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The SRY-related HMG-box family of transcription factors member SOX2 regulates stemness and pluripotency in embryonic stem cells and plays important roles during early embryogenesis. More recently,SOX2 expression was documented in several tumor types including ovarian carcinoma,suggesting an involvement of SOX2 in regulation of cancer stem cells (CSC). Intriguingly,however,studies exploring the predictive value of SOX2 protein expression with respect to histopathologic and clinical parameters report contradictory results in individual tumors,indicating that SOX2 may play tumor-specific roles. In this report,we analyze the functional relevance of SOX2 expression in human ovarian carcinoma. We report that in human serous ovarian carcinoma (SOC) cells,SOX2 expression increases the expression of CSC markers,the potential to form tumor spheres,and the in vivo tumor-initiating capacity,while leaving cellular proliferation unaltered. Moreover,SOX2-expressing cells display enhanced apoptosis resistance in response to conventional chemotherapies and TRAIL. Hence,our data show that SOX2 associates with stem cell state in ovarian carcinoma and induction of SOX2 imposes CSC properties on SOC cells. We propose the existence of SOX2-expressing ovarian CSCs as a mechanism of tumor aggressiveness and therapy resistance in human SOC. View Publication

Human embryonic stem cell line BJNhem20-OCIAD1-Tet-On was generated using non-viral method. The constructs pCAG-Tet-On and pTRE-Tight vector driving OCIAD1 expression were transfected using microporation procedure. pCAG-Tet-On cells can be used for inducible expression of any coding sequence cloned into pTRE-Tight vector. For example,in human embryonic stem cells,Tet-On system has been used to generate SOX2 overexpression cell line (Adachi et al.,2010). View Publication

Mobile sensing based on the integration of microfluidic device and smartphone,so-called MS2 technology,has enabled many applications over recent years,and continues to stimulate growing interest in both research communities and industries. In particular,it has been envisioned that MS2 technology can be developed for various cell functional assays to enable basic research and clinical applications. Toward this direction,in this paper,we describe the development of a MS2-based cell functional assay for testing cell migration (the Mkit). The system is constructed as an integrated test kit,which includes microfluidic chips,a smartphone-based imaging platform,the phone apps for image capturing and data analysis,and a set of reagent and accessories for performing the cell migration assay. We demonstrated that the Mkit can effectively measure purified neutrophil and cancer cell chemotaxis. Furthermore,neutrophil chemotaxis can be tested from a drop of whole blood using the Mkit with red blood cell (RBC) lysis. The effects of chemoattractant dose and gradient profile on neutrophil chemotaxis were also tested using the Mkit. In addition to research applications,we demonstrated the effective use of the Mkit for on-site test at the hospital and for testing clinical samples from chronic obstructive pulmonary disease patient. Thus,this developed Mkit provides an easy and integrated experimental platform for cell migration related research and potential medical diagnostic applications. View Publication

Transplantation of Defined Populations of Differentiated Human Neural Stem Cell Progeny View Publication

Sustained,indolent immune injury of the vasculature of a heart transplant limits long-term graft and recipient survival. This injury is mitigated by a poorly characterized,maladaptive repair response. Vascular endothelial cells respond to proangiogenic cues in the embryo by differentiation to specialized phenotypes,associated with expression of apelin. In the adult,the role of developmental proangiogenic cues in repair of the established vasculature is largely unknown. We found that human and minor histocompatibility-mismatched donor mouse heart allografts with alloimmune-mediated vasculopathy upregulated expression of apelin in arteries and myocardial microvessels. In vivo,loss of donor heart expression of apelin facilitated graft immune cell infiltration,blunted vascular repair,and worsened occlusive vasculopathy in mice. In vitro,an apelin receptor agonist analog elicited endothelial nitric oxide synthase activation to promote endothelial monolayer wound repair and reduce immune cell adhesion. Thus,apelin acted as an autocrine growth cue to sustain vascular repair and mitigate the effects of immune injury. Treatment with an apelin receptor agonist after vasculopathy was established markedly reduced progression of arterial occlusion in mice. Together,these initial data identify proangiogenic apelin as a key mediator of coronary vascular repair and a pharmacotherapeutic target for immune-mediated injury of the coronary vasculature. View Publication

Diabetes involves the death or dysfunction of pancreatic ?-cells. Analysis of bulk sequencing from human samples and studies using in vitro and in vivo models suggest that endoplasmic reticulum and inflammatory signaling play an important role in diabetes progression. To better characterize cell type-specific stress response,we perform multiplexed single-cell RNA sequencing to define the transcriptional signature of primary human islet cells exposed to endoplasmic reticulum and inflammatory stress. Through comprehensive pair-wise analysis of stress responses across pancreatic endocrine and exocrine cell types,we define changes in gene expression for each cell type under different diabetes-associated stressors. We find that ?-,?-,and ductal cells have the greatest transcriptional response. We utilize stem cell-derived islets to study islet health through the candidate gene CIB1,which was upregulated under stress in primary human islets. Our findings provide insights into cell type-specific responses to diabetes-associated stress and establish a resource to identify targets for diabetes therapeutics. Endoplasmic reticulum and inflammatory stress are associated with diabetes. Maestas et al. use single-cell sequencing to profile primary human islets under stress and identified tissue and cell-type responses. View Publication

Cholesterol is an essential plasma membrane component,and altered cholesterol metabolism has been linked to cholesterol accumulation in the airways of COPD and cystic fibrosis patients. However,its role in airway epithelial differentiation is not well understood. Tandem mass spectrometry-based proteomic analysis of differentiating primary human bronchial epithelial cells (phBECs) revealed an overall inhibition of the cholesterol biosynthesis pathway. We hypothesized that excess cholesterol impairs the differentiation of phBECs into a fully functional bronchial epithelium. PhBECs were differentiated in the presence of 80 µM cholesterol for 21 days,the main airway cell type populations monitored using qRT-PCR and immunofluorescent stainings,and epithelial barrier integrity was analyzed via transepithelial electrical resistance measurements. Chronic cholesterol exposure led to a significant increase in CC10 + secretory cells at the expense of ciliated cells. Pathway enrichment analysis suggested the tumor protein p53 as a master regulator of genes during normal differentiation of phBECs. Chronic cholesterol exposure drastically impaired the nuclear translocation of p53. Our findings suggest that this inhibition underlies the cholesterol-induced expansion of CC10 + secretory cell populations at the expense of ciliated cells. In conclusion,we identify cholesterol as an important regulator of normal bronchial epithelial cell differentiation through inhibition of p53 nuclear translocation. View Publication

Drug resistance and relapse remain key challenges in pancreatic cancer. Here,we have used RNA sequencing (RNA-seq),chromatin immunoprecipitation (ChIP)-seq,and genome-wide CRISPR analysis to map the molecular dependencies of pancreatic cancer stem cells,highly therapy-resistant cells that preferentially drive tumorigenesis and progression. This integrated genomic approach revealed an unexpected utilization of immuno-regulatory signals by pancreatic cancer epithelial cells. In particular,the nuclear hormone receptor retinoic-acid-receptor-related orphan receptor gamma (ROR$\gamma$),known to drive inflammation and T cell differentiation,was upregulated during pancreatic cancer progression,and its genetic or pharmacologic inhibition led to a striking defect in pancreatic cancer growth and a marked improvement in survival. Further,a large-scale retrospective analysis in patients revealed that ROR$\gamma$ expression may predict pancreatic cancer aggressiveness,as it positively correlated with advanced disease and metastasis. Collectively,these data identify an orthogonal co-option of immuno-regulatory signals by pancreatic cancer stem cells,suggesting that autoimmune drugs should be evaluated as novel treatment strategies for pancreatic cancer patients. View Publication

Ca(2+) influx through voltage-gated Ca(2+) channels,especially the L-type (Ca(v)1),activates downstream signaling to the nucleus that affects gene expression and,consequently,cell fate. We hypothesized that these Ca(2+) signals may also influence the neuronal differentiation of neural stem/progenitor cells (NSCs) derived from the brain cortex of postnatal mice. We first studied Ca(2+) transients induced by membrane depolarization in Fluo 4-AM-loaded NSCs using confocal microscopy. Undifferentiated cells (nestin(+)) exhibited no detectable Ca(2+) signals whereas,during 12 days of fetal bovine serum-induced differentiation,neurons (beta-III-tubulin(+)/MAP2(+)) displayed time-dependent increases in intracellular Ca(2+) transients,with DeltaF/F ratios ranging from 0.4 on day 3 to 3.3 on day 12. Patch-clamp experiments revealed similar correlation between NSC differentiation and macroscopic Ba(2+) current density. These currents were markedly reduced (-77%) by Ca(v)1 channel blockade with 5 microm nifedipine. To determine the influence of Ca(v)1-mediated Ca(2+) influx on NSC differentiation,cells were cultured in differentiative medium with either nifedipine (5 microm) or the L-channel activator Bay K 8644 (10 microm). The latter treatment significantly increased the percentage of beta-III-tubulin(+)/MAP2(+) cells whereas nifedipine produced opposite effects. Pretreatment with nifedipine also inhibited the functional maturation of neurons,which responded to membrane depolarization with weak Ca(2+) signals. Conversely,Bay K 8644 pretreatment significantly enhanced the percentage of responsive cells and the amplitudes of Ca(2+) transients. These data suggest that NSC differentiation is strongly correlated with the expression of voltage-gated Ca(2+) channels,especially the Ca(v)1,and that Ca(2+) influx through these channels plays a key role in promoting neuronal differentiation. View Publication

Somatic cell nuclear transfer allows trans-acting factors present in the mammalian oocyte to reprogram somatic cell nuclei to an undifferentiated state. We show that four factors (OCT4,SOX2,NANOG,and LIN28) are sufficient to reprogram human somatic cells to pluripotent stem cells that exhibit the essential characteristics of embryonic stem (ES) cells. These induced pluripotent human stem cells have normal karyotypes,express telomerase activity,express cell surface markers and genes that characterize human ES cells,and maintain the developmental potential to differentiate into advanced derivatives of all three primary germ layers. Such induced pluripotent human cell lines should be useful in the production of new disease models and in drug development,as well as for applications in transplantation medicine,once technical limitations (for example,mutation through viral integration) are eliminated. View Publication

Adult hematopoietic stem cells (HSCs) are routinely used to reconstitute hematopoiesis after myeloablation; however,transplantation efficacy and multilineage reconstitution can be limited by inadequate HSC number,or poor homing,engraftment,or self-renewal. Here we report that mouse and human HSCs express prostaglandin E2 (PGE2) receptors,and that short-term ex vivo exposure of HSCs to PGE2 enhances their homing,survival,and proliferation,resulting in increased long-term repopulating cell (LTRC) and competitive repopulating unit (CRU) frequency. HSCs pulsed with PGE2 are more competitive,as determined by head-to-head comparison in a competitive transplantation model. Enhanced HSC frequency and competitive advantage is stable and maintained upon serial transplantation,with full multilineage reconstitution. PGE2 increases HSC CXCR4 mRNA and surface expression,enhances their migration to SDF-1 in vitro and homing to bone marrow in vivo,and stimulates HSC entry into and progression through cell cycle. In addition,PGE2 enhances HSC survival,associated with an increase in Survivin mRNA and protein expression and reduction in intracellular active caspase-3. Our results define novel mechanisms of action whereby PGE2 enhances HSC function and supports a strategy to use PGE2 to facilitate hematopoietic transplantation. View Publication

CD200 is a transmembrane protein broadly expressed on a variety of cell types,which delivers immunoregulatory signals through binding to receptors (CD200Rs) expressed on monocytes/myeloid cells and T lymphocytes. Signals delivered through the CD200:CD200R axis have been shown to play an important role in the regulation of anti-tumor immunity,and overexpression of CD200 has been reported in a number of malignancies,including CLL,as well as on cancer stem cells. We investigated the effect of CD200 blockade in vitro on a generation of CTL responses against a poorly immunogenic CD200+ lymphoma cell line and fresh cells obtained from CLL patients using anti-CD200 mAb and CD200-specific siRNAs. Suppression of functional expression of CD200 augmented killing of the CD200+ cells,as well as production of the inflammatory cytokines IFN-gamma and TNF-alpha by effector PBMCs. Killing was mediated by CD8+ cytotoxic T cells,and CD4+ T cells play an important role in CD200-mediated suppression of CTL responses. Our data suggest that CD200 blockade may represent a novel approach to clinical treatment of CLL. View Publication