Novel antagonist antibody to TLR3 blocks poly(I:C)-induced inflammation in vivo and in vitro

Toll-like receptor 3 (TLR3) binds and signals in response to dsRNA and poly(I:C), a synthetic double stranded RNA analog. Activation of TLR3 triggers innate responses that may play a protective or detrimental role in viral infections or in immune-mediated inflammatory diseases through amplification of inflammation. Two monoclonal antibodies, CNTO4685 (rat anti-mouse TLR3) and CNTO5429 (CDRs from CNTO4685 grafted onto a mouse IgG1 scaffold) were generated and characterized. These mAbs bind the extracellular domain of mouse TLR3, inhibit poly(I:C)-induced activation of HEK293T cells transfected with mTLR3, and reduce poly(I:C)-induced production of CCL2 and CXCL10 by primary mouse embryonic fibroblasts. CNTO5429 decreased serum IL-6 and TNFα levels post-intraperitoneal poly(I:C) administration, demonstrating in vivo activity. In summary, specific anti-mTLR3 mAbs have been generated to assess TLR3 antagonism in mouse models of inflammation.     

Expression of estrogen and progesterone receptors and estrogen metabolizing enzymes in different breast cancer cell lines

Prolonged exposure to estrogens is a significant risk factor for the development of breast cancer. Estrogens exert carcinogenic effects by stimulating cell proliferation or through oxidative metabolism that forms DNA-damaging species. In the present study, we aimed to provide a better understanding of estrogen metabolism and actions in breast cancer, and to characterize model breast cancer cell lines. We determined the expression profiles of the genes for the estrogen and progesterone receptors, and for 18 estrogen-metabolizing enzymes in eight cell lines: MCF-7, MCF-10A, T47D, SKBR3, MDA-MB-231, MDA-MB-361, Hs-578T and Hs-578Bst cells. Similar gene expression profiles of these receptors and enzymes for the formation of estradiol via the aromatase and sulfatase pathways were observed in the MCF-7 and T47D metastatic cell lines. The MDA-MB-361 cells expressed ESR1, ESR2 and PGR as well, but differed in expression of the estrogen-metabolizing enzymes. In the MDA-MB-231 and SKBR3 cells, all of these estrogen-forming enzymes were expressed, although the lack of ESR1 and the low levels of ESR2 expression suggested that the estrogens can only act via non-ER mediated pathways. In the non-tumorigenic MCF-10A cell line, the key enzymes of the aromatase pathway were not expressed, and the sulfatase pathway also had a marginal role. The comparison between gene expression profiles of the non-tumorigenic Hs-578Bst cells and the cancerous Hs-578T cells revealed that they can both form estrogens via the sulfatase pathway, while the aromatase pathway is less important in the Hs-578Bst cells. The Hs-578T cells showed low levels of ESR1, ESR2 and PGR expression, while only ESR1 and ESR2 expression was detected in the Hs-578Bst cells. Our data show that the cell lines examined provide the full range of model systems and should further be compared with the expression profiles of breast cancer specimens.     

Recent Advances in Vanadium‐Based Aqueous Rechargeable Zinc‐Ion Batteries

Aqueous zinc‐ion batteries (AZIBs) have attracted considerable attention as promising next‐generation power sources because of the abundance, low cost, eco‐friendliness, and high security of Zn resources. Recently, vanadium‐based materials as cathodes in AZIBs have gained interest owing to their rich electrochemical interaction with Zn²⁺ and high theoretical capacity. However, existing AZIBs are still far from meeting commercial requirements. This article summarizes recent advances in the rational design of vanadium‐based materials toward AZIBs. In particular, it highlights various tactics that have been reported to increase the intercalation space, structural stability, and the diffusion ability of the guest Zn²⁺, as well as explores the structure‐dependent electrochemical performance and the corresponding energy storage mechanism. Furthermore, this article summarizes recent achievements in the optimization of aqueous electrolytes and Zn anodes to resolve the issues that remain with Zn anodes, including dendrite formation, passivation, corrosion, and the low coulombic efficiency of plating/stripping. The rationalization of these research findings can guide further investigations in the design of cathode/anode materials and electrolytes for next‐generation AZIBs.     

Actin stress fibre subtypes in mesenchymal-migrating cells

Mesenchymal cell migration is important for embryogenesis and tissue regeneration. In addition, it has been implicated in pathological conditions such as the dissemination of cancer cells. A characteristic of mesenchymal-migrating cells is the presence of actin stress fibres, which are thought to mediate myosin II-based contractility in close cooperation with associated focal adhesions. Myosin II-based contractility regulates various cellular activities, which occur in a spatial and temporal manner to achieve directional cell migration. These myosin II-based activities involve the maturation of integrin-based adhesions, generation of traction forces, establishment of the front-to-back polarity axis, retraction of the trailing edge, extracellular matrix remodelling and mechanotransduction. Growing evidence suggests that actin stress fibre subtypes, namely dorsal stress fibres, transverse arcs and ventral stress fibres, could provide this spatial and temporal myosin II-based activity. Consistent with their functional differences, recent studies have demonstrated that the molecular composition of actin stress fibre subtypes differ significantly. This present review focuses on the current view of the molecular composition of actin stress fibre subtypes and how these fibre subtypes regulate mesenchymal cell migration.     

Vitamin D Status,Filaggrin Genotype,and Cardiovascular Risk Factors: A Mendelian Randomization Approach

Background

Vitamin D deficiency is associated with increased cardiovascular disease risk in observational studies. Whether these associations are causal is not clear. Loss-of-function mutations in the filaggrin gene result in up to 10% higher serum vitamin D concentrations, supposedly due to a decreased UV-protection of the keratinocytes. We used a Mendelian randomization approach to estimate the causal effect of vitamin D status on serum lipids, blood pressure, body mass index, waist circumference, and the metabolic syndrome.

Methods

Three population based studies were included, Monica10 (2,656 individuals aged 40–71 years), Inter99 (6,784 individuals aged 30–60 years), and Health2006 (3,471 individuals aged 18–69 years) conducted in 1993–94, 1999–2001, and 2006–2008, respectively. Participants were genotyped for the two most common filaggrin gene mutations in European descendants R501X and 2282del4, in all three studies and further for the R2447X mutation in the Inter99 and Health2006 studies. Filaggrin genotype was used as instrumental variable for vitamin D status. Baseline measurements of serum 25-hydroxyvitamin D were performed in all three studies.

Results

Instrumental variable analyses showed a 23.8% (95% confidence interval, CI 3.0, 48.6) higher HDL cholesterol level and a 30.5% (95% CI: 0.8, 51.3) lower serum level of triglycerides per doubling of vitamin D. These associations were, however, not statistically significant when applying the Bonferroni adjusted significance level. The remaining lipids showed non-significant changes in a favorable direction. Doubling of vitamin D gave a non-significantly lower odds ratio = 0.26 (95% CI: 0.06, 1.17) of the metabolic syndrome. There were no statistically significant causal effects of vitamin D status on blood pressure, body mass index, or waist circumference.

Conclusion

Our results support a causal effect of higher vitamin D status on a more favorable lipid profile, although more studies in other populations are needed to confirm our results.     

Cannabinoid Receptor CB2 Modulates Axon Guidance

Navigation of retinal projections towards their targets is regulated by guidance molecules and growth cone transduction mechanisms. Here, we present in vitro and in vivo evidences that the cannabinoid receptor 2 (CB₂R) is expressed along the retino-thalamic pathway and exerts a modulatory action on axon guidance. These effects are specific to CB₂R since no changes were observed in mice where the gene coding for this receptor was altered (cnr2 ^−/−). The CB₂R induced morphological changes observed at the growth cone are PKA dependent and require the presence of the netrin-1 receptor, Deleted in Colorectal Cancer. Interfering with endogenous CB₂R signalling using pharmacological agents increased retinal axon length and induced aberrant projections. Additionally, cnr2 ^−/− mice showed abnormal eye-specific segregation of retinal projections in the dorsal lateral geniculate nucleus (dLGN) indicating CB₂R’s implication in retinothalamic development. Overall, this study demonstrates that the contribution of endocannabinoids to brain development is not solely mediated by CB₁R, but also involves CB₂R.     

Accounting for environmental variation in co‐occurrence modelling reveals the importance of positive interactions in root‐associated fungal communities

Understanding the role of interspecific interactions in shaping ecological communities is one of the central goals in community ecology. In fungal communities, measuring interspecific interactions directly is challenging because these communities are composed of large numbers of species, many of which are unculturable. An indirect way of assessing the role of interspecific interactions in determining community structure is to identify the species co‐occurrences that are not constrained by environmental conditions. In this study, we investigated co‐occurrences among root‐associated fungi, asking whether fungi co‐occur more or less strongly than expected based on the environmental conditions and the host plant species examined. We generated molecular data on root‐associated fungi of five plant species evenly sampled along an elevational gradient at a high arctic site. We analysed the data using a joint species distribution modelling approach that allowed us to identify those co‐occurrences that could be explained by the environmental conditions and the host plant species, as well as those co‐occurrences that remained unexplained and thus more probably reflect interactive associations. Our results indicate that not only negative but also positive interactions play an important role in shaping microbial communities in arctic plant roots. In particular, we found that mycorrhizal fungi are especially prone to positively co‐occur with other fungal species. Our results bring new understanding to the structure of arctic interaction networks by suggesting that interactions among root‐associated fungi are predominantly positive.     

Higher host plant specialization of root‐associated endophytes than mycorrhizal fungi along an arctic elevational gradient

How community‐level specialization differs among groups of organisms, and changes along environmental gradients, is fundamental to understanding the mechanisms influencing ecological communities. In this paper, we investigate the specialization of root‐associated fungi for plant species, asking whether the level of specialization varies with elevation. For this, we applied DNA barcoding based on the ITS region to root samples of five plant species equivalently sampled along an elevational gradient at a high arctic site. To assess whether the level of specialization changed with elevation and whether the observed patterns varied between mycorrhizal and endophytic fungi, we applied a joint species distribution modeling approach. Our results show that host plant specialization is not environmentally constrained in arctic root‐associated fungal communities, since there was no evidence for changing specialization with elevation, even if the composition of root‐associated fungal communities changed substantially. However, the level of specialization for particular plant species differed among fungal groups, root‐associated endophytic fungal communities being highly specialized on particular host species, and mycorrhizal fungi showing almost no signs of specialization. Our results suggest that plant identity affects associated mycorrhizal and endophytic fungi differently, highlighting the need of considering both endophytic and mycorrhizal fungi when studying specialization in root‐associated fungal communities.     

The role of omega6 to omega3 ratio in development and progression of age-related macular degeneration

The aim of this study is to investigate possible connection between omega-6/omega-3 fatty acid ratio and development and progression of Age-Related Macular Degeneration (ARMD). We examined 125 patients diagnosed with ARMD and divided into 5 groups of 25 patients according to CARMS (Clinical Age-Related Maculopathy Staging System). Control group consists of 51 patients with similar ages, without ARMD. All of them underwent stereobiomicroscopy, fundus photography and fluorescein angiography. Dietary fatty acids intake was measured using food frequency questionnaire (FFQ). The FFQ was based on previously validated questionnaire (DIETQ, Tinuviel Software, Warington, Ches, UK) and FFQ2 from Blue MountainEye Study. The data were analysed using food nutritient dana from McCance and Widdowson's Food Composition Tables, supplemented with a food fatty acid content database (Foodbase, London, UK). We noticed statistically significant difference between omega-6/omega-3 ratio in neovascular ARMD (stage 5) and all other groups including control group (p = 0.000020). The ratio in Stage 5 was about 11:1 like in Western diet. Stage 4-geographic atrophy (GA) has statistically significant difference in o-mega-6/omega-3 ratio compared with stage 1 (p = 0.000571), stage 2 (p = 0.000112) and stage3 (p = 0.000430). The ratio in first three groups is about 7-7.5:1 (greater then Mediteran-4-5:1, but lower then Western Diet-10-20:1). There is no statistically significant difference between first three stages (p > 0.05) and stage 4 and control group (p = 0.172388). Omega-6/omega-3 ratio is connected with development of neovascular ARMD. Decreased ratio protects against neovascular ARMD. On the contrary, GA seems to be connected with prolonged sunlight exposure (the ratio is about 6:1). It is good to know that changing nutrition habits someone can prevent development of severe neovascular form of ARMD because intravitreal anti-VEGF therapy limitations.     

The role of the spectral domain ocular coherence tomography in detection of age-related macular degeneration

Age-related macular degeneration (ARMD) is one of the most common causes of the vision loss and blindness in developed countries. Among other harmful effects, exposure to the UV radiation is the most prominent factor for the development of the disorder. Using the method of SD OCT (Spectral Domain Ocular Coherence Tomography) we performed measurement of the neurosensory retinal thickness of 19 eyes of low vision patients from the population of Primorsko-Goranska County of Republic of Croatia, with dry form of the terminal macular degeneration. These results we compared with control measurements performed on 28 eyes of healthy, normal vision subjects from same County. We determined following parameters: central foveal thickness (CFT), macular volume (MV) and mean foveal thickness (MFT) in the both groups. Results showed statistically significant reduction of CFT in the group of normal vision female patients when compared to males, while any significant difference of CFT between total groups of normal vision individuals and low vision patients was not detected. Furthermore, we noticed statistically significant (p < 0.000001) decrease of the MV in the group of the low vision patients in comparison to healthy subjects and statistically significant (p < 0.000001) reduction of the MFT of the low vision patients when compared to normal vision individuals. In our study we detected the absence of any significant difference of the CFT between healthy and low vision population, what looks like controversial finding, because neurosensory retina in the ARMD is thin and atrophic, but on the other side it is known that fixation point in low vision patients is translocated from the damaged fovea to extrafoveal region, usually above the fovea, where neurosensory retina is of the normal thickness, but with the less sensitivity. Furthermore, our results suggest possible connection of higher incidence of ARMD with lower CFT in females. Owing to the thicker neurosensory retina in males and better protection, damaging effect of the UV irradiation, which is the proven factor of ARMD development, is smaller. From the evolutionary point of view it is possible that males in all vertebrates have more resistant macula because during the evolutionary process they have spent much more time outside in the sunlight than females.