Characterization of human immunodeficiency virus type 1 mutantswith decreased sensitivity to proteinase inhibitor Ro 31-8959

AbstractA human immunodeficiency virus type 1 (HIV-1) variant with highly reduced susceptibility to Ro 31-8959, an inhibitor of the viral proteinase, has been selected by repeated passage of wild-type virus in CEM cells in the presence of increasing concentrations of the inhibitor. Peptide sequences of the proteinase of selected virus were obtained from proviral DNA. Sequence comparison to wild-type (wt) proteinase demonstrated two amino acid substitutions in the resistant virus, a Gly to Val exchange at position 48 and a Leu to Met exchange at position 90. Furthermore, sequences of intermediate passage virus suggest contributions from positions 12, 36, 57, and 63 in early steps of resistance development. The selected virus showed a ca. 40-fold increase in 50% inhibitory concentration of Ro 31-8959. Growth kinetics of resistant virus were comparable to wild-type virus and the resistant genotype proved to be stable in the absence of inhibitor. Directed mutagenesis of the HIV-1 HXB2 proteinase at positions 48 and 90 suggested that each mutation alone led to a moderate decrease in sensitivity of the recombinant virus to proteinase inhibitor. However, a recombinant virus carrying both mutations in the proteinase gene showed a significant reduction in its sensitivity to Ro 31-8959 thus proving the importance of these exchanges for the resistance phenotype

Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study

Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation

Symmetry is Not a Universal Law of Beauty

Scientific disciplines as diverse as biology, physics, and psychological aesthetics regard symmetry as one of the most important principles in nature and one of the most powerful determinants of beauty. However, symmetry has a low standing in the arts and humanities. This difference in the valuation of symmetry is a remarkable illustration of the gap between the two cultures. To close this gap, we conducted an interdisciplinary, empirical study to directly demonstrate the effects of art expertise on symmetry appreciation. Two groups of art experts—artists and art historians—and a group of non-experts provided spontaneous beauty ratings of visual stimuli that varied in symmetry and complexity. In complete contrast to responses typically found in non-art experts, art experts found asymmetrical and simple stimuli as most beautiful. This is evidence of the effects of specific education and training on aesthetic appreciation and a direct challenge to the universality of symmetry

Experiencing Beauty in Everyday Life

Beauty surrounds us in many ways every day. In 3 experience sampling (ESM) studies we investigated frequency, category of eliciting stimuli (natural vs human-made) and, the potential moderating role of several individual difference measures of such everyday experiences of beauty in an ecologically valid manner. Further, we explored the impact of such experiences on valence & arousal. Study 1 re-analysed data from a previous study, in line with the current aims. In Studies 2 and 3, we asked participants to report daily experiences of beauty using a mixed random and event-contingent sampling schedule. Mobile notifications (random sampling) prompted participants to take a photo and rate the beauty of their surroundings. Further, current valence and arousal were assessed. Notification frequency and total days of participation differed between these two studies. Participants were able to report additional experiences outside of the notification windows (event-contingent sampling). Our results indicate that we frequently encounter beauty in everyday life and that we find it in nature, in particular. Our results further suggest a mood-boosting effect of encounters with beauty. Lastly, our results indicate influences of individual differences however, these were inconclusive and require further attention

Genetic engineering of cell lines using lentiviral vectors to achieve antibody secretion following encapsulated implantation

The controlled delivery of antibodies by immunoisolated bioimplants containing genetically engineered cells is an attractive and safe approach for chronic treatments. To reach therapeutic antibody levels there is a need to generate renewable cell lines, which can long-term survive in macroencapsulation devices while maintaining high antibody specific productivity. Here we have developed a dual lentiviral vector strategy for the genetic engineering of cell lines compatible with macroencapsulation, using separate vectors encoding IgG light and heavy chains. We show that IgG expression level can be maximized as a function of vector dose and transgene ratio. This approach allows for the generation of stable populations of IgG-expressing C2C12 mouse myoblasts, and for the subsequent isolation of clones stably secreting high IgG levels. Moreover, we demonstrate that cell transduction using this lentiviral system leads to the production of a functional glycosylated antibody by myogenic cells. Subsequent implantation of antibody-secreting cells in a high-capacity macroencapsulation device enables continuous delivery of recombinant antibodies in the mouse subcutaneous tissue, leading to substantial levels of therapeutic IgG detectable in the plasma. (C) 2013 Elsevier Ltd. All rights reserved

A subcutaneous cellular implant for passive immunization against amyloid-β reduces brain amyloid and tau pathologies

Passive immunization against toxic misfolded proteins could offer protection against neurodegenerative disease. Lathuilière et al . report the development of a retrievable device to encapsulate cells secreting recombinant anti-amyloid-β antibodies. When implanted in mouse models of Alzheimer's disease, the system delivers antibodies to the brain and reduces amyloid and tau pathologies

A subcutaneous cellular implant for passive immunization against amyloid-beta reduces brain amyloid and tau pathologies

Passive immunization against toxic misfolded proteins could offer protection against neurodegenerative disease. LathuiliSre et al. report the development of a retrievable device to encapsulate cells secreting recombinant anti-amyloid-beta antibodies. When implanted in mouse models of Alzheimer's disease, the system delivers antibodies to the brain and reduces amyloid and tau pathologies.Passive immunization against toxic misfolded proteins could offer protection against neurodegenerative disease. LathuiliSre et al. report the development of a retrievable device to encapsulate cells secreting recombinant anti-amyloid-beta antibodies. When implanted in mouse models of Alzheimer's disease, the system delivers antibodies to the brain and reduces amyloid and tau pathologies.Passive immunization against misfolded toxic proteins is a promising approach to treat neurodegenerative disorders. For effective immunotherapy against Alzheimer's disease, recent clinical data indicate that monoclonal antibodies directed against the amyloid-beta peptide should be administered before the onset of symptoms associated with irreversible brain damage. It is therefore critical to develop technologies for continuous antibody delivery applicable to disease prevention. Here, we addressed this question using a bioactive cellular implant to deliver recombinant anti-amyloid-beta antibodies in the subcutaneous tissue. An encapsulating device permeable to macromolecules supports the long-term survival of myogenic cells over more than 10 months in immunocompetent allogeneic recipients. The encapsulated cells are genetically engineered to secrete high levels of anti-amyloid-beta antibodies. Peripheral implantation leads to continuous antibody delivery to reach plasma levels that exceed 50 A mu g/ml. In a proof-of-concept study, we show that the recombinant antibodies produced by this system penetrate the brain and bind amyloid plaques in two mouse models of the Alzheimer's pathology. When encapsulated cells are implanted before the onset of amyloid plaque deposition in TauPS2APP mice, chronic exposure to anti-amyloid-beta antibodies dramatically reduces amyloid-beta(40) and amyloid-beta(42) levels in the brain, decreases amyloid plaque burden, and most notably, prevents phospho-tau pathology in the hippocampus. These results support the use of encapsulated cell implants for passive immunotherapy against the misfolded proteins, which accumulate in Alzheimer's disease and other neurodegenerative disorders