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

Aldehyde dehydrogenase 1A1 (ALDH1A1) activity is used as a marker of breast cancer stem cells; however,little is known about the regulation of ALDH1A1 expression. Mucin 1 (MUC1) is a heterodimeric protein that is aberrantly overexpressed in most human breast cancers. In studies of breast cancer cells stably silenced for MUC1 or overexpressing the oncogenic MUC1-C subunit,we demonstrate that MUC1-C is sufficient for induction of MEK → ERK signaling and that treatment with a MUC1-C inhibitor suppresses ERK activation. In turn,MUC1-C induces ERK-mediated phosphorylation and activation of the CCAAT/enhancer-binding protein β (C/EBPβ) transcription factor. The results further show that MUC1-C and C/EBPβ form a complex on the ALDH1A1 gene promoter and activate ALDH1A1 gene transcription. MUC1-C-induced up-regulation of ALDH1A1 expression is associated with increases in ALDH activity and is detectable in stem-like cells when expanded as mammospheres. These findings demonstrate that MUC1-C (i) activates a previously unrecognized ERK→C/EBPβ→ALDH1A1 pathway,and (ii) promotes the induction of ALDH activity in breast cancer cells. View Publication

TLR-mediated activation of dendritic cells (DCs) is associated with a metabolic transition in which mitochondrial oxidative phosphorylation is inhibited by endogenously synthesized NO and the cells become committed to glucose and aerobic glycolysis for survival. We show that inhibition of mechanistic target of rapamycin (mTOR) extends the lifespan of TLR-activated DCs by inhibiting the induction of NO production,thereby allowing the cells to continue to use their mitochondria to generate ATP,and allowing them the flexibility to use fatty acids or glucose as nutrients to fuel core metabolism. These data provide novel mechanistic insights into how mTOR modulates DC metabolism and cellular longevity following TLR activation and provide an explanation for previous findings that mTOR inhibition enhances the efficacy of DCs in autologous vaccination. View Publication

Imatinib mesylate (IM) induces clinical remissions in chronic-phase chronic myeloid leukemia (CML) patients but IM resistance remains a problem. We recently identified several features of CML CD34(+) stem/progenitor cells expected to confer resistance to BCR-ABL-targeted therapeutics. From a study of 25 initially chronic-phase patients,we now demonstrate that some,but not all,of these parameters correlate with subsequent clinical response to IM therapy. CD34(+) cells from the 14 IM nonresponders demonstrated greater resistance to IM than the 11 IM responders in colony-forming cell assays in vitro (P textless .001) and direct sequencing of cloned transcripts from CD34(+) cells further revealed a higher incidence of BCR-ABL kinase domain mutations in the IM nonresponders (10%-40% vs 0%-20% in IM responders,P textless .003). In contrast,CD34(+) cells from IM nonresponders and IM responders were not distinguished by differences in BCR-ABL or transporter gene expression. Interestingly,one BCR-ABL mutation (V304D),predicted to destabilize the interaction between p210(BCR-ABL) and IM,was detectable in 14 of 20 patients. T315I mutant CD34(+) cells found before IM treatment in 2 of 20 patients examined were preferentially amplified after IM treatment. Thus,2 properties of pretreatment CML stem/progenitor cells correlate with subsequent response to IM therapy. Prospective assessment of these properties may allow improved patient management. View Publication

The β-hemoglobinopathies sickle cell disease and β-thalassemia are among the most common human genetic disorders worldwide. Hemoglobin A2 (HbA2,α₂δ₂) and fetal hemoglobin (HbF,α₂γ₂) both inhibit the polymerization of hemoglobin S,which results in erythrocyte sickling. Expression of erythroid Kruppel-like factor (EKLF) and GATA1 is critical for transitioning hemoglobin from HbF to hemoglobin A (HbA,α₂β₂) and HbA2. The lower levels of δ-globin expression compared with β-globin expression seen in adulthood are likely due to the absence of an EKLF-binding motif in the δ-globin proximal promoter. In an effort to up-regulate δ-globin to increase HbA2 expression,we created a series of EKLF-GATA1 fusion constructs composed of the transactivation domain of EKLF and the DNA-binding domain of GATA1,and then tested their effects on hemoglobin expression. EKLF-GATA1 fusion proteins activated δ-,γ-,and β-globin promoters in K562 cells,and significantly up-regulated δ- and γ-globin RNA transcript and protein expression in K562 and/or CD34(+) cells. The binding of EKLF-GATA1 fusion proteins at the GATA1 consensus site in the δ-globin promoter was confirmed by chromatin immunoprecipitation assay. Our studies demonstrate that EKLF-GATA1 fusion proteins can enhance δ-globin expression through interaction with the δ-globin promoter,and may represent a new genetic therapeutic approach to β-hemoglobinopathies. View Publication

The intricate molecular mechanisms that regulate ESC pluripotency are incompletely understood. Prior research indicated that activation of the Janus kinase-signal transducer and activator of transcription (STAT3) pathway or inhibition of extracellular signal-regulated kinase/glycogen synthase kinase 3 (ERK/GSK3) signaling maintains mouse ESC (mESC) pluripotency. Here,we demonstrate that inhibition of protein kinase C (PKC) isoforms maintains mESC pluripotency without the activation of STAT3 or inhibition of ERK/GSK3 signaling pathways. Our analyses revealed that the atypical PKC isoform,PKCζ plays an important role in inducing lineage commitment in mESCs through a PKCζ-nuclear factor kappa-light-chain-enhancer of activated B cells signaling axis. Furthermore,inhibition of PKC isoforms permits derivation of germline-competent ESCs from mouse blastocysts and also facilitates reprogramming of mouse embryonic fibroblasts toward induced pluripotent stem cells. Our results indicate that PKC signaling is critical to balancing ESC self-renewal and lineage commitment. View Publication

Recent studies using defined transcription factors to convert skin fibroblasts into chondrocytes have raised the question of whether osteo-chondroprogenitors expressing SOX9 and RUNX2 could also be generated during the course of the reprogramming process. Here,we demonstrated that doxycycline-inducible expression of reprogramming factors (KLF4 [K] and c-MYC [M]) for 6 days were sufficient to convert murine fibroblasts into SOX9(+)/RUNX2(+) cellular aggregates and together with SOX9 (S) promoted the conversion efficiency when cultured in a defined stem cell medium,mTeSR. KMS-reprogrammed cells possess gene expression profiles akin to those of native osteo-chondroprogenitors with elevated osteogenic properties and can differentiate into osteoblasts and chondrocytes in vitro,but form bone tissue upon transplantation under the skin and in the fracture site of mouse tibia. Altogether,we provide a reprogramming strategy to enable efficient derivation of osteo-chondrogenic cells that may hold promise for cell replacement therapy not limited to cartilage but also for bone tissues. View Publication

Diminishing homeostatic proliferation of memory T cells is essential for improving the efficacy of lymphoablation in transplant recipients. Our previous studies in a mouse heart transplantation model established that B lymphocytes secreting proinflammatory cytokines are critical for T cell recovery after lymphoablation. The goal of the current study was to identify mediators of B cell activation following lymphoablation in allograft recipients. Transcriptome analysis revealed that macrophage-inducible C-type lectin (Mincle,Clec4e) expression is up-regulated in B cells from heart allograft recipients treated with murine anti-thymocyte globulin (mATG). Recipient Mincle deficiency diminishes B cell production of pro-inflammatory cytokines and impairs T lymphocyte reconstitution. Mixed bone marrow chimeras lacking Mincle only in B lymphocytes have similar defects in T cell recovery. Conversely,treatment with a synthetic Mincle ligand enhances T cell reconstitution after lymphoablation in non-transplanted mice. Treatment with agonistic CD40 mAb facilitates T cell reconstitution in CD4 T cell-depleted,but not in Mincle-deficient,recipients indicating that CD40 signaling induces T cell proliferation via a Mincle-dependent pathway. These findings are the first to identify an important function of B cell Mincle as a sensor of damage-associated molecular patterns released by the graft and demonstrate its role in clinically relevant settings of organ transplantation. View Publication

Huntington’s disease (HD) causes selective degeneration of striatal and cortical neurons,resulting in cell mosaicism of coexisting still functional and dysfunctional cells. The impact of non-cell autonomous mechanisms between these cellular states is poorly understood. Here we generated telencephalic organoids with healthy or HD cells,grown separately or as mosaics of the two genotypes. Single-cell RNA sequencing revealed neurodevelopmental abnormalities in the ventral fate acquisition of HD organoids,confirmed by cytoarchitectural and transcriptional defects leading to fewer GABAergic neurons,while dorsal populations showed milder phenotypes mainly in maturation trajectory. Healthy cells in mosaic organoids restored HD cell identity,trajectories,synaptic density,and communication pathways upon cell-cell contact,while showing no significant alterations when grown with HD cells. These findings highlight cell-type-specific alterations in HD and beneficial non-cell autonomous effects of healthy cells,emphasizing the therapeutic potential of modulating cell-cell communication in disease progression and treatment. Mosaic organoids where pathological and healthy cells are grown together,reveal the rescue of phenotypes in pathological cells due to communication with healthy cells without harming them,as demonstrated by single-cell RNA-sequencing data. View Publication

Although bone marrow-derived cells with high aldehyde dehydrogenase activity (ALDH br ) have shown therapeutic potential against various diseases in animal studies,clinical trials have failed to show concurrent findings. We aimed to clarify the optimal conditions for the efficacy of ALDH br cells by using a murine bleomycin-induced pulmonary fibrosis model. We intravenously transferred male or female donor C57BL/6 mice-derived ALDH br cells into recipient C57BL/6 mice under various conditions,and used mCherry-expressing mice as a donor to trace the transferred ALDH br cells. Pulmonary fibrosis improved significantly when (1) female-derived,not male-derived,and (2) lineage (Lin)-negative,not lineage-positive,ALDH br cells were transferred during the (3) fibrotic,not inflammatory,phase. Consistent with the RNA-sequencing results,female-derived Lin − /ALDH br cells were more resistant to oxidative stress than male-derived cells in vitro,and transferred female-derived Lin − /ALDH br cells were more viable than male-derived cells in the fibrotic lung. The mechanism underlying the antifibrotic effects of Lin − /ALDH br cells was strongly associated with reduction of oxidative stress. Our results indicated that Lin − /ALDH br cell therapy could ameliorate pulmonary fibrosis by reducing oxidative stress and suggested that their efficacy was mediated by sex-related differences. Thus,sex-awareness strategies may be important for clinical application of bone marrow ALDH br cells as a therapeutic tool. The online version contains supplementary material available at 10.1186/s13287-024-03933-8. View Publication

Although acute myeloid leukemia (AML) affects hematopoietic stem cell (HSC)-supportive microenvironment,it is largely unknown whether leukemia-modified bone marrow (BM) microenvironment can be remodeled to support normal hematopoiesis after complete remission (CR). As a key element of BM microenvironment,endothelial progenitor cells (EPCs) provide a feasible way to investigate BM microenvironment remodeling. Here,we find reduced and dysfunctional BM EPCs in AML patients,characterized by impaired angiogenesis and high ROS levels,could be partially remodeled after CR and improved by N-acetyl-L-cysteine (NAC). Importantly,HSC-supporting ability of BM EPCs is partially recovered,whereas leukemia-supporting ability is decreased in CR patients. Mechanistically,the transcriptome characteristics of leukemia-modified BM EPCs return to near-normal after CR. In a classic AML mouse and chemotherapy model,BM vasculature and normal hematopoiesis are reversed after CR. In summary,we provide further insights into how leukemia-modified BM microenvironment can be remodeled to support normal hematopoiesis after CR,which can be further improved by NAC. Subject terms: Translational research,Acute myeloid leukaemia View Publication

Immune checkpoint blockade therapies have shown clinical promise in a variety of cancers,but how tumor-infiltrating T cells are activated remains unclear. In this study,we explore the functions of PD-L1 on dendritic cells (DCs),which highly express PD-L1. We observe that PD-L1 on DC plays a critical role in limiting T cell responses. Type 1 conventional DCs are essential for PD-L1 blockade and they upregulate PD-L1 upon antigen uptake. Upregulation of PD-L1 on DC is mediated by type II interferon. While DCs are the major antigen presenting cells for cross-presenting tumor antigens to T cells,subsequent PD-L1 upregulation protects them from killing by cytotoxic T lymphocytes,yet dampens the antitumor responses. Blocking PD-L1 in established tumors promotes re-activation of tumor-infiltrating T cells for tumor control. Our study identifies a critical and dynamic role of PD-L1 on DC,which needs to be harnessed for better invigoration of antitumor immune responses. View Publication

Antiserum to epithelial membrane antigen and three monoclonal antibodies (MAb) to milk-fat globule membranes immunocytochemically stain only epithelial cells,whereas a fourth reacts also with myoepithelial cells in inter- and intralobular ducts of human breast. Staining with peanut lectin shows a gradual increase for epithelial cells,from little or no staining in ducts through variable staining in ductules to intense staining in secretory alveoli. Antisera and MAb to vimentin,smooth-muscle actin,MAb to the common acute lymphoblastic leukemia antigen and to a glycoprotein of 135 KD stain myoepithelial cells in main ducts,but this staining is reduced in inter- and intralobular ducts and ductules. MAb to epithelial-specific keratin 18 stain a minor population of ductal epithelial cells,the major population of epithelial cells in interlobular (ILD) and extralobular terminal ducts (ETD),and epithelial cells in a minority of ductules. In lactating glands most epithelial cells in ductules are stained,but the alveolar and myoepithelial cells are unstained. Keratin MAb PKK2 and LP34 strongly stain myoepithelial cells,but only a minor population of epithelial cells in main ducts. However,these MAb stain principally the epithelial cells in ILD,ETD,and a minority of ductules. In lactating glands most epithelial cells are stained in ductules,but the myoepithelial and not the alveolar cells are stained intensely in secretory lobules. It is suggested that the unusual staining pattern of cells found principally in the ILD,ETD,and some ductules may represent regions of growth and/or subpopulation(s) of cells intermediate between epithelial and myoepithelial cells. View Publication