TRIM15 is a focal adhesion protein that regulates focal adhesion disassembly.

Focal adhesions are macromolecular complexes that connect the actin cytoskeleton to the extracellular matrix. Dynamic turnover of focal adhesions is crucial for cell migration. Paxillin is a multi-adaptor protein that plays an important role in regulating focal adhesion dynamics. Here, we identify TRIM15, a member of the tripartite motif protein family, as a paxillin-interacting factor and a component of focal adhesions. TRIM15 localizes to focal contacts in a myosin-II-independent manner by an interaction between its coiled-coil domain and the LD2 motif of paxillin. Unlike other focal adhesion proteins, TRIM15 is a stable focal adhesion component with restricted mobility due to its ability to form oligomers. TRIM15-depleted cells display impaired cell migration and reduced focal adhesion disassembly rates, in addition to enlarged focal adhesions. Thus, our studies demonstrate a cellular function for TRIM15 as a regulatory component of focal adhesion turnover and cell migration.

Virus-Like Vesicle-Based Therapeutic Vaccine Vectors for Chronic Hepatitis B Virus Infection.

UNLABELLED: More than 500,000 people die each year from the liver diseases that result from chronic hepatitis B virus (HBV) infection. Therapeutic vaccines, which aim to elicit an immune response capable of controlling the virus, offer a potential new treatment strategy for chronic hepatitis B. Recently, an evolved, high-titer vaccine platform consisting of Semliki Forest virus RNA replicons that express the vesicular stomatitis virus glycoprotein (VSV G) has been described. This platform generates virus-like vesicles (VLVs) that contain VSV G but no other viral structural proteins. We report here that the evolved VLV vector engineered to additionally express the HBV middle surface envelope glycoprotein (MHBs) induces functional CD8 T cell responses in mice. These responses were greater in magnitude and broader in specificity than those obtained with other immunization strategies, including recombinant protein and DNA. Additionally, a single immunization with VLV-MHBs protected mice from HBV hydrodynamic challenge, and this protection correlated with the elicitation of a CD8 T cell recall response. In contrast to MHBs, a VLV expressing HBV core protein (HBcAg) neither induced a CD8 T cell response in mice nor protected against challenge. Finally, combining DNA and VLV-MHBs immunization led to induction of HBV-specific CD8 T cell responses in a transgenic mouse model of chronic HBV infection. The ability of VLV-MHBs to induce a multispecific T cell response capable of controlling HBV replication, and to generate immune responses in a tolerogenic model of chronic infection, indicates that VLV vaccine platforms may offer a unique strategy for HBV therapeutic vaccination. IMPORTANCE: HBV infection is associated with significant morbidity and mortality. Furthermore, treatments for chronic infection are suboptimal and rarely result in complete elimination of the virus. Therapeutic vaccines represent a unique approach to HBV treatment and have the potential to induce long-term control of infection. Recently, a virus-based vector system that combines the nonstructural proteins of Semliki Forest virus with the VSV glycoprotein has been described. In this study, we used this system to construct a novel HBV vaccine and demonstrated that the vaccine is capable of inducing virus-specific immune responses in mouse models of acute and chronic HBV replication. These findings highlight the potential of this new vaccine system and support the idea that highly immunogenic vaccines, such as viral vectors, may be useful in the treatment of chronic hepatitis B.

Type III interferon attenuates a vesicular stomatitis virus-based vaccine vector.

UNLABELLED: Vesicular stomatitis virus (VSV) has been extensively studied as a vaccine vector and oncolytic agent. Nevertheless, safety concerns have limited its widespread use in humans. The type III lambda interferon (IFN-λ) family of cytokines shares common signaling pathways with the IFN-α/ß family and thus evokes similar antiviral activities. However, IFN-λ signals through a distinct receptor complex that is expressed in a cell type-specific manner, which restricts its activity to epithelial barriers, particularly those corresponding to the respiratory and gastrointestinal tracts. In this study, we determined how IFN-λ expression from recombinant VSV would influence vector replication, spread, and immunogenicity. We demonstrate that IFN-λ expression severely attenuates VSV in cell culture. In vivo, IFN-λ limits VSV replication in the mouse lung after intranasal administration and reduces virus spread to other organs. Despite this attenuation, however, the vector retains its capacity to induce protective CD8 T cell and antibody responses after a single immunization. These findings demonstrate a novel method of viral vector attenuation that could be used in both vaccine and oncolytic virus applications. IMPORTANCE: Viruses such as VSV that are used as vaccine vectors can induce protective T cell and antibody responses after a single dose. Additionally, IFN-λ is a potent antiviral agent that has certain advantages for clinical use compared to IFN-α/ß, such as fewer patient side effects. Here, we demonstrate that IFN-λ attenuates VSV replication and spread following intranasal virus delivery but does not reduce the ability of VSV to induce potent protective immune responses. These findings demonstrate that the type III IFN family may have widespread applicability for improving the safety and efficacy of viral vaccine and oncolytic vectors.

Revitalizing pancreas transplantation: creation of a hands-on training course for pancreas allograft procurement, backbench preparation, and transplantation.

Despite a steady increase in the number of organs available for transplant in the United States, over the last two decades there has been a precipitous decrease in the annual number of pancreas transplants performed. One overlooked consequence of this decline in pancreas transplant volume has been a decrease in experience in proper pancreas procurement and transplantation techniques for transplant surgeons as well as fewer trained abdominal transplant fellows entering the workforce certified for pancreas procurement and transplantation, with those achieving certification having less-developed judgment, skills, and experience. To augment current fellowship training and provide a concentrated experience in pancreas procurement and transplantation, the ASTS developed a hands-on surgical skills workshop focused on proper techniques for pancreas allograft procurement and backbench preparation.

Cooperation and the scale of competition in humans.

Explaining cooperation is one of the greatest challenges for evolutionary biology. It is particularly a problem in species such as humans, where there is cooperation between nonrelatives. Numerous possible solutions have been suggested for the problem of cooperation between nonrelatives, including punishment, policing, and various forms of reciprocity. Here, we suggest that local competition for resources can pose a problem for these hypotheses, analogous to how it can select against cooperation between relatives. We extend the prisoner's dilemma (PD) game to show that local competition between interacting individuals can reduce selection for cooperation between nonrelatives. This is because, with local competition, fitness is relative to social partners, and cooperation benefits social partners. We then test whether nonrelated humans adjust their level of cooperation facultatively in response to the scale of competition when playing the PD for cash prizes. As predicted, we found that individuals were less likely to cooperate when competition was relatively local. Cooperation between humans will therefore be most likely when repeated interactions take place on a local scale between small numbers of people, and competition for resources takes place on a more global scale among large numbers of people.

Key apoptotic genes APAF1 and CASP9 implicated in recurrent folate-resistant neural tube defects.

Neural tube defects (NTDs) remain one of the most serious birth defects, and although genes in several pathways have been implicated as risk factors for neural tube defects via knockout mouse models, very few molecular causes in humans have been identified. Whole exome sequencing identified deleterious variants in key apoptotic genes in two families with recurrent neural tube defects. Functional studies in fibroblasts indicate that these variants are loss-of-function, as apoptosis is significantly reduced. This is the first report of variants in apoptotic genes contributing to neural tube defect risk in humans.

An ELISPOT-Based Assay to Measure HBV-Specific CD8+ T Cell Responses in Immunocompetent Mice.

Despite some important limitations, immunocompetent mouse models of HBV replication remain an essential tool for studying cellular and humoral immunity to the virus. CD8+ T cells are a critical component of the immune response to HBV due to their ability to both kill virus-infected hepatocytes and produce cytokines such as IFN-γ that non-cytopathically inhibit virus replication. A number of techniques can be used to measure the magnitude, specificity, and functionality of HBV-specific CD8+ T cells, each having its own unique advantages. We describe here the enzyme-linked immunospot (ELISPOT)-based assay, which, compared to other methods, is sensitive, cost-effective, and rapid and requires relatively little optimization, specialized training, or equipment.

Safety and Tolerability of Fingolimod in Latin American Patients with Relapsing-Remitting Multiple Sclerosis: The Open-Label FIRST LATAM Study.

INTRODUCTION: Fingolimod 0.5 mg is an orally active sphingosine 1-phosphate receptor modulator approved for use in adults with relapsing multiple sclerosis (MS). The efficacy and safety profile of fingolimod has been well characterized in a large clinical development program. Here, we report the safety and tolerability of fingolimod in relapsing-remitting MS (RRMS) patients from Latin America. METHODS: A total of 162 patients with RRMS, predominantly from Latin American countries (138/162), were enrolled in this 16-week, single treatment arm, open-label, multi-center study. Unlike the phase III pivotal studies, this study permitted enrollment of patients with controlled diabetes, certain cardiac and pulmonary conditions, older age, and higher baseline Expanded Disability Status Scale. All patients were monitored clinically for a minimum of 6 hours after the first dose. Safety and tolerability assessments were based on adverse events, clinically notable laboratory abnormalities, vital signs, ophthalmic examinations, and electrocardiograms. RESULTS: Overall, the safety and tolerability profile was consistent with that reported previously in phase 3 studies and the FIRST study. Adverse events (AEs) were predominantly mild (n = 49, 35.5%) or moderate (n = 27, 19.6%). Three patients (2.2%) discontinued fingolimod due to AEs. Infections were reported in 33 patients (23.9%) and were predominantly mild in nature (n = 28, 20.3%). Increases in alanine aminotransferase enzymes of ≥3, ≥5 and ≥10 upper limit of normal were reported in five (3.7%), three (2.2%) and one (0.7%) patients, respectively. Hypertension cases (n = 3; 2.2%) did not result in treatment discontinuation and were controlled with antihypertensive therapy. Following first-dose administration, the majority of patients (90.6%) were discharged at 6 h. During the first-dose monitoring, 5 cases of bradycardia were reported; none required extended monitoring or treatment for symptomatic bradycardia. CONCLUSION: The first dose of fingolimod 0.5 mg was well tolerated in RRMS patients from Latin America. The overall safety profile was clinically manageable and consistent with previous fingolimod studies. FUNDING: Novartis. TRIAL REGISTRATION: ClinicalTrials.gov #NCT01497262.

Healthcare resource use and relapses with fingolimod versus natalizumab for treating multiple sclerosis: a retrospective US claims database analysis.

OBJECTIVE: Healthcare resource utilization in patients with multiple sclerosis (MS) is linked to relapses and disease progression. This retrospective cohort database analysis compared healthcare resource use and proxy measures of relapse outcomes in patients with active disease who switched to fingolimod or natalizumab. METHODS: Using administrative claims data from the US PharMetrics Plus database, we identified patients with an MS diagnosis and a claim for fingolimod or natalizumab between 1 October 2010 and 30 June 2012 (index period) who had experienced a relapse (identified using a claims-based algorithm) and used other disease-modifying therapies (DMTs) in the previous year. Patients in the fingolimod and natalizumab cohorts were propensity score matched (1:1). MS-related inpatient stays, corticosteroid use and the proportion of patients experiencing claims-based relapses were assessed in the pre-index and post-index persistence periods. Time to first claims-based relapse in the post-index persistence period was assessed using a Kaplan-Meier curve. RESULTS: The study included 623 unmatched patients (299 and 324 patients in the fingolimod and natalizumab cohorts, respectively) and 370 matched patients (185 in each cohort). In the matched analysis, MS-related inpatient stays and corticosteroid use were similar in the fingolimod and natalizumab cohorts during the post-index persistence period, and were significantly reduced versus the pre-index period (p < 0.01). A similar proportion of patients in the fingolimod and natalizumab cohorts were free from claims-based relapses in the persistence period (68.1% and 68.6%, respectively). There was no significant difference in the likelihood of experiencing a claims-based relapse (p = 0.8696). LIMITATION: Identification of relapses is based on database claims rather than on clinical assessment. CONCLUSIONS: In analyses of patients with MS with a history of relapse and DMT use, fingolimod and natalizumab reduce healthcare resource utilization and have similar effectiveness in a real-world setting.

Functional characterization of the putative hepatitis B virus core protein late domain using retrovirus chimeras.

The hepatitis B virus (HBV) Core protein encodes a late (L)-domain like motif (129PPAYRPPNAP(138)) that has been purported to serve as a docking site for recruitment of host factors such as Nedd4 that can mediate viral particle release from infected cells. However, mutation of this region of Core typically disrupts nucleocapsid formation in the cytoplasm, making it difficult to ascertain if the Core PPAY motif constitutes a functional L-domain that mediates HBV release in the context of replicating virus. Since many viral L-domains are functionally interchangeable between different virus families, and such swapping experiments have been used as a tool to identify other viral sequences with L-domain activity, we generated chimeric constructs between murine leukemia virus (MLV) Gag and HBV Core to determine if the potential HBV L-domain motif is sufficient to stimulate virus release. We found that the HBV Core PPAY motif, but not the PNAP motif, demonstrates L-domain activity in the context of MLV replication to direct virus release and infectious virion production. Additionally, we found that overexpression of the cellular Nedd4 or WWP1 ubiquitin ligases stimulates release of a partially defective PPAY domain mutant, providing further evidence supporting a role for the Nedd4 ubiquitin ligase in promoting HBV release. These studies lend further insight into the mechanisms used by HBV to mediate its release from infected cells.

Acute stress exposure prior to influenza vaccination enhances antibody response in women.

Animal studies have shown that an acute stressor in close temporal proximity to immune challenge can enhance the response to delayed-type hypersensitivity and antibody response to vaccination. The current study examined the effects of acute exercise or mental stress prior to influenza vaccination on the subsequent antibody response to each of the three viral strains. Sixty young healthy adults (31 men, 29 women) were randomly allocated to one of three task conditions: dynamic exercise, mental stress, or control. After an initial baseline, participants completed their allocated 45 min task and then received the influenza vaccine. Plasma cortisol and interleukin-6 were determined at the end of baseline, after the task, and after 60 min recovery. Antibody titres were measured pre-vaccination and at 4 weeks and 20 weeks post-vaccination follow-ups. For the A/Panama strain, women in both the exercise and mental stress conditions showed higher antibody titres at both 4 and 20 weeks than those in the control condition, while men responded similarly in all conditions. Interleukin-6 at +60 min recovery was found to be a significant predictor of subsequent A/Panama antibody response in women. In line with animal research, the current study provides preliminary evidence that acute stress can enhance the antibody response to vaccination in humans.