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

How HIV controllers (HICs) maintain undetectable viremia without therapy is unknown. The strong CD8(+) T-cell HIV suppressive capacity found in many,but not all,HICs may contribute to long-lasting viral control. However,other earlier defense mechanisms may be involved. Here,we examined intrinsic HIC cell resistance to HIV-1 infection. After in vitro challenge,monocyte-derived macrophages and anti-CD3-activated CD4(+) T cells from HICs showed low HIV-1 susceptibility. CD4 T-cell resistance was independent of HIV-1 coreceptors and affected also SIVmac infection. CD4(+) T cells from HICs expressed ex vivo higher levels of p21(Waf1/Cip1),which has been involved in the control of HIV-1 replication,than cells from control subjects. However,HIV restriction in anti-CD3-activated CD4(+) T cells and macrophages was not associated with p21 expression. Restriction inhibited accumulation of reverse transcripts,leading to reduction of HIV-1 integrated proviruses. The block could be overcome by high viral inocula,suggesting the action of a saturable mechanism. Importantly,cell-associated HIV-1 DNA load was extremely low in HICs and correlated with CD4(+) T-cell permissiveness to infection. These results point to a contribution of intrinsic cell resistance to the control of infection and the containment of viral reservoir in HICs. View Publication

BACKGROUND Cell-based therapy shows promise in treating peripheral arterial disease (PAD); however,the optimal cell type and long-term efficacy are unknown. In this study,we identified a novel subpopulation of adult progenitor cells positive for CD34 and M-cadherin (CD34/M-cad BMCs) in mouse and human bone marrow. We also examined the long-lasting therapeutic efficacy of mouse CD34/M-cad BMCs in restoring blood flow and promoting vascularization in an atherosclerotic mouse model of PAD. METHODS AND FINDINGS Colony-forming cell assays and flow cytometry analysis showed that CD34/M-cad BMCs have hematopoietic progenitor properties. When delivered intra-arterially into the ischemic hindlimbs of ApoE/ mice,CD34/M-cad BMCs alleviated ischemia and significantly improved blood flow compared with CD34/M-cad BMCs,CD34/M-cad BMCs,or unselected BMCs. Significantly more arterioles were seen in CD34/M-cad cell-treated limbs than in any other treatment group 60 days after cell therapy. Furthermore,histologic assessment and morphometric analyses of hindlimbs treated with GFP CD34/M-cad cells showed that injected cells incorporated into solid tissue structures at 21 days. Confocal microscopic examination of GFP CD34/M-cad cell-treated ischemic legs followed by immunostaining indicated the vascular differentiation of CD34/M-cad progenitor cells. A cytokine antibody array revealed that CD34/M-cad cell-conditioned medium contained higher levels of cytokines in a unique pattern,including bFGF,CRG-2,EGF,Flt-3 ligand,IGF-1,SDF-1,and VEGFR-3,than did CD34/M-cad cell-conditioned medium. The proangiogenic cytokines secreted by CD34/M-cad cells induced oxygen- and nutrient-depleted endothelial cell sprouting significantly better than CD34/M-cad cells during hypoxia. CONCLUSION CD34/M-cad BMCs represent a new progenitor cell type that effectively alleviates hindlimb ischemia in ApoE/ mice by consistently improving blood flow and promoting arteriogenesis. Additionally,CD34/M-cad BMCs contribute to microvascular remodeling by differentiating into vascular cells and releasing proangiogenic cytokines and growth factors. View Publication

Endoplasmic reticulum (ER) stress occurs during early embryonic development. The aim of this study is to determine whether ER stress occurs during human embryonic stem cell differentiation induced by retinoic acid (RA). H9 human embryonic stem cells were subjected to RA treatment for up to 29. days to induce differentiation. HEK293 cells were treated with RA as a control. The results demonstrate that several ER stress-responsive genes are differentially regulated in H9 and HEK293 cells in response to 5. days of RA treatment. GRP78/Bip was upregulated in H9 cells but downregulated in HEK293 cells. eIF2?? was downregulated in H9 cells but not in HEK293 cells. Phosphorylation of eIF2?? was downregulated in H9 cells but upregulated in HEK293 cells. XBP-1 was downregulated immediately after RA treatment in H9 cells,but its downregulation was much slower in HEK293 cells. Additionally,two ER-resident E3 ubiquitin ligases,gp78 and Hrd1,were both upregulated in H9 cells following 5. days of exposure to RA. Moreover,the protein Bcl2 was undetectable in H9 cells and H9-derived cells but was expressed in HEK293 cells,and it expression in the two types of cells was unaltered by RA treatment. In H9 cells treated with RA for 29. days,GRP78/Bip,XBP-1 and Bcl2 were all upregulated. These results suggest that ER stress is involved in H9 cell differentiation induced by RA. ?? 2011 Elsevier Inc. View Publication

The chemical approach to controlling stem cell fates is emerging as a powerful tool,holding great promise in tissue engineering and regenerative medicine. Various small molecules have been demonstrated capable of modulating stem cell differentiation. In this paper,we studied the effects of 5-aminoimidazole-4-carboxamide-1-ß-riboside (AICAR),an activator of AMP-activated protein kinase (AMPK),on mesenchymal stem cells (MSCs). AICAR at high concentrations (1.0-2.0 mM) significantly inhibited proliferation of both human amnion-derived MSCs (hAMSCs) and rabbit bone marrow-derived MSCs (BM-MSCs). Most importantly,AICAR efficiently promoted the osteogenic differentiation of hAMSCs and BM-MSCs in both growth medium and osteogenic medium. However,Metformin,another AMPK activator,showed no such effects. Meanwhile,AICAR significantly inhibited adipogenic differentiation of hAMSCs and BM-MSCs. Our data suggests that AICAR represents a potent molecule,which can be applied in bone tissue regeneration. View Publication

The differentiation of human embryonic stem cells (hESCs) and human-induced pluripotent stem cells (hiPSCs) towards functional neurons particularly hold great potential for the cell-based replacement therapy in neurodegenerative diseases. Here,we describe a stepwise differentiation protocol that mimics the early stage of neural development in human to promote the generation of neuroprogenitors at a high yield. Both the hESCs and hiPSCs are initially cultured in an optimized feeder-free condition,which offer an efficient formation of aggregates. To specify the neuroectodermal specification,these aggregates are differentiated in a defined neural induction medium to develop into neural rosettes-like structures. The rosettes are expanded into free-floating sphere and can be further propagated or developed into variety of neuronal subtypes. View Publication

Human embryonic stem cells (hESCs) hold great promise for regenerative medicine because they can undergo unlimited self-renewal and retain the capability to differentiate into all cell types in the body. Although numerous genes/proteins such as Oct4 and Gata6 have been identified to play critical regulatory roles in self-renewal and differentiation of hESC,the majority of the regulators in these cellular processes and more importantly how these regulators co-operate with each other and/or with epigenetic modifications are still largely unknown. We propose here a systematic approach to integrate genomic and epigenomic data for identification of direct regulatory interactions. This approach allows reconstruction of cell-type-specific transcription networks in embryonic stem cells (ESCs) and fibroblasts at an unprecedented scale. Many links in the reconstructed networks coincide with known regulatory interactions or literature evidence. Systems-level analyses of these networks not only uncover novel regulators for pluripotency and differentiation,but also reveal extensive interplays between transcription factor binding and epigenetic modifications. Especially,we observed poised enhancers characterized by both active (H3K4me1) and repressive (H3K27me3) histone marks that contain enriched Oct4- and Suz12-binding sites. The success of such a systems biology approach is further supported by experimental validation of the predicted interactions. View Publication

DNA double-strand breaks (DSB) are the most cytotoxic lesions induced by topoisomerase II poisons. Nonhomologous end joining (NHEJ) is a major pathway for DSB repair and requires DNA-dependent protein kinase (DNA-PK) activity. DNA-PK catalytic subunit (DNA-PKcs) is structurally similar to PI-3K,which promotes cell survival and proliferation and is upregulated in many cancers. KU-0060648 is a dual inhibitor of DNA-PK and PI-3K in vitro. KU-0060648 was investigated in a panel of human breast and colon cancer cells. The compound inhibited cellular DNA-PK autophosphorylation with IC(50) values of 0.019 $\mu$mol/L (MCF7 cells) and 0.17 $\mu$mol/L (SW620 cells),and PI-3K-mediated AKT phosphorylation with IC(50) values of 0.039 $\mu$mol/L (MCF7 cells) and more than 10 $\mu$mol/L (SW620 cells). Five-day exposure to 1 $\mu$mol/L KU-0060648 inhibited cell proliferation by more than 95{\%} in MCF7 cells but only by 55{\%} in SW620 cells. In clonogenic survival assays,KU-0060648 increased the cytotoxicity of etoposide and doxorubicin across the panel of DNA-PKcs-proficient cells,but not in DNA-PKcs-deficient cells,thus confirming that enhanced cytotoxicity was due to DNA-PK inhibition. In mice bearing SW620 and MCF7 xenografts,concentrations of KU-0060648 that were sufficient for in vitro growth inhibition and chemosensitization were maintained within the tumor for at least 4 hours at nontoxic doses. KU-0060648 alone delayed the growth of MCF7 xenografts and increased etoposide-induced tumor growth delay in both in SW620 and MCF7 xenografts by up to 4.5-fold,without exacerbating etoposide toxicity to unacceptable levels. The proof-of-principle in vitro and in vivo chemosensitization with KU-0060648 justifies further evaluation of dual DNA-PK and PI-3K inhibitors. View Publication

Lymphocyte activation gene-3 (LAG-3) is an inhibitory receptor expressed by CD4+ T cells and tempers their homeostatic expansion. Because CD4+ T cell proliferation is tightly coupled to bioenergetics,we investigate the role of LAG-3 in modulating naive CD4+ T cell metabolism. LAG-3 deficiency enhances the metabolic profile of naive CD4+ T cells by elevating levels of mitochondrial biogenesis. In vivo,LAG-3 blockade partially restores expansion and the metabolic phenotype of wild-type CD4+ T cells to levels of Lag3-/- CD4+ T cells,solidifying that LAG-3 controls these processes. Lag3-/- CD4+ T cells also demonstrate greater signal transducer and activator of transcription 5 (STAT5) activation,enabling resistance to interleukin-7 (IL-7) deprivation. These results implicate this pathway as a target of LAG-3-mediated inhibition. Additionally,enhancement of STAT5 activation,as a result of LAG-3 deficiency,contributes to greater activation potential in these cells. These results identify an additional mode of regulation elicited by LAG-3 in controlling CD4+ T cell responses. View Publication

CD8 T cells can play both a protective and pathogenic role in inflammation and autoimmune development. Recent studies have highlighted the ability of CD8 T cells to function as T follicular helper (Tfh) cells in the germinal center in the context of infection. However,whether this phenomenon occurs in autoimmunity and contributes to autoimmune pathogenesis is largely unexplored. In this study,we show that CD8 T cells acquire a CD4 Tfh profile in the absence of functional regulatory T cells in both the IL-2-deficient and scurfy mouse models. Depletion of CD8 T cells mitigates autoimmune pathogenesis in IL-2-deficient mice. CD8 T cells express the B cell follicle-localizing chemokine receptor CXCR5,a principal Tfh transcription factor Bcl6,and the Tfh effector cytokine IL-21. CD8 T cells localize to the B cell follicle,express B cell costimulatory proteins,and promote B cell differentiation and Ab isotype class switching. These data reveal a novel contribution of autoreactive CD8 T cells to autoimmune disease,in part,through CD4 follicular-like differentiation and functionality. View Publication

Early erythroid progenitors are transit-amplifying cells with high proliferative capacity committed to undergoing red cell differentiation. CD71/CD24low progenitors are less mature and have greater proliferative capacity than CD71/CD24high. We present protocols for isolation of CD71/CD24low progenitors from mouse fetal liver using both fluorescence-activated cell sorting (FACS) and immunomagnetic enrichment. CD71/CD24low progenitors isolated with both approaches show similar transcriptomes at single-cell resolution and exhibit characteristic proliferative responses to glucocorticoids. For complete details on the use and execution of this protocol,please refer to Li et al. (2019). View Publication

Adipose tissue dysfunction is strongly linked to the development of chronic inflammation and cardiometabolic disorders in aging. While much attention has been given to the role of resident adipose tissue immune cells in the disruption of homeostasis in obesity,age-specific effects remain understudied. Here,we identified and characterized a population of ?? T cells,which show unique age-dependent accumulation in the visceral adipose tissue (VAT) of both mice and humans. Diet-induced obesity likewise increased ?? T cell numbers; however,the effect was greater in the aged where the increase was independent of fat mass. ?? T cells in VAT express a tissue-resident memory T cell phenotype (CD44hiCD62LlowCD69+) and are predominantly IL-17A-producing cells. Transcriptome analyses of immunomagnetically purified ?? T cells identified significant age-associated differences in expression of genes related to inflammation,immune cell composition,and adipocyte differentiation,suggesting age-dependent qualitative changes in addition to the quantitative increase. Genetic deficiency of ?? T cells in old age improved the metabolic phenotype,characterized by increased respiratory exchange ratio,and lowered levels of IL-6 both systemically and locally in VAT. Decreased IL-6 was predominantly due to reduced production by non-immune stromal cells,primarily preadipocytes,and adipose-derived stem cells. Collectively,these findings suggest that an age-dependent increase of tissue-resident ?? T cells in VAT contributes to local and systemic chronic inflammation and metabolic dysfunction in aging. View Publication

Immune-mediated red blood cell (RBC) destruction due to antibodies is an ongoing problem in transfusion medicine for the selection of the safest blood. Serological testing often revealed incompatibility with donors' RBCs. When this incompatible blood was transfused,destruction was due mostly to extravascular-mediated phagocytosis of the antibody-opsonized RBCs; however,intravascular hemolysis was sometimes observed without explanation. Based on serology,antibodies with potential for clinical sequalae could not be ascertained; thus,antigen-negative blood was usually selected for transfusion to avoid problems. Antibodies to antigens having very high frequency in the general population (>95%),however,made selection of antigen-negative blood difficult and sometimes impossible. Some patients,who were sensitized by previous transfusions or by pregnancy,developed multiple antibodies,again creating a problem for finding compatible blood for transfusion,without the ability to discern which of the antibodies may be clinically irrelevant and ignored. Transfusion medicine scientists began searching for an in vitro means to determine the in vivo outcome of transfusion of blood that was serologically incompatible. Methods such as chemiluminescence,monocyte-macrophage phagocytosis,and antibody-dependent cellular cytotoxicity (ADCC) were described. Over the years,the monocyte monolayer assay (MMA) has emerged as the most reliable in vitro assay for the prediction of the clinical relevance of a given antibody. ADCC has not been fully studied but has the potential to be useful for predicting which antibodies may result in intravascular hemolysis. This article captures the protocols for the implementation and readout of the MMA and ADCC assays for use in predicting the clinical significance of antibodies in a transfusion setting. {\textcopyright} 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Monocyte monolayer assay (MMA) Basic Protocol 2: Antibody-dependent cellular cytotoxicity assay (ADCC). View Publication