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1.
Cells Tissues Organs ; 212(6): 546-553, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36261026

RESUMO

Umbilical cord blood cells have therapeutic potential for neurological disorders, through a paracrine mechanism of action. A greater understanding of the safety and immunological effects of allogeneic donor cord blood cells in the context of a healthy recipient immune system, such as in cerebral palsy, is needed. This study aimed to determine how quickly donor cord blood cells were cleared from the circulation in children with cerebral palsy who received a single intravenous infusion of 12/12 human leucocyte antigen (HLA)-matched sibling cord blood cells. Twelve participants with cerebral palsy aged 2-12 years received cord blood cell infusions as part of a phase I trial of umbilical blood infusion for cerebral palsy. Digital droplet PCR analysis of DNA copy number variants specific to donor and recipient was used to assess donor DNA clearance at five timepoints post-infusion, a surrogate measure of cell clearance. Donor cells were cleared by 3 months post-infusion in 11/12 participants. When detected, donor DNA was at a fraction of 0.01-0.31% of total DNA with no signs of graft-versus-host disease in any participant. The donor DNA clearance times provided by this study have important implications for understanding the safety of allogeneic cord blood cell infusion for cerebral palsy and translational tissue engineering or regenerative medicine research in other disorders.


Assuntos
Paralisia Cerebral , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Criança , Humanos , Paralisia Cerebral/terapia , DNA , Sangue Fetal
2.
Pediatr Res ; 94(5): 1631-1638, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37380752

RESUMO

Despite considerable advances, there is a need to improve the outcomes of newborn infants, especially related to prematurity, encephalopathy and other conditions. In principle, cell therapies have the potential to protect, repair, or sometimes regenerate vital tissues; and improve or sustain organ function. In this review, we present highlights from the First Neonatal Cell Therapies Symposium (2022). Cells tested in preclinical and clinical studies include mesenchymal stromal cells from various sources, umbilical cord blood and cord tissue derived cells, and placental tissue and membrane derived cells. Overall, most preclinical studies suggest potential for benefit, but many of the cells tested were not adequately defined, and the optimal cell type, timing, frequency, cell dose or the most effective protocols for the targeted conditions is not known. There is as yet no clinical evidence for benefit, but several early phase clinical trials are now assessing safety in newborn babies. We discuss parental perspectives on their involvement in these trials, and lessons learnt from previous translational work of promising neonatal therapies. Finally, we make a call to the many research groups around the world working in this exciting yet complex field, to work together to make substantial and timely progress to address the knowledge gaps and move the field forward. IMPACT: Survival of preterm and sick newborn infants is improving, but they continue to be at high risk of many systemic and organ-specific complications. Cell therapies show promising results in preclinical models of various neonatal conditions and early phase clinical trials have been completed or underway. Progress on the potential utility of cell therapies for neonatal conditions, parental perspectives and translational aspects are discussed in this paper.


Assuntos
Células-Tronco Mesenquimais , Placenta , Recém-Nascido , Lactente , Humanos , Feminino , Gravidez , Recém-Nascido Prematuro
3.
Cytotherapy ; 24(10): 990-998, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35871156

RESUMO

BACKGROUND AND AIMS: The network of public cord blood banks (CBBs) in Australia, known as AusCord, comprises CBBs located in Brisbane, Sydney and Melbourne. A novel comprehensive analysis has been performed to determine whether the cryopreserved, searchable cord blood unit (CBU) inventory of approximately 36 000 units share similar tissue types or haplotypes. METHODS: Human leukocyte antigen (HLA) data was analysed using Microsoft Excel following standardisation of typing data. RESULTS: The analysis has found that the majority of stored, searched and released CBU exhibit a tissue type that is unique within and between the CBBs. Therefore, each collection performed by the CBBs is likely to comprise a tissue type that is not already stored among the total AusCord inventory. HLA alleles (HLA-A*34, HLA-B*56, HLA-DRB1*08:03), which are uncommon in European populations, were associated with Pacific Islander and/or Indigenous Australian populations and confirmed to be more frequent among donors who, when screened, self-identified as these ethnicities. CONCLUSIONS: These data indicate that (i) continued addition of CBU to existing inventories is likely to further increase the HLA diversity and (ii) screening donors for ethnicity or strategically locating collection sites where ethnic minorities reside can successfully result in collection of rare HLA associated with ethnic minority groups for whom finding donors might otherwise be more difficult.


Assuntos
Bancos de Sangue , Sangue Fetal , Austrália , Etnicidade , Antígenos HLA/genética , Humanos , Grupos Minoritários
4.
Cytotherapy ; 24(1): 2-9, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34384698

RESUMO

BACKGROUND AIMS: Umbilical cord blood (UCB) infusion is being investigated as a treatment for a range of neurological conditions, primarily because of its potent immunomodulatory effects mediated via paracrine signaling. Although initial research mainly utilized autologous UCB, allogeneic samples from a sibling or unrelated donor have now become more common. With the use of allogeneic UCB, questions have arisen surrounding the necessity for human leukocyte antigen (HLA) matching, preparative regimens and immunosuppressant drugs. To investigate the safety of allogeneic UCB for the treatment of neurological conditions and the impact of HLA mismatching and immunosuppresion, the authors conducted a systematic review of the safety of allogeneic UCB infusion for neurological conditions. METHODS: A systematic review of published and gray literature was conducted to investigate the safety of allogeneic UCB infusions for neurological conditions. RESULTS: Authors identified 10 studies using allogeneic UCB to treat autism spectrum disorder, cerebral palsy, stroke, traumatic brain injury and various other conditions. A total of 361 participants (with at least 442 UCB infusions) received a range of HLA-matched/untyped allogeneic units and cell doses, with the majority not administered post-infusion immunosuppression. There were no reported serious adverse events definitely or probably related to the allogeneic UCB infusion, nor later potential complications such as graft-versus-host disease or teratoma formation. CONCLUSIONS: Although variability between studies is high, the available data do not identify safety concerns with allogeneic UCB infusion for the treatment of neurological conditions, even with variable HLA matching or no immunosuppression.


Assuntos
Transtorno do Espectro Autista , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Preparações Farmacêuticas , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Sangue Fetal , Doença Enxerto-Hospedeiro/terapia , Humanos
5.
Clin Chem Lab Med ; 59(7): 1279-1288, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-33711214

RESUMO

OBJECTIVES: Children with very short telomeres commonly develop bone marrow failure and other severe diseases. Identifying the individuals with short telomeres can improve outcome of bone marrow transplantation, with accurate diagnosis requiring the use of age-matched reference intervals (RIs). This study aimed to establish RIs for telomere length (TL) in children using three commonly used methods for TL measurement. METHODS: Healthy children aged 30 days to 18 years were recruited for assessment using age as a continuous variable. Venous blood samples were collected and leukocyte TL was measured using terminal restriction fragment (TRF) analysis, quantitative PCR (QPCR) and flow cytometry with fluorescence in situ hybridization (Flow-FISH). Fractional polynomial model and quantile regression were performed to generate continuous RIs. Factors that might contribute to variation in TL, such as gender, were also examined. RESULTS: A total of 212 samples were analyzed. Continuous RIs are presented as functions of age. TRF analysis and QPCR showed significant negative correlation between TL and age (r=-0.28 and r=-0.38, p<0.001). In contrast, Flow-FISH showed no change in TL with age (r=-0.08, p=0.23). Gender did not have significant influence on TL in children. CONCLUSIONS: This study provides three options to assess TL in children by establishing method-specific continuous RIs. Choosing which method to use will depend on several factors such as amount and type of sample available and required sensitivity to age-related change.


Assuntos
Encurtamento do Telômero , Telômero , Criança , Humanos , Hibridização in Situ Fluorescente , Leucócitos , Valores de Referência , Telômero/genética
6.
Int J Mol Sci ; 18(12)2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29244714

RESUMO

Understanding the pathways and regulation of human haematopoiesis, in particular, lymphopoiesis, is vital to manipulation of these processes for therapeutic purposes. However, although haematopoiesis has been extensively characterised in mice, translation of these findings to human biology remains rudimentary. Here, we describe the isolation of three progenitor subsets from human foetal bone marrow that represent differential stages of commitment to the natural killer (NK) cell lineage based on IL-15 responsiveness. We identify CD7 as a marker of IL-15 responsive progenitors in human bone marrow and find that this expression is maintained throughout commitment and maturation. Within the CD7⁺ fraction, we focussed on the lineage potential of three subsets based on CD127 and CD117 expression and observed restricted lymphoid and biased NK cell potential amongst subsets. We further demonstrate the presence of subsets similar in both phenotype and function in umbilical cord blood and the bone marrow of humanised mice, validating these as appropriate sources of progenitors for the investigation of human haematopoiesis. Overall, we describe several stages in the process of lymphopoiesis that will form the basis of investigating the regulators of this process in humans.


Assuntos
Células da Medula Óssea/citologia , Interleucina-15/metabolismo , Células Matadoras Naturais/citologia , Linfopoese/genética , Animais , Antígenos CD7/metabolismo , Diferenciação Celular/genética , Linhagem da Célula/genética , Feto/citologia , Regulação da Expressão Gênica , Humanos , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Subpopulações de Linfócitos/citologia , Subpopulações de Linfócitos/metabolismo , Camundongos , Proteínas Proto-Oncogênicas c-kit/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo
7.
Mol Cancer ; 13: 123, 2014 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-24885794

RESUMO

BACKGROUND: Acute Myeloid Leukaemia (AML) is a highly heterogeneous disease. Studies in adult AML have identified epigenetic changes, specifically DNA methylation, associated with leukaemia subtype, age of onset and patient survival which highlights this heterogeneity. However, only limited DNA methylation studies have elucidated any associations in paediatric AML. METHODS: We interrogated DNA methylation on a cohort of paediatric AML FAB subtype M5 patients using the Illumina HumanMethylation450 (HM450) BeadChip, identifying a number of target genes with p <0.01 and Δß >0.4 between leukaemic and matched remission (n = 20 primary leukaemic, n = 13 matched remission). Amongst those genes identified, we interrogate DLEU2 methylation using locus-specific SEQUENOM MassARRAY® EpiTYPER® and an increased validation cohort (n = 28 primary leukaemic, n = 14 matched remission, n = 17 additional non-leukaemic and cell lines). Following methylation analysis, expression studies were undertaken utilising the same patient samples for singleplex TaqMan gene and miRNA assays and relative expression comparisons. RESULTS: We identified differential DNA methylation at the DLEU2 locus, encompassing the tumour suppressor microRNA miR-15a/16-1 cluster. A number of HM450 probes spanning the DLEU2/Alt1 Transcriptional Start Site showed increased levels of methylation in leukaemia (average over all probes >60%) compared to disease-free haematopoietic cells and patient remission samples (<24%) (p < 0.001). Interestingly, DLEU2 mRNA down-regulation in leukaemic patients (p < 0.05) was independent of the embedded mature miR-15a/16-1 expression. To assess prognostic significance of DLEU2 DNA methylation, we stratified paediatric AML patients by their methylation status. A subset of patients recorded methylation values for DLEU2 akin to non-leukaemic specimens, specifically patients with sole trisomy 8 and/or chromosome 11 abnormalities. These patients also showed similar miR-15a/16-1 expression to non-leukaemic samples, and potential improved disease prognosis. CONCLUSIONS: The DLEU2 locus and embedded miRNA cluster miR-15a/16-1 is commonly deleted in adult cancers and shown to induce leukaemogenesis, however in paediatric AML we found the region to be transcriptionally repressed. In combination, our data highlights the utility of interrogating DNA methylation and microRNA in combination with underlying genetic status to provide novel insights into AML biology.


Assuntos
Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/metabolismo , MicroRNAs/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Supressoras de Tumor/metabolismo , Adolescente , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Criança , Pré-Escolar , Aberrações Cromossômicas , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 8 , Metilação de DNA , Epigênese Genética , Feminino , Loci Gênicos , Humanos , Lactente , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , MicroRNAs/genética , RNA Longo não Codificante , Indução de Remissão , Transdução de Sinais , Transferases , Proteínas Supressoras de Tumor/genética
8.
Cytotherapy ; 21(5S): S1-S2, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31130175
9.
J Paediatr Child Health ; 50(7): 540-4, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24909743

RESUMO

AIM: Umbilical cord blood may have therapeutic benefit in children with cerebral palsy (CP), but further studies are required. On first appearance it seems that Australia is well placed for such a trial because we have excellence in CP research backed by extensive CP registers, and both public and private cord blood banks. We aimed to examine the possibilities of conducting a trial of autologous umbilical cord blood cells (UCBCs) as a treatment for children with CP in Australia. METHODS: Data linkages between CP registers and cord blood banks were used to estimate potential participant numbers for a trial of autologous UCBCs for children with CP. RESULTS: As of early 2013, one Victorian child with CP had cord blood stored in the public bank, and between 1 and 3 children had their cord blood stored at Cell Care Australia (private cord blood bank). In New South Wales, we counted two children on the CP register who had their stored cord blood available in early 2013. We estimate that there are between 10 and 24 children with CP of any type who have autologous cord blood available across Australia. CONCLUSIONS: In nations with small populations like Australia, combined with Australia's relatively low per capita cord blood storage to date, it is not currently feasible to conduct trials of autologous UCBCs for children with CP. Other options must be explored, such as allogeneic UCBCs or prospective trials for neonates at risk of CP.


Assuntos
Bancos de Sangue , Paralisia Cerebral/terapia , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Sangue Fetal , Austrália , Criança , Coleta de Dados , Estudos de Viabilidade , Humanos , Sistema de Registros , Transplante Autólogo
10.
J Thorac Cardiovasc Surg ; 166(6): 1746-1755, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37527726

RESUMO

BACKGROUND: We conducted this phase I, open-label safety and feasibility trial of autologous cord blood (CB) stem cell (CBSC) therapy via a novel blood cardioplegia-based intracoronary infusion technique during the Norwood procedure in neonates with an antenatal diagnosis of hypoplastic left heart syndrome (HLHS). CBSC therapy may support early cardiac remodeling with enhancement of right ventricle (RV) function during the critical interstage period. METHODS: Clinical grade CB mononucleated cells (CBMNCs) were processed to NetCord-FACT International Standards. To maximize yield, CBSCs were not isolated from CBMNCs. CBMNCs were stored at 4 °C (no cryopreservation) for use within 3 days and delivered after each cardioplegia dose (4 × 15 mL). RESULTS: Of 16 patients with antenatal diagnosis, 13 were recruited; of these 13 patients, 3 were not treated due to placental abruption (n = 1) or conditions delaying the Norwood for >4 days (n = 2) and 10 received 644.9 ± 134 × 106 CBMNCs, representing 1.5 ± 1.1 × 106 (CD34+) CBSCs. Interstage mortality was 30% (n = 3; on days 7, 25, and 62). None of the 36 serious adverse events (53% linked to 3 deaths) were related to CBMNC therapy. Cardiac magnetic resonance imaging before stage 2 (n = 5) found an RV mass index comparable to that in an exact-matched historical cohort (n = 22), with a mean RV ejection fraction of 66.2 ± 4.5% and mean indexed stroke volume of 47.4 ± 6.2 mL/m2 versus 53.5 ± 11.6% and 37.2 ± 10.3 mL/m2, respectively. All 7 survivors completed stage 2 and are alive with normal RV function (6 with ≤mild and 1 with moderate tricuspid regurgitation). CONCLUSIONS: This trial demonstrated that autologous CBMNCs delivered in large numbers without prior cryopreservation via a novel intracoronary infusion technique at cardioplegic arrest during Norwood palliation on days 2 to 3 of life is feasible and safe.


Assuntos
Síndrome do Coração Esquerdo Hipoplásico , Procedimentos de Norwood , Gravidez , Recém-Nascido , Humanos , Feminino , Sangue Fetal , Estudos de Viabilidade , Placenta , Procedimentos de Norwood/efeitos adversos , Procedimentos de Norwood/métodos , Síndrome do Coração Esquerdo Hipoplásico/diagnóstico por imagem , Síndrome do Coração Esquerdo Hipoplásico/cirurgia , Terapia Baseada em Transplante de Células e Tecidos , Ventrículos do Coração , Resultado do Tratamento , Estudos Retrospectivos , Cuidados Paliativos
11.
Front Cell Dev Biol ; 10: 835321, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35372371

RESUMO

Many clinical trials are in progress using cells derived from induced pluripotent stem cells (iPSC) for immunotherapies and regenerative medicine. The success of these new therapies is underpinned by the quality of the cell population used to create the iPSC lines, along with the creation of iPSCs in a fully Good Manufacturing Practice (GMP)-compliant environment such that they can be used safely and effectively in the clinical setting. Umbilical cord blood (CB) from public cord blood banks is an excellent source of starting material for creation of iPSCs. All CB units are manufactured under GMP-conditions, have been screened for infectious diseases, with known family and medical history of the donor. Furthermore, the HLA tissue typing is known, thereby allowing identification of CB units with homozygous HLA haplotypes. CB cells are naïve with less exposure to environmental insults and iPSC can be generated with high efficiency. We describe a protocol that can be adopted by those seeking to create clinical-grade iPSC from banked CB. This protocol uses a small volume of thawed CB buffy to first undergo ex-vivo expansion towards erythroid progenitor cells, which are then used for reprogramming using the CytoTune™-iPS 2.0 Sendai Reprogramming Kit. Resultant iPSC lines are tested to confirm pluripotency, genomic integrity, and stability. Cells are maintained in a feeder-free, xeno-free environment, using fully defined, commercially available reagents. Adoption of this protocol, with heed given to tips provided, allows efficient and robust creation of clinical-grade iPSC cell lines from small volumes of cryopreserved CB.

12.
Stem Cells Transl Med ; 11(10): 1052-1060, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36073721

RESUMO

We aim to create a bank of clinical grade cord blood-derived induced pluripotent stem cell lines in order to facilitate clinical research leading to the development of new cellular therapies. Here we present a clear pathway toward the creation of such a resource, within a strong quality framework, and with the appropriate regulatory, government and ethics approvals, along with a dynamic follow-up and re-consent process of cord blood donors from the public BMDI Cord Blood Bank. Interrogation of the cord blood bank inventory and next generation sequencing was used to identify and confirm 18 donors with suitable HLA homozygous haplotypes. Regulatory challenges that may affect global acceptance of the cell lines, along with the quality standards required to operate as part of a global network, are being met by working in collaboration with bodies such as the International Stem Cell Banking Initiative (ISCBI) and the Global Alliance for iPSC Therapies (GAiT). Ethics approval was granted by an Institutional Human Research Ethics Committee, and government approval has been obtained to use banked cord blood for this purpose. New issues of whole-genome sequencing and the relevant donor safeguards and protections were considered with input from clinical genetics services, including the rights and information flow to donors, and commercialization aspects. The success of these processes has confirmed feasibility and utility of using banked cord blood to produce clinical-grade iPSC lines for potential cellular therapies.


Assuntos
Sangue Fetal , Células-Tronco Pluripotentes Induzidas , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Doadores de Sangue , Bancos de Sangue , Consentimento Livre e Esclarecido
13.
BMJ Open ; 10(3): e034974, 2020 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-32152173

RESUMO

INTRODUCTION: Cerebral palsy (CP) is the most common physical disability of childhood but has no cure. Stem cells have the potential to improve brain injury and are proposed as a therapy for CP. However, many questions remain unanswered about the most appropriate cell type, timing of infusions, dose required and associated risks. Therefore, human safety and efficacy trials are necessary to progress knowledge in the field. METHODS AND ANALYSIS: This is a single group study with sample size n=12 to investigate safety of single-dose intravenous 12/12 human leucocyte antigen-matched sibling cord blood cell infusion to children with CP aged 1-16 years without immune suppression. The study is similar to a 3+3 design, where the first two groups of participants have severe CP, and the final six participants include children with all motor severities. Children will be monitored for adverse events and the duration that donor cells are detected. Assessments at baseline, 3 and 12 months will investigate safety and preliminary evidence of change in gross motor, fine motor, cognitive and quality of life outcomes. ETHICS AND DISSEMINATION: Full approval was obtained from The Royal Children's Hospital Human Research Ethics Committee, and a clinical trial notification was accepted by Australia's Therapeutic Goods Administration. Participant guardian informed consent will be obtained before any study procedures. The main results of this study will be submitted for publication in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ACTRN12616000403437, NCT03087110.


Assuntos
Paralisia Cerebral/terapia , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Irmãos , Adolescente , Criança , Pré-Escolar , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Feminino , Humanos , Lactente , Masculino , Índice de Gravidade de Doença
14.
Mol Immunol ; 115: 56-63, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30144957

RESUMO

NK cells are cytotoxic lymphocytes with a key role in limiting tumour metastases. In mice, the NK cell lineage continually expresses high levels of the Inhibitor of DNA-binding 2 (Id2) protein and loss of Id2 is incongruous with their survival due to aberrant E-protein target gene activity. Using novel Id2 and E-protein antibodies that detect both mouse and human proteins, we have extensively characterised Id2 and E-protein expression in murine and human NK cells. We detected clear expression of E2 A and HEB, and to a lesser extent E2-2 in murine NK cells. In contrast HEB appears to be the major E-protein expressed in human NK cells, with minor E2-2 expression and surprisingly, no E2 A detected in primary NK cells nor human NK cell lines. These novel antibodies are also functional in immunofluorescence and immunoprecipitation. Mass spectrometry analysis of Id2 immuno-precipitated from murine NK cells revealed a number of novel associated proteins including several members of the SWI/SNF-related matrix-associated actin-dependent regulator chromatin (SMARC) and Mediator complex (MED) families. Taken together, these data highlight the utility of novel Id2 and E-protein antibodies and caution against mouse models for understanding Id2/E-protein biology in NK cells given their clearly disparate expression patternbetween species.


Assuntos
Anticorpos/imunologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/imunologia , Proteína 2 Inibidora de Diferenciação/imunologia , Células Matadoras Naturais/imunologia , Fator de Transcrição 4/imunologia , Animais , Linhagem Celular , Linhagem da Célula/imunologia , Cromatina/imunologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL
16.
Regen Med ; 13(7): 859-866, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30205750

RESUMO

Use of clinical-grade human induced pluripotent stem cell (iPSC) lines as a starting material for the generation of cellular therapeutics requires demonstration of comparability of lines derived from different individuals and in different facilities. This requires agreement on the critical quality attributes of such lines and the assays that should be used. Working from established recommendations and guidance from the International Stem Cell Banking Initiative for human embryonic stem cell banking, and concentrating on those issues more relevant to iPSCs, a series of consensus workshops has made initial recommendations on the minimum dataset required to consider an iPSC line of clinical grade, which are outlined in this report. Continued evolution of this field will likely lead to revision of these guidelines on a regular basis.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos/normas , Células-Tronco Pluripotentes Induzidas/citologia , Guias de Prática Clínica como Assunto , Controle de Qualidade , Linhagem Celular , Humanos , Células-Tronco Pluripotentes Induzidas/imunologia , Células-Tronco Pluripotentes Induzidas/microbiologia
17.
PLoS One ; 11(10): e0163824, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27736899

RESUMO

AIMS: Telomeres undergo shortening with cell division, accelerated by increased oxidative stress. We aimed to demonstrate shortened telomeres in the offspring of mothers who have diabetes as a consequence of exposure to increased oxidative stress during intrauterine development. METHODS: We examined the level of glycaemia (glucose, HbA1c, fructosamine), oxidative stress (lipid peroxidation) and the levels of antioxidant enzymes (Superoxide dismutase (SOD) and Selenium dependent glutathione peroxidase) and correlate these findings with mean telomere length (TL) in maternal and foetal blood in groups of pregnant women with pre-gestational diabetes (PGD), gestational diabetes (GD) and a euglycaemic control group. RESULTS: Foetal and maternal glucose, maternal HbA1c, and foetal insulin and C-peptide were higher in the PGD group with the GD group being intermediate. Markers of oxidative stress did not vary between groups with the exception of foetal SOD activity that was highest in the GD group. There were no detectable differences in maternal or foetal TL between study groups. An exploratory analysis looking at correlations between glycaemic and oxidative stress parameters and TL revealed a negative correlation between maternal and foetal glucose and TL across the whole study population. This relationship held for the short-term marker of glycaemic control, fructosamine. CONCLUSIONS: We were unable to show significant telomere shortening in the offspring of mothers with PGD or GD. Exploratory analysis revealed a relationship between foetal TL and short-term glycaemia particularly in PGD. It is possible that increased telomerase activity can compensate for long-term increased oxidative stress but not for short-term dysglycaemia.


Assuntos
Diabetes Gestacional/sangue , Sangue Fetal , Recém-Nascido/sangue , Leucócitos/citologia , Encurtamento do Telômero , Biomarcadores/sangue , Glicemia/análise , DNA/genética , Feminino , Sangue Fetal/química , Glutationa Peroxidase/sangue , Hemoglobinas Glicadas/análise , Humanos , Peroxidação de Lipídeos , Masculino , Estresse Oxidativo , Fosfolipídeo Hidroperóxido Glutationa Peroxidase , Gravidez , Superóxido Dismutase/sangue
18.
Oncotarget ; 7(24): 36474-36488, 2016 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-27167335

RESUMO

Telomeric dysfunction is linked to colorectal cancer (CRC) initiation. However, the relationship of normal tissue and tumor telomere lengths with CRC progression, molecular features and prognosis is unclear. Here, we measured relative telomere length (RTL) by real-time quantitative PCR in 90 adenomas (aRTL), 419 stage I-IV CRCs (cRTL) and adjacent normal mucosa (nRTL). Age-adjusted RTL was analyzed against germline variants in telomere biology genes, chromosome instability (CIN), microsatellite instability (MSI), CpG island methylator phenotype (CIMP), TP53, KRAS, BRAF mutations and clinical outcomes. In 509 adenoma or CRC patients, nRTL decreased with advancing age. Female gender, proximal location and the TERT rs2736100 G allele were independently associated with longer age-adjusted nRTL. Adenomas and carcinomas exhibited telomere shortening in 79% and 67% and lengthening in 7% and 15% of cases. Age-adjusted nRTL and cRTL were independently associated with tumor stage, decreasing from adenoma to stage III and leveling out or increasing from stage III to IV, respectively. Cancer MSI, CIMP, TP53, KRAS and BRAF status were not related to nRTL or cRTL. Near-tetraploid CRCs exhibited significantly longer cRTLs than CIN- and aneuploidy CRCs, while cRTL was significantly shorter in CRCs with larger numbers of chromosome breaks. Age-adjusted nRTL, cRTL or cRTL:nRTL ratios were not associated with disease-free or overall survival in stage II/III CRC. Taken together, our data show that both normal mucosa and tumor RTL are independently associated with CRC progression, and highlight divergent associations of CRC telomere length with tumor CIN profiles.


Assuntos
Instabilidade Cromossômica/genética , Neoplasias Colorretais/genética , Mucosa/metabolismo , Telômero/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Progressão da Doença , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/genética
19.
Ann Thorac Surg ; 100(3): 1021-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26209485

RESUMO

BACKGROUND: One potential approach for advancing univentricular heart surgical palliation outcomes is by stem cell therapy to augment right ventricular function and muscle mass. Whether the stem cell-inclusive cord blood mononuclear cells (CBMNCs) are safe to perfuse into the coronary vasculature during neonatal cardiopulmonary bypass (CPB) is unknown. We evaluated the acute safety, functional effects, and fate of human CBMNCs in a novel model of coronary vasculature delivery in a lamb model of infant CPB. METHODS: Neonatal lambs were randomized in blinded fashion to receive control (n = 5) or human CD45(+) CBMNCs (8 × 10(6) cells/kg body weight, n = 7) treatments during CPB. Aortic cross-clamp time was 40 minutes, with maintenance blood cardioplegia delivered every 10 minutes. Pressure-volume indices were used to measure left ventricular function before CPB and 60 minutes after CPB. CBMNCs were assessed by flow cytometry and immunohistochemistry. RESULTS: CBMNC-treated lambs were hemodynamically stable after CPB, with a decline in left ventricular pressure-volume indices similar to controls. The coronary vasculature was patent on microscopy, without evidence of cell aggregates or clots. Human CD45(+) cells were distributed in high abundance within all cardiac regions, predominantly the right atrium and ventricles, and trafficked beyond endothelial cell layers and between myocytes. CD45(+) cells localized at low incidence in the spleen, liver, lungs, and kidneys, but rarely remained in the circulation (<0.1% of infused cells). CONCLUSIONS: Coronary delivery of human CBMNCs during blood-cardioplegic arrest in a lamb model of CPB results in highly abundant myocardial distribution of cells without acute adverse effects on vascular patency and post-CPB cardiac function.


Assuntos
Ponte Cardiopulmonar , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Animais , Animais Recém-Nascidos , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Vasos Coronários , Modelos Animais de Doenças , Distribuição Aleatória , Ovinos
20.
Haematologica ; 89(3): 377-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15020288

RESUMO

Overexpression of telomerase reverse transcriptase (hTERT) can immortalize some primary human mesenchymal cells. We investigated whether retrovirally-mediated expression of hTERT in CD34+ umbilical cord blood (UCB) cells can extend the replicative lifespan of human hematopoietic progenitor cells. Overexpression of hTERT did not immortalize these cells but did lead to enhanced survival of mature hematopoietic cells.


Assuntos
Antígenos CD34/sangue , Proteínas de Ligação a DNA/metabolismo , Sangue Fetal/citologia , Sangue Fetal/enzimologia , Células-Tronco Hematopoéticas/citologia , Telomerase/metabolismo , Divisão Celular , Sobrevivência Celular , Sangue Fetal/imunologia , Células-Tronco Hematopoéticas/enzimologia , Humanos , Retroviridae/fisiologia , Transdução Genética
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