N
-methyladenosine (m
A) is an abundant nucleotide modification in mRNA that is required for the differentiation of mouse embryonic stem cells. However, it remains unknown whether the m
A ...modification controls the differentiation of normal and/or malignant myeloid hematopoietic cells. Here we show that shRNA-mediated depletion of the m
A-forming enzyme METTL3 in human hematopoietic stem/progenitor cells (HSPCs) promotes cell differentiation, coupled with reduced cell proliferation. Conversely, overexpression of wild-type METTL3, but not of a catalytically inactive form of METTL3, inhibits cell differentiation and increases cell growth. METTL3 mRNA and protein are expressed more abundantly in acute myeloid leukemia (AML) cells than in healthy HSPCs or other types of tumor cells. Furthermore, METTL3 depletion in human myeloid leukemia cell lines induces cell differentiation and apoptosis and delays leukemia progression in recipient mice in vivo. Single-nucleotide-resolution mapping of m
A coupled with ribosome profiling reveals that m
A promotes the translation of c-MYC, BCL2 and PTEN mRNAs in the human acute myeloid leukemia MOLM-13 cell line. Moreover, loss of METTL3 leads to increased levels of phosphorylated AKT, which contributes to the differentiation-promoting effects of METTL3 depletion. Overall, these results provide a rationale for the therapeutic targeting of METTL3 in myeloid leukemia.
The cytokine IL-12 induces IFN-γ production by T and NK cells. In preclinical models, it contributes to antitumor immunity. However, in clinical testing, it has shown limited benefit in patients with ...any one of a variety of malignancies. Moreover, in a clinical trial testing a combination of IL-12 and rituximab in patients with follicular B cell non-Hodgkin lymphoma (FL), those treated with IL-12 showed a lower response rate, suggesting that IL-12 actually plays a detrimental role. Here, we investigated whether the failure of IL-12 treatment for FL was due to T cell exhaustion, a condition characterized by reduced T cell differentiation, proliferation, and function, which has been observed in chronic viral infection. We found that extended exposure to IL-12 induced T cell exhaustion and contributed to the poor prognosis in FL patients. Long-term exposure of freshly isolated human CD4+ T cells to IL-12 in vitro caused T cell dysfunction and induced expression of TIM-3, a T cell immunoglobulin and mucin domain protein with a known role in T cell exhaustion, via an IFN-γ-independent mechanism. TIM-3 was required for the negative effect of IL-12 on T cell function. Importantly, TIM-3 also was highly expressed on intratumoral T cells that displayed marked functional impairment. Our findings identify IL-12- and TIM-3-mediated exhaustion of T cells as a mechanism for poor clinical outcome when IL-12 is administered to FL patients.
The development of nanomaterials for biomedical and biotechnological applications is an area of research that holds great promise and intense interest, and carbon-based nanostructures in particular, ...such as carbon nanotubes (CNTs), are attracting an increasing level of attention. One of the key advantages that CNTs offer is the possibility of effectively crossing biological barriers, which would allow their use in the delivery of therapeutically active molecules. Our laboratories have been investigating the use of CNTs in biomedical applications, and in particular as nanovectors for therapeutic agent delivery. The interaction between cells and CNTs is a critical issue that will determine any future biological application of such structures. Here we show that various types of functionalized carbon nanotubes (f-CNTs) exhibit a capacity to be taken up by a wide range of cells and can intracellularly traffic through different cellular barriers.
After antigen encounter by CD4+ T cells, polarizing cytokines induce the expression of master regulators that control differentiation. Inactivation of the histone methyltransferase Ezh2 was found to ...specifically enhance T helper 1 (Th1) and Th2 cell differentiation and plasticity. Ezh2 directly bound and facilitated correct expression of Tbx21 and Gata3 in differentiating Th1 and Th2 cells, accompanied by substantial trimethylation at lysine 27 of histone 3 (H3K27me3). In addition, Ezh2 deficiency resulted in spontaneous generation of discrete IFN-γ and Th2 cytokine-producing populations in nonpolarizing cultures, and under these conditions IFN-γ expression was largely dependent on enhanced expression of the transcription factor Eomesodermin. In vivo, loss of Ezh2 caused increased pathology in a model of allergic asthma and resulted in progressive accumulation of memory phenotype Th2 cells. This study establishes a functional link between Ezh2 and transcriptional regulation of lineage-specifying genes in terminally differentiated CD4+ T cells.
•Ezh2 specifically constrains differentiation and plasticity of Th1 and Th2 cells•Ezh2 controls correct expression of Tbx21 and Gata3 in developing Th1 and Th2 cells•Ezh2 inhibits spontaneous generation of IFN-γ-producing cells via repression of Eomes•Ezh2 constrains asthma pathology and memory phenotype Th2 cell accumulation in vivo
Abstract Boronic acid-rich chitosan-poly( N -3-acrylamidophenylboronic acid) nanoparticles (CS-PAPBA NPs) with the tunable size were successfully prepared by polymerizing N -3-acrylamidophenylboronic ...acid in the presence of chitosan in an aqueous solution. The CS-PAPBA NPs were then functionalized by a tumor-penetrating peptide iRGD and loading doxorubicin (DOX). The interaction between boronic acid groups of hydrophobic PAPBA and the amino groups of hydrophilic chitosan inside the nanoparticles was examined by solid-state NMR measurement. The size and morphology of nanoparticles were characterized by dynamic light scattering and electron microscopy. The cellular uptake, tumor penetration, biodistribution and antitumor activity of the nanoparticles were evaluated by using three-dimensional (3-D) multicellular spheroids (MCs) as the in vitro model and H22 tumor-bearing mice as the in vivo model. It was found that the iRGD-conjugated nanoparticles significantly improved the efficiency of DOX penetration in MCs, compared with free DOX and non-conjugated nanoparticles, resulting in the efficient cell killing in the MCs. In vivo antitumor activity examination indicated that iRGD-conjugated CS-PAPBA nanoparticles promoted the accumulation of nanoparticles in tumor tissue and enhanced their penetration in tumor areas, both of which improved the efficiency of DOX-loaded nanoparticles in restraining tumor growth and prolonging the life time of H22 tumor-bearing mice.
In humans, the endometrium, the uterine mucosal lining, undergoes dynamic changes throughout the menstrual cycle and pregnancy. Despite the importance of the endometrium as the site of implantation ...and nutritional support for the conceptus, there are no long-term culture systems that recapitulate endometrial function in vitro. We adapted conditions used to establish human adult stem-cell-derived organoid cultures to generate three-dimensional cultures of normal and decidualized human endometrium. These organoids expand long-term, are genetically stable and differentiate following treatment with reproductive hormones. Single cells from both endometrium and decidua can generate a fully functional organoid. Transcript analysis confirmed great similarity between organoids and the primary tissue of origin. On exposure to pregnancy signals, endometrial organoids develop characteristics of early pregnancy. We also derived organoids from malignant endometrium, and so provide a foundation to study common diseases, such as endometriosis and endometrial cancer, as well as the physiology of early gestation.
Cancer is one of the main causes of death around the world, lacking efficient clinical treatments that generally present severe side effects. In recent years, various nanosystems have been explored ...to specifically target tumor tissues, enhancing the efficacy of cancer treatment and minimizing the side effects. In particular, bladder cancer is the ninth most common cancer worldwide and presents a high survival rate but serious recurrence levels, demanding an improvement in the existent therapies. Here, we present urease-powered nanomotors based on mesoporous silica nanoparticles that contain both polyethylene glycol and anti-FGFR3 antibody on their outer surface to target bladder cancer cells in the form of 3D spheroids. The autonomous motion is promoted by urea, which acts as fuel and is inherently present at high concentrations in the bladder. Antibody-modified nanomotors were able to swim in both simulated and real urine, showing a substrate-dependent enhanced diffusion. The internalization efficiency of the antibody-modified nanomotors into the spheroids in the presence of urea was significantly higher compared with antibody-modified passive particles or bare nanomotors. Furthermore, targeted nanomotors resulted in a higher suppression of spheroid proliferation compared with bare nanomotors, which could arise from the local ammonia production and the therapeutic effect of anti-FGFR3. These results hold significant potential for the development of improved targeted cancer therapy and diagnostics using biocompatible nanomotors.
Summary The liver has the unique capacity to regenerate in response to a damaging event. Liver regeneration is hereby largely driven by hepatocyte proliferation, which in turn relies on cell cycling. ...The hepatocyte cell cycle is a complex process that is tightly regulated by several well-established mechanisms. In vitro , isolated hepatocytes do not longer retain this proliferative capacity. However, in vitro cell growth can be boosted by immortalization of hepatocytes. Well-defined immortalization genes can be artificially overexpressed in hepatocytes or the cells can be conditionally immortalized leading to controlled cell proliferation. This paper discusses the current immortalization techniques and provides a state-of-the-art overview of the actually available immortalized hepatocyte-derived cell lines and their applications.
Introduction
The purpose of the present investigation is to report on detailed complications among a much larger group of 2372 orthopaedic patients treated with stem cell injections who were followed ...in a treatment registry for up to nine years.
Methods
All patients underwent an MSC-based, percutaneous injection treatment of an orthopaedic condition between December 2005 and September 2014 at one of 18 clinical facilities. Treated areas of the body included the knee, hip, ankle/foot, hand/wrist, elbow, shoulder, and spine. The patients were followed prospectively via enrollment in a treatment registry. Patients were followed prospectively at one, three, six and 12 months, and annually thereafter, using an electronic system, ClinCapture software.
Results
A total of 3012 procedures were performed on 2372 patients with follow-up period of 2.2 years. A total of 325 adverse events were reported. The majority were pain post-procedure (n = 93, 3.9 % of the study population) and pain due to progressive degenerative joint disease (n = 90, 3.8 % of the study population). Seven cases reported neoplasms, a lower rate than in the general population. The lowest rate of adverse events was observed among patients injected with BMC alone.
Conclusion
Lowest rate of adverse events was among those patients receiving BMC injections alone, but the higher rate of AEs for BMC plus adipose and cultured cells was readily explained by the nature of the therapy or the longer follow-up. There was no clinical evidence to suggest that treatment with MSCs of any type in this study increased the risk of neoplasm.
Collective cell migration is a hallmark of wound repair, cancer invasion and metastasis, immune responses, angiogenesis, and embryonic morphogenesis. Wound healing is a complex cellular and ...biochemical process necessary to restore structurally damaged tissue. It involves dynamic interactions and crosstalk between various cell types, interaction with extracellular matrix molecules, and regulated production of soluble mediators and cytokines. In cutaneous wound healing, skin cells migrate from the wound edges into the wound to restore skin integrity. Analysis of cell migration in vitro is a useful assay to quantify alterations in cell migratory capacity in response to experimental manipulations. Although several methods exist to study cell migration (such as Boyden chamber assay, barrier assays, and microfluidics-based assays), in this short report we will explain the wound healing assay, also known as the “in vitro scratch assay” as a simple, versatile, and cost-effective method to study collective cell migration and wound healing.
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