Multiplexed bioimaging systems have triggered the development of effective assays, contributing new biological information. Although electrochemical imaging is beneficial for quantitative analysis in ...real time, monitoring multiple cell functions is difficult. We have developed a novel electrochemical imaging system, herein, using a large-scale integration (LSI)-based amperometric device for detecting multiple biomolecules simultaneously. This system is designated as an electrochemicolor imaging system in which the current signals from two different types of biomolecules are depicted as a multicolor electrochemical image. The mode-selectable function of the 400-electrode device enables the imaging system and two different potentials can be independently applied to the selected electrodes. The imaging system is successfully applied for detecting multiple cell functions of the embryonic stem (ES) cell and the rat pheochromocytoma (PC12) cell aggregates. To the best of our knowledge, this is the first time that a real-time electrochemical mapping technique for multiple electroactive species, simultaneously, has been reported. The imaging system is a promising bioanalytical method for exploring complex biological phenomena.
•We generated CDA patient-derived iPSCs carrying the KLF1 E325K mutation (CDA-iPSCs).•We developed an inducible expression system of KLF1 E325K using CDA-iPSCs.•We found that KLF1 E325K induced G1 ...cell cycle arrest at the CD71+/CD235a+ stage.
Krüppel-like factor 1 (KLF1), a transcription factor controlling definitive erythropoiesis, is involved in sequential control of terminal cell division and enucleation via fine regulation of key cell cycle regulator gene expression in erythroid lineage cells. Type IV congenital dyserythropoietic anemia (CDA) is caused by a monoallelic mutation at the second zinc finger of KLF1 (c.973G>A, p.E325K). We recently diagnosed a female patient with type IV CDA with the identical missense mutation. To understand the mechanism underlying the dyserythropoiesis caused by the mutation, we generated induced pluripotent stem cells (iPSCs) from the CDA patient (CDA-iPSCs). The erythroid cells that differentiated from CDA-iPSCs (CDA-erythroid cells) displayed multinucleated morphology, absence of CD44, and dysregulation of the KLF1 target gene expression. In addition, uptake of bromodeoxyuridine by CDA-erythroid cells was significantly decreased at the CD235a+/CD71+ stage, and microarray analysis revealed that cell cycle regulator genes were dysregulated, with increased expression of negative regulators such as CDKN2C and CDKN2A. Furthermore, inducible expression of the KLF1 E325K, but not the wild-type KLF1, caused a cell cycle arrest at the G1 phase in CDA-erythroid cells. Microarray analysis of CDA-erythroid cells and real-time polymerase chain reaction analysis of the KLF1 E325K inducible expression system also revealed altered expression of several KLF1 target genes including erythrocyte membrane protein band 4.1 (EPB41), EPB42, glutathione disulfide reductase (GSR), glucose phosphate isomerase (GPI), and ATPase phospholipid transporting 8A1 (ATP8A1). Our data indicate that the E325K mutation in KLF1 is associated with disruption of transcriptional control of cell cycle regulators in association with erythroid membrane or enzyme abnormalities, leading to dyserythropoiesis.
Induced pluripotent stem cells (iPSCs) can be generated from patients with specific diseases by the transduction of reprogramming factors and can be useful as a cell source for cell transplantation ...therapy for various diseases with impaired organs. However, the low efficiency of iPSC derived from somatic cells (0.01–0.1%) is one of the major problems in the field. The phosphoinositide 3-kinase (PI3K) pathway is thought to be important for self-renewal, proliferation, and maintenance of embryonic stem cells (ESCs), but the contribution of this pathway or its well-known negative regulator, phosphatase, and tensin homolog deleted on chromosome ten (Pten), to somatic cell reprogramming remains largely unknown. Here, we show that activation of the PI3K pathway by the Pten inhibitor, dipotassium bisperoxo(5-hydroxypyridine-2-carboxyl)oxovanadate, improves the efficiency of germline-competent iPSC derivation from mouse somatic cells. This simple method provides a new approach for efficient generation of iPSCs.
•Resonance ionization of 93Nb in gas-jet was demonstrated using Ti:Sapphire laser.•The line width of the spectrum in the gas-jet was similar to that in vacuum.•An experimental setup for ...high-resolution RIS was designed.
High-resolution resonance ionization spectroscopy (RIS) is required for laser spectroscopy and trace analysis of short-lived and long-lived radioactive nuclei. We have proposed high-resolution resonance ionization spectroscopy in a gas jet combined with a narrow band-width injection-locked Ti:Sapphire laser. Resonance ionization of stable 93Nb in a gas jet was demonstrated using a broad bandwidth Ti:Sapphire laser. In addition, a setup for high-resolution RIS in a gas-jet was designed using numerical simulations of the gas-jet conditions based on computational fluid dynamics.
Vaccination with irradiated granulocyte macrophage colony-stimulating factor (GM-CSF)-transduced autologous tumor cells (GVAX) has been shown to induce therapeutic antitumor immunity. However, its ...effectiveness is limited. We therefore attempted to improve the antitumor effect by identifying little-known key pathways in GM-CSF-sensitized dendritic cells (GM-DC) in tumor-draining lymph nodes (TDLN). We initially confirmed that syngeneic mice subcutaneously injected with poorly immunogenic Lewis lung carcinoma (LLC) cells transduced with Sendai virus encoding GM-CSF (LLC/SeV/GM) remarkably rejected the tumor growth. Using cDNA microarrays, we found that expression levels of type I interferon (IFN)-related genes, predominantly expressed in plasmacytoid DCs (pDC), were significantly upregulated in TDLN-derived GM-DCs and focused on pDCs. Indeed, mouse experiments demonstrated that the effective induction of GM-CSF-induced antitumor immunity observed in immunocompetent mice treated with LLC/SeV/GM cells was significantly attenuated when pDC-depleted or IFNα receptor knockout (IFNAR(-/-)) mice were used. Importantly, in both LLC and CT26 colon cancer-bearing mice, the combinational use of imiquimod with autologous GVAX therapy overcame the refractoriness to GVAX monotherapy accompanied by tolerability. Mechanistically, mice treated with the combined vaccination displayed increased expression levels of CD86, CD9, and Siglec-H, which correlate with an antitumor phenotype, in pDCs, but decreased the ratio of CD4(+)CD25(+)FoxP3(+) regulatory T cells in TDLNs. Collectively, these findings indicate that the additional use of imiquimod to activate pDCs with type I IFN production, as a positive regulator of T-cell priming, could enhance the immunologic antitumor effects of GVAX therapy, shedding promising light on the understanding and treatment of GM-CSF-based cancer immunotherapy.
Although oncolytic virotherapy is a promising anticancer therapy, antitumor efficacy is hampered by low tumor selectivity. To identify a potent and selective oncolytic virotherapy, we carried out ...large-scale two-step screening of 28 enteroviral strains and found that coxsackievirus B3 (CVB3) possessed specific oncolytic activity against nine human non-small cell lung cancer (NSCLC) cell lines. CVB3-mediated cytotoxicity was positively correlated with the expression of the viral receptors, coxsackievirus and adenovirus receptor, and decay-accelerating factor, on NSCLC cells. In vitro assays revealed that the CVB3 induced apoptosis and phosphoinositide 3-kinase/Akt and mitogen-activated protein (MAP)/extracellular signal-regulated (ERK) kinase (MEK) survival signaling pathways, leading to cytotoxicity and regulation of CVB3 replication. Intratumoral injections of CVB3 elicited remarkable regression of preestablished NSCLC tumors in vivo. Furthermore, administrations of CVB3 into xenografts on the right flank resulted in significantly durable regression of uninjected xenografts on the left flank, where replication-competent CVB3 was detected. All treatments with CVB3 were well tolerated without treatment-related deaths. In addition, after CVB3 infection, NSCLC cells expressed abundant cell surface calreticulin and secreted ATP as well as translocated extranuclear high-mobility group box 1, which are required for immunogenic cell death. Moreover, intratumoral CVB3 administration markedly recruited natural killer cells and granulocytes, both of which contributed to the antitumor effects as shown by depletion assays, macrophages, and mature dendritic cells into tumor tissues. Together, our findings suggest that CVB3 is a potent and well-tolerated oncolytic agent with immunostimulatory properties active against both localized and metastatic NSCLC.
93
Nb(n, n′)
93m
Nb reaction allows retrospective estimation of integrated fast neutron dose in nuclear reactor. We proposed isomer-selective trace analysis of
93m
Nb by Resonance Ionization Mass ...Spectrometry (RIMS) combined with a gas-jet atomic source and an injection locked Ti:Sapphire laser system operated at several kHz. Resonant ionization spectroscopy of Nb in gas-jet using Ti:Sapphire laser was demonstrated.
The congenital dyserythropoietic anemias (CDAs) are congenital red blood cell disorders representing ineffective erythropoiesis and dyserythropoietic changes in the bone marrow. We diagnosed a female ...patient with undiagnosed congenital anemia as type IV CDA caused by a heterozygous missense mutation of the erythroid-specific transcription factor, KLF1; c.973G>A, p. E325K. Although the mutation has been reported in a male patient characterized as hydrops fetalis, severe neonatal jaundice and transfusion-dependent anemia (Arnaud L et al., Am J Hum Genet, 2010), the proband showed relatively mild phenotype showing moderate dyserythropoietic anemia. In order to investigate the pathological significance of mutant KLF1 during erythropoiesis, we generated induced pluripotent stem cells (iPSCs) from peripheral blood of the CDA patient (CDA-iPSCs), and utilized these cells for better understanding of its molecular basis.
Hematopoietic precursors were induced from CDA-iPSCs by embryoid bodies formation. CD34(+) precursor cells were then isolated and cultured in the presence of cytokine cocktail for additional 1-3 weeks (Figure 1). Morphological analysis revealed that many erythroblastic cells derived from CDA-iPSCs were multinucleated, in accordance with that of bone marrow erythroblasts from CDA patient. Flow cytometric analysis showed that CDA-iPSC-derived cells contained significantly lower percentage of CD235a(+)/CD71(+) erythroid lineage cells than the cells derived from control iPSCs. CD71 expression decreased in time during erythroid differentiation culture in control CD235a(+) cells, whereas it maintained in CDA-iPSC-derived cells, indicating inappropriate maturation of erythroblastic cells.
These data promoted us to explore the possibility of cell death in CDA-iPSC-derived cells during erythroid differentiation culture by comprehensive microarray analysis of erythroblastic cells. In CDA-iPSC-derived cells, many positive and negative regulators of cell-cycle, such as E2F2 and CDKN2C, were differentially expressed, indicating the disruption of cell-cycle control during late stage of erythropoiesis from CDA-iPSCs. In consistent with this, significantly lower percentage of BrdU-uptaking cells were detected in CD235a(+) cells derived from CDA-iPSCs after 3 hour pulse of BrdU during erythroid liquid culture.
Most of the KLF1 mutations with functional alterations currently reported are classified into hypomorphic variants or truncating loss-of-function variants. KLF1 E325K has been reported to actively interfere with transcription of KLF1 target genes (Arnaud et al., 2010). Our findings suggest that KLF1 E325K variant might act to disrupt the transcriptional control of various cell cycle regulators including known KLF1 target genes E2F2 and CDKN2C, which lead to the pathological cell-cycle arrest in type IV CDA patients. Our model provides insights on understanding the mechanisms of type IV CDA, and it would be a useful tool for drug screening and identification of novel biomarkers.
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Kohara:neo ALA CO.,LTD.: Research Funding. Sugawara:neo ALA CO.,LTD.: Research Funding. Yoshie:neo ALA CO.,LTD.: Research Funding. Tani:neo ALA CO.,LTD.: Research Funding; SHINNIHON PHARMACEUTICAL CO., LTD: Research Funding.
The congenital dyserythropoietic anemias (CDAs) are inherited red blood cell disorders representing ineffective erythropoiesis and dyserythropoietic changes in the bone marrow. We recently diagnosed ...a female patient with undiagnosed congenital anemia as type IV CDA caused by a heterozygous missense mutation of the erythroid-specific transcription factor, KLF1; c.973G>A, p. E325K. Although the mutation has been reported in a male patient characterized as hydrops fetalis, severe neonatal jaundice and transfusion-dependent anemia (Arnaud L et al., Am J Hum Genet, 2010), the proband showed relatively mild phenotype showing moderate dyserythropoietic anemia. In order to investigate the pathological significance of mutant KLF1 during erythroid cell development and differentiation, we generated induced pluripotent stem cells (iPSCs) from peripheral blood of the CDA patient (CDA-iPSCs), and utilized these cells to establish in vitro CDA model for better understanding of its molecular basis. CDA-iPSCs were generated from T lymphocytes in peripheral blood mononuclear cells. Hematopoietic precursors were induced from CDA-iPSCs by embryoid bodies formation. CD34(+) precursor cells were isolated and further cultured in liquid culture with cytokine cocktail (erythropoietin (EPO), interleukin (IL)-3, and stem cell factor (SCF)) for additional 1-3 weeks. Flow cytometric analysis showed that CDA-iPSC-derived cells contained significantly lower percentage of CD235a(+)/CD71(+) erythroid lineage cells than the cells derived from control iPSCs, and lack expression of the adhesion molecule CD44, which is known to be down regulated in peripheral blood erythroid cells of CDA patients (Arnaud L et al., Am J Hum Genet, 2010). In addition, colony-forming unit (CFU) assay indicated that CD34(+) fraction derived from CDA-iPSCs contained a lower number of erythroid colony-forming cells and the most of the cells in these colonies are morphologically abnormal, in comparison with control iPSCs. We next evaluated mRNA expression levels of fetal (HBG1 and HBG2), embryonic (HBE), and adult (HBB) globins, resulting that HBG1 and HBG2 were significantly increased in CDA-iPSCs-derived erythroid lineage cells, whereas HBE showed no significant change and HBB was decreased in CDA-iPSCs-derived erythroid lineage cells. However, BCL11A, one of the target genes of KLF1 and also known as a suppressor of HBG1 and HBG2, was not decreased in the presence KLF1 gene mutation, indicating that elevated HBG1 and HBG2 in CDA-iPSCs-derived erythroid cells was mediated by other mechanism like Leukemia/lymphoma Related Factor (LRF; Masuda T et al., Science, 2016). Here we suggest that our model provides insights on understanding the mechanisms of type IV CDA and the effect of KLF1 gene mutation on clinical phenotype and it would be a useful tool for drug screening and identification of novel biomarker for the rare congenital anemia.
Figure 1 Induction of erythroid differentiation from human iPSCs
Figure 2 Flow cytometric analysis of erythroid cells induced from CDA-iPSCs
Figure 3 RT-PCR analysis of erythroid cells induced from CDA-iPSCs
Kohara:SBI Pharmaceuticals: Research Funding. Miyamoto:SBI Pharmaceuticals: Research Funding. Tani:Oncolys BioPharma: Equity Ownership; SymBio Pharmaceuticals: Consultancy, Equity Ownership; SBI Pharmaceuticals: Research Funding; Shinnihonseiyaku: Research Funding.
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