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

BackgroundPhotoreceptor death leads to inherited blinding retinal diseases,such as retinitis pigmentosa (RP). As disease progression often outpaces therapeutic advances,developing effective treatments is urgent. This study evaluates the efficacy of small peptides derived from pigment epithelium-derived factor (PEDF),which are known to restrict common cell death pathways associated with retinal diseases.MethodsWe tested chemically synthesized peptides (17-mer and H105A) with affinity for the PEDF receptor,PEDF-R,delivered as eye drops to two RP mouse models: rd10 (phosphodiesterase 6b mutation) and RhoP23H/+ (rhodopsin P23H mutation). Additionally,we engineered AAV-H105A vectors for intravitreal delivery in RhoP23H/+ mice. To assess peptide effects in human tissue,we used retinal organoids exposed to cigarette smoke extract,a model of oxidative stress. Photoreceptor survival,morphology and function were evaluated.ResultsHere we show that peptides 17-mer and H105A delivered via eye drops successfully reach the retina,promote photoreceptor survival,and improve retinal function in both RP mouse models. Intravitreal delivery of a AAV-H105A vector delays photoreceptor degeneration in RhoP23H/+ mice up to six months. In human retinal organoids,peptide H105A specifically prevents photoreceptor death induced by oxidative stress,a contributing factor to RP progression.ConclusionsPEDF peptide-based eye drops offer a promising,minimally invasive therapy to prevent photoreceptor degeneration in retinal disorders,with a favorable safety profile. Plain language summaryRetinitis pigmentosa (RP) is a rare inherited condition that causes the gradual death of photoreceptors (light-sensing cells) in the eye,leading to vision loss. There is currently no cure. This study tested a potential treatment using small protein fragments (peptides) from PEDF,a protective protein naturally found in the eye. Researchers delivered these peptides through eye drops or gene therapy in mouse models of RP and to human retinal organoids (lab-grown retina tissue). Mice treated early maintained healthy vision cells,while untreated mice experienced rapid cell loss and vision decline. These results suggest that peptide-based eye drops could be a simple,safe,and effective way to slow vision loss in patients with RP. Bernardo-Colón et al. evaluate small peptides derived from the neurotrophic region of pigment epithelium-derived factor (PEDF) as potential therapeutics for retinitis pigmentosa using mouse models and human retinal organoids. A significant delay in photoreceptor death with eye drop or gene therapy delivery is seen. View Publication

Craniosynostosis is a multigenic congenital condition in which one or more calvarial sutures have prematurely fused during the development of the fetus. Pathogenic variants in FGFR2 are associated with the development of syndromic craniosynostosis,such as Crouzon,Apert and Pfeifer syndromes. Investigation of FGFR2 -linked craniosynostosis is hindered by the lack of appropriate in vitro models. Patient-derived human induced pluripotent stem cell (hiPSC) in vitro disease models provide the opportunity to investigate the disease,identify molecular targets for pharmaceutical treatments,and enable the generation of autologous pluripotent stem cell catalogues. Here,we report three patient-derived hiPSC lines carrying the C342Y,S252W or E565G FGFR2 pathogenic variant. The patient hiPSC lines express characteristic pluripotency markers and display distinct phosphorylation profiles under unstimulated conditions. FGFR2 C342Y showed autophosphorylation in the absence of bFGF ligand,although downstream docking proteins PLCγ and FRS2α were not phosphorylated. FGFR2 S252W and FGFR2 E565G hiPSCs showed increased phosphorylation of docking proteins PLCγ and FRS2α,whereas FGFR2 was not phosphorylated. These patient hiPSC lines provide molecular and cellular options to investigate FGFR2 -linked craniosynostosis in the patient-specific genomic context and develop therapeutic modalities. View Publication

Cancer-associated fibroblasts (CAFs) play pivotal roles in solid tumor initiation,growth,and immune evasion. However,the optimal biomimetic modeling conditions remain elusive. In this study,we investigated the effects of 2D and 3D culturing conditions on human primary CAFs integrated into a modular tumor microenvironment (TME). Using single-nucleus RNA sequencing (snRNAseq) and Proteomics’ Proximity Extension Assays,we characterized CAF transcriptomic profiles and cytokine levels. Remarkably,when cultured in 2D,CAFs exhibited a myofibroblast (myCAF) subtype,whereas in 3D tumor spheroid cultures,CAFs displayed a more inflammatory (iCAF) pathological state. By integrating single-cell gene expression data with functional interrogations of critical TME-related processes [natural killer (NK)-mediated tumor killing,monocyte migration,and macrophage differentiation],we were able to reconcile form with function. In 3D TME spheroid models,CAFs enhance cancer cell growth and immunologically shield cells from NK cell-mediated cytotoxicity,in striking contrast with their 2D TME counterparts. Notably,3D CAF-secreted proteins manifest a more immunosuppressive profile by enhancing monocyte transendothelial migration and differentiation into M2-like tumor-associated macrophages (TAMs). Our findings reveal a more immunosuppressive and clinically relevant desmoplastic TME model that can be employed in industrial drug discovery campaigns to expand the cellular target range of chemotherapeutics. View Publication

HIV-1 replication in simian cells is restricted at an early postentry step because of the presence of an inhibitory cellular factor. This block reduces the usefulness of HIV-1-based lentiviral vectors in primate animal models. Here,we demonstrate that substitution of the cyclophilin A (CyPA) binding region in the capsid of an HIV-1-based lentiviral vector (LV) with that of the macrophage tropic HIV-1 Ba-L resulted in a vector that was resistant to the inhibitory effect and efficiently transduced simian cells. Notably,the chimeric gag LV efficiently transduced primary simian hematopoietic progenitor cells,a critical cellular target in gene therapy. The alterations in the CyPA binding region did not affect CyPA incorporation; however,transduction by the gag chimeric LV seemed to be relatively insensitive to cyclosporin A,indicating that it does not require CyPA for early postentry steps. In dual infection experiments,the gag chimeric LV failed to remove the block to transduction of the WT LV,suggesting that the gag chimeric LV did not saturate the inhibitory simian cellular factor. These data suggest that the CyPA binding region of capsid contains a viral determinant involved in the postentry restriction of HIV-1-based lentiviral vectors. Overall,the findings demonstrate that the host range of HIV-1-based LV can be altered by modifications in the packaging construct. View Publication

The future use of adult mesenchymal stem cells (MSCs) for human therapies depends on the establishment of preclinical studies with other mammals such as mouse. Surprisingly,purification and characterisation of murine MSCs were only poorly documented. The aim of this study was to purify mouse MSCs from adult bone marrow and to functionally characterise their abilities to differentiate along diverse lineages. Adherent cells from adult C57Bl/6J mouse bone marrow were depleted of granulo-monocytic cells and subsequently allowed to grow on fibronectin-coated dishes in presence of fetal bovine serum and growth factors. The growing fibroblastoid cell population primarily consisted of spindle- and star-shaped cells with significant renewal capacity as they were cultured until 30 passages (about 60 doubling population). We fully demonstrated the MSC phenotype of these cells by inducing them to differentiate along osteoblastic,adipocytic,and chondrocytic pathways. Mouse MSCs (mMSCs) sharing the same morphological and functional characteristics as human MSCs can be successfully isolated from adult bone marrow without previous mouse or bone marrow treatment. Therefore,mMSCs will be an important tool to study the in vivo behaviour and fate of this cell type after grafting in mouse pathology models. View Publication

In this study,we analyzed IL-2-activated polyclonal natural killer (NK) cells derived from 2 patients affected by leukocyte adhesion deficiency type I (LAD1),an immunodeficiency characterized by mutations of the gene coding for CD18,the beta subunit shared by major leukocyte integrins. We show that LAD1 NK cells express normal levels of various triggering NK receptors (and coreceptors) and that mAb-mediated engagement of these receptors results in the enhancement of both NK cytolytic activity and cytokine production. Moreover,these activating NK receptors were capable of recognizing their specific ligands on target cells. Thus,LAD1 NK cells,similarly to normal NK cells,were capable of killing most human tumor cells analyzed and produced high amounts of IFN-gamma when cocultured in presence of target cells. Murine target cells represented a common exception,as they were poorly susceptible to LAD1 NK cells. Finally,LAD1 NK cells could efficiently kill or induce maturation of monocyte-derived immature dendritic cells (DCs). Altogether our present study indicates that in LAD1 patients,3 important functions of NK cells (eg,cytotoxicity,IFN-gamma production,and DC editing) are only marginally affected and provides new insight on the cooperation between activating receptors and LFA-1 in the induction of NK cell activation and function. View Publication

The identification of self-renewing and multipotent neural stem cells (NSCs) in the mammalian brain holds promise for the treatment of neurological diseases and has yielded new insight into brain cancer. However,the complete repertoire of signaling pathways that governs the proliferation and self-renewal of NSCs,which we refer to as the 'ground state',remains largely uncharacterized. Although the candidate gene approach has uncovered vital pathways in NSC biology,so far only a few highly studied pathways have been investigated. Based on the intimate relationship between NSC self-renewal and neurosphere proliferation,we undertook a chemical genetic screen for inhibitors of neurosphere proliferation in order to probe the operational circuitry of the NSC. The screen recovered small molecules known to affect neurotransmission pathways previously thought to operate primarily in the mature central nervous system; these compounds also had potent inhibitory effects on cultures enriched for brain cancer stem cells. These results suggest that clinically approved neuromodulators may remodel the mature central nervous system and find application in the treatment of brain cancer. View Publication

Pluripotency can be induced in differentiated murine and human cells by retroviral transduction of Oct4,Sox2,Klf4,and c-Myc. We have devised a reprogramming strategy in which these four transcription factors are expressed from doxycycline (dox)-inducible lentiviral vectors. Using these inducible constructs,we derived induced pluripotent stem (iPS) cells from mouse embryonic fibroblasts (MEFs) and found that transgene silencing is a prerequisite for normal cell differentiation. We have analyzed the timing of known pluripotency marker activation during mouse iPS cell derivation and observed that alkaline phosphatase (AP) was activated first,followed by stage-specific embryonic antigen 1 (SSEA1). Expression of Nanog and the endogenous Oct4 gene,marking fully reprogrammed cells,was only observed late in the process. Importantly,the virally transduced cDNAs needed to be expressed for at least 12 days in order to generate iPS cells. Our results are a step toward understanding some of the molecular events governing epigenetic reprogramming. View Publication

Retinoic acid (RA) produced by intestinal dendritic cells (DCs) imprints gut-homing specificity on lymphocytes and enhances Foxp3(+) regulatory T-cell differentiation. The expression of aldehyde dehydrogenase (ALDH) 1A in these DCs is essential for the RA production. However,it remains unclear how the steady-state ALDH1A expression is induced under specific pathogen-free (SPF) conditions. Here,we found that bone marrow-derived dendritic cells (BM-DCs) generated with granulocyte-macrophage colony-stimulating factor (GM-CSF) expressed Aldh1a2,an isoform of Aldh1a,but that fms-related tyrosine kinase 3 ligand-generated BM-DCs did not. DCs from mesenteric lymph nodes (MLN) and Peyer's patches (PP) of normal SPF mice expressed ALDH1A2,but not the other known RA-producing enzymes. Employing a flow cytometric method,we detected ALDH activities in 10-30% of PP-DCs and MLN-DCs. They were CD11c(high)CD4(-/low)CD8alpha(intermediate)CD11b(-/low) F4/80(low/intermediate)CD45RB(low)CD86(high)MHC class II(high)B220(-)CD103(+). Equivalent levels of aldehyde dehydrogenase activity (ALDHact) and ALDH1A2 expression were induced synergistically by GM-CSF and IL-4 in splenic DCs in vitro. In BM-DCs,however,additional signals via Toll-like receptors or RA receptors were required for inducing the equivalent levels. The generated ALDH1A2(+) DCs triggered T cells to express gut-homing receptors or Foxp3. GM-CSF receptor-deficient or vitamin A-deficient mice exhibited marked reductions in the ALDHact in intestinal DCs and the T cell number in the intestinal lamina propria,whereas IL-4 receptor-mediated signals were dispensable. GM-CSF(+)CD11c(-)F4/80(+) cells existed constitutively in the intestinal tissues. The results suggest that GM-CSF and RA itself are pivotal among multiple microenvironment factors that enable intestinal DCs to produce RA. View Publication

The metabolism of oxygen,although central to life,produces reactive oxygen species (ROS) that have been implicated in processes as diverse as cancer,cardiovascular disease and ageing. It has recently been shown that central nervous system stem cells and haematopoietic stem cells and early progenitors contain lower levels of ROS than their more mature progeny,and that these differences are critical for maintaining stem cell function. We proposed that epithelial tissue stem cells and their cancer stem cell (CSC) counterparts may also share this property. Here we show that normal mammary epithelial stem cells contain lower concentrations of ROS than their more mature progeny cells. Notably,subsets of CSCs in some human and murine breast tumours contain lower ROS levels than corresponding non-tumorigenic cells (NTCs). Consistent with ROS being critical mediators of ionizing-radiation-induced cell killing,CSCs in these tumours develop less DNA damage and are preferentially spared after irradiation compared to NTCs. Lower ROS levels in CSCs are associated with increased expression of free radical scavenging systems. Pharmacological depletion of ROS scavengers in CSCs markedly decreases their clonogenicity and results in radiosensitization. These results indicate that,similar to normal tissue stem cells,subsets of CSCs in some tumours contain lower ROS levels and enhanced ROS defences compared to their non-tumorigenic progeny,which may contribute to tumour radioresistance. View Publication

The cancer stem cell hypothesis asserts that malignancies arise in tissue stem and/or progenitor cells through the dysregulation or acquisition of self-renewal. In order to determine whether the dietary polyphenols,curcumin,and piperine are able to modulate the self-renewal of normal and malignant breast stem cells,we examined the effects of these compounds on mammosphere formation,expression of the breast stem cell marker aldehyde dehydrogenase (ALDH),and Wnt signaling. Mammosphere formation assays were performed after curcumin,piperine,and control treatment in unsorted normal breast epithelial cells and normal stem and early progenitor cells,selected by ALDH positivity. Wnt signaling was examined using a Topflash assay. Both curcumin and piperine inhibited mammosphere formation,serial passaging,and percent of ALDH+ cells by 50% at 5 microM and completely at 10 microM concentration in normal and malignant breast cells. There was no effect on cellular differentiation. Wnt signaling was inhibited by both curcumin and piperine by 50% at 5 microM and completely at 10 microM. Curcumin and piperine separately,and in combination,inhibit breast stem cell self-renewal but do not cause toxicity to differentiated cells. These compounds could be potential cancer preventive agents. Mammosphere formation assays may be a quantifiable biomarker to assess cancer preventive agent efficacy and Wnt signaling assessment can be a mechanistic biomarker for use in human clinical trials. View Publication

The question of whether dedicated progenitor cells exist in adult vertebrate pancreas remains controversial. Centroacinar cells and terminal duct (CA/TD) cells lie at the junction between peripheral acinar cells and the adjacent ductal epithelium,and are frequently included among cell types proposed as candidate pancreatic progenitors. However these cells have not previously been isolated in a manner that allows formal assessment of their progenitor capacities. We have found that a subset of adult CA/TD cells are characterized by high levels of ALDH1 enzymatic activity,related to high-level expression of both Aldh1a1 and Aldh1a7. This allows their isolation by FACS using a fluorogenic ALDH1 substrate. FACS-isolated CA/TD cells are relatively depleted of transcripts associated with differentiated pancreatic cell types. In contrast,they are markedly enriched for transcripts encoding Sca1,Sdf1,c-Met,Nestin,and Sox9,markers previously associated with progenitor populations in embryonic pancreas and other tissues. FACS-sorted CA/TD cells are uniquely able to form self-renewing pancreatospheres" in suspension culture� View Publication