JC Polyomavirus Uses Extracellular Vesicles To Infect Target Cells

The endemic human JC polyomavirus (JCPyV) causes progressive multifocal leukoencephalopathy in immune-suppressed patients. The mechanisms of virus infection in vivo are not understood because the major target cells for virus in the brain do not express virus receptors and do not bind virus. We found that JCPyV associates with extracellular vesicles (EVs) and can infect target cells independently of virus receptors. Virus particles were found packaged inside extracellular vesicles and attached to the outer side of vesicles. Anti-JCPyV antisera reduced infection by purified virus but had no effect on infection by EV-associated virus. Treatment of cells with the receptor-destroying enzyme neuraminidase inhibited infection with purified virus but did not inhibit infection by EV-associated virus. Mutant pseudoviruses defective in sialic acid receptor binding could not transduce cells as purified pseudovirions but could do so when associated with EVs. This alternative mechanism of infection likely plays a critical role in the dissemination and spread of JCPyV both to and within the central nervous system

Biogenesis of JC Polyomavirus Associated Extracellular Vesicles

JC polyomavirus (JCPyV) is a small, non-enveloped virus that persists in the kidney in about half the adult population. In severely immune-compromised individuals JCPyV causes the neurodegenerative disease progressive multifocal leukoencephalopathy (PML) in the brain. JCPyV has been shown to infect cells by both direct and indirect mechanisms, the latter involving extracellular vesicle (EV) mediated infection. While direct mechanisms of infection are well studied indirect EV mediated mechanisms are poorly understood. Using a combination of chemical and genetic approaches we show that several overlapping intracellular pathways are responsible for the biogenesis of virus containing EV. Here we show that targeting neutral sphingomyelinase 2 (nSMase2) with the drug cambinol decreased the spread of JCPyV over several viral life cycles. Genetic depletion of nSMase2 by either shRNA or CRISPR/Cas9 reduced EV-mediated infection. Individual knockdown of seven ESCRT-related proteins including HGS, ALIX, TSG101, VPS25, VPS20, CHMP4A, and VPS4A did not significantly reduce JCPyV associated EV (JCPyV(+) EV) infectivity, whereas knockdown of the tetraspanins CD9 and CD81 or trafficking and/or secretory autophagy-related proteins RAB8A, RAB27A, and GRASP65 all significantly reduced the spread of JCPyV and decreased EV-mediated infection. These findings point to a role for exosomes and secretory autophagosomes in the biogenesis of JCPyV associated EVs with specific roles for nSMase2, CD9, CD81, RAB8A, RAB27A, and GRASP65 proteins

A framework for human microbiome research

A variety of microbial communities and their genes (the microbiome) exist throughout the human body, with fundamental roles in human health and disease. The National Institutes of Health (NIH)-funded Human Microbiome Project Consortium has established a population-scale framework to develop metagenomic protocols, resulting in a broad range of quality-controlled resources and data including standardized methods for creating, processing and interpreting distinct types of high-throughput metagenomic data available to the scientific community. Here we present resources from a population of 242 healthy adults sampled at 15 or 18 body sites up to three times, which have generated 5,177 microbial taxonomic profiles from 16S ribosomal RNA genes and over 3.5 terabases of metagenomic sequence so far. In parallel, approximately 800 reference strains isolated from the human body have been sequenced. Collectively, these data represent the largest resource describing the abundance and variety of the human microbiome, while providing a framework for current and future studies

Structure, function and diversity of the healthy human microbiome

Author Posting. © The Authors, 2012. This article is posted here by permission of Nature Publishing Group. The definitive version was published in Nature 486 (2012): 207-214, doi:10.1038/nature11234.Studies of the human microbiome have revealed that even healthy individuals differ remarkably in the microbes that occupy habitats such as the gut, skin and vagina. Much of this diversity remains unexplained, although diet, environment, host genetics and early microbial exposure have all been implicated. Accordingly, to characterize the ecology of human-associated microbial communities, the Human Microbiome Project has analysed the largest cohort and set of distinct, clinically relevant body habitats so far. We found the diversity and abundance of each habitat’s signature microbes to vary widely even among healthy subjects, with strong niche specialization both within and among individuals. The project encountered an estimated 81–99% of the genera, enzyme families and community configurations occupied by the healthy Western microbiome. Metagenomic carriage of metabolic pathways was stable among individuals despite variation in community structure, and ethnic/racial background proved to be one of the strongest associations of both pathways and microbes with clinical metadata. These results thus delineate the range of structural and functional configurations normal in the microbial communities of a healthy population, enabling future characterization of the epidemiology, ecology and translational applications of the human microbiome.This research was supported in part by National Institutes of Health grants U54HG004969 to B.W.B.; U54HG003273 to R.A.G.; U54HG004973 to R.A.G., S.K.H. and J.F.P.; U54HG003067 to E.S.Lander; U54AI084844 to K.E.N.; N01AI30071 to R.L.Strausberg; U54HG004968 to G.M.W.; U01HG004866 to O.R.W.; U54HG003079 to R.K.W.; R01HG005969 to C.H.; R01HG004872 to R.K.; R01HG004885 to M.P.; R01HG005975 to P.D.S.; R01HG004908 to Y.Y.; R01HG004900 to M.K.Cho and P. Sankar; R01HG005171 to D.E.H.; R01HG004853 to A.L.M.; R01HG004856 to R.R.; R01HG004877 to R.R.S. and R.F.; R01HG005172 to P. Spicer.; R01HG004857 to M.P.; R01HG004906 to T.M.S.; R21HG005811 to E.A.V.; M.J.B. was supported by UH2AR057506; G.A.B. was supported by UH2AI083263 and UH3AI083263 (G.A.B., C. N. Cornelissen, L. K. Eaves and J. F. Strauss); S.M.H. was supported by UH3DK083993 (V. B. Young, E. B. Chang, F. Meyer, T. M. S., M. L. Sogin, J. M. Tiedje); K.P.R. was supported by UH2DK083990 (J. V.); J.A.S. and H.H.K. were supported by UH2AR057504 and UH3AR057504 (J.A.S.); DP2OD001500 to K.M.A.; N01HG62088 to the Coriell Institute for Medical Research; U01DE016937 to F.E.D.; S.K.H. was supported by RC1DE0202098 and R01DE021574 (S.K.H. and H. Li); J.I. was supported by R21CA139193 (J.I. and D. S. Michaud); K.P.L. was supported by P30DE020751 (D. J. Smith); Army Research Office grant W911NF-11-1-0473 to C.H.; National Science Foundation grants NSF DBI-1053486 to C.H. and NSF IIS-0812111 to M.P.; The Office of Science of the US Department of Energy under Contract No. DE-AC02-05CH11231 for P.S. C.; LANL Laboratory-Directed Research and Development grant 20100034DR and the US Defense Threat Reduction Agency grants B104153I and B084531I to P.S.C.; Research Foundation - Flanders (FWO) grant to K.F. and J.Raes; R.K. is an HHMI Early Career Scientist; Gordon&BettyMoore Foundation funding and institutional funding fromthe J. David Gladstone Institutes to K.S.P.; A.M.S. was supported by fellowships provided by the Rackham Graduate School and the NIH Molecular Mechanisms in Microbial Pathogenesis Training Grant T32AI007528; a Crohn’s and Colitis Foundation of Canada Grant in Aid of Research to E.A.V.; 2010 IBM Faculty Award to K.C.W.; analysis of the HMPdata was performed using National Energy Research Scientific Computing resources, the BluBioU Computational Resource at Rice University

The Association between Self-Reported Energy Intake and Intra-Abdominal Adipose Tissue in Perimenopausal Women

We have previously shown that physical activity predicts intra-abdominal adipose tissue (IAT), but it is unknown whether energy intake predicts IAT independently of physical activity in a community-based, naturalistic environment. The association of energy intake with IAT was explored cross-sectionally in women, recruited between 2002 and 2005 for a study of fat patterning in midlife. IAT at L4-L5 vertebral interspace was assessed by computed tomography, energy intake by the Block Food Frequency Questionnaire, and physical activity by the Kaiser Physical Activity Survey. Linear regression models were used for the principal analyses. Among the 257 women, 48% were African American and 52% were Caucasian. Women were 52±3 years old, and 49% were postmenopausal. Every 500 kcal increase in energy intake was associated with a 6% higher IAT (P=0.02), independent of physical activity (P=0.02), after adjustment for ethnicity, menopausal status, age, smoking, income, and DXA-assessed percent body fat. Energy intake had a significant interaction with ethnicity (P=0.02), but not with physical activity. Models using the IAT to subcutaneous abdominal adipose tissue ratio as an outcome had similar associations. In conclusion, self-reported EI was associated with preferential IAT accumulation in midlife women, independent of physical activity. This association was significantly stronger in Caucasian than African American women. Future longitudinal studies are needed to explore lifestyle predictors of IAT accumulation during the menopausal transition

JC Polyomavirus Uses Extracellular Vesicles To Infect Target Cells

JC polyomavirus (JCPyV) is a ubiquitous human pathogen that causes progressive multifocal leukoencephalopathy (PML), a severe and often fatal neurodegenerative disease in immunocompromised or immunomodulated patients. The mechanisms responsible for initiating infection in susceptible cells are not completely known. The major attachment receptor for the virus, lactoseries tetrasaccharide c (LSTc), is paradoxically not expressed on oligodendrocytes or astrocytes in human brain, and virus does not bind to these cells. Because these are the major cell types targeted by the virus in the brain, we hypothesized that alternative mechanisms of infection must be responsible. Here we provide evidence that JCPyV is packaged in extracellular vesicles from infected cells. Infection of target cells by vesicle-associated virus is not dependent on LSTc and is not neutralized by antisera directed against the virus. This is the first demonstration of a polyomavirus using extracellular vesicles as a means of transmission.The endemic human JC polyomavirus (JCPyV) causes progressive multifocal leukoencephalopathy in immune-suppressed patients. The mechanisms of virus infection in vivo are not understood because the major target cells for virus in the brain do not express virus receptors and do not bind virus. We found that JCPyV associates with extracellular vesicles (EVs) and can infect target cells independently of virus receptors. Virus particles were found packaged inside extracellular vesicles and attached to the outer side of vesicles. Anti-JCPyV antisera reduced infection by purified virus but had no effect on infection by EV-associated virus. Treatment of cells with the receptor-destroying enzyme neuraminidase inhibited infection with purified virus but did not inhibit infection by EV-associated virus. Mutant pseudoviruses defective in sialic acid receptor binding could not transduce cells as purified pseudovirions but could do so when associated with EVs. This alternative mechanism of infection likely plays a critical role in the dissemination and spread of JCPyV both to and within the central nervous system

Contribution of common chronic conditions to midlife physical function decline: The Study of Women’s Health Across the Nation

Abstract Background Chronic conditions are associated with worse physical function and commonly develop during midlife. We tested whether the presence of 8 chronic conditions, or the development of these conditions, is associated with declines in physical function among midlife women as they transition into early late life. Methods Participants (N = 2283) were from the Study of Women’s Health Across the Nation. Physical function was assessed at 8 visits starting at the study’s fourth clinic visit in 2000/2001 through follow-up visit 15 (2015/2017) using the Short Form-36 Physical Function subscale. Chronic conditions included diabetes, hypertension, osteoarthritis, osteoporosis, stroke, heart disease, cancer, and depressive symptoms. Repeated-measures Poisson regression modeled associations between 1) prevalent chronic conditions at analytic baseline (visit 4) and longitudinal physical function, and 2) change in physical function associated with developing a new condition. Models were adjusted with the total number of other chronic conditions at visit 4. Results In separate fully-adjusted longitudinal models, prevalent heart disease and osteoporosis were associated with 18% (IRR = 0.815, 95% confidence interval [CI]: 0.755–0.876) and 12% (IRR = 0.876, 95% CI: 0.825–0.927) worse initial physical function, respectively. Prevalent osteoarthritis was associated with approximately 6% (IRR = 0.936, 95% CI: 0.913–0.958) worse initial physical function, and a slight additional worsening over time (IRR = 0.995, 95% CI: 0.994–0.996). A 12% (IRR = 0.878, 95% CI: 0.813–0.950) decrease in physical function concurrent with stroke development was evident, as was accelerated decline in physical function concurrent with heart disease development (IRR = 0.991, 95% CI: 0.988–0.995). Conclusions Initial prevalent conditions related to the musculoskeletal system were associated with worse initial physical function, with some evidence of accelerated decline in physical function with osteoarthritis. Stroke and heart disease are less common than osteoarthritis in this age group, but the severe effects of these conditions on physical function shows the need for a greater focus on cardiovascular health during midlife. Women who develop chronic conditions during midlife may be at particular risk for poor physical function as they age, warranting disability prevention efforts focused on this population.http://deepblue.lib.umich.edu/bitstream/2027.42/174022/1/40695_2020_Article_53.pd

Factors associated with developing vaginal dryness symptoms in women transitioning through menopause

ObjectiveTo evaluate factors associated with incident self-reported vaginal dryness and the consequences of this symptom across the menopausal transition in a multiracial/ethnic cohort of community-dwelling women.MethodsWe analyzed questionnaire and biomarker data from baseline and 13 approximately annual visits over 17 years (1996-2013) from 2,435 participants in the Study of Women's Health Across the Nation, a prospective cohort study. We used discrete-time Cox proportional-hazards regression to identify predictors of incident vaginal dryness and to evaluate vaginal dryness as a predictor of pain during intercourse and changes in sexual intercourse frequency.ResultsThe prevalence of vaginal dryness increased from 19.4% among all women at baseline (ages 42-53 years) to 34.0% at the 13th visit (ages 57-69 years). Advancing menopausal stage, surgical menopause, anxiety, and being married were positively associated with developing vaginal dryness, regardless of partnered sexual activity. For women not using hormone therapy, higher concurrent levels of endogenous estradiol were inversely associated (multivariable-adjusted hazard ratio: 0.94 per 0.5 standard deviation increase, 95% confidence interval: 0.91-0.98). Concurrent testosterone levels, concurrent dehydroepiandrosterone sulfate levels, and longitudinal change in any reproductive hormone were not associated with developing vaginal dryness. Both vaginal dryness and lubricant use were associated with subsequent reporting of pain during intercourse, but not with a decline in intercourse frequency.ConclusionIn these longitudinal analyses, our data support many clinical observations about the relationship between vaginal dryness, menopause, and pain during intercourse, and suggest that reporting of vaginal dryness is not related to androgen level or sexual intercourse frequency

Patterns of Sexual Activity and the Development of Sexual Pain Across the Menopausal Transition

ObjectiveTo examine whether patterns of sexual intercourse frequency and demographic, menopausal status, genitourinary, health, and psychosocial factors are associated with developing sexual pain across the menopausal transition.MethodsThese were longitudinal analyses of questionnaire data from the multicenter, multiracial and ethnic prospective cohort SWAN (Study of Women's Health Across the Nation) (1995-2008). We used multivariable discrete-time proportional hazards models to examine whether incident sexual pain was associated with preceding long-term (up to 10 visits) or short-term (two and three visits) sexual intercourse frequency patterns or other factors (eg, menopause status, genitourinary symptoms, lifestyle factors, and mental health).ResultsOf the 2,247 women with no sexual pain at baseline, 1,087 (48.4%) developed sexual pain at least "sometimes" up to 10 follow-up visits over 13 years. We found no consistent association between prior patterns of sexual intercourse frequency and development of sexual pain. For example, neither decreases in intercourse frequency from baseline (adjusted hazard ratio [aHR] 0.93, 95% CI 0.73-1.19) nor decreases in frequency over three prior visits (aHR 1.00, 95% CI 0.72-1.41) were associated with incident pain. Reasons for interruptions in intercourse activity at the prior visit, including lack of interest (aHR 1.64, 95% CI 0.74-3.65) and relationship issues (aHR 0.36, 95% CI 0.04-2.88), were not associated with developing pain. Being postmenopausal using hormone therapy (aHR 3.16, 95% CI 1.46-6.85), and reported vaginal dryness (aHR 3.73, 95% CI 2.88-4.83) were most strongly associated with incident sexual pain.ConclusionLong-term and short-term declines in sexual intercourse frequency across the menopausal transition were not associated with increased hazard of developing pain with intercourse. This empirical evidence does not support the common belief that a reduction in women's sexual frequency is responsible for their symptoms of sexual pain