Performance and Value of IFN-Lambda3 and IFN-Lambda4 Genotyping in Patients with Chronic Hepatitis C (CHC) Genotype 2/3 in a Real World Setting

Background

SNPs near the interferon lambda (IFNL) 3 gene are predictors for sustained virological response (SVR) in patients with chronic hepatitis C genotype (GT) 1. In addition, a dinucleotide frame shift in ss469415590 was described, which generates IFNL4. In this study, we compared the role of IFNL4 variants with IFNL3-(rs12979860) and IFNL3-(rs8099917) on response to pegylated (PEG)-IFN and Ribavirin (RBV) in patients with chronic hepatitis C GT2/3.

Methods

We recruited 1006 patients with chronic hepatitis C and GT2/3 in a large German registry. A treatment with PEG-IFN and Ribavirin was started by 959 patients. We performed genotyping of IFNL3 (rs12979860, n = 726; rs8099917, n = 687) and of IFNL4 (ss469415590; n = 631).

Results

Both preferable IFNL3 genotypes were associated with RVR (both p<0.0001) rather than with SVR (rs12979860: p = 0.251; rs8099917: p = 0.447). Only RVR was linked to SVR in univariate and multivariate analyzes (both p<0.001). Concordance of genotyping in patients with available serum samples and EDTA blood samples (n = 259) was more than 96% for both IFNL3 SNPs. IFNL3-(rs12979860) correlated with IFNL4: 99.2% of patients with IFNL3-(rs12979860)-CC were IFNL4-(ss469415590)-TT/TT. IFNL3-(rs12979860)-CT was linked with IFNL4-(ss469415590)-TT/ΔG (98.0%) and IFNL3-(rs12979860)-TT was associated with IFNL4-(ss469415590)-ΔG/ΔG (97.6%).

Conclusion

IFNL3 genotyping from serum was highly efficient and can be used as an alternative if EDTA whole blood is not available. In Caucasian GT2/3 patients genotyping for INFL4-(ss469415590) does not lead to additional information for the decision-making process. Importantly, IFNL3 SNPs were not associated with SVR but with RVR. Even in the era of new direct acting antiviral (DAA) therapies, IFNL3 testing may therefore still be considered for naïve GT2/3 patients to decide if dual Peg-IFN/RBV therapy is an option in resource limited regions.     

Foraging activity of bumblebees (Bombus terrestris L.) on Bt-expressing eggplants

A greenhouse experiment was setup to study foraging behavior of the bumblebee Bombus terrestris L. on Cry3Bb-expressing genetically modified (GM) eggplants and their near-isogenic control. Commonly, more bumblebees visited GM eggplants compared to near-isogenic control, but this difference was only marginally significant. The mean length of feeding bouts was similar on the two treatments. Neither the number of flowers produced nor their size could explain bumblebees?? tendency to prefer GM eggplants. Volatile compounds were extracted from five plants per genotype and separated using gas chromatography. Thirteen compounds were identified and five of them appeared significantly more abundant in GM eggplants. Six of the identified compounds [(+)-limonene, Z-jasmone, p-cymene, ??-pinene, methyl-salicilate, and (?)-limonene] were tested in electrophysiological bioassays with antennas detached from young bumblebees, and a response was recorded in all six cases. Experimental results indicate that pollination activity of bumblebees is compatible with this GM eggplant event as a food source and that chemical cues may have an important role in plant identification. The implications for environmental risk assessment of GM plants are discussed.     

RESIN COLLECTION AND SOCIAL IMMUNITY IN HONEY BEES

Diverse animals have evolved an ability to collect antimicrobial compounds from the environment as a means of reducing infection risk. Honey bees battle an extensive assemblage of pathogens with both individual and "social" defenses. We determined if the collection of resins, complex plant secretions with diverse antimicrobial properties, acts as a colony-level immune defense by honey bees. Exposure to extracts from two sources of honey bee propolis (a mixture of resins and wax) led to a significantly lowered expression of two honey bee immune-related genes (hymenoptaecin and AmEater in Brazilian and Minnesota propolis, respectively) and to lowered bacterial loads in the Minnesota (MN) propolis treated colonies. Differences in immune expression were also found across age groups (third-instar larvae, 1-day-old and 7-day-old adults) irrespective of resin treatment. The finding that resins within the nest decrease investment in immune function of 7-day-old bees may have implications for colony health and productivity. This is the first direct evidence that the honey bee nest environment affects immune-gene expression.     

Trypanosoma cruzi: TcRAB7 protein is localized at the Golgi apparatus in epimastigotes

In mammalian cells, the Rab7 protein is a key element of late endocytic membrane traffic. Several results suggest that it is involved in the transport from early to late endosome or from late endosome to lysosome. We have previously characterized a Rab7 gene homologue (TcRAB7) in Trypanosoma cruzi. Now, using an affinity-purified antibody specific to TcRAB7 protein we have determined that it is localized at the Golgi apparatus of the parasite. Our results indicate that the T. cruzi Rab7 homologue may function in a different route than its counterparts in mammalian cells.     

Rhipicephalus sanguineus trypsin inhibitors present in the tick larvae: isolation,characterization, and partial primary structure determination

Blood sucking animals are a rich source of proteinase inhibitors mainly those that interfere in their host hemostatic systems. The tick Rhipicephalus sanguineus is an ectoparasite of dogs and other animals. The aims of this work were the purification and characterization of serine proteinase inhibitors present in R. sanguineus larvae (RsTI). The inhibitors (RsTI) were isolated by affinity chromatography on trypsin-Sepharose and ion exchange chromatographies in Resource Q and Mono S columns. These RsTIs were separated in around 12 different protein peaks, when they showed molecular masses between 8 and 18 kDa, by SDS-PAGE. Purified RsTIs presented differences in the specificity for different serine proteinases. RsTIQ2 was, better inhibitor than RsTIQ7 and RsTIS5 for neutrophil elastase, plasmin, and HuPK with dissociation constants (K(i)) of 1.3, 3.2, and 22 nM, respectively. Other inhibitors such as RsTIQ7, RsTIS3, and RsTIS5 also affected neutrophil elastase and plasmin with K(i) in the nM range. The RsTIQ2, RsTIQ7, and RsTIS5 amino acid sequence data allowed classifying them as members of the Kunitz-type serine proteinase inhibitor family, even though the RsTI role is still unknown. Our present results showed that serine proteinase inhibitors from R. sanguineus are similar to inhibitors from Boophilus microplus other hard tick species, suggesting a similar role of these inhibitors in hard tick species and also as a potential tool to generate or improve vaccine against different ectoparasites with an unique antigen.     

Reference Equation for Respiratory Pressures in Pediatric Population: A Multicenter Study

Previous studies have proposed only one prediction equation for respiratory muscle strength without taking into consideration differences between ages in pediatric population. In addition, those researches were single-center studies. The objective of this study was to establish reference equations for maximal inspiratory pressure (PImax) and maximal expiratory pressure (PEmax) in children and teenagers. In a multicenter study, 450 healthy volunteers were evaluated (aged 6–18yrs). There were included volunteers with normal lung function. We excluded volunteers who could not perform the tests; participated in physical activity more than twice a week; were born prematurely; smokers; chronic respiratory, cardiologic, and/or neurologic diseases; had acute respiratory disease during the prior three weeks. The volunteers were divided into two groups: Group 6–11 (6–11yrs) and Group 12–18 (12–18yrs). PImax and PEmax were measured according to statement. The mean PImax value was 85.6 (95%IC 83.6–87.6 cmH₂O), and PEmax 84.6 (95%IC 85.5–86.2 cmH₂O). The prediction equations for PImax and PEmax for Group 6–11 were 37.458–0.559 + (age * 3.253) + (BMI * 0.843) + (age * gender * 0.985); and 38.556 + 15.892 + (age * 3.023) + (BMI * 0.579) + (age * gender * 0.881), respectively (R² = 0.34 and 0.31, P<0.001). The equations for Group 12–18 were 92.472 + (gender * 9.894) + 7.103, (R² = 0.27, P = 0.006) for PImax; and 68.113 + (gender * 17.022) + 6.46 + (BMI * 0.927), (R² = 0.34, P<0.0001) for PEmax. This multicenter study determined the respiratory muscle strength prediction equations for children and teenagers.     

Structure of a Highly Conserved Domain of Rock1 Required for Shroom-Mediated Regulation of Cell Morphology

Rho-associated coiled coil containing protein kinase (Rho-kinase or Rock) is a well-defined determinant of actin organization and dynamics in most animal cells characterized to date. One of the primary effectors of Rock is non-muscle myosin II. Activation of Rock results in increased contractility of myosin II and subsequent changes in actin architecture and cell morphology. The regulation of Rock is thought to occur via autoinhibition of the kinase domain via intramolecular interactions between the N-terminus and the C-terminus of the kinase. This autoinhibited state can be relieved via proteolytic cleavage, binding of lipids to a Pleckstrin Homology domain near the C-terminus, or binding of GTP-bound RhoA to the central coiled-coil region of Rock. Recent work has identified the Shroom family of proteins as an additional regulator of Rock either at the level of cellular distribution or catalytic activity or both. The Shroom-Rock complex is conserved in most animals and is essential for the formation of the neural tube, eye, and gut in vertebrates. To address the mechanism by which Shroom and Rock interact, we have solved the structure of the coiled-coil region of Rock that binds to Shroom proteins. Consistent with other observations, the Shroom binding domain is a parallel coiled-coil dimer. Using biochemical approaches, we have identified a large patch of residues that contribute to Shrm binding. Their orientation suggests that there may be two independent Shrm binding sites on opposing faces of the coiled-coil region of Rock. Finally, we show that the binding surface is essential for Rock colocalization with Shroom and for Shroom-mediated changes in cell morphology.     

Some like it hot and some like it cold,but not too much: plant responses to climate extremes

Current climatic models predict increasing frequency and magnitude of extreme climatic events (ECEs). Ecological studies recognize the importance of these extremes as drivers of plant growth and mortality, as well as drivers of ecological and evolutionary processes. Here we review observational and experimental studies on ECEs on herbaceous plants and shrubs. Extreme events considered were heat waves, drought, advanced or delayed snowmelt, heavy rainfalls, frosts, pulsed watering and flooding. We analysed 39 studies dealing with direct response of plant to ECEs in different ecosystems, with a particular focus on cold ecosystems (alpine and arctic). Although the number of studies increases every year, the understanding of ecological consequences of ECEs is fragmentary. In general, ECEs affected negatively on physiological processes (efficiency of photosystem II, stomatal conductance and leaf water potential), productivity and reproduction, and had consequences on population demography and recruitment several years after ECE. Indeed, the plant responses to ECEs were species specific and depended on the plant life stage and the timing of ECE. In fact, the magnitude of the effect of ECEs decreased over the growing season. Drought had the most severe effect on plants, while heat waves had minor effect if water was available. The overlap of different ECEs had an additive effect (e.g. drought associated to heat-waves). In general, both neutral or positive plant responses were found and acclimation is possible. In some cases, ECEs exert a strong selective pressure on plant species.     

Trophic cascades initiated by fungal plant endosymbionts impair reproductive performance of parasitoids in the second generation

Variation in plant quality can transmit up the food chain and may affect herbivores and their antagonists in the same direction. Fungal endosymbionts of grasses change the resource quality by producing toxins. We used an aphid-parasitoid model system to explore how endophyte effects cascade up the food chain and influence individual parasitoid performance. We show that the presence of an endophyte in the grass Lolium perenne has a much stronger negative impact on the performance of the parasitoid Aphidius ervi than on its aphid host Metopolophium festucae. Although the presence of endophytes did not influence the parasitism rate of endophyte-naïve parasitoids or their offspring’s survival to adulthood, most parasitoids developing within aphids from endophyte-infected plants did not reproduce at all. This indicates a delayed but very strong effect of endophytes on parasitoid performance, which should ultimately affect plant performance negatively by releasing endophyte-tolerant herbivores from top-down limitations.