搜索结果: 'methocult media formulations for human hematopoietic cells serum containing'

We analyzed 21 children with leukemia receiving haploidentical hematopoietic stem cell transplantation (haplo-HSCT) from killer immunoglobulin (Ig)-like receptors (KIR) ligand-mismatched donors. We showed that,in most transplantation patients,variable proportions of donor-derived alloreactive natural killer (NK) cells displaying anti-leukemia activity were generated and maintained even late after transplantation. This was assessed through analysis of donor KIR genotype,as well as through phenotypic and functional analyses of NK cells,both at the polyclonal and clonal level. Donor-derived KIR2DL1(+) NK cells isolated from the recipient displayed the expected capability of selectively killing C1/C1 target cells,including patient leukemia blasts. Differently,KIR2DL2/3(+) NK cells displayed poor alloreactivity against leukemia cells carrying human leukocyte antigen (HLA) alleles belonging to C2 group. Unexpectedly,this was due to recognition of C2 by KIR2DL2/3,as revealed by receptor blocking experiments and by binding assays of soluble KIR to HLA-C transfectants. Remarkably,however,C2/C2 leukemia blasts were killed by KIR2DL2/3(+) (or by NKG2A(+)) NK cells that coexpressed KIR2DS1. This could be explained by the ability of KIR2DS1 to directly recognize C2 on leukemia cells. A role of the KIR2DS2 activating receptor in leukemia cell lysis could not be demonstrated. Altogether,these results may have important clinical implications for the selection of optimal donors for haplo-HSCT. View Publication

Enteroendocrine cells of the gastrointestinal (GI) tract play a central role in metabolism,digestion,satiety and lipid absorption,yet their development remains poorly understood. Here we show that Arx,a homeodomain-containing transcription factor,is required for the normal development of mouse and human enteroendocrine cells. Arx expression is detected in a subset of Neurogenin3 (Ngn3)-positive endocrine progenitors and is also found in a subset of hormone-producing cells. In mice,removal of Arx from the developing endoderm results in a decrease of enteroendocrine cell types including gastrin-,glucagon/GLP-1-,CCK-,secretin-producing cell populations and an increase of somatostatin-expressing cells. This phenotype is also observed in mice with endocrine-progenitor-specific Arx ablation suggesting that Arx is required in the progenitor for enteroendocrine cell development. In addition,depletion of human ARX in developing human intestinal tissue results in a profound deficit in expression of the enteroendocrine cell markers CCK,secretin and glucagon while expression of a pan-intestinal epithelial marker,CDX2,and other non-endocrine markers remained unchanged. Taken together,our findings uncover a novel and conserved role of Arx in mammalian endocrine cell development and provide a potential cause for the chronic diarrhea seen in both humans and mice carrying Arx mutations. View Publication

There is a medical need for an agent with the positive effects of estrogen on bone and the cardiovascular system,but without the negative effects on reproductive tissue. Raloxifene (LY139481 HCI) is a benzothiophene derivative that binds to the estrogen receptor and inhibits the effects of estrogen on the uterus. In an ovariectomized (OVX) rat model we investigated the effects of raloxifene on bone loss (induced by estrogen deficiency),serum lipids,and uterine tissue. After oral administration of raloxifene for 5 wk (0.1-10 mg/kg per d) to OVX rats,bone mineral density in the distal femur and proximal tibia was significantly greater than that observed in OVX controls (ED50 of 0.03-0.3 mg/kg). Serum cholesterol was lower in the raloxifene-treated animals,which had a minimal effective dose of 0.1 mg/kg and an approximate oral ED50 of 0.2 mg/kg. The effects of raloxifene on bone and serum cholesterol were comparable to those of a 0.1-mg/kg per d oral dose of ethynyl estradiol. Raloxifene diverged dramatically from estrogen in its lack of significant estrogenic effects on uterine tissue. Ethynyl estradiol produced a marked elevation in a number of uterine histologic parameters (e.g.,epithelial cell height,stromal eosinophilia). These data suggest that raloxifene has promise as an agent with beneficial bone and cardiovascular effects in the absence of significant uterine effects. View Publication

INTRODUCTION: Various synthetic bone-graft substitutes are used commercially as osteoconductive scaffolds in the treatment of bone defects and fractures. The role of bone-graft substitutes is changing from osteoconductive conduits for growth to an delivery system for biologic fracture treatments. Achieving optimal bone regeneration requires biologics (e.g. MSC) and using the correct scaffold incorporated into a local environment for bone regeneration. The need for an unlimited supply with high quality bone-graft substitutes continue to find alternatives for bone replacement surgery. MATERIALS AND METHODS: This in vitro study investigates cell seeding efficiency,metabolism,gene expression and growth behaviour of MSC sown on six commercially clinical available bone-graft substitutes in order to define their biological properties: synthetic silicate-substituted porous hydroxyapatite (Actifuse ABX),synthetic alpha-TCP (Biobase),synthetic beta-TCP (Vitoss),synthetic beta-TCP (Chronos),processed human cancellous allograft (Tutoplast) and processed bovines hydroxyapatite ceramic (Cerabone). 250,000 MSC derived from human bone marrow (n=4) were seeded onto the scaffolds,respectively. On days 2,6 and 10 the adherence of MSC (fluorescence microscopy) and cellular activity (MTT assay) were analysed. Osteogenic gene expression (cbfa-1) was analysed by RT-PCR and scanning electron microscopy was performed. RESULTS: The highest number of adhering cells was found on Tutoplast (e.g. day 6: 110.0+/-24.0 cells/microscopic field; ptextless0.05) followed by Chronos (47.5+/-19.5,ptextless0.05),Actifuse ABX (19.1+/-4.4),Biobase (15.7+/-9.9),Vitoss (8.8+/-8.7) and Cerabone (8.1+/-2.2). MSC seeded onto Tutoplast showed highest metabolic activity and gene expression of cbfa-1. These data are confirmed by scanning electron microscopy. The cell shapes varied from round-shaped cells to wide spread cells and cell clusters,depending on the bone-graft substitutes. Processed human cancellous allograft is a well-structured and biocompatible scaffold for ingrowing MSC in vitro. Of all other synthetical scaffolds,beta-tricalcium phosphate (Chronos) have shown the best growth behaviour for MSC. DISCUSSION: Our results indicate that various bone-graft substitutes influence cell seeding efficiency,metabolic activity and growth behaviour of MSC in different manners. We detected a high variety of cellular integration of MSC in vitro,which may be important for bony integration in the clinical setting. View Publication

Ectopic retroviral expression of homeobox B4 (HOXB4) causes an accelerated and enhanced regeneration of murine hematopoietic stem cells (HSCs) and is not known to compromise any program of lineage differentiation. However,HOXB4 expression levels for expansion of human stem cells have still to be established. To test the proposed hypothesis that HOXB4 could become a prime tool for in vivo expansion of genetically modified human HSCs,we retrovirally overexpressed HOXB4 in purified cord blood (CB) CD34+ cells together with green fluorescent protein (GFP) as a reporter protein,and evaluated the impact of ectopic HOXB4 expression on proliferation and differentiation in vitro and in vivo. When injected separately into nonobese diabetic-severe combined immunodeficient (NOD/SCID) mice or in competition with control vector-transduced cells,HOXB4-overexpressing cord blood CD34+ cells had a selective growth advantage in vivo,which resulted in a marked enhancement of the primitive CD34+ subpopulation (P =.01). However,high HOXB4 expression substantially impaired the myeloerythroid differentiation program,and this was reflected in a severe reduction of erythroid and myeloid progenitors in vitro (P textless.03) and in vivo (P =.01). Furthermore,HOXB4 overexpression also significantly reduced B-cell output (P textless.01). These results show for the first time unwanted side effects of ectopic HOXB4 expression and therefore underscore the need to carefully determine the therapeutic window of HOXB4 expression levels before initializing clinical trials. View Publication

The hemopoietic stem cell (HSC) compartment encompasses cell subsets with heterogeneous proliferative and developmental potential. Numerous CD34(-) cell subsets that might reside at an earlier stage of differentiation than CD34(+) HSCs have been described and characterized within human umbilical cord blood (UCB). We identified a novel subpopulation of CD34(-)CD133(-)CD7(-)CD45(dim)lineage (lin)(-) HSCs contained within human UCB that were endowed with low but measurable extended long-term culture-initiating cell activity. Exposure of CD34(-)CD133(-)CD7(-)CD45(dim)lin(-) HSCs to stem cell factor preserved cell viability and was associated with the following: 1) concordant expression of the stem cell-associated Ags CD34 and CD133,2) generation of CFU-granulocyte-macrophage,burst-forming unit erythroid,and megakaryocytic aggregates,3) significant extended long-term culture-initiating cell activity,and 4) up-regulation of mRNA signals for myeloperoxidase. At variance with CD34(+)lin(-) cells,CD34(-)CD133(-)CD7(-)CD45(dim)lin(-) HSCs maintained with IL-15,but not with IL-2 or IL-7,proliferated vigorously and differentiated into a homogeneous population of CD7(+)CD45(bright)CD25(+)CD44(+) lymphoid progenitors with high expression of the T cell-associated transcription factor GATA-3. Although they harbored nonclonally rearranged TCRgamma genes,IL-15-primed CD34(-)CD133(-)CD7(-)CD45(dim)lin(-) HSCs failed to achieve full maturation,as manifested in their CD3(-)TCRalphabeta(-)gammadelta(-) phenotype. Conversely,culture on stromal cells supplemented with IL-15 was associated with the acquisition of phenotypic and functional features of NK cells. Collectively,CD34(-)CD133(-)CD7(-)CD45(dim)lin(-) HSCs from human UCB displayed an exquisite sensitivity to IL-15 and differentiated into lymphoid/NK cells. Whether the transplantation of CD34(-)lin(-) HSCs possessing T/NK cell differentiation potential may impact on immunological reconstitution and control of minimal residual disease after HSC transplantation for autoimmune or malignant diseases remains to be determined. View Publication

Abdominal aortic aneurysm (AAA) is life-threatening,for which efficient nonsurgical treatment strategy has not been available so far. Several previous studies investigating the therapeutic effect of mesenchymal stem cells (MSCs) in AAA indicated that MSCs could inhibit aneurysmal inflammatory responses and extracellular matrix destruction,and suppress aneurysm occurrence and expansion. Vascular smooth muscle cell (VSMC) phenotypic plasticity is reported to be predisposed in AAA initiation and progression. However,little is known about the effect of MSCs on VSMC phenotypic modulation in AAA. In this study,we investigate the therapeutic efficacy of umbilical cord mesenchymal stem cells (UC-MSCs) in elastase-induced AAA model and evaluate the effect of UC-MSC on VSMC phenotypic regulation. We demonstrate that the intravenous injection of UC-MSC attenuates elastase-induced aneurysmal expansion,reduces elastin degradation and fragmentation,inhibits MMPs and TNF-$\alpha$ expression,and preserves and/or restores VSMC contractile phenotype in AAA. Taken together,these results highlight the therapeutic and VSMC phenotypic modulation effects of UC-MSC in AAA progression,which further indicates the potential of applying UC-MSC as an alternative treatment candidate for AAA. View Publication

Integrating viruses represent robust tools for cellular reprogramming; however,the presence of viral transgenes in induced pluripotent stem cells (iPSCs) is deleterious because it holds the risk of insertional mutagenesis leading to malignant transformation. Here,we combine the robustness of lentiviral reprogramming with the efficacy of Cre recombinase protein transduction to derive iPSCs devoid of transgenes. By genome-wide analysis and targeted differentiation towards the cardiomyocyte lineage,we show that transgene-free iPSCs are superior to iPSCs before Cre transduction. Our study provides a simple,rapid and robust protocol for the generation of clinical-grade iPSCs suitable for disease modeling,tissue engineering and cell replacement therapies. View Publication

BACKGROUND Definitive endoderm (DE) is one of the three germ layers which during in vivo vertebrate development gives rise to a variety of organs including liver,lungs,thyroid and pancreas; consequently efficient in vitro initiation of stem cell differentiation to DE cells is a prerequisite for successful cellular specification to subsequent DE-derived cell types [1,2]. In this study we present a novel approach to rapidly and efficiently down regulate pluripotency genes during initiation of differentiation to DE cells by addition of dimethyl sulfoxide (DMSO) to Activin A-based culture medium and report its effects on the downstream differentiation to hepatocyte-like cells. MATERIALS AND METHODS Human embryonic stem cells (hESC) were differentiated to DE using standard methods in medium supplemented with 100ng/ml of Activin A and compared to cultures where DE specification was additionally enhanced with different concentrations of DMSO. DE cells were subsequently primed to generate hepatic-like cells to investigate whether the addition of DMSO during formation of DE improved subsequent expression of hepatic markers. A combination of flow cytometry,real-time quantitative reverse PCR and immunofluorescence was applied throughout the differentiation process to monitor expression of pluripotency (POUF5/OCT4 & NANOG),definitive endoderm (SOX17,CXCR4 & GATA4) and hepatic (AFP & ALB) genes to generate differentiation stage-specific signatures. RESULTS Addition of DMSO to the Activin A-based medium during DE specification resulted in rapid down regulation of the pluripotency genes OCT4 and NANOG,accompanied by an increase expression of the DE genes SOX17,CXCR4 and GATA4. Importantly,the expression level of ALB in DMSO-treated cells was also higher than in cells which were differentiated to the DE stage via standard Activin A treatment. View Publication

Cancer stem cells (CSCs) have been associated with metastasis and therapeutic resistance and can be generated via epithelial mesenchymal transition (EMT). Some studies suggest that the hormone melatonin acts in CSCs and may participate in the inhibition of the EMT. The objectives of this study were to evaluate the formation of mammospheres from the canine and human breast cancer cell lines,CMT-U229 and MCF-7,and the effects of melatonin treatment on the modulation of stem cell and EMT molecular markers: OCT4,E-cadherin,N-cadherin and vimentin,as well as on cell viability and invasiveness of the cells from mammospheres. The CMT-U229 and MCF-7 cell lines were subjected to three-dimensional culture in special medium for stem cells. The phenotype of mammospheres was first evaluated by flow cytometry (CD44+/CD24low/- marking). Cell viability was measured by MTT colorimetric assay and the expression of the proteins OCT4,E-cadherin,N-cadherin and vimentin was evaluated by immunofluorescence and quantified by optical densitometry. The analysis of cell migration and invasion was performed in Boyden Chamber. Flow cytometry proved the stem cell phenotype with CD44+/CD24low/- positive marking for both cell lines. Cell viability of CMT-U229 and MCF-7 cells was reduced after treatment with 1mM melatonin for 24 h (Ptextless0.05). Immunofluorescence staining showed increased E-cadherin expression (Ptextless0.05) and decreased expression of OCT4,N-cadherin and vimentin (Ptextless0.05) in both cell lines after treatment with 1 mM melatonin for 24 hours. Moreover,treatment with melatonin was able to reduce cell migration and invasion in both cell lines when compared to control group (Ptextless0.05). Our results demonstrate that melatonin shows an inhibitory role in the viability and invasiveness of breast cancer mammospheres as well as in modulating the expression of proteins related to EMT in breast CSCs,suggesting its potential anti-metastatic role in canine and human breast cancer cell lines. View Publication

Here,we describe a procedure and first-in-man clinical effects of adoptive transfer of ex vivo expanded CD4+CD25+CD127- T regulatory cells (Tregs) in the treatment of graft versus host disease (GvHD). The cells were sorted from buffy coats taken from two family donors,expanded ex vivo and transferred to respective recipients who suffered from either acute or chronic GvHD. The therapy allowed for significant alleviation of the symptoms and reduction of pharmacologic immunosuppression in the case of chronic GvHD,while in the case of grade IV acute GvHD it only transiently improved the condition,for the longest time within all immunosuppressants used nonetheless. View Publication