IL-1beta stimulates rat cardiac fibroblast migration via MAP kinase pathways

The pro-inflammatory cytokines interleukin-1beta (IL-1beta), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-alpha) are elevated following acute myocardial infarction (MI) and have been implicated in the pathophysiology of cardiac disease progression. The cardiac fibroblast represents an important effector cell target for cytokine actions. In particular, cytokine-directed cardiac fibroblast migration is likely to impact both myocardial repair following acute MI and pathological myocardial remodeling in the progression to heart failure. In the present study, we examined the migratory response of neonatal rat cardiac fibroblasts to pro-inflammatory cytokines using modified Boyden chamber assays. On the basis of the knowledge of migration in other cell types, we hypothesized that members of the mitogen-activated protein kinase (MAPK) family may regulate this process. This possibility was addressed with the use of immunoblot detection of active phosphorylated MAPK species and pharmacological inhibitors for individual members of the MAPK cascades. IL-1beta stimulated robust and concentration-dependent increases in migration (maximum, 20-fold over control cells). TNF-alpha had lesser effect (fourfold increase over control). IL-6 did not induce migration. Activation of all three MAPK subfamilies (extracellular signal-regulated kinases, c-Jun NH(2)-terminal kinases, and p38) was shown to occur in response to cytokine stimulation. Fibroblast migration was attenuated by pharmacological inhibition of each MAPK subfamily. Understanding the regulation of cardiac fibroblast migration may provide insights in the search for therapies aimed at enhancing the functional nature of the remodeling process.     

Phase I randomised clinical trial of an HIV-1(CN54), clade C, trimeric envelope vaccine candidate delivered vaginally

We conducted a phase 1 double-blind randomised controlled trial (RCT) of a HIV-1 envelope protein (CN54 gp140) candidate vaccine delivered vaginally to assess immunogenicity and safety. It was hypothesised that repeated delivery of gp140 may facilitate antigen uptake and presentation at this mucosal surface. Twenty two healthy female volunteers aged 18-45 years were entered into the trial, the first receiving open-label active product. Subsequently, 16 women were randomised to receive 9 doses of 100 μg of gp140 in 3 ml of a Carbopol 974P based gel, 5 were randomised to placebo solution in the same gel, delivered vaginally via an applicator. Participants delivered the vaccine three times a week over three weeks during one menstrual cycle, and were followed up for two further months. There were no serious adverse events, and the vaccine was well tolerated. No sustained systemic or local IgG, IgA, or T cell responses to the gp140 were detected following vaginal immunisations. Repeated vaginal immunisation with a HIV-1 envelope protein alone formulated in Carbopol gel was safe, but did not induce local or systemic immune responses in healthy women. TRIAL REGISTRATION: ClinicalTrials.gov NCT00637962.     

Detection of Rapalog-Mediated Therapeutic Response in Renal Cancer Xenografts Using 64Cu-bevacizumab ImmunoPET

The importance of neovascularization for primary and metastatic tumor growth fostered numerous clinical trials of angiogenesis inhibitors either alone or in combination with conventional antineoplastic therapies. One challenge with the use of molecularly targeted agents has been the disconnection between size reduction and tumor biologic behavior, either when the drug is efficacious or when tumor resistance emerges. Here, we report the synthesis and characterization of ⁶⁴Cu-NOTA-bevacizumab as a PET imaging agent for imaging intratumoral VEGF content in vivo. ⁶⁴Cu-NOTA-bevacizumab avidly accumulated in 786-O renal carcinoma xenografts with lower levels in host organs. RAD001 (everolimus) markedly attenuated ⁶⁴Cu-NOTA-bevacizumab accumulation within 786-O renal carcinoma xenografts. Tumor tissue and cellular molecular analysis validated PET imaging, demonstrating decreases in total and secreted VEGF content and VEGFR2 activation. Notably, ⁶⁴Cu-NOTA-bevacizumab PET imaging was concordant with the growth arrest of RAD001 tumors. These data suggest that immunoPET targeting of angiogenic factors such as VEGF could be a new class of surrogate markers complementing the RECIST criteria in patients receiving molecularly targeted therapies.     

Mastl is required for timely activation of APC/C in meiosis I and Cdk1 reactivation in meiosis II

In mitosis, the Greatwall kinase (called microtubule-associated serine/threonine kinase like [Mastl] in mammals) is essential for prometaphase entry or progression by suppressing protein phosphatase 2A (PP2A) activity. PP2A suppression in turn leads to high levels of Cdk1 substrate phosphorylation. We have used a mouse model with an oocyte-specific deletion of Mastl to show that Mastl-null oocytes resume meiosis I and reach metaphase I normally but that the onset and completion of anaphase I are delayed. Moreover, after the completion of meiosis I, Mastl-null oocytes failed to enter meiosis II (MII) because they reassembled a nuclear structure containing decondensed chromatin. Our results show that Mastl is required for the timely activation of anaphase-promoting complex/cyclosome to allow meiosis I exit and for the rapid rise of Cdk1 activity that is needed for the entry into MII in mouse oocytes.     

Gestational Heat Stress Alters Postnatal Offspring Body Composition Indices and Metabolic Parameters in Pigs

The study objectives were to test the hypothesis that heat stress (HS) during gestational development alters postnatal growth, body composition, and biological response to HS conditions in pigs. To investigate this, 14 first parity crossbred gilts were exposed to one of four environmental treatments (TNTN, TNHS, HSTN, or HSHS) during gestation. TNTN and HSHS dams were exposed to thermal neutral (TN, cyclical 18–22°C) or HS conditions (cyclical 28–34°C) during the entire gestation, respectively. Dams assigned to HSTN and TNHS treatments were heat-stressed for the first or second half of gestation, respectively. Postnatal offspring were exposed to one of two thermal environments for an acute (24 h) or chronic (five weeks) duration in either constant TN (21°C) or HS (35°C) environment. Exposure to chronic HS during their growth phase resulted in decreased longissimus dorsi cross-sectional area (LDA) in offspring from HSHS and HSTN treated dams whereas LDA was larger in offspring from dams in TNTN and TNHS conditions. Irrespective of HS during prepubertal postnatal growth, pigs from dams that experienced HS during the first half of gestation (HSHS and HSTN) had increased (13.9%) subcutaneous fat thickness compared to pigs from dams exposed to TN conditions during the first half of gestation. This metabolic repartitioning towards increased fat deposition in pigs from dams heat-stressed during the first half of gestation was accompanied by elevated blood insulin concentrations (33%; P = 0.01). Together, these results demonstrate HS during the first half of gestation altered metabolic and body composition parameters during future development and in biological responses to a subsequent HS challenge.     

Long‐range movement by Hector's dolphins provides potential genetic enhancement for critically endangered Maui's dolphin

For endangered populations with low genetic diversity, low levels of immigration could lead to genetic rescue, reducing the risk of inbreeding depression and enhancing chances of long‐term species survival. Our genetic monitoring of Maui's dolphins revealed the first contemporary dispersal of their sister subspecies, Hector's dolphin, from New Zealand's South Island into the Maui's dolphin distribution along ~300 km of the North Island's northwest coast. From 2010 to 2012, 44 individuals were sampled within the Maui's dolphin distribution, four of which were genetically identified as Hector's dolphins (two living females, one dead female, one dead male). We also report two Hector's dolphins (one dead female neonate, one living male) sampled along the North Island's southwest coast, outside the presumed range of either subspecies. Together, these records demonstrate long‐distance dispersal by Hector's dolphins (≥400 km) and the possibility of an unsampled Hector's dolphin population along the southwest coast of the North Island. Although two living Hector's dolphins were found in association with Maui's dolphins, there is currently no evidence of interbreeding between the subspecies. These results highlight the value of genetic monitoring for subspecies lacking distinctive physical appearances as such discoveries are not detected by other means, but have important conservation implications.     

Extending Serum Half-life of Albumin by Engineering Neonatal Fc Receptor (FcRn) Binding

A major challenge for the therapeutic use of many peptides and proteins is their short circulatory half-life. Albumin has an extended serum half-life of 3 weeks because of its size and FcRn-mediated recycling that prevents intracellular degradation, properties shared with IgG antibodies. Engineering the strictly pH-dependent IgG-FcRn interaction is known to extend IgG half-life. However, this principle has not been extensively explored for albumin. We have engineered human albumin by introducing single point mutations in the C-terminal end that generated a panel of variants with greatly improved affinities for FcRn. One variant (K573P) with 12-fold improved affinity showed extended serum half-life in normal mice, mice transgenic for human FcRn, and cynomolgus monkeys. Importantly, favorable binding to FcRn was maintained when a single-chain fragment variable antibody was genetically fused to either the N- or the C-terminal end. The engineered albumin variants may be attractive for improving the serum half-life of biopharmaceuticals.     

Sensitive periods during the development and expression of vertebrate sexual signals: A systematic review

Many sexually selected traits exhibit phenotypic plasticity. Despite a growing appreciation for the ecological context in which sexual selection occurs, and for the role of plasticity in shaping traits associated with local adaptation and divergence, there is an important gap in knowledge about the onset and duration of plasticity in sexual trait expression. Integrating this temporal dimension of plasticity into models of sexual selection informs our understanding of the information conveyed by sexual traits and our predictions related to trait evolution, and is critical in this time of unprecedented and rapid environmental change. We conducted a systematic review of 869 studies to ask how trait modalities (e.g., visual and chemical) relate to the onset and duration of plasticity in vertebrate sexual signals. We show that this literature is dominated by studies of coloration in birds and fish, and most studies take place during the breeding season. Where possible, we integrate results across studies to link physiology of specific trait modalities with the life stage (e.g., juvenile, breeding, or nonbreeding) during which plasticity occurs in well‐studied traits. Limitations of our review included a lack of replication in our dataset, which precluded formal analysis. We argue that the timing of trait plasticity, in addition to environmental context, is critical for determining whether and how various communication signals are associated with ecological context, because plasticity may be ongoing or occur at only one point in an individual''s lifetime, and determining a fixed trajectory of trait expression. We advocate for careful consideration of the onset and duration of plasticity when analyzing how environmental variation affects sexual trait expression and associated evolutionary outcomes.