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1.
Tumour Virus Res ; 16: 200269, 2023 12.
Article de Anglais | MEDLINE | ID: mdl-37499979

RÉSUMÉ

PROBLEM: Human papillomavirus infection is integral to developing invasive cervical cancer in the majority of patients. In a recent genome-wide association study, rs9357152 and rs4243652 have been associated with seropositivity for HPV16 or HPV18, respectively. It is unknown whether these variants also associate with cervical cancer triggered by either HPV16 or HPV18. METHODS: We investigate whether the two HPV susceptibility variants show association with type-specific cervical cancer in a genetic case-control study with cases stratified by HPV16 or HPV18, respectively. We further tested whether rs9357152 modulates gene expression of any of 36 genes at the human leukocyte antigen locus in 256 cervical tissues. RESULTS: rs9357152 was associated with invasive HPV16-positive cervical cancer (OR 1.33, 95%CI 1.03-1.70, p = 0.03), and rs4243652 was associated with HPV18-positive adenocarcinomas (OR 2.96, 95%CI 1.18-7.41, p = 0.02). These associations remained borderline significant after testing against different sets of controls. rs9357152 was found to be an eQTL for HLA-DRB1 in HPV-positive cervical tissues (pANOVA = 0.0009), with the risk allele lowering mRNA levels. CONCLUSIONS: We find evidence that HPV seropositivity variants at chromosome 6 and 14 may modulate type-specific cervical cancer risk. rs9357152 may exert its effect through regulating HLA-DRB1 induction in the presence of HPV. In regard of multiple testing, these results need to be confirmed in larger studies.


Sujet(s)
Infections à papillomavirus , Tumeurs du col de l'utérus , Femelle , Humains , Tumeurs du col de l'utérus/génétique , Chaines HLA-DRB1/génétique , Infections à papillomavirus/complications , Études cas-témoins , Étude d'association pangénomique , Papillomavirus humain de type 16/génétique , Papillomavirus humain de type 18/génétique , Génomique
2.
Front Psychiatry ; 13: 947903, 2022.
Article de Anglais | MEDLINE | ID: mdl-36072460

RÉSUMÉ

The number of wars in the world is on the rise. A number of studies have documented the devastating impact on the public and especially public mental health. Health care systems in low- and lower-middle income countries that are frequently already challenged by the existing mental health services gap cannot provide the necessary care for those displaced by war with existing services. This is especially the case in the Kurdistan Region of Iraq (KRI) after the invasion of the terror organization ISIS in 2014. Most projects in post-conflict areas focus on short term basic psychological services and do not contribute to sustainable long-term capacity building of mental health services. An "Institute for Psychotherapy and Psychotraumatology" was therefore founded in order to train local specialists on a professional level with evidence-based methods adapted to culture and create sustainable long-term structures for psychotherapeutic treatment in the KRI. To achieve this, a number of measures were implemented, including the creation of a "Master of Advanced Studies of Psychotherapy and Psychotraumatology" in collaboration with local communities and the regional University. Two cohorts of students have successfully finished the master's program and a third cohort are expected to graduate in 2023. Improving the capacity of local health care services to provide low-barrier, professional psychotherapeutic care in post-conflict regions supported by the innovative model presented in this article can be expected to improve the burden of psychological problems and contribute to peacebuilding.

3.
Psychother Psychosom Med Psychol ; 72(11): 473-480, 2022 Nov.
Article de Allemand | MEDLINE | ID: mdl-35504296

RÉSUMÉ

The diagnosis of Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS), a rare variant of female sexual development, is usually made during puberty. The uncertainty in self-image and the impos-sibility of becoming pregnant often lead to considerable stress. Although psychosomatic support is consistently recommended in the literature, there have been only a few studies on the psychological aspects of MRKHS. The aim of the present study is to investigate the quality of life or distress of women with MRKHS undergoing neovaginal surgery and, on the other hand, to evaluate effects of the intervention for support during treatment. Methods In an explorative quasi-experimental pre-post study at a national centre for neovaginal surgery, all patients were offered a psychosomatic intervention (intervention group IG, n=23) and their sexual function (FSFI), psychological distress (PHQ-D) and health-related quality of life (SF-12) were assessed before surgery (t0) and six months after (t1). These were compared with data from a sample collected before and after the intervention period (comparison group VG, n=30). Results While the physical quality of life (SF-12) of both groups was unremarkable at both time points, there was a significant impairment in the psychological quality of life. Both groups (IG, VG) improved from t0 to t1 in their sexual function (FSFI) and showed lower depression scores (PHQ-D). The specific intervention developed was well accepted by those affected and rated as helpful. However, this subjectively perceived effectiveness of the intervention was not reflected by improvement on the quality of life scale (SF-12) and depression scale (PHQ-D). Conclusion Those affected show a clear, clinically relevant distress (SF-12), but this is not reflected in the form of psychological comorbidity (PHQ-D). This apparent discrepancy points to psychologically stable women with acute distress due to the diagnosis of variant sex de-evolution. For them, a low-threshold support service with a supportive character seems to be necessary and helpful during the surgical treatment. The reconstructive therapy for the creation of a neovagina seems to have a positive influence on the psychological quality of life. The fact that pregnancy is still not possible due to the missing uterus could be a reason for not reaching the quality of life of the average population.


Sujet(s)
Troubles du développement sexuel de sujets 46, XX , Malformations , Femelle , Humains , Qualité de vie , Vagin/chirurgie , Troubles du développement sexuel de sujets 46, XX/psychologie , Troubles du développement sexuel de sujets 46, XX/chirurgie , Canaux de Müller/chirurgie , Malformations/chirurgie , Malformations/psychologie
4.
Viruses ; 13(11)2021 10 24.
Article de Anglais | MEDLINE | ID: mdl-34834949

RÉSUMÉ

(1) Background: Equine arteritis virus (EAV) infection causes reproductive losses and systemic vasculitis in susceptible equidae. The intact male becomes the virus' reservoir upon EAV infection, as it causes a chronic-persistent infection of the accessory sex glands. Infected semen is the main source of virus transmission. (2) Here, we describe acute EAV infection and spread in a stallion population after introduction of new members to the group. (3) Conclusions: acute clinical signs, acute phase detection of antigen via (PCR) nasal swabs or (EDTA) blood, and seroconversion support the idea of transmission via seminal fluids into the respiratory tract(s) of others. This outbreak highlights EAV's horizontal transmission via the respiratory tract. This route should be considered in a chronic-persistently infected herd, when seronegative animals are added to the group.


Sujet(s)
Infections à artérivirus/épidémiologie , Infections à artérivirus/médecine vétérinaire , Épidémies de maladies , Equartevirus , Maladies des chevaux/épidémiologie , Animaux , Infections à artérivirus/transmission , Infections à artérivirus/virologie , Transmission de maladie infectieuse , Maladies des chevaux/virologie , Equus caballus , Mâle , Masturbation , Infection persistante , Appareil respiratoire/virologie , Sperme/virologie
5.
Gene Ther ; 28(9): 560-571, 2021 09.
Article de Anglais | MEDLINE | ID: mdl-33846552

RÉSUMÉ

Clinical development of chimeric antigen receptor (CAR)-T-cell therapy has been enabled by advances in synthetic biology, genetic engineering, clinical-grade manufacturing, and complex logistics to distribute the drug product to treatment sites. A key ambition of the CARAMBA project is to provide clinical proof-of-concept for virus-free CAR gene transfer using advanced Sleeping Beauty (SB) transposon technology. SB transposition in CAR-T engineering is attractive due to the high rate of stable CAR gene transfer enabled by optimized hyperactive SB100X transposase and transposon combinations, encoded by mRNA and minicircle DNA, respectively, as preferred vector embodiments. This approach bears the potential to facilitate and expedite vector procurement, CAR-T manufacturing and distribution, and the promise to provide a safe, effective, and economically sustainable treatment. As an exemplary and novel target for SB-based CAR-T cells, the CARAMBA consortium has selected the SLAMF7 antigen in multiple myeloma. SLAMF7 CAR-T cells confer potent and consistent anti-myeloma activity in preclinical assays in vitro and in vivo. The CARAMBA clinical trial (Phase-I/IIA; EudraCT: 2019-001264-30) investigates the feasibility, safety, and anti-myeloma efficacy of autologous SLAMF7 CAR-T cells. CARAMBA is the first clinical trial with virus-free CAR-T cells in Europe, and the first clinical trial that uses advanced SB technology worldwide.


Sujet(s)
Myélome multiple , Thérapie génétique , Humains , Immunothérapie adoptive , Myélome multiple/thérapie , Famille des molécules de signalisation de l'activation des lymphocytes , Lymphocytes T
7.
Exp Clin Endocrinol Diabetes ; 125(6): 384-391, 2017 Jun.
Article de Anglais | MEDLINE | ID: mdl-28407666

RÉSUMÉ

HbA1c is the most accepted laboratory parameter for the long term observation of glucose control. There is still much of a debate about the use of HbA1c as a metabolic indicator in diabetic patients (DM) on haemodialysis (HD) and erythropoiesis-stimulating agent (ESA) therapy because of the altered erythrocyte turn over in patients with chronic kidney disease and haemodialysis (CKD5D). In 102 CKD5 patients with and without diabetes mellitus, we examined the dose dependent variability in HbA1c and fructosamine levels under haemodialysis and treated with epoetin α (n=48) and a new generation agent with continuous stimulation of methoxy polyethylene glycol epoetin beta (C.E.R.A.; n=54). HbA1c levels were affected by therapy with ESA treatments. ESA dose was inversely correlated with HbA1c and an escalation of 10.000 IU per week induced an estimated decrease of HbA1c of 0.6 percent. In addition, the increase of reticulocyte number as a marker for erythropoiesis was significantly inversely correlated with the increase of ΔHbA1c. ESA treatments had no such effect on the alternative metabolic parameter fructosamine. When compared, both therapeutic agents had comparable success in attaining haemoglobin (Hb) target values. C.E.R.A. showed better correlation and was more effective over a longer dose interval. Our results show that HbA1c levels in patients should be carefully interpreted based on interfering factors. Nevertheless, HbA1c is currently the most consistent parameter for use ascertaining metabolic status of patients suffering from diabetes mellitus.


Sujet(s)
Néphropathies diabétiques , Époétine alfa/administration et posologie , Érythropoïétine/administration et posologie , Fructosamine/sang , Hémoglobine glyquée/métabolisme , Antianémiques/administration et posologie , Polyéthylène glycols/administration et posologie , Dialyse rénale , Insuffisance rénale chronique , Adulte , Sujet âgé , Sujet âgé de 80 ans ou plus , Néphropathies diabétiques/sang , Néphropathies diabétiques/thérapie , Femelle , Humains , Mâle , Adulte d'âge moyen , Insuffisance rénale chronique/sang , Insuffisance rénale chronique/thérapie
8.
Int J Biochem Cell Biol ; 44(7): 1121-32, 2012 Jul.
Article de Anglais | MEDLINE | ID: mdl-22504287

RÉSUMÉ

Freshly isolated human hematopoietic stem and progenitor cells (HSPCs) are small and round cells which upon cultivation adopt a polarized morphology and redistribute certain cell surface antigens. To functionally dissect this polarization process, we addressed impacts of protein synthesis, HSPC trafficking, cytoskeleton organization or lipid raft integrity on the establishment and maintenance of the cell polarity of human HSPCs. Effects on the morphology, sub-cellular distribution of lipid raft-associated molecular polarization markers (Flotillin-1, Flotillin-2, ICAM-3) and in vitro migration capabilities of treated cells were studied. We could distinguish two levels of cellular polarization, a molecular and a morphological level. Our data suggest that protein synthesis, lipid raft integrity and enzymatic activities of PI3K and aPKC are required to organize the molecular cell polarity. The morphological cell polarization process, however, also depends on actin polymerization and rho-GTPase activities. In summary, our data qualify HSPC polarization processes as new pharmaceutical target to interfere with migratory and with homing capabilities of HSPCs.


Sujet(s)
Mouvement cellulaire/physiologie , Cellules souches hématopoïétiques/cytologie , Cellules souches hématopoïétiques/métabolisme , Microdomaines membranaires/métabolisme , Cellules souches/cytologie , Cellules souches/métabolisme , Animaux , Molécules d'adhérence cellulaire/métabolisme , Polarité de la cellule/physiologie , Humains , Immunotransfert , Souris , Souris de lignée NOD
9.
Kidney Int ; 80(5): 483-92, 2011 Sep.
Article de Anglais | MEDLINE | ID: mdl-21508926

RÉSUMÉ

Calcimimetics increase the sensitivity of the parathyroid calcium-sensing receptor to extracellular calcium for efficient control of hyperparathyroidism. Recent studies suggest that there are beneficial effects of calcimimetics beyond the control of bone and mineral homeostasis. Here, we tested whether the calcium-sensing receptor is also expressed and functionally relevant in podocytes. Analysis of microarray data using Gene Set Enrichment Analysis found that the calcimimetic R-568 influenced various pathways related to oxidative stress, cytoskeletal regulation, cell proliferation, and survival in cultured podocytes. R-568 induced a dose- and time-dependent phosphorylation of the ERK1/2-P90RSK-CREB signaling cascade, and induced pro-survival phosphorylation of BAD and Bcl-xl, thus reducing puromycin aminonucleoside (PAN)-induced podocyte apoptosis by half. Moreover, R-568 preserved the actin cytoskeleton in podocytes exposed to PAN and improved recovery from exposure to cytochalasin D, a reversible inhibitor of actin polymerization. In rats, co-administration of R-568 prevented the proteinuria caused by a single dose of PAN and attenuated the glomerulosclerosis and loss of GFR caused by repetitive puromycin treatment. Hence, calcimimetics limit podocyte damage by antiapoptotic and cytoskeleton-stabilizing effects and may constitute a new approach in the prevention and treatment of glomerular disease.


Sujet(s)
Cytosquelette/métabolisme , Glomérulonéphrite segmentaire et focale/traitement médicamenteux , Podocytes/cytologie , Récepteurs-détecteurs du calcium/métabolisme , Dérivés de l'aniline/pharmacologie , Animaux , Calcimimétiques/pharmacologie , Survie cellulaire , Glomérulonéphrite segmentaire et focale/induit chimiquement , Phénéthylamines , Propylamines , Rats , Récepteurs-détecteurs du calcium/physiologie
10.
PLoS One ; 4(12): e8290, 2009 Dec 22.
Article de Anglais | MEDLINE | ID: mdl-20027317

RÉSUMÉ

BACKGROUND: Migration of mature and immature leukocytes in response to chemokines is not only essential during inflammation and host defense, but also during development of the hematopoietic system. Many molecules implicated in migratory polarity show uniform cellular distribution under non-activated conditions, but acquire a polarized localization upon exposure to migratory cues. METHODOLOGY/PRINCIPAL FINDINGS: Here, we present evidence that raft-associated endocytic proteins (flotillins) are pre-assembled in lymphoid, myeloid and primitive hematopoietic cells and accumulate in the uropod during migration. Furthermore, flotillins display a polarized distribution during immunological synapse formation. Employing the membrane lipid-order sensitive probe Laurdan, we show that flotillin accumulation in the immunological synapse is concomittant with membrane ordering in these regions. CONCLUSIONS: Together with the observation that flotillin polarization does not occur in other polarized cell types such as polarized epithelial cells, our results suggest a specific role for flotillins in hematopoietic cell polarization. Based on our results, we propose that in hematopoietic cells, flotillins provide intrinsic cues that govern segregation of certain microdomain-associated molecules during immune cell polarization.


Sujet(s)
Polarité de la cellule , Cellules souches hématopoïétiques/cytologie , Protéines membranaires/métabolisme , Actines/métabolisme , Animaux , Antigènes CD34/métabolisme , Marqueurs biologiques/métabolisme , Différenciation cellulaire/effets des médicaments et des substances chimiques , Mouvement cellulaire/effets des médicaments et des substances chimiques , Polarité de la cellule/effets des médicaments et des substances chimiques , Chimiokine CXCL12/pharmacologie , Cytosquelette/effets des médicaments et des substances chimiques , Cytosquelette/métabolisme , Chiens , Cellules épithéliales/cytologie , Cellules épithéliales/effets des médicaments et des substances chimiques , Cellules épithéliales/métabolisme , Facteur de stimulation des colonies de granulocytes et de macrophages/pharmacologie , Cellules souches hématopoïétiques/effets des médicaments et des substances chimiques , Humains , Synapses immunologiques/effets des médicaments et des substances chimiques , Synapses immunologiques/métabolisme , Microdomaines membranaires/effets des médicaments et des substances chimiques , Microdomaines membranaires/métabolisme , Monocytes/cytologie , Monocytes/effets des médicaments et des substances chimiques , Transport des protéines/effets des médicaments et des substances chimiques , Pseudopodes/effets des médicaments et des substances chimiques , Pseudopodes/métabolisme , Lymphocytes T/cytologie , Lymphocytes T/effets des médicaments et des substances chimiques
11.
Cell Cycle ; 6(18): 2201-4, 2007 Sep 15.
Article de Anglais | MEDLINE | ID: mdl-17671435

RÉSUMÉ

Hematopoietic stem cells (HSC) are undifferentiated cells, which self-renew over a long period of time and give rise to committed hematopoietic progenitor cells (HPC) containing the capability to replenish the whole blood system. Since both uncontrolled expansion as well as loss of HSC would be fatal, the decision of self-renewal versus differentiation needs to be tightly controlled. There is good evidence that both HSC niches as well as asymmetric cell divisions are involved in controlling whether HSC self-renew or become committed to differentiate. In this context, we recently identified four proteins which frequently segregate asymmetrically in dividing HSC/HPC. Remarkably, three of these proteins, the tetraspanins CD53 and CD63, and the transferrin receptor are endosome-associated proteins. Here, we highlight these observations in conjunction with recent findings in model organisms which show that components of the endosomal machinery are involved in cell-fate specification processes.


Sujet(s)
Division cellulaire , Endosomes , Cellules souches hématopoïétiques/cytologie , Animaux , Division cellulaire/physiologie , Endosomes/physiologie , Cellules souches hématopoïétiques/physiologie , Humains , Cellules souches/cytologie , Cellules souches/physiologie
12.
J Biotechnol ; 131(1): 27-33, 2007 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-17624461

RÉSUMÉ

Phototrophic organisms use photosynthesis to convert solar energy into chemical energy. In nature, the chemical energy is stored in a diverse range of biopolymers. These sunlight-derived, energy-rich biopolymers can be converted into environmentally clean and CO(2) neutral fuels. A select group of photosynthetic microorganisms have developed the ability to extract and divert protons and electrons derived from water to chloroplast hydrogenase(s) to produce molecular H(2) fuel. Here, we describe the development and characterization of C. reinhardtii strains, derived from the high H(2) production mutant Stm6, into which the HUP1 (hexose uptake protein) hexose symporter from Chlorella kessleri was introduced. The isolated cell lines can use externally supplied glucose for heterotrophic growth in the dark. More importantly, external glucose supply (1mM) was shown to increase the H(2) production capacity in strain Stm6Glc4 to approximately 150% of that of the high-H(2) producing strain, Stm6. This establishes the foundations for a new fuel production process in which H(2)O and glucose can simultaneously be used for H(2) production. It also opens new perspectives on future strategies for improving bio-H(2) production efficiency under natural day/night regimes and for using sugar waste material for energy production in green algae as photosynthetic catalysts.


Sujet(s)
Chlamydomonas reinhardtii/génétique , Chlamydomonas reinhardtii/métabolisme , Génome de protozoaire/génétique , Hydrogène/métabolisme , Transporteurs de monosaccharides/génétique , Symporteurs/génétique , Animaux , Métabolisme glucidique/effets des médicaments et des substances chimiques , Division cellulaire/effets des médicaments et des substances chimiques , Chlamydomonas reinhardtii/cytologie , Chlamydomonas reinhardtii/effets des médicaments et des substances chimiques , Obscurité , Vecteurs génétiques , Glucose/pharmacologie , Processus hétérotrophes/effets des médicaments et des substances chimiques , Transformation génétique/effets des médicaments et des substances chimiques
13.
Blood ; 109(12): 5494-501, 2007 Jun 15.
Article de Anglais | MEDLINE | ID: mdl-17332245

RÉSUMÉ

The findings that many primitive human hematopoietic cells give rise to daughter cells that adopt different cell fates and/or show different proliferation kinetics suggest that hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) can divide asymmetrically. However, definitive experimental demonstration is lacking due to the current absence of asymmetrically segregating marker molecules within the primitive hematopoietic cell compartment. Thus, it remains an open question as to whether HSCs/HPCs have the capability to divide asymmetrically, or whether the differences that have been observed are established by extrinsic mechanisms that act on postmitotic progenitors. Here, we have identified 4 proteins (CD53, CD62L/L-selectin, CD63/lamp-3, and CD71/transferrin receptor) that segregate differentially in about 20% of primitive human hematopoietic cells that divide in stroma-free cultures. Therefore, this indicates for the first time that HSCs/HPCs have the capability to divide asymmetrically. Remarkably, these proteins, in combination with the surrogate stem-cell marker CD133, help to discriminate the more primitive human cultivated HSCs/HPCs. Since 3 of these proteins, the transferrin receptor and the tetraspanins CD53 and CD63, are endosomal-associated proteins, they may provide a link between the endosomal compartment and the process of asymmetric cell division within the HSC/HPC compartment.


Sujet(s)
Compartimentation cellulaire , Division cellulaire , Cellules souches hématopoïétiques/cytologie , Protéines/métabolisme , Antigènes CD , Antigènes de différenciation des lymphocytes T , Marqueurs biologiques , Cellules cultivées , Endosomes , Cellules souches hématopoïétiques/métabolisme , Humains , Sélectine L , Glycoprotéines de membrane plaquettaire , Transport des protéines , Récepteurs à la transferrine , Antigène CD53 , Antigène CD63
14.
J Virol ; 80(17): 8718-28, 2006 Sep.
Article de Anglais | MEDLINE | ID: mdl-16912319

RÉSUMÉ

The expression of the proteins encoded by human papillomaviruses (HPVs) is tightly linked to the differentiation program of the infected keratinocytes. The late promoter, expressing the structural proteins, becomes activated in the differentiated keratinocytes, while the early promoter is also active in the basal layers. We have shown previously that the viral transcriptional regulator E2 and the cellular coactivator p300 cooperate in activation of gene expression of HPV8, which infects the skin and is associated with epidermodysplasia verruciformis. Here we demonstrate that this activation is further stimulated after overexpression of the E6 oncoprotein of HPV8 (8E6). RNase protection experiments revealed that 8E6 efficiently cooperates with 8E2 and p300 in activation of the late promoter. In addition, the early promoter, which did not respond to 8E2 and/or p300, was stimulated more than fourfold by 8E6. Our data suggest that both promoters are activated via distinct mechanisms, since the activation of the early promoter was achieved by the N-terminal moiety of 8E6; in contrast, its C-terminal half was sufficient for late promoter activation. This was markedly reduced by the deletion of amino acids 132 to 136 of 8E6, which also abolished the binding to p300, indicating that a direct interaction between 8E6 and p300 is involved. Moreover, a 45-amino-acid segment within the C/H3 region of p300 is required for 8E6 to stimulate the coactivator function of p300. Our results demonstrate for the first time that an E6 oncoprotein of HPV directly contributes to the regulation of HPV gene expression.


Sujet(s)
Régulation de l'expression des gènes viraux , Kératinocytes/virologie , Protéines des oncogènes viraux/métabolisme , Papillomaviridae/métabolisme , Régions promotrices (génétique) , Lignée cellulaire , Humains , Mutagenèse dirigée , Protéines des oncogènes viraux/composition chimique , Protéines des oncogènes viraux/génétique , Papillomaviridae/génétique , Transactivateurs/métabolisme , Transfection , Facteurs de transcription CBP-p300/métabolisme
15.
Stem Cells Dev ; 15(2): 278-85, 2006 Apr.
Article de Anglais | MEDLINE | ID: mdl-16646674

RÉSUMÉ

The targeted manipulation of the genetic program of single cells as well as of complete organisms has strongly enhanced our understanding of cellular and developmental processes and should also help to increase our knowledge of primary human stem cells, e.g., hematopoietic stem cells (HSCs), within the next few years. An essential requirement for such genetic approaches is the existence of a reliable and efficient method to introduce genetic elements into living cells. Retro- and lentiviral techniques are efficient in transducing primary human HSCs, but remain labor and time consuming and require special safety conditions, which do not exist in many laboratories. In our study, we have optimized the nucleofection technology, a modified electroporation strategy, to introduce plasmid DNA into freshly isolated human HSC-enriched CD34(+) cells. Using enhanced green fluorescent protein (eGFP)-encoding plasmids, we obtained transfection efficiencies of approximately 80% and a mean survival rate of 50%. Performing functional assays using GFU-GEMM and long-term culture initiating cells (LTC-IC), we demonstrate that apart from a reduction in the survival rate the nucleofection method itself does not recognizably change the short- or long-term cell fate of primitive hematopoietic cells. Therefore, we conclude, the nucleofection method is a reliable and efficient method to manipulate primitive hematopoietic cells genetically.


Sujet(s)
Cellules souches hématopoïétiques/métabolisme , Transfection/méthodes , Antigène AC133 , Chlorométhyl cétones d'acides aminés/pharmacologie , Animaux , Antigènes CD/analyse , Antigènes CD34/analyse , Techniques de culture cellulaire/méthodes , Lignée cellulaire , Prolifération cellulaire/effets des médicaments et des substances chimiques , Séparation cellulaire , Survie cellulaire/effets des médicaments et des substances chimiques , Test clonogénique , Électroporation/méthodes , Érythrocytes/cytologie , Érythrocytes/métabolisme , Sang foetal/cytologie , Cytométrie en flux , Glycoprotéines/analyse , Protéines à fluorescence verte/génétique , Protéines à fluorescence verte/métabolisme , Cellules souches hématopoïétiques/composition chimique , Cellules souches hématopoïétiques/cytologie , Humains , Leucocytes/cytologie , Leucocytes/métabolisme , Microscopie de fluorescence , Peptides/analyse , Cellules stromales/cytologie
16.
Blood ; 107(5): 2146-52, 2006 Mar 01.
Article de Anglais | MEDLINE | ID: mdl-16249381

RÉSUMÉ

It is often predicted that stem cells divide asymmetrically, creating a daughter cell that maintains the stem-cell capacity, and 1 daughter cell committed to differentiation. While asymmetric stem-cell divisions have been proven to occur in model organisms (eg, in Drosophila), it remains illusive whether primitive hematopoietic cells in mammals actually can divide asymmetrically. In our experiments we have challenged this question and analyzed the developmental capacity of separated offspring of primitive human hematopoietic cells at a single-cell level. We show for the first time that the vast majority of the most primitive, in vitro-detectable human hematopoietic cells give rise to daughter cells adopting different cell fates; 1 inheriting the developmental capacity of the mother cell, and 1 becoming more specified. In contrast, approximately half of the committed progenitor cells studied gave rise to daughter cells, both of which adopted the cell fate of their mother. Although our data are compatible with the model of asymmetric cell division, other mechanisms of cell fate specification are discussed. In addition, we describe a novel human hematopoietic progenitor cell that has the capacity to form natural killer (NK) cells as well as macrophages, but not cells of other myeloid lineages.


Sujet(s)
Différenciation cellulaire/physiologie , Cellules souches hématopoïétiques/physiologie , Cellules tueuses naturelles/physiologie , Lymphopoïèse/physiologie , Modèles biologiques , Animaux , Cellules cultivées , Drosophila , Cellules souches hématopoïétiques/cytologie , Humains , Cellules tueuses naturelles/cytologie
17.
Blood ; 104(8): 2332-8, 2004 Oct 15.
Article de Anglais | MEDLINE | ID: mdl-15231568

RÉSUMÉ

During ontogenesis and the entire adult life hematopoietic stem and progenitor cells have the capability to migrate. In comparison to the process of peripheral leukocyte migration in inflammatory responses, the molecular and cellular mechanisms governing the migration of these cells remain poorly understood. A common feature of migrating cells is that they need to become polarized before they migrate. Here we have investigated the issue of cell polarity of hematopoietic stem/progenitor cells in detail. We found that human CD34(+) hematopoietic cells (1) acquire a polarized cell shape upon cultivation, with the formation of a leading edge at the front pole and a uropod at the rear pole; (2) exhibit an amoeboid movement, which is similar to the one described for migrating peripheral leukocytes; and (3) redistribute several lipid raft markers including cholesterol-binding protein prominin-1 (CD133) in specialized plasma membrane domains. Furthermore, polarization of CD34(+) cells is stimulated by early acting cytokines and requires the activity of phosphoinositol-3-kinase as previously reported for peripheral leukocyte polarization. Together, our data reveal a strong correlation between polarization and migration of peripheral leukocytes and hematopoietic stem/progenitor cells and suggest that they are governed by similar mechanisms.


Sujet(s)
Polarité de la cellule/physiologie , Glycoprotéines/métabolisme , Cellules souches hématopoïétiques/cytologie , Cellules souches hématopoïétiques/métabolisme , Lipides membranaires/métabolisme , Microdomaines membranaires/métabolisme , Peptides/métabolisme , Antigène AC133 , Antigènes CD , Antigènes CD34/métabolisme , Marqueurs biologiques , Mouvement cellulaire , Taille de la cellule , Cellules cultivées , Expression des gènes , Glycoprotéines/génétique , Humains , Antigènes CD44/génétique , Antigènes CD44/métabolisme , Peptides/génétique , Phosphatidylinositol 3-kinases/métabolisme , Protéines de fusion recombinantes/génétique , Protéines de fusion recombinantes/métabolisme , Transfection
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