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Concept: HeLa

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Primary human fallopian tube secretory epithelial cell (FTSEC) cultures are useful for studying normal fallopian tube epithelial biology, as well as for developing models of fallopian tube disease, such as cancer. Because of the limited ability of primary human FTSECs to proliferate in vitro, it is necessary to immortalize them in order to establish a cell line that is suitable for long-term culture and large-scale in vitro experimentation. This protocol describes the isolation of FTSECs from human fallopian tube tissue, conditions for primary FTSEC culture and techniques for establishing immortal FTSEC lines. The entire process, from primary cell isolation to establishment of an immortal cell line, may take up to 2 months. Once established, immortal FTSECs can typically be maintained for at least 30 passages.

Concepts: HeLa, Fallopian tube, Cell culture, Cell, Cell biology, Skin, Epithelium

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A chemical investigation of the EtOAc-soluble fraction from the ethanol extract of the medullae of Juncus effusus led to the isolation of three new 9,10-dihydrophenanthrenes, juncuenins E-G (1-3); two new phenanthrenes, dehydrojuncuenins D-E (4-5); one new feruloylated glycoside (6); and one known 9,10-dihydrophenanthrene (7). The structures of these compounds were determined by analyzing their spectroscopic data. Metabolites 1-4 and 7 were further evaluated for their in vitro cytotoxic activities against seven human cancer lines (A549, MCF-7, BEL-7402, HeLa, COLO205, BGC-823, and SK-OV-3). Among them, compound 1 exhibited weak cytotoxicity against MCF-7 and HeLa cell lines. Compound 7 showed moderate cytotoxicity against MCF-7 and HeLa cell lines, with IC50 values of 9.17 and 19.6 µM, respectively.

Concepts: Cytotoxicity, Juncus effusus, Chemical compound, Toxicology, Cell lines, Cell culture, Cell, HeLa

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The uptake of calcium phosphate nanoparticles (diameter 120 nm) with different charge by HeLa cells was studied by flow cytometry. The amount of uptaken nanoparticles increased with increasing concentration of nanoparticles in the cell culture medium. Several inhibitors of endocytosis and macropinocytosis were applied to elucidate the uptake mechanism of nanoparticles into HeLa cells: Wortmannin, LY294002, nocodazole, chlorpromazine, and nystatin. Wortmannin and LY294002 strongly reduced the uptake of anionic nanoparticles, which indicates macropinocytosis as uptake mechanism. For cationic nanoparticles, the uptake was reduced to a lesser extent, indicating a different uptake mechanism. The localisation of nanoparticles inside the cells was investigated by conjugating them with the pH-sensitive dye SNARF-1. The nanoparticles were localised in lysosomes after 3 h of incubation.

Concepts: Bacteria, Endocytosis, Growth medium, Flow cytometry, HeLa, Cell, Cell biology, Cell culture

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Two new benzoxazines were isolated from Streptomyces griseus (HKI 0545) and assigned as chandrananimycin E (1) and dandamycin (2). Although a number of phenoxazinone-type compounds have been reported from nature, phenoxazines are rarer, and carbon substitution at N-10 such as in 1 is unprecedented. The cyclopentene-containing ring structure of dandamycin (2) is also unique. Chandrananimycin E (1) was found to possess moderate antiproliferative activity against HUVEC cells (GI50 35.3 μM) and weak cytotoxic activity towards HeLa cells (CC50 56.9 μM). Dandamycin showed neither antiproliferative activity nor cytotoxicity towards these cell lines. Structure activity comparisons with phenoxazinones isolated from S. griseus HKI 0545 suggested that the alteration of the core ring systems in 1 and 2 diminishes their activity. Natural products 1 and 2 are interesting additions to the rich secondary metabolome of S. griseus and constitute an important addition to the body of knowledge on phenoxazinone-derived metabolites.The Journal of Antibiotics advance online publication, 18 February 2015; doi:10.1038/ja.2015.10.

Concepts: Bacteria, Streptomyces, HeLa, Cytotoxicity, Addition, Cell, Cell culture, Streptomyces griseus

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The present study aimed to investigate the phenolic profile of second grade date extracts and evaluate their antimicrobial and cytotoxic activities with regard to some pathogenic microorganisms. Phenolic content was analyzed by HPLC. Antimicrobial activity was evaluated by the agar disk diffusion method, and in vitro cytotoxic activity was examined by cell proliferation assay. The results revealed that second grade dates presented three benzoic acids, five cinnamic acids and two flavonoids, with the predominance of ρ-coumaric acid (1998.80μg/100g). The antimicrobial activities showed that the date extracts were active against Gram (+) and Gram (-) bacteria, showing marked activity against Escherichia coli with an inhibition zone of 25mm. Cytotoxicity assays showed that the date extracts were able to inhibit the proliferation of HeLa cell lines. The results confirmed that the date extracts were rich in biologically active compounds that are highly valued in the functional food and nutraceutical industries.

Concepts: Biotechnology, Escherichia coli, Cell culture, Cytotoxicity, Microbiology, HeLa, Cell, Bacteria

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BACKGROUND: The global expansion of biobanks has led to a range of bioethical concerns related to consent, privacy, control, ownership, and disclosure. As an opportunity to engage broader audiences on these concerns, bioethicists have welcomed the commercial success of Rebecca Skloot’s 2010 bestselling book The Immortal Life of Henrietta Lacks. To assess the impact of the book on discussion within the media and popular culture more generally, we systematically analyzed the ethics-related themes emphasized in reviews and articles about the book, and in interviews and profiles of Skloot. METHODS: We conducted a content analysis of a population of relevant English-language articles and transcripts (n = 125) produced by news organizations and publications in the U.S., Canada, Great Britain/Ireland, and Australia/New Zealand. We scored each article for the emphasis and appearance of 9 ethics-related themes. These were informed consent, welfare of the vulnerable, compensation, scientific progress, control/access, accountability/oversight, privacy, public education, and advocacy. RESULTS: The informed consent theme dominated media discussion, with almost 39.2 percent of articles/transcripts featuring the theme as a major focus and 44.8 percent emphasizing the theme as a minor focus. Other prominent themes and frames of reference focused on the welfare of the vulnerable (18.4 percent major emphasis; 36.0 percent minor emphasis), and donor compensation (19.2 percent major; 52.8 percent minor). Ethical themes that comprised a second tier of prominence included those of scientific progress, control/access, and accountability/oversight. The least prominent themes were privacy, public education, and advocacy. CONCLUSIONS: The book has been praised as an opportunity to elevate public discussion of bioethics, but such claims should be re-considered. The relatively narrow focus on informed consent in the media discussion generated by Skloot’s book may limit the ability of ethicists and advocates to elevate attention to donor control, compensation, patenting, privacy, and other ethical issues. Still, ethicists should view the book and a pending major TV film translation as opportunities to highlight through media outreach, consultation exercises and public forums a broader range of bioethical concerns that would otherwise be under-emphasized in news coverage. Such efforts, however, need to be carefully planned and evaluated.

Concepts: Key signature, Organ donation, HeLa, Bioethics, Informed consent, Rebecca Skloot, Henrietta Lacks, Ethics

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The HeLa cell line was established in 1951 from cervical cancer cells taken from a patient, Henrietta Lacks. This was the first successful attempt to immortalize human-derived cells in vitro. The robust growth and unrestricted distribution of HeLa cells resulted in its broad adoption–both intentionally and through widespread cross-contamination–and for the past 60 years it has served a role analogous to that of a model organism. The cumulative impact of the HeLa cell line on research is demonstrated by its occurrence in more than 74,000 PubMed abstracts (approximately 0.3%). The genomic architecture of HeLa remains largely unexplored beyond its karyotype, partly because like many cancers, its extensive aneuploidy renders such analyses challenging. We carried out haplotype-resolved whole-genome sequencing of the HeLa CCL-2 strain, examined point- and indel-mutation variations, mapped copy-number variations and loss of heterozygosity regions, and phased variants across full chromosome arms. We also investigated variation and copy-number profiles for HeLa S3 and eight additional strains. We find that HeLa is relatively stable in terms of point variation, with few new mutations accumulating after early passaging. Haplotype resolution facilitated reconstruction of an amplified, highly rearranged region of chromosome 8q24.21 at which integration of the human papilloma virus type 18 (HPV-18) genome occurred and that is likely to be the event that initiated tumorigenesis. We combined these maps with RNA-seq and ENCODE Project data sets to phase the HeLa epigenome. This revealed strong, haplotype-specific activation of the proto-oncogene MYC by the integrated HPV-18 genome approximately 500 kilobases upstream, and enabled global analyses of the relationship between gene dosage and expression. These data provide an extensively phased, high-quality reference genome for past and future experiments relying on HeLa, and demonstrate the value of haplotype resolution for characterizing cancer genomes and epigenomes.

Concepts: Cell culture, Mutation, DNA, Gene expression, Cancer, HeLa, Gene, Human papillomavirus

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Studies have shown that podocytes and renal tubular epithelial cells from patients with HIV-associated nephropathy (HIVAN) express HIV-1 transcripts, suggesting that productive infection of renal epithelial cells precipitates development of HIVAN. However, podocytes and renal tubular epithelial cells do not express CD4 receptors, and it is unclear how these cells become productively infected in vivo We investigated the mechanisms underlying the infection by HIV-1 of podocytes cultured from the urine of children with HIVAN. We observed low-level productive infection on exposure of these cells to primary cell-free HIV-1 supernatants. However, envelope-defective recombinant HIV-1 did not infect the renal epithelial cell lines. Moreover, treatment of podocytes to inhibit endocytic transport or dynamin activity or remove cell surface heparan sulfate proteoglycans reduced infection efficiency. Transfection of CD4- 293T cells with a cDNA expression library developed from a podocyte cell line derived from a child with HIVAN led to the identification of TNF-α as a possible mediator of HIV-1 infection. Overexpression of transmembrane TNF-α in cultured CD4- renal tubular epithelial cells, 293T cells, and HeLa cells enabled the infection of these cells; exposure to soluble TNF-α did not. Immunohistochemistry showed TNF-α expression in podocytes of renal sections from children with HIVAN. Furthermore, we found that TNF-α enhanced NF-κB activation and integration of HIV-1 into the podocyte DNA. Finally, inhibition of dynamin activity blocked TNF-α-mediated infection. These data establish a role for transmembrane TNF-α in facilitating the viral entry and integration of HIV-1 into the DNA of renal epithelial cells.

Concepts: Basement membrane, HeLa, Protein, Cell, DNA, Gene expression, Cell culture, Epithelium

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The emergence of resistance to last resort antibiotics is a public health concern of global scale. Besides direct person-to-person propagation, environmental pathways might contribute to the dissemination of antibiotic-resistant bacteria and antibiotic resistance genes (ARGs). Here, we describe the incidence of blaNDM-1, a gene conferring resistance to carbapenems, in the wastewater of Jeddah city over a one-year period. blaNDM-1 was detected at concentrations ranging from 10(4) to 10(5) copies per m(3) of untreated wastewater during the entire monitoring period. These results indicate the ubiquity and high incidence of blaNDM-1 in the local wastewater. To track the bacteria carrying blaNDM-1, we isolated Escherichia coli PI7, a strain of the sequence type ST101, from wastewater around the Hajj event in October 2013. Genome sequencing of this strain revealed an extensive repertoire of ARGs as well as virulence and invasive traits. These traits were further confirmed by antibiotic resistance profiling and in-vitro cell internalization in HeLa cell cultures. Given that this strain remains viable even after a certain duration in the sewerage, and that Jeddah lacks a robust sanitary infrastructure to fully capture all generated sewage, the presence of this bacterium in the untreated wastewater would represent a potential hazard to the local public health. To the best of our knowledge, this is the first report of a blaNDM-1-positive E. coli isolated from a non-nosocomial environment in Saudi Arabia, and may set a preceding concern for the need to establish an improved surveillance for carbapenem-resistant E. coli in the country and nearby regions.

Concepts: HeLa, Saudi Arabia, Evolution, Mecca, Gene, Escherichia coli, Bacteria, Antibiotic resistance

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Aneuploidy and structural variations (SVs) generate cancer genomes containing a mixture of rearranged genomic segments with extensive somatic copy number alterations. However, existing methods can identify either SVs or allele-specific copy number alterations but not both simultaneously, which provides a limited view of cancer genome structure. Here, we introduce Weaver, an algorithm for the quantification and analysis of allele-specific copy numbers of SVs. Weaver uses a Markov random field to estimate joint probabilities of allele-specific copy numbers of SVs and their inter-connectivity based on paired-end whole-genome sequencing data. Weaver also predicts the timing of SVs relative to chromosome amplifications. We demonstrate the accuracy of Weaver using simulations and findings from whole-genome optical mapping. We apply Weaver to generate allele-specific copy numbers of SVs for MCF-7 and HeLa cell lines and identify recurrent SV patterns in 44 TCGA ovarian cancer whole-genome sequencing datasets. Our approach provides a more complete assessment of the complex genomic architectures inherent to many cancer genomes.

Concepts: Cell lines, Human genome, Copy number variation, Cell culture, Genetics, Genome, HeLa, Gene