Critical role of chemokine (C-C motif) receptor 2 (CCR2) in the KKAy + Apoe -/- mouse model of the metabolic syndrome

AIMS/HYPOTHESIS

Chemokines and their receptors such as chemokine (C-C motif) receptor 2 (CCR2) may contribute to the pathogenesis of the metabolic syndrome via their effects on inflammatory monocytes. Increased accumulation of CCR2-driven inflammatory monocytes in epididymal fat pads is thought to favour the development of insulin resistance. Ultimately, the resulting hyperglycaemia and dyslipidaemia contribute to development of the metabolic syndrome complications such as cardiovascular disease and diabetic nephropathy. Our goal was to elucidate the role of CCR2 and inflammatory monocytes in a mouse model that resembles the human metabolic syndrome.

METHODS

We generated a model of the metabolic syndrome by backcrossing KKAy ( + ) with Apoe ( -/- ) mice (KKAy ( + ) Apoe ( -/- )) and studied the role of CCR2 in this model system.

RESULTS

KKAy ( + ) Apoe ( -/- ) mice were characterised by the presence of obesity, insulin resistance, dyslipidaemia and increased systemic inflammation. This model also manifested two complications of the metabolic syndrome: atherosclerosis and diabetic nephropathy. Inactivation of Ccr2 in KKAy (+) Apoe ( -/- ) mice protected against the metabolic syndrome, as well as atherosclerosis and diabetic nephropathy. This protective phenotype was associated with a reduced number of inflammatory monocytes in the liver and muscle, but not in the epididymal fat pads; circulating levels of adipokines such as leptin, resistin and adiponectin were also not reduced. Interestingly, the proportion of inflammatory monocytes in the liver, pancreas and muscle, but not in the epididymal fat pads, correlated significantly with peripheral glucose levels.

CONCLUSIONS/INTERPRETATION

CCR2-driven inflammatory monocyte accumulation in the liver and muscle may be a critical pathogenic factor in the development of the metabolic syndrome.

Patent data mining: a tool for accelerating HIV vaccine innovation

Global access to advanced vaccine technologies is challenged by the interrelated components of intellectual property (IP) management strategies, technology transfer (legal and technical) capabilities and the capacity necessary for accelerating R&D, commercialization and delivery of vaccines. Due to a negative association with the management of IP, patents are often overlooked as a vast resource of freely available, information akin to scientific journals as well as business and technological information and trends fundamental for formulating policies and IP management strategies. Therefore, a fundamental step towards facilitating global vaccine access will be the assembly, organization and analysis of patent landscapes, to identify the amount of patenting, ownership (assignees) and fields of technology covered. This is critical for making informed decisions (e.g., identifying licensees, building research and product development collaborations, and ascertaining freedom to operate). Such information is of particular interest to the HIV vaccine community where the HIV Vaccine Enterprise, have voiced concern that IP rights (particularly patents and trade secrets) may prevent data and materials sharing, delaying progress in research and development of a HIV vaccine. We have compiled and analyzed a representative HIV vaccine patent landscape for a prime-boost, DNA/adenoviral vaccine platform, as an example for identifying obstacles, maximizing opportunities and making informed IP management strategy decisions towards the development and deployment of an efficacious HIV vaccine.

Abstract P1-03-06: Population Based In Vivo Biomarker Discovery Using Engineered Human Tumors

Background:

Tumors from patients exhibit significant inter-tumor variation, where each tumor harbors a unique set of genetic alterations that impact prognosis and response to treatment. Unfortunately, this variation contributes to low response rates in the clinic and creates significant challenges for treating patients with appropriate drugs. Cancer cell line based xenografts have traditionally been the preclinical model of choice to assess the efficacy of clinical compounds; however, such in vitro models exhibit inherent artifacts, and are unable to adequately capture natural variation seen in human tumor populations. It has therefore become a priority in oncology and personalized medicine to match patients to drugs that will result in a favorable treatment outcome. In this report, we describe a population based approach for response prediction featuring naturally occurring variation in tumors derived from genetically defined human-in-mouse models of cancer. Materials and Methods:

A population of De novo human breast tumors were generated by genetically engineering normal primary human breast epithelial cells with HER2 and SV40 early region (HER2/SV40er) or KRAS and SV40 early region (KRAS/SV40er) in an in vivo Human-In-Mouse (HIM) tissue transgenic model (Wu et al, Proc Natl Acad Sci U S A 2009, 106: 7022-2027). Each tumor of the population has been comprehensively characterized histopathologically, and at the RNA and DNA level. Furthermore, the population has been adapted to conduct quantitative efficacy studies of anti-cancer agents and combinations. Results:

The HER2/SV40er and the KRAS/SV40er HIM tumors develop as invasive human breast adenocarcinoma that are histologically similar to those observed in patients. Microarray and CGH profiling demonstrated significant inter-tumor variation among the established tumors, as has been reported for patient tumors. Moreover, the KRAS/SV40er tumors clustered with basal type breast cancers from patients, a poor prognosis human breast cancer subtype. Both HER2/SV40er and KRAS/SV40er tumors exhibited variable responses to treatments with the potent selective triple VEGFR inhibitor, tivozanib. Further characterization of those tumors, both pre-and post-treatment, identified potential biomarkers for tumor response to tivozanib. Discussion:

The genetically defined human-in-mouse tumors exhibited natural variations similar to that occurs in human cancer. This population-based HIM system enables us to identify and validate biomarkers of therapeutic response in an in vivo human tumor model. Figure available in online version.

The distribution of ribosomes between different functional states in livers of fed and starved mice

1. To investigate the role of ribosome function in regulating protein synthesis, the activity, distribution and functional states of ribosomal particles were investigated in livers of mice fed ad libitum or starved overnight. 2. The distribution of protein-synthesizing activity between polyribosomes of different sizes was analysed after incorporation of radioactive leucine, and the quantitative distribution of ribosomes as native subunits, monomers and polyribosomes was analysed after incorporation of orotic acid. Precursors labelled with (3)H or (14)C were given separately to fed and starved mice, so that livers from the two groups of animals were processed together. 3. The former experiments showed that starvation has little effect on the distribution of protein-synthesizing activity across polyribosome sedimentation patterns, though the latter experiments showed that the proportion of ribosomes existing as monomers increased from 9.5% to 15.2%, whereas the proportion existing as polyribosomes decreased from 81.4% to 75.6%. Starvation had a negligible effect on the proportion of native subunits, which accounted for 9.1% and 9.2% of the ribosomes in fed and starved mice respectively. 4. The monomeric ribosome fraction was isolated and subjected to ionic conditions which selectively dissociate single ribosomes. Starvation increased the proportion of monomers that dissociated from 59% to 72%, so the monomers that accumulate in livers of starved animals are single ribosomes and not monoribosomes resulting from degradation of polyribosomes. 5. The fate of newly formed ribosomal particles was studied by measuring the specific radioactivity of native subunits, monomers and polyribosomes at different times after injection of radioactively labelled orotic acid. Starvation did not appear to affect equilibration between newly formed particles and polyribosomes, and the radioactivity of polyribosomes in both groups of mice reached about 90% of that in native subunits after 4h. The radioactive labelling of monomers proceeded at a slower rate, especially after starvation. At 4h, the radioactivity of monomers was 64% and 55% that of native subunits in fed and starved mice respectively.

Sensory mapping in a congenitally deaf subject: MEG and fRMI studies of cross-modal non-plasticity

It has been proposed that the auditory cortex of deaf subjects may provide an example of cross-modal compensatory plasticity. We investigated whether sensory stimulation could elicit responses from auditory areas of a congenitally deaf subject. Neuromagnetic fields were recorded using a 37-channel biomagnetometer under conditions of: 1) visual stimulation; 2) somatosensory stimulation; and 3) a simple motor task. Visual items were reversing checkerboards and single light spots, presented in various portions of the visual field; somatosensory stimuli were pneumatic taps delivered to individual digit-segments and the lip; the motor task was self-paced finger tapping. In addition, functional magnetic resonance imaging was used to observe the activation elicited by full-field checkerboard and sign language stimuli. No responses to passively presented visual or somatosensory stimuli were observed in the auditory cortex. In contrast, somatosensory, motor, and visual cortices revealed evoked magnetic responses comparable to those from control subjects, indicating canonical anatomic and physiological organization in these areas. These data suggest that primary projection areas do not reveal obvious plastic effects. We suggest that in the human auditory cortex compensatory plasticity emerges primarily as a property of non-primary areas and is best observed under attentionally demanding conditions.

The impact of opioids, anticholinergic medications and disease progression on the prescription of laxatives in hospitalized palliative care patients: a retrospective analysis

Definitive risk factors for constipation in palliative care remain poorly defined. A retrospective analysis of 211 admissions to a palliative care unit was undertaken, with the main aim being to identify some factors, which influence laxative prescription. On univariate analysis, significant unadjusted associations were found between two or more prescribed laxatives and a diagnosis of malignancy, morphine equivalent dose, type of illness phase and the subsequent phase type, length of phase, anticholinergic load imposed by medications, symptom severity and functional status. Multiple ordinal logistic regressions revealed the prescription of one laxative to be significantly associated with oral morphine-equivalent dose, total anticholinergic load (odds ratio [OR] 1.4, 95% CI = 1.0-2.0), disease progression to terminal phase and death (OR 0.1, 95% CI = 0.0-0.3), and length of phase (OR 1.1, 95% CI = 1.0-1.2). Similar results were obtained for the prescription of two or more laxatives. Two additional measures of function, toileting (OR 3.6, 95% CI = 1.6-8.2) and transfer (OR 0.4 95% CI = 0.2-0.9), also became significant. Total anticholinergic load was significantly associated with the prescription of a single laxative (OR 1.4, 95% CI = 1.0-2.0) and two or more laxatives (OR 1.8, 95% CI = 1.3-2.5) for each unit increase in anticholinergic load. Opioids and in particular opioids prescribed at higher doses, the total anticholinergic load associated with prescribed medications, the degree of impaired physical function of a person, their length of stay in a palliative care unit and their proximity to death were all strongly related to the prescription of laxatives.

Superconductivity in just four pairs of (BETS)2GaCl4 molecules

How small can a sample of superconducting material be and still display superconductivity? This question is relevant to our fundamental understanding of superconductivity, and also to applications in nanoscale electronics, because Joule heating of interconnecting wires is a major problem in nanoscale devices. It has been shown that ultrathin layers of metal can display superconductivity, but any limits on the size of superconducting systems remain a mystery. (BETS)2GaCl4, where BETS is bis(ethylenedithio)tetraselenafulvalene, is an organic superconductor, and in bulk it has a superconducting transition temperature Tc of approximately 8 K and a two-dimensional layered structure that is reminiscent of the high-Tc cuprate superconductors. Here, we use scanning tunnelling spectroscopy to show that a single layer of (BETS)2GaCl4 molecules on an Ag(111) surface displays a superconducting gap that increases exponentially with the length of the molecular chain. Moreover, we show that a superconducting gap can still be detected for just four pairs of (BETS)2GaCl4 molecules. Real-space spectroscopic images directly visualize the chains of BETS molecules as the origin of the superconductivity.