Embracing Transparency Through Data Sharing

Human embryonic stem (hES) cells are already transforming our vision of regenerative medicine and cell replacement therapies because of their unique ability to maintain themselves indefinitely and to form all cell types in the body. hES cell lines with genomes that are predisposed to disease can be used to develop cellular models of human pathologies. The generation of disease‐specific and/or genotypically diverse human stem cell lines that can differentiate into many cell types will have great value for understanding the biology of the cell types affected in disease and analysing disease mechanisms, screening for drug candidates that can slow or prevent disease‐related degeneration as well as toxicological testing and understanding the variation between patients in their responses to therapeutics. In addition, to prepare for cell‐based therapies, new technologies for the generation of stem cell lines that are histocompatible with or specific to individual patients will provide a strategy to overcome the challenges of immune rejection. Several different methods have been developed to make hES cells; to date, these all require the use of human female egg cells as a starting point. Recently, several laboratories have reported that adult cells from human skin and other sources can be induced to revert back to earlier stages of development and exhibit stem cell‐like properties. The methods for ‘reprogramming’ have been developing rapidly but generally involve putting multiple genes into skin cells and then exposing them to specific chemical environments tailored to hES cell growth. While these cells appear to have a developmental potential that is similar to that of hES cells, they are not derived from human embryos. To distinguish these reprogrammed cells from the embryo‐sourced hES cells, they are termed induced pluripotent stem (iPS) cells. The iPS technology is the source of much optimism; »The iPS technology is the source of much …

Animal models of disease are paramount to understand retinal development, the pathophysiology of eye diseases, and to study neurodegeneration using optical coherence tomography (OCT) data. In this study, we present a comprehensive normative database of retinal thickness in C57BL6/129S mice using spectral-domain OCT data. The database covers a longitudinal period of 16 months, from 1 to 16 months of age, and provides valuable insights into retinal development and changes over time. Our findings reveal that total retinal thickness decreases with age, while the thickness of individual retinal layers and layer aggregates changes in different ways. For example, the outer plexiform layer (OPL), photoreceptor inner segments (ILS), and retinal pigment epithelium (RPE) thickened over time, whereas other retinal layers and layer aggregates became thinner. Additionally, we compare the retinal thickness of wild-type (WT) mice with an animal model of Alzheimer's disease (3 × Tg-AD) and show that the transgenic mice exhibit a decrease in total retinal thickness compared to age-matched WT mice, with statistically significant differences observed at all evaluated ages. This normative database of retinal thickness in mice will serve as a reference for future studies on retinal changes in neurodegenerative and eye diseases and will further our understanding of the pathophysiology of these conditions.

In this eighteenth (2016) Annual Review Issue of The Journal of Pathology, we present a collection of 19 invited review articles that cover different aspects of cellular and animal models of disease. These include genetically-engineered models, chemically-induced models, naturally-occurring models, and combinations thereof, with the focus on recent methodological and conceptual developments across a wide range of human diseases.

. Pelizaeus-Merzbacher disease (PMD) is a dysmyelinating disease resulting from mutations, deletions, or duplications of the proteolipid protein (PLP) gene. Distinguishing features of PMD include pleiotropy and a range of disease severities among patients. Previously, we demonstrated that, when expressed in transfected fibroblasts, many naturally occurring mutant PLP alleles encode proteins that accumulate in the endoplasmic reticulum and are not transported to the cell surface. In the present communication, we show that oligodendrocytes in an animal model of PMD, the msd mouse, accumulate Plp gene products in the perinuclear region and are unable to transport them to the cell surface. Another important aspect of disease in msd mice is oligodendrocyte cell death, which is increased by two- to threefold. We demonstrate in msd mice that this death occurs by apoptosis and show that at the time oligodendrocytes die, they have differentiated, extended processes that frequently contact axons and are expressing myelin structural proteins. Finally, we define a hypothesis that accounts for pathogenesis in most PMD patients and animal models of this disease and, moreover, can be used to develop potential therapeutic strategies for ameliorating the disease phenotype.

Neurodegenerative diseases represent a formidable challenge to global health. As advances in other areas of medicine grant healthy living into later decades of life, aging diseases such as Alzheimer's disease (AD) and other neurodegenerative disorders can diminish the quality of these additional years, owed largely to the lack of efficacious treatments and the absence of durable cures. Alzheimer's disease prevalence is predicted to more than double in the next 30 years, affecting nearly 15 million Americans, with AD-associated costs exceeding $1 billion by 2050. Delaying onset of AD and other neurodegenerative diseases is critical to improving the quality of life for patients and reducing the burden of disease on caregivers and healthcare systems. Significant progress has been made to model disease pathogenesis and identify points of therapeutic intervention. While some researchers have contributed to our understanding of the proteins and pathways that drive biological dysfunction in disease using in vitro and in vivo models, others have provided mathematical, biophysical, and computational technologies to identify potential therapeutic compounds using in silico modeling. The most exciting phase of the drug discovery process is now: by applying a target-directed approach that leverages the strengths of multiple techniques and validates lead hits using Drosophila as an animal model of disease, we are on the fast-track to identifying novel therapeutics to restore health to those impacted by neurodegenerative disease.

Gender and human chronic renal disease

Proteomics in animal models of Alzheimer's and Parkinson's diseases

Mammary cancer is among the most frequently observed canine tumors in unspayed female dogs resulting in death due to metastatic disease. These tumors are excellent models of human breast cancer but until recently there was only anecdotal evidence regarding underlying genetic defects. We recently reported expression defects in the cyclin-dependent kinase p21/Cip1 and p53 among three independent canine mammary tumor (CMT) cell lines derived from spontaneous canine mammary cancers. We investigated further defects in the same three cell lines focusing on additional tumor suppressor gene defects in cyclin-dependent kinase inhibitors. p27/KIP1 appeared normally expressed and did not appear to encode inactivating mutations. In contrast, expression of p16/INK4A was defective/absent in two cell lines and normal/slightly induced in the third cell line. To determine if defects were causative in maintaining the transformed phenotype, a p16/INK4A transgene was permanently transfected followed by selection and single cell cloning. CMT/p16 clones were characterized for transgene expression, p16 protein content and phenotype including proliferation rate, cell cycle phase distribution, contact inhibition, substrate dependent cell growth and cell morphology. All cell lines appeared unique yet clear indications of phenotype rescue due to p16/INK4A transgene complementation were observed suggesting that defects in p16 expression were present in all three. In some cases cellular senescence also appeared to be induced. These data provide evidence supporting p16/INK4A mutations as causative defects promoting transformation in canine mammary cancer and further characterizes tumor suppressor gene defects with functional consequences in these cells supporting their application as spontaneous animal models of human disease.

BackgroundNCI60 cell lines are derived from cancers of 9 tissue origins and have been invaluable in vitro models for cancer research and anti-cancer drug screen. Although extensive studies have been carried out to assess the molecular features of NCI60 cell lines related to cancer and their sensitivities to more than 100,000 chemical compounds, it remains unclear if and how well these cell lines represent or model their tumor tissues of origin. Identification and confirmation of correct origins of NCI60 cell lines are critical to their usage as model systems and to translate in vitro studies into clinical potentials. Here we report a direct comparison between NCI60 cell lines and primary tumors by analyzing global gene expression profiles.ResultsComparative analysis suggested that 51 of 59 cell lines we analyzed represent their presumed tumors of origin. Taking advantage of available clinical information of primary tumor samples used to generate gene expression profiling data, we further classified those cell lines with the correct origins into different subtypes of cancer or different stages in cancer development. For example, 6 of 7 non-small cell lung cancer cell lines were classified as lung adenocarcinomas and all of them were classified into late stages in tumor progression.ConclusionTaken together, we developed and applied a novel approach for systematic comparative analysis and integrative classification of NCI60 cell lines and primary tumors. Our results could provide guidance to the selection of appropriate cell lines for cancer research and pharmaceutical compound screenings. Moreover, this gene expression profile based approach can be generally applied to evaluate experimental model systems such as cell lines and animal models for human diseases.

Embryonic stem (ES) cells are pluripotent cells from the inner cell mass (ICM) of the blastocyst. They are capable of differentiating to various cell types, such as neural cells, cardiocytes, hepatic cells, and germ cells. The aim of this study was to establish rabbit ES cell lines as an animal model for human diseases. Blastocysts were collected from New Zealand White rabbits during Days 4 to 5 after breeding. After removal of the mucin coat and the zona pellucida by pronase, the embryos were directly cultured in ES cell medium on mitomycin C-treated mouse embryonic fibroblast (MEF) or STO feeder layers. In Experiment 1, the efficiencies of 2 different feeder layers, MEF and STO, in generating rabbit ES cell lines were compared. Six blastocysts were used for each STO and MEF feeder group. The primary ICM colonies were formed in 67% (4/6) of the cultures on the STO and 83% (5/6) on the MEF. Sixty percent of those primary colonies (3/5) were successfully grown into ES-like cell lines in the MEF feeder group. However, no cell lines were established on the STO feeder. In Experiment 2, whole blastocysts or ICMs isolated by immunosurgery were cultured to establish ES cell lines. A total of 21 blastocysts were recovered from 2 does. Eighteen whole blastocysts and 3 isolated ICMs were cultured on the MEF feeders. Twelve (67%) of the cultured whole blastocysts formed primary ICM colonies, of which 5 (42%) of the cultures continuously propagated and formed ES-like cell lines. In the immunosurgical group, 2 of the 3 isolated ICMs formed primary colonies but only 1 ES-like cell line was established. A total of 9 ES-like cell lines maintained morphological undifferentiation after 14 passages and expressed alkaline phosphatase activity. Seven of the 9 ES-like cells expressed Oct-4 and the stage-specific embryonic antigen-4 (SSEA-4) as detected by immunocytochemical staining. Two cell lines were further induced to differentiate into embryoid bodies in suspension culture. Another 3 cell lines were injected into SCID mice and one of them formed a teratoma. The competence of generating chimeric rabbits and the teratogenicity of the established ES-like cell lines are under evaluation. In conclusion, rabbit ES-like cells were efficiently generated and whole-blastocyst culturing on the MEF feeder appeared to be a preferred method for the isolation and maintenance of rabbit ES-like cell lines.

Cell lines have been widely used as models to characterize important intracellular and molecular mechanisms. Funding agencies and publishers – including the National Institutes of Health and Nature – have required researchers to authenticate human cell lines to establish their identity. Nevertheless, authentication of human cell lines has been poorly reported, let alone that of nonhuman species [1]. The use of different clones by diverse laboratories may lead to irreproducible results. Moreover, one should not assume that cell lines with the same name actually display identical characteristics, as differences in storage and culturing conditions may promote genomic variability and clonal divergence. In the reproductive field, the LβT2 [2] and αT3-1 [3] cell lines represent invaluable models for studying the regulation of pituitary gonadotropes by gonadotropin releasing hormone (GnRH) and other hormones. Both lines were produced by targeted oncogenesis in transgenic mice, with the LβT2 cells representing developmentally more mature gonadotropes than the αT3-1 cells. To establish a reference for each gonadotrope line, we requested early aliquots from the laboratory that generated them. Authentication by 27-dinucleotide and 9-tetranucleotide short tandem repeat (STR) genotyping was consistent with a mixed C57BL/6J x BALB/cJ genetic background. Spectral karyotyping revealed a variable number of chromosomes amongst cells, a result confirmed by shallow single-cell DNA sequencing in LβT2 cells. Interestingly, STR genotyping of several LβT2 batches obtained regularly throughout the past 20 years in our laboratory as well as in other laboratories identified a strain (#2) with a profile distinct from our reference line (#1). The two lines differed morphologically, with strain #2 exhibiting larger cells and extensions, whereas strain #1 displayed smaller uniform rounded cells. Moreover, the two lines showed variations in basal and GnRH-induced expression of early response and gonadotropin subunit genes. In line #1, under continuous GnRH stimulation, Egr1, Fos, and Lhb transcript levels were higher, whereas time course studies revealed lower Fos expression and no Fshb induction. Under a low-frequency regimen of pulsatile GnRH favoring Fshb induction, line #1 showed higher Egr1 transcript levels, but an absence of Fshb induction. Our results suggests that LβT2 strains exist that differ genetically and in their expression profiles. Our study demonstrates the importance of characterizing gonadotrope cell lines to improve data reproducibility, design and interpretation of gene expression experiments while continuing to use these cell lines that are important models for the study of gonadotrope physiology. [1] Almeida JL et al. PLoS Biol., 2016, 14(6):e1002476. [2] Thomas P et al. Endocrinology, 1996, 137(7): 2979-89. [3] Windle JJ et al. Mol. Endocrinology, 1990, 4(4): 597-603.

Gene therapy for colon cancer by adeno-associated viral vector-mediated transfer of survivin Cys84Ala mutant

Simple SummaryThe value of animal research has been increasingly debated, owing to high failure rates in drug development. A potential contributor to this situation is the lack of predictivity of animal models of disease. Until recently, most initiatives focused on well-known problems related to the lack of reproducibility and poor reporting standards of animal studies. Only now, more methodologies are becoming available to evaluate how translatable the data from animal models of disease are. We discuss the use and implications of several methods and tools to assess the generalisability of animal data to humans. To analyse the relevance of animal research objectively, we must (1) guarantee the experiments are conducted and reported according to best practices; (2) ensure the selection of animal models is made with a clear and detailed translational rationale behind it. Once these conditions are met, the true value of the use of animals in drug development can be finally attested.Reports of a reproducibility crisis combined with a high attrition rate in the pharmaceutical industry have put animal research increasingly under scrutiny in the past decade. Many researchers and the general public now question whether there is still a justification for conducting animal studies. While criticism of the current modus operandi in preclinical research is certainly warranted, the data on which these discussions are based are often unreliable. Several initiatives to address the internal validity and reporting quality of animal studies (e.g., Animals in Research: Reporting In Vivo Experiments (ARRIVE) and Planning Research and Experimental Procedures on Animals: Recommendations for Excellence (PREPARE) guidelines) have been introduced but seldom implemented. As for external validity, progress has been virtually absent. Nonetheless, the selection of optimal animal models of disease may prevent the conducting of clinical trials, based on unreliable preclinical data. Here, we discuss three contributions to tackle the evaluation of the predictive value of animal models of disease themselves. First, we developed the Framework to Identify Models of Disease (FIMD), the first step to standardise the assessment, validation and comparison of disease models. FIMD allows the identification of which aspects of the human disease are replicated in the animals, facilitating the selection of disease models more likely to predict human response. Second, we show an example of how systematic reviews and meta-analyses can provide another strategy to discriminate between disease models quantitatively. Third, we explore whether external validity is a factor in animal model selection in the Investigator’s Brochure (IB), and we use the IB-derisk tool to integrate preclinical pharmacokinetic and pharmacodynamic data in early clinical development. Through these contributions, we show how we can address external validity to evaluate the translatability and scientific value of animal models in drug development. However, while these methods have potential, it is the extent of their adoption by the scientific community that will define their impact. By promoting and adopting high quality study design and reporting, as well as a thorough assessment of the translatability of drug efficacy of animal models of disease, we will have robust data to challenge and improve the current animal research paradigm.

Boswellia trees, found throughout the Middle East and parts of Africa and Asia, are the source of frankincense oil. Since antiquity, frankincense has been traded as a precious commodity, but it has also been used for the treatment of chronic disease, inflammation, oral health, and microbial infection. More recently, the bioactive components of Boswellia trees have been identified and characterized for their effects on cancer, microbial infection (especially infection by oral pathogens), and inflammation. Most studies have focused on cell lines, but more recent research has also investigated effects in animal models of disease. As natural products are considered to be safer than synthetic drugs, there is growing interest in further developing the use of substances such as frankincense oil for therapeutic treatment.

The purpose of this study is to demonstrate that sumanirole is a novel dopamine receptor agonist with high in vitro and in vivo selectivity for the D(2) receptor subtype. Sumanirole, (R)-5,6-dihydro-5-(methylamino)-4H-imidazo[4,5,1-ij]quinolin-2(1H)-one (Z)-2-butenedioate (1:1), is unique; it has greater than 200-fold selectivity for the D(2) receptor subtype versus the other dopamine receptor subtypes in radioligand binding assays. In cell-based assays, sumanirole is a fully efficacious agonist, with EC(50) values between 17 and 75 nM. In animals, sumanirole elicits many physiological responses attributed to D(2)-like receptor function. In rats, sumanirole is a full agonist for elevation of striatal acetylcholine levels (ED(50) = 12.1 micromol/kg i.p.). Sumanirole s.c. dose dependently decreased plasma prolactin levels and depressed dopamine neuron firing rates in the substantia nigra pars compacta with an ED(50) of 2.3 micromol/kg i.v. This high selectivity for D(2) receptors translates into excellent locomotor stimulant activity in animal models of Parkinson's disease. In reserpinized, alpha-methyl-para-tyrosine-treated rats, sumanirole caused a significant and sustained increase in horizontal activity at doses > or =12.5 micromol/kg s.c. In unilateral 6-hydroxydopamine-lesioned rats, sumanirole caused profound, sustained rotational behavior and was substantially more efficacious than any other agonist tested. Sumanirole-stimulated rotational behavior was blocked by the dopamine receptor antagonist haloperidol. Sumanirole dose dependently improved disability scores and locomotor activities of two of three 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-lesioned monkeys. In summary, sumanirole is the first published selective D(2) receptor agonist. The compound has activity in animal models of dopamine hypofunction and has a high level of efficacy in animal models of Parkinson's disease.