Long-term engrafting multilineage hematopoietic cells differentiated from human induced pluripotent stem cells.

Hematopoietic stem cells (HSCs) derived from human induced pluripotent stem cells (iPS cells) have important biomedical applications. We identified differentiation conditions that generate HSCs defined by robust long-term multilineage engraftment in immune-deficient NOD,B6.Prkdc Il2rg Kit mice.

Indirect calorimetry directed feeding and cycling in the older ICU population: a pilot randomised controlled trial.

Background: Older critically ill patients experience rapid muscle loss during stay in an intensive care unit (ICU) due to physiological stress and increased catabolism. This may lead to increased ICU length of stay, delayed weaning from ventilation and persistent functional limitations. We hypothesized that with optimal nutrition and early physical therapy acting in synergism, we can reduce muscle mass loss and improve functional outcomes.

Generation of heterozygous (MCRIi030-A-1) and homozygous (MCRIi030-A-2) NR2F2/COUP-TFII knockout human iPSC lines.

The NR2F2 gene encodes the transcription factor COUP-TFII, which is upregulated in embryonic mesoderm. Heterozygous variants in NR2F2 cause a spectrum of congenital anomalies including cardiac and gonadal phenotypes. We generated heterozygous (MCRIi030-A-1) and homozygous (MCRIi030-A-2) NR2F2-knockout induced pluripotent stem cell (iPSC) lines from human fibroblasts using a one-step protocol for CRISPR/Cas9 gene-editing and episomal-based reprogramming.

Identification of small-molecule binding sites of a ubiquitin-conjugating enzyme-UBE2T through fragment-based screening.

UBE2T is an attractive target for drug development due to its linkage with several types of cancers. However, the druggability of ubiquitin-conjugating E2 (UBE2T) is low because of the lack of a deep and hydrophobic pocket capable of forming strong binding interactions with drug-like small molecules. Here, we performed fragment screening using F-nuclear magnetic resonance (NMR) and validated the hits with H- N-heteronuclear single quantum coherence (HSQC) experiment and X-ray crystallographic studies.

Modeling human skeletal development using human pluripotent stem cells.

Chondrocytes and osteoblasts differentiated from induced pluripotent stem cells (iPSCs) will provide insights into skeletal development and genetic skeletal disorders and will generate cells for regenerative medicine applications. Here, we describe a method that directs iPSC-derived sclerotome to chondroprogenitors in 3D pellet culture then to articular chondrocytes or, alternatively, along the growth plate cartilage pathway to become hypertrophic chondrocytes that can transition to osteoblasts. Osteogenic organoids deposit and mineralize a collagen I extracellular matrix (ECM), mirroring in vivo endochondral bone formation.

Digital treatment planning and clear aligner therapy: A retrospective cohort study.

Objective: To investigate the total number of digital treatment plan (DTPs) and aligners manufactured for clear aligner therapy (CAT) by Invisalign from initial treatment planning to the completion of CAT.

Design: A retrospective cohort study.

Material And Methods: A total of 30 patients, from each of 11 experienced orthodontists, who commenced treatment over a 12-month period, were assessed regarding the number of DTPs and aligners prescribed from initial planning to completion of CAT.

Lymphoid cell development from fetal hematopoietic progenitors and human pluripotent stem cells.

Lymphoid cells encompass the adaptive immune system, including T and B cells and Natural killer T cells (NKT), and innate immune cells (ILCs), including Natural Killer (NK) cells. During adult life, these lineages are thought to derive from the differentiation of long-term hematopoietic stem cells (HSCs) residing in the bone marrow. However, during embryogenesis and fetal development, the ontogeny of lymphoid cells is both complex and multifaceted, with a large body of evidence suggesting that lymphoid lineages arise from progenitor cell populations antedating the emergence of HSCs.

Mimicry of embryonic circulation enhances the hoxa hemogenic niche and human blood development.

Precursors of the adult hematopoietic system arise from the aorta-gonad-mesonephros (AGM) region shortly after the embryonic circulation is established. Here, we develop a microfluidic culture system to mimic the primitive embryonic circulation and address the hypothesis that circulatory flow and shear stress enhance embryonic blood development. Embryonic (HOXA) hematopoiesis was derived from human pluripotent stem cells and induced from mesoderm by small-molecule manipulation of TGF-β and WNT signaling (SB/CHIR).

Human pluripotent stem cell-derived macrophages host Mycobacterium abscessus infection.

Human macrophages are a natural host of many mycobacterium species, including Mycobacterium abscessus (M. abscessus), an emerging pathogen affecting immunocompromised and cystic fibrosis patients with few available treatments. The search for an effective treatment is hindered by the lack of a tractable in vitro intracellular infection model.

Mapping human haematopoietic stem cells from haemogenic endothelium to birth.

The ontogeny of human haematopoietic stem cells (HSCs) is poorly defined owing to the inability to identify HSCs as they emerge and mature at different haematopoietic sites. Here we created a single-cell transcriptome map of human haematopoietic tissues from the first trimester to birth and found that the HSC signature RUNX1HOXA9MLLT3MECOMHLFSPINK2 distinguishes HSCs from progenitors throughout gestation. In addition to the aorta-gonad-mesonephros region, nascent HSCs populated the placenta and yolk sac before colonizing the liver at 6 weeks.

H, N and C resonance assignments of the Q61H mutant of human KRAS bound to GDP.

KRAS proteins are small GTPases binding to the cell membrane and playing important roles in signal transduction. KRAS proteins form complexes with GTP and GDP to result in active and inactive conformations favouring interactions with different proteins. Mutations in KRAS have impact on the GTPase activity and some mutants are related to certain types of cancers.

Structure-activity relationship studies of allosteric inhibitors of EYA2 tyrosine phosphatase.

Human eyes absent (EYA) proteins possess Tyr phosphatase activity, which is critical for numerous cancer and metastasis promoting activities, making it an attractive target for cancer therapy. In this work, we demonstrate that the inhibitor-bound form of EYA2 does not favour binding to Mg , which is indispensable for the Tyr phosphatase activity. We further describe characterization and optimization of this class of allosteric inhibitors.

Secondary structures, dynamics, and DNA binding of the homeodomain of human SIX1.

Human sine oculis homeobox homolog (SIX) 1 contains a homeodomain (HD), which is important for binding to DNA. In this study, we carried out structural studies on the HD of human SIX1 using nuclear magnetic resonance (NMR) spectroscopy. Its secondary structures and dynamics in solution were explored.

VEGF, FGF2, and BMP4 regulate transitions of mesoderm to endothelium and blood cells in a human model of yolk sac hematopoiesis.

Exogenous growth factors play an important role in mediating hematopoietic differentiation of human pluripotent stem cells. We explored the role of different factors in early human blood cell production using blast colony formation in methylcellulose as a surrogate assay for yolk sac hematopoiesis. A reporter cell line that read out endothelial (SOX17) and hematopoietic (RUNX1C) progenitors facilitated the identification of basic fibroblast growth and vascular endothelial growth factor as critical signals for the progression of mesoderm into endothelium.

Protocol for the Generation of Definitive Hematopoietic Progenitors from Human Pluripotent Stem Cells.

This protocol offers a detailed procedure for the differentiation of human pluripotent stem cells (hPSCs) to multipotent hematopoietic progenitors that arise from SOX17 hemogenic endothelium, mimicking intra-embryonic, HOXA-positive, aorta-gonad mesonephros (AGM) hematopoiesis. The generated endothelium displays transcriptional similarities to cells sorted from human 5-week AGM, and CD45CD34RUNX1C progenitors share an accessible chromatin profile with adult hematopoietic stem cells and multipotent progenitors. Therefore, this protocol is suitable for the mechanistic study of human multipotent progenitor development and for modeling childhood leukemias.

Human yolk sac-like haematopoiesis generates , and/or dependent blood and -positive endothelium.

The genetic regulatory network controlling early fate choices during human blood cell development are not well understood. We used human pluripotent stem cell reporter lines to track the development of endothelial and haematopoietic populations in an model of human yolk-sac development. We identified SOX17CD34CD43 endothelial cells at day 2 of blast colony development, as a haemangioblast-like branch point from which SOX17CD34CD43 blood cells and SOX17CD34CD43 endothelium subsequently arose.

Powered Air Purifying Respirator (PAPR) restores the N95 face mask induced cerebral hemodynamic alterations among Healthcare Workers during COVID-19 Outbreak.

Background And Aim: COVID-19 pandemic has resulted in an unprecedented increased usage of Personal protective equipment (PPE) by healthcare-workers. PPE usage causes headache in majority of users. We evaluated changes in cerebral hemodynamics among healthcare-workers using PPE.

Expression of RUNX1-ETO Rapidly Alters the Chromatin Landscape and Growth of Early Human Myeloid Precursor Cells.

Acute myeloid leukemia (AML) is a hematopoietic malignancy caused by recurrent mutations in genes encoding transcriptional, chromatin, and/or signaling regulators. The t(8;21) translocation generates the aberrant transcription factor RUNX1-ETO (RUNX1-RUNX1T1), which by itself is insufficient to cause disease. t(8;21) AML patients show extensive chromatin reprogramming and have acquired additional mutations.

Identification and structural characterization of small molecule fragments targeting Zika virus NS2B-NS3 protease.

Zika virus (ZIKV) NS2B-NS3 protease is a validated antiviral target as it is essential for maturation of viral proteins. However, its negatively charged active site hinders the development of orthosteric small-molecule inhibitors. Fragment-based drug discovery (FBDD) is a powerful tool to generate novel chemical starting points against difficult drug targets.

Multipotent RAG1+ progenitors emerge directly from haemogenic endothelium in human pluripotent stem cell-derived haematopoietic organoids.

Defining the ontogeny of the human adaptive immune system during embryogenesis has implications for understanding childhood diseases including leukaemias and autoimmune conditions. Using RAG1:GFP human pluripotent stem cell reporter lines, we examined human T-cell genesis from pluripotent-stem-cell-derived haematopoietic organoids. Under conditions favouring T-cell development, RAG1+ cells progressively upregulated a cohort of recognized T-cell-associated genes, arresting development at the CD4+CD8+ stage.

In the absence of apoptosis, myeloid cells arrest when deprived of growth factor, but remain viable by consuming extracellular glucose.

Withdrawal of the growth factor interleukin-3 (IL-3) from IL-3-dependent myeloid cells causes them to undergo Bax/Bak1-dependent apoptosis, whereas factor-deprived BaxBak1 cells remain viable, but arrest and shrink. It was reported that withdrawal of IL-3 from BaxBak1 cells caused decreased expression of the glucose transporter Glut1, leading to reduced glucose uptake, so that arrested cells required Atg5-dependent autophagy for long-term survival. In other cell types, a decrease in Glut1 is mediated by the thioredoxin-interacting protein (Txnip), which is induced in IL-3-dependent myeloid cells when growth factor is removed.