dye was suggested as a first step toward standardization.


Assuntos
Preservação de Sangue/métodos , Segurança do Sangue , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Criopreservação/métodos , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Núcleo Celular/ultraestrutura , Separação Celular/métodos , Sobrevivência Celular , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Transplante de Células-Tronco de Sangue do Cordão Umbilical/normas , Dactinomicina/análogos & derivados , Citometria de Fluxo/métodos , Corantes Fluorescentes , Pesquisas sobre Atenção à Saúde , Células-Tronco Hematopoéticas/ultraestrutura , Humanos , Recém-Nascido , Cooperação Internacional , Internet , Laboratórios/normas , Utilização de Procedimentos e Técnicas , Reprodutibilidade dos Testes
6.
Immunotherapy ; 8(12): 1405-1416, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28000538

RESUMO

Mesenchymal stromal cells (MSC) are connective tissue progenitor cells with interesting immunoregulatory properties and are currently being assessed as cellular therapeutics in a variety of clinical applications. While bone marrow has been the traditional source, adipose tissue and umbilical cord are being used increasingly to generate MSC for therapeutic use as an allogeneic, off-the-shelf product. Although the means by which MSC home to sites of inflammation or tissue damage and exert their beneficial effects remain to be fully elucidated, they have recently been shown to adsorb a number of immunosuppressive and anticancer drugs that may further enhance their therapeutic potential.


Assuntos
Células da Medula Óssea/fisiologia , Inflamação/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Neoplasias/terapia , Tecido Adiposo/citologia , Animais , Humanos , Terapia de Imunossupressão , Cordão Umbilical/citologia
7.
Cytotherapy ; 17(9): 1188-99, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26276002

RESUMO

BACKGROUND AIMS: Multipotent mesenchymal stromal cells (MSCs) are distinguished by their ability to differentiate into a number of stromal derivatives of interest for regenerative medicine, but they also have immunoregulatory properties that are being tested in a number of clinical settings. METHODS: We show that brief incubations with rapamycin, everolimus, FK506 or cyclosporine A increase the immunosuppressive potency of MSCs and other cell types. RESULTS: The treated MSCs are up to 5-fold more potent at inhibiting the induced proliferation of T lymphocytes in vitro. We show that this effect probably is due to adsorption of the drug by the MSCs during pre-treatment, with subsequent diffusion into co-cultures at concentrations sufficient to inhibit T-cell proliferation. MSCs contain measurable amounts of rapamycin after a 15-min exposure, and the potentiating effect is blocked by a neutralizing antibody to the drug. With the use of a pre-clinical model of acute graft-versus-host disease, we demonstrate that a low dose of rapamycin-treated but not untreated umbilical cord-derived MSCs significantly inhibit the onset of disease. CONCLUSIONS: The use of treated MSCs may achieve clinical end points not reached with untreated MSCs and allow for infusion of fewer cells to reduce costs and minimize potential side effects.


Assuntos
Doença Enxerto-Hospedeiro/prevenção & controle , Tolerância Imunológica/efeitos dos fármacos , Imunossupressores/farmacologia , Transplante de Células-Tronco Mesenquimais/métodos , Sirolimo/farmacologia , Animais , Anticorpos Neutralizantes/imunologia , Proliferação de Células/efeitos dos fármacos , Técnicas de Cocultura , Ciclosporina/farmacologia , Modelos Animais de Doenças , Everolimo/farmacologia , Feminino , Doença Enxerto-Hospedeiro/imunologia , Humanos , Terapia de Imunossupressão/métodos , Ativação Linfocitária/imunologia , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Sirolimo/imunologia , Linfócitos T/imunologia , Tacrolimo/farmacologia , Cordão Umbilical/citologia
8.
J Immunol ; 185(11): 6617-23, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20980628

RESUMO

Mesenchymal stromal cells (MSCs) may be derived from a variety of tissues, with human umbilical cord (UC) providing an abundant and noninvasive source. Human UC-MSCs share similar in vitro immunosuppressive properties as MSCs obtained from bone marrow and cord blood. However, the mechanisms and cellular interactions used by MSCs to control immune responses remain to be fully elucidated. In this paper, we report that suppression of mitogen-induced T cell proliferation by human UC-, bone marrow-, and cord blood-MSCs required monocytes. Removal of monocytes but not B cells from human adult PBMCs (PBMNCs) reduced the immunosuppressive effects of MSCs on T cell proliferation. There was rapid modulation of a number of cell surface molecules on monocytes when PBMCs or alloantigen-activated PBMNCs were cultured with UC-MSCs. Indomethacin treatment significantly inhibited the ability of UC-MSCs to suppress T cell proliferation, indicating an important role for PGE(2). Monocytes purified from UC-MSC coculture had significantly reduced accessory cell and allostimulatory function when tested in subsequent T cell proliferation assays, an effect mediated in part by UC-MSC PGE(2) production and enhanced by PBMNC alloactivation. Therefore, we identify monocytes as an essential intermediary through which UC-MSCs mediate their suppressive effects on T cell proliferation.


Assuntos
Comunicação Celular/imunologia , Proliferação de Células , Regulação para Baixo/imunologia , Células-Tronco Mesenquimais/imunologia , Monócitos/imunologia , Subpopulações de Linfócitos T/imunologia , Cordão Umbilical/imunologia , Células Cultivadas , Técnicas de Cocultura , Reagentes de Ligações Cruzadas/metabolismo , Dinoprostona/biossíntese , Dinoprostona/fisiologia , Sangue Fetal/citologia , Sangue Fetal/imunologia , Sangue Fetal/metabolismo , Humanos , Teste de Cultura Mista de Linfócitos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Monócitos/citologia , Monócitos/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Células Estromais/citologia , Células Estromais/imunologia , Células Estromais/metabolismo , Subpopulações de Linfócitos T/citologia , Cordão Umbilical/citologia , Cordão Umbilical/metabolismo
9.
Int J Health Care Qual Assur ; 23(4): 422-35, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20535910

RESUMO

PURPOSE: The purpose of this paper is to examine the role of service user and carer involvement in NHS research and describe the nature of this involvement in three specialist mental health Trusts. It also aims to discuss the value of service user and carer involvement and present the perspective of the service user and research manager. DESIGN/METHODOLOGY/APPROACH: The paper reviews patient and public involvement policy and practice in the NHS and NHS research. It examines the effectiveness of involvement activity and utilises a case example to demonstrate the impact of patient/service user involvement on the NHS and the individuals who take part. FINDINGS: The paper concludes that service user involvement is essential if research is to support the development of health services that clearly reflect the needs of the service user and impact positively on service quality. PRACTICAL IMPLICATIONS: Service user involvement is an established element of NHS research and development at both national and local level. The Department of Health strategy for research, Best Research for Best Health, reiterates both the importance of research that benefits the patient and the involvement of the service user in the research process. Despite this, the changes in Department of Health support funding for research, introduced by the strategy, may inadvertently lead to some NHS Trusts experiencing difficulty in resourcing this important activity. ORIGINALITY/VALUE: The paper illustrates the effectiveness of successful patient and public involvement in research. It also identifies how involvement has developed in a fragmented and uncoordinated way and how it is threatened by a failure to embed it more consistently in research infrastructure.


Assuntos
Cuidadores , Pesquisa sobre Serviços de Saúde/organização & administração , Participação do Paciente/métodos , Medicina Estatal/organização & administração , Comportamento Cooperativo , Humanos , Política Pública , Apoio à Pesquisa como Assunto , Reino Unido
10.
Cytotherapy ; 11(6): 738-48, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19878060

RESUMO

BACKGROUND: Mesenchymal stromal cells (MSC) are of clinical interest for their potential use in regenerative medicine and immunotherapy. Originally derived from bone marrow (BM), MSC have now been isolated from most tissues, including umbilical cord (UC) and UC blood (UCB). If MSC from UC are biologically equivalent to those from BM, they would be attractive as a readily available and non-invasive source for cellular therapies. METHODS: Sections of UC were separated into vascular and Wharton's jelly (WJ) fractions, which were then digested individually to release MSC that were isolated by plastic adherence in a 10% fetal calf serum (FCS) medium, or a low serum medium designed for multipotent adult progenitor cells (MAPC). The resulting perivascular (PV) and WJ MSC lines were assayed for expression of characteristic markers and differentiation and immunosuppressive properties. RESULTS: MSC lines were readily derived from most UC tested. Cells grown in MAPC medium (MM) tended to be smaller and more elongated and expressed more nestin, but did not differ substantially in their growth rate, expression of other markers and differentiation capacity. All UC lines tested were adipogenic but poorly osteogenic, and were equivalent in their ability to suppress T-cell proliferation induced by phytohemagglutinin (PHA), activation beads and allostimulation. CONCLUSIONS: UC is a convenient, efficient source of MSC that can be expanded under low serum conditions for application on future studies of tissue regeneration and immunosuppression.


Assuntos
Antígenos CD/metabolismo , Diferenciação Celular , Células-Tronco Mesenquimais/fisiologia , Cordão Umbilical/citologia , Adipogenia/fisiologia , Separação Celular , Humanos , Células-Tronco Mesenquimais/citologia , Osteogênese/fisiologia , Células Estromais/fisiologia
11.
Exp Neurol ; 216(2): 439-48, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19320003

RESUMO

Exploitation of the ability of stem cells to protect damaged neuronal tissue may be a more viable strategy than cell replacement for repair of the central nervous system (CNS). In this study we assessed the capacity of human umbilical cord blood (hUCB)-derived mesenchymal stromal cells (MSCs) to protect and promote regeneration of axotomised neurons within the rat optic system. The optic tract of neonatal rats was transected at the level of the lateral geniculate nucleus, and MSCs were introduced into the lesion site. MSCs survived well up to 2 weeks after grafting, and did not migrate significantly or differentiate. In the presence of MSC grafts, host axonal processes were found to be present in the lesion site, and there was stimulation of an endogenous neural precursor population. Four weeks after grafting, retrograde tracer experiments demonstrated that grafted MSCs, as well as cells of a human fibroblast line, exerted a neuroprotective effect, rescuing a significant percentage of axotomised retinal ganglion cells (RGCs). Further experiments with retrograde and anterograde tracers strongly indicated that MSCs could also promote re-growth of axotomised RGCs to their target, the superior colliculus (SC). Further analysis showed that hUCB-derived MSCs secreted several immunomodulatory and neurotrophic factors in vitro, including TGFbeta1, CNTF, NT-3 and BDNF, which are likely to play a role in neuroprotection. Our data indicate that hUCB-derived MSCs may be an easily accessible, widely available source of cells that can contribute towards neural repair through rescue and regeneration of injured neurons.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Regeneração Nervosa/fisiologia , Traumatismos do Nervo Óptico/patologia , Traumatismos do Nervo Óptico/terapia , Amidinas , Animais , Animais Recém-Nascidos , Axotomia/métodos , Movimento Celular/fisiologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática/métodos , Sangue Fetal/citologia , Fibroblastos/fisiologia , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas de Fluorescência Verde/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Antígeno Ki-67/metabolismo , Regeneração Nervosa/genética , Ratos , Ratos Sprague-Dawley , Células Ganglionares da Retina/fisiologia , Fatores de Tempo , Tubulina (Proteína)/metabolismo
12.
J Neurotrauma ; 26(7): 1147-56, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19203229

RESUMO

We investigated the ability of a population of rat neural stem and precursor cells derived from rat embryonic spinal cord to protect injured neurons in the rat central nervous system (CNS). The neonatal rat optic pathway was used as a model of CNS injury, whereby retinal ganglion cells (RGCs) were axotomized by lesion of the lateral geniculate nucleus one day after birth. Neural stem and precursor cells derived from expanded neurospheres (NS) were transplanted into the lesion site at the time of injury. Application of Fast Blue tracer dye to the lesion site demonstrated that significant numbers of RGCs survived at 4 and 8 weeks in animals that received a transplant, with an average of 28% survival, though in some individual cases survival was greater than 50%. No RGCs survived in animals that received a lesion alone. Furthermore, labeled RGCs were also observed when Fast Blue was applied to the superior colliculus (SC) at 4 weeks, suggesting that neurosphere cells also facilitated RGC to regenerate to their normal target. Transplanted cells did not migrate or express neural markers after transplantation, and secreted several neurotrophic factors in vitro. We conclude that NS cells can protect injured CNS neurons and promote their regeneration. These effects are not attributable to cell replacement, and may be mediated via secretion of neurotrophic factors. Thus, neuroprotection by stem cell populations may be a more viable approach for treatment of CNS disorders than cell replacement therapy.


Assuntos
Axônios/fisiologia , Diferenciação Celular/fisiologia , Regeneração Nervosa/fisiologia , Células Ganglionares da Retina/fisiologia , Animais , Axotomia , Sobrevivência Celular/fisiologia , Células-Tronco Embrionárias , Ensaio de Imunoadsorção Enzimática , Imuno-Histoquímica , Nervo Óptico/fisiologia , Ratos , Ratos Sprague-Dawley , Transplante de Células-Tronco
13.
Transfusion ; 49(5): 953-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19175554

RESUMO

BACKGROUND: A serious constraint in the investigation of the human platelet antigen (HPA) status of potential neonatal alloimmune thrombocytopenia (NAIT) cases is the limited amount of DNA available from the neonates. Whole genome amplification (WGA) of these DNA samples could overcome this problem, but requires validation to ensure that it is sufficiently sensitive and accurate before its application in a clinical diagnostic setting. STUDY DESIGN AND METHODS: This study has validated the use of WGA DNA for HPA-1, -2, -3, -4, -5, and -15 genotyping with a panel of six controls and 13 previously HPA-typed samples from neonates together with parental DNA, using a 5'-nuclease (TaqMan) assay. WGA was performed using titrated amounts of genomic and WGA DNA template. HPA typing was performed on genomic and amplified DNA using a 5'-nuclease assay or polymerase chain reaction with sequence-specific primers (PCR-SSP). RESULTS: WGA DNA yields were in the suggested range of 400x to 800x, as assessed by spectrophotometry and gel analysis, and did not require further purification. HPA genotyping showed 100 percent concordance when using down to 5 ng of genomic or WGA template. CONCLUSION: This study demonstrates that WGA can be used for HPA typing using PCR-SSP or plate-based 5'-nuclease assays. The use of WGA for HPA typing in clinical samples from NAIT patients was validated with 100 percent concordance, and it is suggested that this technology can be used for other analyses where DNA amounts are limited.


Assuntos
Antígenos de Plaquetas Humanas/genética , Técnicas de Amplificação de Ácido Nucleico/normas , Trombocitopenia Neonatal Aloimune/diagnóstico , Primers do DNA , Genoma Humano , Genótipo , Humanos , Recém-Nascido , Técnicas de Amplificação de Ácido Nucleico/métodos , Kit de Reagentes para Diagnóstico
14.
Transfusion ; 49(1): 57-63, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18954395

RESUMO

BACKGROUND: The outcome of clinical transplantation and a number of disease susceptibilities show very strong associations with genetic variants within the major histocompatibility complex, particularly in the human leukocyte antigen (HLA) genes. A problem with many association studies is the lack of sufficient DNA to perform multiple genetic analyses, particularly with transplantation outcomes where donor and recipient DNA are often in short supply. This study assesses whether a multiple-strand displacement whole genome amplification (WGA) method could generate sufficient template of high quality to perform unbiased amplification for analysis of the HLA-A, -B, -C, -DRB1, and -DQB1 genes. STUDY DESIGN AND METHODS: A panel of DNA samples from various biological sources was subjected to WGA reaction using Phi29 DNA polymerase. The HLA genotypes were subsequently determined using standard polymerase chain reaction (PCR)-based methods including sequence-specific oligonucleotide probes (PCR-SSOP, Luminex, Luminex Corp.) and sequence-based typing (PCR-SBT). WGA products and original DNA samples were used to determine the sensitivity of the Luminex assay; in addition, reamplified WGA products were also genotyped. RESULTS: The WGA templates, as well as serially amplified DNA for two successive rounds, yielded HLA genotypes fully concordant with those determined for the original DNA samples. WGA products and original DNA gave reproducible HLA-DQB1 genotypes with 100 to 10 ng of template. Purification of the WGA products was required for successful PCR-SBT, but not for the PCR-SSOP method. CONCLUSION: Our study suggests that WGA can be a reliable method for generating unlimited DNA for medium- or high-resolution HLA typing using the techniques described above.


Assuntos
Genoma Humano , Teste de Histocompatibilidade/métodos , Reação em Cadeia da Polimerase/métodos , Genótipo , Humanos , Sensibilidade e Especificidade
15.
J Neurosci Res ; 86(9): 1902-15, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18338797

RESUMO

We investigated the neurogenic potential of full-term human umbilical cord blood (hUCB)-derived multipotent mesenchymal stem cells (MSCs) in response to neural induction media or coculture with rat neural cells. Phenotypic and functional changes were assessed by immunocytochemistry, RT-PCR, and whole-cell patch-clamp recordings. Naive MSCs expressed both mesodermal and ectodermal markers prior to neural induction. Exposure to retinoic acid, basic fibroblast growth factor, or cyclic adenosine monophosphate (cAMP) did not stimulate neural morphology, whereas exposure to dibutyryl cAMP and 3-isobutyl-1-methylxanthine stimulated a neuron-like morphology but also appeared to be cytotoxic. All protocols stimulated increases in expression of the neural precursor marker nestin, but expression of mature neuronal or glial markers MAP2 and GFAP was not observed. Nestin expression increases were serum level dependent. Electrophysiological properties of MSCs were studied with whole-cell patch-clamp recordings. The MSCs possessed no ionic currents typical of neurons before or after neural induction protocols. Coculture of hUCB-derived MSCs and rat neural cells induced some MSCs to adopt an astrocyte-like morphology and express GFAP protein and mRNA. Our data suggest hUCB-derived MSCs do not transdifferentiate into mature functioning neurons in response to the above neurogenic protocols; however, coculture with rat neural cells led to a minority adopting an astrocyte-like phenotype.


Assuntos
Sangue Fetal/citologia , Células-Tronco Mesenquimais/fisiologia , Células-Tronco Pluripotentes/fisiologia , 1-Metil-3-Isobutilxantina/farmacologia , Animais , Bucladesina/farmacologia , Meios de Cultivo Condicionados , AMP Cíclico/fisiologia , Primers do DNA , Fator 2 de Crescimento de Fibroblastos/farmacologia , Citometria de Fluxo , Humanos , Recém-Nascido , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Proteínas do Tecido Nervoso/genética , Neurônios/citologia , Neurônios/fisiologia , Técnicas de Patch-Clamp , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/efeitos dos fármacos , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medula Espinal/efeitos dos fármacos , Medula Espinal/embriologia , Tretinoína/farmacologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-15974504

RESUMO

PURPOSE: There are many examples of consumer involvement in NHS research but few studies have examined the impact of this on service development or the research process. This study, involving service user and carer researchers working alongside professional researchers, aimed to examine the development of one service user and carer research group in a mental health Trust. DERSIGN/METHODOLOGY/APPROACH: The research involved a review of existing literature on consumer involvement in research, a review of user involvement in research in South West Yorkshire Mental Health NHS Trust, a survey of consumers and NHS staff in the Trust, and a skills audit and training needs analysis of consumers. FINDINGS: The study identified the range and extent of consumer involvement and the impact of this on consumers and the Trust. Service users and carers were involved in a range of projects, mainly on the level of consultation or collaboration. The benefits for consumers were principally on a personal level and included gaining knowledge and experience, improved sense of well-being, self esteem, and confidence. The benefit for the Trust was in having a service user perspective and focus. However, there is a tendency to omit service users from planning and setting priorities. PRACTICAL IMPLICATIONS: The study pointed to the need to build the evidence base on consumer involvement in research, particularly in terms of how consumers can impact on setting research priorities and selecting appropriate methods. It identifies the need for more training for consumers and for NHS staff and for a more coherent strategy. ORIGINALITY/VALUE: This article will be of value to anyone who is at the start or in the early stages of their journey of consumer involvement. It identifies some of the practical issues faced by consumers and staff in working collaboratively, but also points to the benefits for all the stakeholders.


Assuntos
Pesquisa sobre Serviços de Saúde/organização & administração , Participação do Paciente , Comportamento Cooperativo , Humanos , Serviços de Saúde Mental , Pesquisa , Medicina Estatal , Reino Unido
17.
J Pathol ; 196(1): 85-90, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11748646

RESUMO

Immune and inflammatory human renal disease is associated with heavy mononuclear cell infiltration. The trafficking of these cells to extravascular sites is directed by local production of chemokines. Fractalkine is the first described cell-surface anchored chemokine and has potent mononuclear cell-directed adhesion and chemotactic properties. The purpose of this study was to analyse the expression and distribution of fractalkine in human renal inflammation. In situ hybridization and immunohistochemistry were used to study renal biopsies from 15 patients with predominant glomerular inflammation (vasculitic glomerulonephritis) and 15 with predominant tubular and interstitial inflammation (acute renal allograft rejection). Controls comprised non-inflammatory glomerulonephritis and normal tissue. Fractalkine mRNA was predominantly expressed in the major compartment, glomerular or tubulointerstitial, affected by disease and with the strongest expression localized to vascular sites local to inflammation. In acute renal allograft rejection, there was increased expression of fractalkine mRNA by tubular epithelial cells. There was no expression of fractalkine by infiltrating leukocytes and there was only sparse expression in control tissue. Fractalkine mRNA expression correlated with infiltrating leukocyte subsets. Immunohistochemistry confirmed this pattern of expression, with serial section co-localization showing fractalkine expression in areas with macrophage (CD68+) and T cell (CD3+) infiltrates. These expression patterns show that fractalkine is a strong candidate for directing mononuclear cell infiltration in human renal inflammation.


Assuntos
Quimiocinas CX3C/metabolismo , Glomerulonefrite/metabolismo , Rejeição de Enxerto/metabolismo , Transplante de Rim , Proteínas de Membrana/metabolismo , Vasculite/metabolismo , Doença Aguda , Anticorpos Anticitoplasma de Neutrófilos/análise , Doenças Autoimunes/metabolismo , Quimiocina CX3CL1 , Quimiocinas CX3C/genética , Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Hibridização In Situ , Proteínas de Membrana/genética , RNA Mensageiro/genética
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