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

For antibody-based therapy of cancer,monoclonal antibodies (mAbs) of human origin are superior to mouse,mouse/human chimeric or humanized mAbs,because of their minimum immunogenicity to humans and their efficient collaboration with human effector cells. In the present study,human mAbs were prepared against a pancarcinoma antigen,MK-1 (Ep-CAM),using a genetically-engineered mouse (KM mouse) that contains the human immunoglobulin genes. Spleen cells from KM mice,immunized with recombinant MK-1,were fused with P3-U1 mouse myeloma cells. Of 44 anti-MK-1 clones analyzed,two were of IgG4 and the others of IgM clones. Although the two IgG4 clones were suggested to recognize the same antigenic determinant or two closely located determinants,their VK regions were encoded by different light-chain genes while their VH sequences were identical. The two IgG4 and one of the IgM clones tested revealed antibody-dependent cell-mediated cytotoxicity and complement-dependent cytotoxicity,respectively,against MK-1-expressing cells in vitro,suggesting that these fully human mAbs produced against MK-1 and their V-region genes,which are applicable for the preparation of engineered antibody fragments that may be useful for antibody-based therapy of cancer. View Publication

Germ line mutations in the Adenomatous polyposis coli tumor suppressor gene cause a hereditary form of intestinal tumorigenesis in both mice and man. Here we show that in Apc(Min/+) mice,which carry a heterozygous germ line mutation at codon 850 of Apc,there is progressive loss of immature and mature thymocytes from approximately 80 days of age with complete regression of the thymus by 120 days. In addition,Apc(Min/+) mice show parallel depletion of splenic natural killer (NK) cells,immature B cells,and B progenitor cells in bone marrow due to complete loss of interleukin 7 (IL-7)-dependent B-cell progenitors. Using bone marrow transplantation experiments into wild-type recipients,we have shown that the capacity of transplanted Apc(Min/+) bone marrow cells for T- and B-cell development appears normal. In contrast,although the Apc(Min/+) bone marrow microenvironment supported short-term reconstitution with wild-type bone marrow,Apc(Min/+) animals that received transplants subsequently underwent lymphodepletion. Fibroblast colony-forming unit (CFU-F) colony assays revealed a significant reduction in colony-forming mesenchymal progenitor cells in the bone marrow of Apc(Min/+) mice compared with wild-type animals prior to the onset of lymphodepletion. This suggests that an altered bone marrow microenvironment may account for the selective lymphocyte depletion observed in this model of familial adenomatous polyposis. View Publication

Mice deficient in early B cell factor (EBF) are blocked at the progenitor B cell stage prior to immunoglobulin gene rearrangement. The EBF-dependent block in B cell development occurs near the onset of B-lineage commitment,which raises the possibility that EBF may act instructively to specify the B cell fate from uncommitted,multipotential progenitor cells. To test this hypothesis,we transduced enriched hematopoietic progenitor cells with a retroviral vector that coexpressed EBF and the green fluorescent protein (GFP). Mice reconstituted with EBF-expressing cells showed a near complete absence of T lymphocytes. Spleen and peripheral blood samples were textgreater95 and 90% GFP+EBF+ mature B cells,respectively. Both NK and lymphoid-derived dendritic cells were also significantly reduced compared with control-transplanted mice. These data suggest that EBF can restrict lymphopoiesis to the B cell lineage by blocking development of other lymphoid-derived cell pathways. View Publication

Aldehyde dehydrogenase (ALDH) is an enzyme that is expressed in the liver and is required for the conversion of retinol (vitamin A) to retinoic acids. ALDH is also highly enriched in hematopoietic stem cells (HSCs) and is considered a selectable marker of human HSCs,although its contribution to stem cell fate remains unknown. In this study,we demonstrate that ALDH is a key regulator of HSC differentiation. Inhibition of ALDH with diethylaminobenzaldehyde (DEAB) delayed the differentiation of human HSCs that otherwise occurred in response to cytokines. Moreover,short-term culture with DEAB caused a 3.4-fold expansion in the most primitive assayable human cells,the nonobese diabetic/severe combined immunodeficiency mouse repopulating cells,compared with day 0 CD34(+)CD38(-)lin(-) cells. The effects of DEAB on HSC differentiation could be reversed by the coadministration of the retinoic acid receptor agonist,all-trans-retinoic acid,suggesting that the ability of ALDH to generate retinoic acids is important in determining HSC fate. DEAB treatment also caused a decrease in retinoic acid receptor-mediated signaling within human HSCs,suggesting directly that inhibition of ALDH promotes HSC self-renewal via reduction of retinoic acid activity. Modulation of ALDH activity and retinoid signaling is a previously unrecognized and effective strategy to amplify human HSCs. View Publication

Hematopoietic stem progenitor cells (HSPCs) undergo phenotypical and functional changes during their emergence and development. Although the molecular programs governing the development of human hematopoietic stem cells (HSCs) have been investigated broadly,the relationships between dynamic metabolic alterations and their functions remain poorly characterized. In this study,we comprehensively described the proteomics of HSPCs in the human fetal liver (FL),umbilical cord blood (UCB),and adult bone marrow (aBM). The metabolic state of human HSPCs was assessed via a Seahorse assay,RT‒PCR,and flow cytometry-based metabolic-related analysis. To investigate whether perturbing glutathione metabolism affects reactive oxygen species (ROS) production,the metabolic state,and the expansion of human HSPCs,HSPCs were treated with buthionine sulfoximine (BSO),an inhibitor of glutathione synthetase,and N-acetyl-L-cysteine (NAC). We investigated the metabolomic landscape of human HSPCs from the fetal,perinatal,and adult developmental stages by in-depth quantitative proteomics and predicted a metabolic switch from the oxidative state to the glycolytic state during human HSPC development. Seahorse assays,mitochondrial activity,ROS level,glucose uptake,and protein synthesis rate analysis supported our findings. In addition,immune-related pathways and antigen presentation were upregulated in UCB or aBM HSPCs,indicating their functional maturation upon development. Glutathione-related metabolic perturbations resulted in distinct responses in human HSPCs and progenitors. Furthermore,the molecular and immunophenotypic differences between human HSPCs at different developmental stages were revealed at the protein level for the first time. The metabolic landscape of human HSPCs at three developmental stages (FL,UCB,and aBM),combined with proteomics and functional validations,substantially extends our understanding of HSC metabolic regulation. These findings provide valuable resources for understanding human HSC function and development during fetal and adult life. The online version contains supplementary material available at 10.1186/s13287-024-03930-x. View Publication

BACKGROUND: The presence of chromosomal abnormalities could have a negative impact for human embryonic stem cell (hESC) applications both in regenerative medicine and in research. A biomarker that allows the identification of chromosomal abnormalities induced in hESC in culture before they take over the culture would represent an important tool for defining optimal culture conditions for hESC. Here we investigate the expression of CD30,reported to be a biomarker of hESCs with abnormal karyotype,in undifferentiated and spontaneously differentiated hESC.backslashnbackslashnMETHODS AND RESULTS: hESC were derived and cultured on mouse fibroblasts in KO-SR containing medium (serum free media) and passaged mechanically. Our results based on analysis at mRNA (RT-PCR) and protein (fluorescence-activated cell sorting and immunocytochemistry) level show that CD30 is expressed in undifferentiated hESC,even at very early passages,without any correlation with the presence of chromosomal anomalies. We also show that the expression of CD30 is rapidly lost during early spontaneous differentiation of hESC.backslashnbackslashnCONCLUSION: We conclude that CD30 expression in hESC cultures is probably a consequence of culture conditions,and that KO-SR may play a role. In addition,the expression of so-called 'stemness' markers does not change in undifferentiated hESC during long-term culture or when cells acquire chromosomal abnormalities. View Publication

Understanding how hematopoietic stem cells (HSCs) are generated and the signals that control this process is a crucial issue for regenerative medicine applications that require in vitro production of HSC. HSCs emerge during embryonic life from an endothelial-like cell population that resides in the aorta-gonad-mesonephros (AGM) region. We show here that β-catenin is nuclear and active in few endothelial nonhematopoietic cells closely associated with the emerging hematopoietic clusters of the embryonic aorta during mouse development. Importantly,Wnt/β-catenin activity is transiently required in the AGM to generate long-term HSCs and to produce hematopoietic cells in vitro from AGM endothelial precursors. Genetic deletion of β-catenin from the embryonic endothelium stage (using VE-cadherin-Cre recombinase),but not from embryonic hematopoietic cells (using Vav1-Cre),precludes progression of mutant cells toward the hematopoietic lineage; however,these mutant cells still contribute to the adult endothelium. Together,those findings indicate that Wnt/β-catenin activity is needed for the emergence but not the maintenance of HSCs in mouse embryos. View Publication

Recent evidence suggests that protease release by neutrophils in the bone marrow may contribute to hematopoietic progenitor cell (HPC) mobilization. Matrix metalloproteinase-9 (MMP-9),neutrophil elastase (NE),and cathepsin G (CG) accumulate in the bone marrow during granulocyte colony-stimulating factor (G-CSF) treatment,where they are thought to degrade key substrates including vascular cell adhesion molecule-1 (VCAM-1) and CXCL12. To test this hypothesis,HPC mobilization was characterized in transgenic mice deficient in one or more hematopoietic proteases. Surprisingly,HPC mobilization by G-CSF was normal in MMP-9-deficient mice,NE x CG-deficient mice,or mice lacking dipeptidyl peptidase I,an enzyme required for the functional activation of many hematopoietic serine proteases. Moreover,combined inhibition of neutrophil serine proteases and metalloproteinases had no significant effect on HPC mobilization. VCAM-1 expression on bone marrow stromal cells decreased during G-CSF treatment of wild-type mice but not NE x CG-deficient mice,indicating that VCAM-1 cleavage is not required for efficient HPC mobilization. G-CSF induced a significant decrease in CXCL12 alpha protein expression in the bone marrow of Ne x CG-deficient mice,indicating that these proteases are not required to down-regulate CXCL12 expression. Collectively,these data suggest a complex model in which both protease-dependent and -independent pathways may contribute to HPC mobilization. View Publication

SummaryStudying the cis-regulatory elements (CREs) of genes in Th17 cells during autoimmune disease progression,such as experimental autoimmune encephalomyelitis (EAE),is often limited by the availability of gene-edited mice. Here,we present a protocol for CRISPR-mediated deletion of a CRE in murine Th17 cells for in vivo assessment of effector function in EAE. We describe steps for dual U6gRNA construction,preparation of retroviruses,viral delivery,and Th17 differentiation. We then detail procedures for in vivo functionality analysis.For complete details on the use and execution of this protocol,please refer to Zhong et al.1,2 Graphical abstract Highlights•Steps for designing and cloning dual U6gRNA cassettes to delete a specific CRE•Instructions for optimized retrovirus production and transduction into CD4+ T cells•Guidance on Th17 differentiation and confirmation of CRE deletion in cultured T cells•Procedures for adoptive transfer of CRISPR-edited Th17 cells to assess in vivo function Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics. Studying the cis-regulatory elements (CREs) of genes in Th17 cells during autoimmune disease progression,such as experimental autoimmune encephalomyelitis (EAE),is often limited by the availability of gene-edited mice. Here,we present a protocol for CRISPR-mediated deletion of a CRE in murine Th17 cells for in vivo assessment of effector function in EAE. We describe steps for dual U6gRNA construction,preparation of retroviruses,viral delivery,and Th17 differentiation. We then detail procedures for in vivo functionality analysis. View Publication

Cytotoxic chemotherapies could cause the dysregulation of hematopoiesis and even put patients at increased risk of hematopoietic malignancy. Therapy-related leukemia is mainly caused by cytotoxic chemotherapy-induced genetic mutations in hematopoietic stem/progenitor cells (HSPCs). In addition to the intrinsic mechanism,some extrinsic events occurring in the bone marrow (BM) microenvironment are also possible mechanisms involved in genetic alteration. In the present study,we investigated the damage to BM stromal cells induced by a chemotherapy drug,daunorubicin (DNR) and further identified the DNA damage in hematopoietic cells caused by drug-treated stromal cells. It was found that treatment with DNR in mice caused a temporary reduction in cell number in each BM stromal cell subpopulation and the impairment of clonal growth potential in BM stromal cells. DNR treatment led to a tendency of senescence,generation of intracellular reactive oxygen species,production of cytokines and chemokines,and dysfunction of mitochondrial in stromal cells. Transcriptome microarray data and gene ontology (GO) or gene set enrichment analysis (GSEA) showed that differentially expressed genes that were down-regulated in response to DNR treatment were significantly enriched in mitochondrion function,and negative regulators of reactive oxygen species. Surprisingly,it was found that DNR-treated stromal cells secreted high levels of H2O2 into the culture supernatant. Furthermore,coculture of hematopoietic cells with DNR-treated stromal cells led to the accumulation of DNA damage as determined by the levels of histone H2AX phosphorylation and 8-oxo-2'-deoxyguanosine in hematopoietic cells. Overall,our results suggest that DNR-induced BM stromal cell damage can lead to genomic instability in hematopoietic cells. View Publication

High-titer,HIV-1-based lentiviral vector particles were found to transduce cytokine-mobilized rhesus macaque CD34(+) cells and clonogenic progenitors very poorly (textless 1%),reflecting the postentry restriction in rhesus cells to HIV infection. To overcome this barrier,we developed a simian immunodeficiency virus (SIV)-based vector system. A single exposure to a low concentration of amphotropic pseudotyped SIV vector particles encoding the green fluorescent protein (GFP) resulted in gene transfer into 68% +/- 1% of rhesus bulk CD34(+) cells and 75% +/- 1% of clonogenic progenitors. Polymerase chain reaction (PCR) analysis of DNA from individual hematopoietic colonies confirmed these relative transduction efficiencies. To evaluate SIV vector-mediated stem cell gene transfer in vivo,3 rhesus macaques underwent transplantation with transduced,autologous cytokine-mobilized peripheral blood CD34(+) cells following myeloablative conditioning. Hematopoietic reconstitution was rapid,and an average of 18% +/- 8% and 15% +/- 7% GFP-positive granulocytes and monocytes,respectively,were observed 4 to 6 months after transplantation,consistent with the average vector copy number of 0.19 +/- 0.05 in peripheral blood leukocytes as determined by real-time PCR. Vector insertion site analysis demonstrated polyclonal reconstitution with vector-containing cells. SIV vectors appear promising for evaluating gene therapy approaches in nonhuman primate models. View Publication

p18 INK4 C (CDKN2C,encoded by p18 INK4c or Cdkn2c ) is an early G1-phase cyclin-dependent kinase inhibitor protein. Previous studies demonstrated enhanced self-renewal capacity of hematopoietic stem cells (HSCs) in p18 −/− mice compared to wild-type (WT) mice. Given the critical role of bone marrow niche cells-particularly mesenchymal stromal cells (MSCs)-in hematopoiesis,this study investigated the functional alterations of p18 −/− MSCs and their impact on hematopoietic support. Bone marrow derived MSCs were isolated from p18 −/− and WT mice. Their proliferation and differentiation capacities were assessed,followed by evaluation of hematopoietic support using cobblestone area-forming cell assay and long-term culture-initiating cell assay. RNA sequencing was performed to analyze the transcriptional profile of p18 −/− MSCs,with a focus on differentially expressed genes (DEGs). Key pathways associated with hematopoietic support were identified using Ingenuity Pathway Analysis. A candidate protein was quantified by ELISA,and its functional role in hematopoietic support was validated via a modified coculture system. p18 −/− MSCs displayed an increased proliferation rate,preferential differentiation toward osteogenesis over adipogenesis,and enhanced hematopoietic support. RNA sequencing analysis identified 137 DEGs,with secreted phosphoprotein 1 ( Spp1,encoding osteopontin,Opn) being significantly upregulated in p18 −/− MSCs. Elevated Opn levels were confirmed in both bone marrow and MSC-conditioned media from p18 −/− mice. Functional validation further demonstrated that Opn enhanced the hematopoietic supportive capacity of MSCs in vitro. p18 deficiency promotes osteogenic differentiation and enhances the hematopoietic supportive function of MSCs,likely mediated by Opn upregulation. These findings suggest a potential therapeutic strategy for improving bone regeneration and HSC expansion. The online version contains supplementary material available at 10.1186/s13287-025-04402-6. View Publication