Isolation of single circulating trophoblasts from maternal circulation for noninvasive fetal copy number variant profiling.

OBJECTIVE: To develop a multi-step workflow for the isolation of circulating extravillous trophoblasts (cEVTs) by describing the key steps enabling a semi-automated process, including a proprietary algorithm for fetal cell origin genetic confirmation and copy number variant (CNV) detection. METHODS: Determination of the limit of detection (LoD) for submicroscopic CNV was performed by serial experiments with genomic DNA and single cells from Coriell cell line biobank with known imbalances of different sizes. A pregnancy population of 372 women was prospectively enrolled and blindly analyzed to evaluate the current workflow. RESULTS: An LoD of 800 Kb was demonstrated with Coriell cell lines. This level of resolution was confirmed in the clinical cohort with the identification of a pathogenic CNV of 800 Kb, also detected by chromosomal microarray. The mean number of recovered cEVTs was 3.5 cells per sample with a significant reverse linear trend between gestational age and cEVT recovery rate and number of recovered cEVTs. In twin pregnanices, evaluation of zygosity, fetal sex and copy number profiling was performed in each individual cell. CONCLUSION: Our semi-automated methodology for the isolation and single-cell analysis of cEVTS supports the feasibility of a cell-based noninvasive prenatal test for fetal genomic profiling.

In Vitro Testing of Biomaterials for Neural Repair: Focus on Cellular Systems and High-Content Analysis.

Biomimetic materials are designed to stimulate specific cellular responses at the molecular level. To improve the soundness of in vitro testing of the biological impact of new materials, appropriate cell systems and technologies must be standardized also taking regulatory issues into consideration. In this study, the biological and molecular effects of different scaffolds on three neural systems, that is, the neural cell line SH-SY5Y, primary cortical neurons, and neural stem cells, were compared. The effect of poly(L-lactic acid) scaffolds having different surface geometry (conventional two-dimensional seeding flat surface, random or aligned fibers as semi3D structure) and chemical functionalization (laminin or ECM extract) were studied. The endpoints were defined for efficacy (i.e., neural differentiation and neurite elongation) and for safety (i.e., cell death/survival) using high-content analysis. It is demonstrated that (i) the definition of the biological properties of biomaterials is profoundly influenced by the test system used; (ii) the definition of the in vitro safety profile of biomaterials for neural repair is also influenced by the test system; (iii) cell-based high-content screening may well be successfully used to characterize both the efficacy and safety of novel biomaterials, thus speeding up and improving the soundness of this critical step in material science having medical applications.

Digital Sorting of Pure Cell Populations Enables Unambiguous Genetic Analysis of Heterogeneous Formalin-Fixed Paraffin-Embedded Tumors by Next Generation Sequencing.

Precision medicine in oncology requires an accurate characterization of a tumor molecular profile for patient stratification. Though targeted deep sequencing is an effective tool to detect the presence of somatic sequence variants, a significant number of patient specimens do not meet the requirements needed for routine clinical application. Analysis is hindered by contamination of normal cells and inherent tumor heterogeneity, compounded with challenges of dealing with minute amounts of tissue and DNA damages common in formalin-fixed paraffin-embedded (FFPE) specimens. Here we present an innovative workflow using DEPArray™ system, a microchip-based digital sorter to achieve 100%-pure, homogenous subpopulations of cells from FFPE samples. Cells are distinguished by fluorescently labeled antibodies and DNA content. The ability to address tumor heterogeneity enables unambiguous determination of true-positive sequence variants, loss-of-heterozygosity as well as copy number variants. The proposed strategy overcomes the inherent trade-offs made between sensitivity and specificity in detecting genetic variants from a mixed population, thus rescuing for analysis even the smaller clinical samples with low tumor cellularity.

In vitro differentiation of porcine aortic vascular precursor cells to endothelial and vascular smooth muscle cells.

Recent findings suggest that progenitor and multipotent mesenchymal stromal cells (MSCs) are associated with vascular niches. Cells displaying mesenchymal properties and differentiating to whole components of a functional blood vessel, including endothelial and smooth muscle cells, can be defined as vascular stem cells (VSCs). Recently, we isolated a population of porcine aortic vascular precursor cells (pAVPCs), which have MSC- and pericyte-like properties. The aim of the present work was to investigate whether pAVPCs possess VSC-like properties and assess their differentiation potential toward endothelial and smooth muscle lineages. pAVPCs, maintained in a specific pericyte growth medium, were cultured in high-glucose DMEM + 10% FBS (long-term medium, LTM) or in human endothelial serum-free medium + 5% FBS and 50 ng/ml of hVEGF (endothelial differentiation medium, EDM). After 21 days of culture in LTM, pAVPCs showed an elongated fibroblast-like morphology, and they seem to organize in cord-like structures. qPCR analysis of smooth muscle markers [α-smooth muscle actin (α-SMA), calponin, and smooth muscle myosin (SMM) heavy chain] showed a significant increment of the transcripts, and immunofluorescence analysis confirmed the presence of α-SMA and SMM proteins. After 21 days of culture in EDM, pAVPCs displayed an endothelial cell-like morphology and revealed the upregulation of the expression of endothelial markers (CD31, vascular endothelial-cadherin, von Willebrand factor, and endothelial nitric oxide synthase) showing the CD31-typical pattern. In conclusion, pAVPCs could be defined as a VSC-like population considering that, if they are maintained in a specific pericyte medium, they express MSC markers, and they have, in addition to the classical mesenchymal trilineage differentiation potential, the capacity to differentiate in vitro toward the smooth muscle and the endothelial cell phenotypes.

Cells derived from porcine aorta tunica media show mesenchymal stromal-like cell properties in in vitro culture.

Several studies have already described the presence of specialized niches of precursor cells in vasculature wall, and it has been shown that these populations share several features with mesenchymal stromal cells (MSCs). Considering the relevance of MSCs in the cardiovascular physiopathology and regenerative medicine, and the usefulness of the pig animal model in this field, we reported a new method for MSC-like cell isolation from pig aorta. Filling the vessel with a collagenase solution for 40 min, all endothelial cells were detached and discarded and then collagenase treatment was repeated for 4 h to digest approximately one-third of the tunica media. The ability of our method to select a population of MSC-like cells from tunica media could be ascribed in part to the elimination of contaminant cells from the intimal layer and in part to the overnight culture in the high antibiotic/antimycotic condition and to the starvation step. Aortic-derived cells show an elongated, spindle shape, fibroblast-like morphology, as reported for MSCs, stain positively for CD44, CD56, CD90, and CD105; stain negatively for CD34 and CD45; and express CD73 mRNA. Moreover, these cells show the classical mesenchymal trilineage differentiation potential. Under our in vitro culture conditions, aortic-derived cells share some phenotypical features with pericytes and are able to take part in the formation of network-like structures if cocultured with human umbilical vein endothelial cells. In conclusion, our work reports a simple and highly suitable method for obtaining large numbers of precursor MSC-like cells derived from the porcine aortic wall.

Azetidinone-retinoid hybrids: synthesis and differentiative effects.

As a part of a systematic investigation on the synthesis and biological activities of new ß-lactam compounds, we examined ß-lactam candidates 1, 2E and 2Z and their ability to induce cell proliferation or differentiation. Azetidinone 1 was chosen for its activity (previously evaluated) as selective HDAC8 inhibitor, whereas ß-lactams 2E and 2Z were designed to have a hybrid retinoid-azetidinone structure, de novo synthesized and fully characterized. Biological activities were determined in cellular assays on neuroblastoma cells SH-SY5Y. Azetidinone 1, 2E and 2Z led to a moderate effect in decreasing SH-SY5Y cell proliferation and ß-lactams 2E and 2Z induced an early stage differentiation. The present results uncovered a new role of specifically designed ß-lactam compounds in epigenetic regulation.

From the multifactorial nature of Alzheimer`s disease to multitarget therapy: the contribution of the translational approach.

The drug discovery for disease-modifying agents in Alzheimer disease (AD) is facing a failure of clinical trials with drugs based on two driving hypotheses, i.e. the cholinergic and amyloidogenic hypotheses. In this article we recapitulate the main aspects of AD pathology, focusing on possible mechanisms for synaptic dysfunction, neurodegeneration and inflammation. We then present the pharmacological and neurobiological profile of a novel compound (CHF5074) showing both anti-inflammatory and gamma-secretase modulatory activities, discussing the possible time-window for effective treatment in an AD transgenic mouse model. Finally, the concept of cognitive reserve is introduced as possible target for preventive therapies.

Multi-target action of the novel anti-Alzheimer compound CHF5074: in vivo study of long term treatment in Tg2576 mice.

BACKGROUND: Alzheimer disease is a multifactorial disorder characterized by the progressive deterioration of neuronal networks. The pathological hallmarks includes extracellular amyloid plaques and intraneuronal neurofibrillary tangles, but the primary cause is only partially understood. Thus, there is growing interest in developing agents that might target multiple mechanisms leading to neuronal degeneration. CHF5074 is a nonsteroidal anti-inflammatory derivative that has been shown to behave as a γ-secretase modulator in vitro and to inhibit plaque deposition and to reverse memory deficit in vivo in transgenic mouse models of Alzheimer's disease (AD). In the present study, the effects of a long-term (13-month) treatment with CHF5074 on indicators of brain functionality and neurodegeneration in transgenic AD mice (Tg2576) have been assessed and compared with those induced by a prototypical γ-secretase inhibitor (DAPT). RESULTS: To this end, plaque-free, 6-month-old Tg2576 mice and wild-type littermates were fed with a diet containing CHF5074 (125 and 375 ppm/day), DAPT (375 ppm/day) or vehicle for 13 months. The measured indicators included object recognition memory, amyloid burden, brain oligomeric and plasma Aß levels, intraneuronal Aß, dendritic spine density/morphology, neuronal cyclin A positivity and activated microglia. Tg2576 mice fed with standard diet displayed an impairment of recognition memory. This deficit was completely reverted by the higher dose of CHF5074, while no effects were observed in DAPT-treated mice. Similarly, amyloid plaque burden, microglia activation and aberrant cell cycle events were significantly affected by CHF5074, but not DAPT, treatment. Both CHF5074 and DAPT reduced intraneuronal Aß content, also increasing Aß40 and Aß42 plasma levels. CONCLUSIONS: This comparative analysis revealed a profoundly diverse range of clinically relevant effects differentiating the multifunctional anti-inflammatory derivative CHF5074 from the γ-secretase inhibitor DAPT and highlighted unique mechanisms and potential targets that may be crucial for neuroprotection in mouse models of AD.

Pharmacotherapy with fluoxetine restores functional connectivity from the dentate gyrus to field CA3 in the Ts65Dn mouse model of down syndrome.

Down syndrome (DS) is a high-incidence genetic pathology characterized by severe impairment of cognitive functions, including declarative memory. Impairment of hippocampus-dependent long-term memory in DS appears to be related to anatomo-functional alterations of the hippocampal trisynaptic circuit formed by the dentate gyrus (DG) granule cells - CA3 pyramidal neurons - CA1 pyramidal neurons. No therapies exist to improve cognitive disability in individuals with DS. In previous studies we demonstrated that pharmacotherapy with fluoxetine restores neurogenesis, granule cell number and dendritic morphology in the DG of the Ts65Dn mouse model of DS. The goal of the current study was to establish whether treatment rescues the impairment of synaptic connectivity between the DG and CA3 that characterizes the trisomic condition. Euploid and Ts65Dn mice were treated with fluoxetine during the first two postnatal weeks and examined 45-60 days after treatment cessation. Untreated Ts65Dn mice had a hypotrophyc mossy fiber bundle, fewer synaptic contacts, fewer glutamatergic contacts, and fewer dendritic spines in the stratum lucidum of CA3, the terminal field of the granule cell projections. Electrophysiological recordings from CA3 pyramidal neurons showed that in Ts65Dn mice the frequency of both mEPSCs and mIPSCs was reduced, indicating an overall impairment of excitatory and inhibitory inputs to CA3 pyramidal neurons. In treated Ts65Dn mice all these aberrant features were fully normalized, indicating that fluoxetine can rescue functional connectivity between the DG and CA3. The positive effects of fluoxetine on the DG-CA3 system suggest that early treatment with this drug could be a suitable therapy, possibly usable in humans, to restore the physiology of the hippocampal networks and, hence, memory functions.

CHF5074 restores visual memory ability and pre-synaptic cortical acetylcholine release in pre-plaque Tg2576 mice.

CHF5074, a new microglial modulator, attenuates memory deficit in Alzheimer's disease transgenic mice. In this study, the effect of an acute or subacute CHF5074 treatment on in vivo novel object recognition test and on [³H]Acetylcholine (ACh) and GABA release in pre-plaque (7-month-old) Tg2576 mice have been compared with those induced by the γ-secretase inhibitor LY450139 (semagacestat). Vehicle-treated Tg2576 mice displayed an impairment of recognition memory compared with wild-type animals. This impairment was recovered in transgenic animals acutely treated with CHF5074 (30 mg/kg), while LY450139 (1, 3, 10 mg/kg) was ineffective. In frontal cortex synaptosomes from vehicle-treated Tg2576 mice, K⁺-evoked [³H]ACh release was lower than that measured in wild-type mice. This reduction was absent in transgenic animals subacutely treated with CHF5074 (30 mg/kg daily for 8 days), while it was slightly, not significantly, amplified by LY450139 (3 mg/kg daily for 8 days). There were no differences between the groups on spontaneous [³H]ACh release as well as spontaneous and K⁺-evoked GABA release. These results suggest that CHF5074 has beneficial effects on visual memory and cortical cholinergic dysfunctions in pre-plaque Tg2576 mice. Together with previous findings, these data suggest that CHF5074 could be a possible candidate for early Alzheimer's disease therapeutic regimens.

Early pharmacotherapy with fluoxetine rescues dendritic pathology in the Ts65Dn mouse model of down syndrome.

Down syndrome DS is a genetic pathology characterized by brain hypotrophy and severe cognitive impairment. Although defective neurogenesis is an important determinant of mental disability, a severe dendritic pathology appears to be an equally important factor. A previous study showed that fluoxetine, a selective serotonin reuptake inhibitor, fully restores neurogenesis in the Ts65Dn mouse model of DS. The goal of the current study was to establish whether fluoxetine also restores dendritic development. In mice aged 45 days, treated with fluoxetine in the postnatal period P3-P15, we examined the dendritic arbor of the granule cells of the dentate gyrus (DG). The granule cells of trisomic mice had a severely hypotrophic dendritic arbor, fewer spines and a reduced innervation than euploid mice. Treatment with fluoxetine fully restored all these defects. In Ts65Dn mice, we found reduced levels of serotonin that were restored by treatment. Results show that a pharmacotherapy with fluoxetine is able to rescue not only the number of granule neurons but also their "quality" in terms of correct maturation and connectivity. These findings strongly suggest that fluoxetine may be a drug of choice for the improvement of the major defects in the DS brain and, possibly, of mental retardation.

Chemical phenotypes of P2X2 purinoreceptor immunoreactive cell bodies in the area postrema.

Purines such as adenosine 5'-triphosphate (ATP) act as extracellular messengers through specific purinergic receptors. Three different classes of purinergic receptors have been identified and termed P1, P2X, and P2Y. The purinergic receptor subunit P2X2 is a ligand-gated ion channel that is widely expressed by neurons in the CNS. In the brainstem medulla oblongata, the ionotropic P2X2 receptor (P2X2R) is enriched in the area postrema (AP). Two different antisera to P2X2R were used to determine the chemical nature of P2X2R immunoreactive cell bodies in the rat AP, an area lacking a blood-brain barrier. Subcellularly, P2X2R immunoreactivity was located to the periphery of individual cell bodies. The majority of P2X2R-immunoreactive cells were shown to contain tyrosine hydroxylase (TH) (63.5 ± 7.7%) and dopamine ß-hydroxylase (61.5 ± 5.1%). Phenylethanolamine N-methyltransferase (PNMT)-containing cells were not detected in the AP, supporting a noradrenergic nature of P2X2R cells in the AP. There were no P2X2R-immunoreactive cells in the AP that contained the GABA-synthesizing enzyme glutamic acid decarboxylase 65. Only single vesicular glutamate transporter 2-immunoreactive cell bodies that were not P2X2R-positive were demonstrated in the AP. Some P2X2R-positive cells in the AP were immunoreactive for the neuropeptides substance P and pituitary adenylate cyclase-activating polypeptide, whereas dynorphin-, enkephalin-, or cholecystokinin-positive cells were not P2X2R-immunoreactive. Presence of P2X2R in a majority of noradrenergic cells of the AP implies that ATP may have a regulatory action on neuronal noradrenaline release from the AP, a circumventricular organ with a strategic position enabling interactions between circulating substances and the central nervous system.

Parallel synthesis and cytotoxicity evaluation of a polyamine-quinone conjugates library.

A library of 24 derivatives designed by combining two natural products-derived fragments was prepared and tested to determine their anticancer potential in HT29 colon cancer cells. All library members inhibit cell proliferation as measured by MTT mitochondrial functional assay, with IC50 values in the 1-100 microM range. Entry 1b caused apoptotic EGFR-mediated intracellular signaling. Thus, polyamino-quinones emerged as readily accessible and easily diversified scaffolds for anticancer lead discovery.