Intranasal delivery of HMGB1-binding heptamer peptide confers a robust neuroprotection in the postischemic brain

High mobility group box 1 (HMGB1) is an endogenous danger signal molecule. In a previous report, we showed that HMGB1 is massively released during NMDA-induced acute damaging process in the postischemic brain and triggers inflammatory processes and induces neuronal apoptosis. We have also reported a robust neuroprotection of intranasally delivered HMGB1 siRNA in the postischemic rat brain (middle cerebral artery occlusion (MCAO), 60min). In the present study, we investigated the therapeutic efficacy of intranasally delivered HMGB1 binding heptamer peptide (HBHP; HMSKPVQ), which was selected using a phage display approach, in the same stroke animal model. A pull-down assay using biotin-labeled HBHP showed that HBHP binds directly to HMGB1, specifically to HMGB1 A box, confirming HMGB1/HBHP interaction. HBHP significantly suppressed HMGB1-mediated neuronal cell death in primary cortical cultures and HMGB1/HBHP binding was detected in NMDA-conditioned culture media. However, a heptamer peptide composed of a scrambled sequence of the seven amino acids in HBHP failed to bind HMGB1 and had no protective effect. Furthermore, HBHP (300ng) delivered intranasally at 30min before MCAO significantly suppressed infarct volume in the postischemic rat brain (maximal reduction by 41.8±5.4%) and ameliorated neurological and behavioral deficits. In contrast, scrambled heptamer peptide had no protective effect at the same dose. Together these results suggest that intranasal HBHP ameliorates neuronal damage in the ischemic brain by binding HMGB1, which might inhibit the function of HMGB1 as an endogenous danger signal molecule.     

Efficacy of vaccination strategies against intranasal challenge with Brucella abortus in BALB/c mice

Brucellosis is a zoonotic disease affecting 500,000 people worldwide annually. Inhalation of aerosol containing a pathogen is one of the major routes of disease transmission in humans. Currently there are no licensed human vaccines available. Brucella abortus strain RB51 is a USDA approved live attenuated vaccine against cattle brucellosis. In a mouse model, strain RB51 over-expressing superoxide dismutase (SOD) administered intraperitoneally (IP) has been shown to be more protective than strain RB51 against an IP challenge with B. abortus pathogenic strain 2308. However, there is lack of information on the ability of these vaccine strains to protect against intranasal challenge. With the long-term goal of developing a protective vaccine for animals and people against respiratory challenge of Brucella spp., we tested a number of different vaccination strategies against intranasal infection with strain 2308. We employed strains RB51 and RB51SOD to assess the efficacy of route, dose, and prime-boost strategies against strain 2308 challenge. Despite using multiple protocols to enhance mucosal and systemic protection, neither rough RB51 vaccine strains provided respiratory protection against intranasal pathogenic Brucella infection. However, intranasal (IN) administration of B. abortus vaccine strain 19 induced significant (p ≤ 0.05) pulmonary clearance of strain 2308 upon IN challenge infection compared to saline. Further studies are necessary to address host-pathogen interaction in the lung microenvironment and elucidate immune mechanisms to enhance protection against aerosol infection.     

A sniff of trust: meta-analysis of the effects of intranasal oxytocin administration on face recognition, trust to in-group, and trust to out-group

The neuropeptide oxytocin has a popular reputation of being the 'love' hormone. Here we test meta-analytically whether experiments with intranasal administration of oxytocin provide support for the proposed effects of oxytocin. Three psychological effects were subjected to meta-analysis: facial emotion recognition (13 effect sizes, N=408), in-group trust (8 effect sizes, N=317), and out-group trust (10 effect sizes; N=505). We found that intranasal oxytocin administration enhances the recognition of facial expressions of emotions, and that it elevates the level of in-group trust. The hypothesis that out-group trust is significantly decreased in the oxytocin condition was not supported. It is concluded that a sniff of oxytocin can change emotion perception and behavior in trusting relationships.     

Identification of Francisella tularensis outer membrane protein A (FopA) as a protective antigen for tularemia

Francisella tularensis is a highly pathogenic gram negative bacterium that infects multiple sites in a host, including the skin and the respiratory tract, which can lead to the onset of a deadly disease with a 50% mortality rate. The live vaccine strain (LVS) of F. tularensis, while attenuated in humans but still virulent in mice, is not an option for vaccine use in the United States due to safety concerns, and currently no FDA approved vaccine exists. The purpose of the present work was to assess the ability of recombinant Francisella outer membrane protein A (FopA) to induce a protective response in mice. The gene encoding FopA from F. tularensis LVS was cloned and expressed in Escherichia coli. The resulting recombinant protein was affinity-purified from the E. coli outer membrane, incorporated into liposomes and administered to mice via multiple routes. FopA-immunized mice produced FopA-specific antibodies and were protected against both lethal intradermal and intranasal challenges with F. tularensis LVS. The vaccinated mice had reduced bacterial numbers in their lungs, livers and spleens during infection, and complete bacterial clearance was observed by day 28 post infection. Passive transfer of FopA-immune serum protected naïve mice against lethal F. tularensis LVS challenge, showing that humoral immunity played an important role in vaccine efficacy. FopA-immunization was unable to protect against challenge with the fully virulent SchuS4 strain of F. tularensis; however, the findings demonstrate proof of principle that an immune response generated against a component of a subunit vaccine is protective against lethal respiratory and intradermal tularemia.     

Intranasal hydromorphone for treatment of acute pain in children: A pilot study

ObjectivesWe aimed to describe the analgesic efficacy, duration of analgesia, and adverse event profile associated with intranasal hydromorphone in children with acute pain presenting to an emergency department.MethodsProspective dose titration pilot study of otherwise healthy children 4 to 17-years-old with moderate to severe pain who required a parenteral opioid. All patients received an initial intranasal hydromorophone dose of 0.03 mg/kg. The need for additional analgesia was assessed at 15 and 30 min; an additional 0.015 mg/kg was given at each assessment, if required. Need for rescue analgesic, pain intensity and adverse events were assessed until 6 h after hydromorphone administration or until patients were discharged, underwent a procedure to treat their painful condition, or received a rescue analgesic.ResultsWe enrolled 35 children. Fifteen, 11, and 9 children required a total dose of 0.03, 0.045, and 0.06 mg/kg, respectively. Patients in each dose group experienced an absolute decrease in pain score of ≥3/10 and percent reduction >40% within 5–15 min of completing dose-titration administration of hydromorphone. Duration of analgesia (i.e. time until rescue analgesic administered) >1 h was observed in 85.7% of patients. Patients not requiring rescue analgesics had mild or no pain until discharged or their painful conditions were treated. Three (8.6%) patients required a rescue analgesic <1 h after hydromorphone administration. There were no major adverse events.ConclusionsIntranasal hydromorphone led to rapid, clinically significant and frequently sustained decreases in pain intensity in children. No major adverse events were observed in this preliminary sample.Clinical Trials Registration Number: NCT02437669     

Effects of a projector-based hybrid virtual reality on pain in young children with burn injuries during hydrotherapy sessions: A within-subject randomized crossover trial

AimThe aim of this study was to examine the effect of a water-friendly Projector-Based Hybrid Virtual Reality (VR) dome environment combined with standard pharmacological treatment on pain in young children undergoing burn wound care in hydrotherapy.MethodsThis study was a prospective, within-subject crossover trial of 38 children aged 6 months to 7 years old (mean age = 1.8 years old). Each hydrotherapy procedure was divided into two equivalent wound care segments (No hybrid VR during one segment vs. Hybrid VR during the other segment, treatment order was randomized). Pain was measured using the 0–10 FLACC (Face, Legs, Activity, Cry Consolability scale) and the 0–10 NRS-obs (Numerical Rating Scale-obs).ResultsProjector-Based Hybrid VR significantly reduced procedural pain levels measured by the FLACC (p = 0.026) and significantly increased patients' comfort levels (p = 0.002). Patients' pain levels rated by the nurses using the NRS-obs were non-significant between both groups (p = 0.135). No side effects were reported.ConclusionProjector-Based Hybrid VR helped in reducing the pain related to hydrotherapy procedures in young children with burn wound injuries. This is the first study using virtual reality distraction with young children, and our findings are especially important because a large percentage of pediatric burn patients are very young. Additional research and development are recommended.Trial registrationClinicalTrials.gov, NCT02986464, registered on June 12, 2016.     

A randomized,double-blind,controlled clinical trial to evaluate the safety and immunogenicity of an intranasally administered trivalent inactivated influenza vaccine with adjuvant LTh(αK): A phase I study

Background

A nasal influenza vaccine has been available only in a live attenuated form, which limits the range of recipients to immune-competent individuals. The present study evaluated a newly developed intranasal inactivated influenza vaccine with a novel adjuvant, heat-labile enterotoxin (LT) derived from E. coli (LTh(αK)).

Intranasal immunization with liposomes induces strong mucosal immune responses in mice

BALB/c mice were immunized intranasally with either soluble ovalbumin (OVA) or OVA entrapped in liposomes. The effect of adding Sigma cholera toxin B subunit (sCT-B), which contained low amounts of cholera holotoxin (CT), or recombinant CT-B (rCT-B) which was free from CT, as mucosal adjuvants was also investigated. The mucosal [lung enzyme-linked immunospot assay (ELISPOT), lung washing] and systemic (serum antibody and spleen ELISPOT) responses of immunized mice to OVA and CT-B were determined. Results showed that soluble OVA and liposome-entrapped OVA were poor inducers of mucosal or systemic responses unless CT-B was added as adjuvant. The types of responses augmented by sCT-B and rCT-B were different. CT-B containing low levels of CT (i.e. sCT-B) boosted both mucosal and systemic IgA and IgG responses, whereas rCT-B only increased IgG responses, unless antigen was entrapped in liposomes. Although rCT-B was unable to adjuvant IgA responses against soluble OVA, it was able to induce IgA responses against itself. These data show that mucosal responses can be increased by addition of CT-B containing low levels of CT to antigen preparations given intranasally, suggesting a direct role for CT-A in isotype switching. Furthermore, the ability of CT-B to adjuvant IgA responses against added antigens and its ability to induce responses against itself appear to be separate phenomena. The results from this study should assist the rational formulation of mucosal vaccines which induce potent mucosal and systemic immune responses.     

The road to a more effective influenza vaccine: Up to date studies and future prospects

Influenza virus causes an acute respiratory infection in humans. Frequent point mutations in the influenza genome and occasional exchange of genetic segments between virus strains help the virus evade the pre-existing immunity, resulting in epidemics and pandemics. Although vaccination is the most effective intervention, mismatches between circulating viruses and vaccine strains reduce vaccine efficacy. Furthermore, current injectable vaccines induce IgG antibodies in serum (which limit progression of influenza symptoms) but not secretory IgA antibodies in the respiratory mucosa (which prevent virus infection efficiently). Therefore, numerous studies have attempted to improve influenza vaccines. The discovery of broadly neutralizing antibodies has progressed research into antigen design. Studies designed to improve vaccine efficacy by changing the vaccine administration route have also been conducted. A thorough understanding of the mechanisms underlying the action of various vaccines is essential if we are to develop a universal influenza vaccine. Therefore, evaluating the quality and quantity of antibodies induced by vaccines, which determine vaccine efficacy, is critical. However, at present vaccine evaluation relies on hemagglutination inhibition tests, which only measure the quantity of antibody produced. Antibody repertoires comprise a set of antibodies with specific genetic or molecular features that correspond to their functions. Genetically and functionally similar antibodies may be produced by multiple individuals exposed to an identical stimulus. Therefore, it may be possible to evaluate and compare multiple vaccine strategies in terms of the quality and quantity of an antibody response induced by a vaccine by examining antibody repertoires. Recent studies have used single cell expression and high-throughput immunoglobulin sequencing to provide a detailed picture of antibody responses. These novel methods may be critical for detailed characterization of antibody repertoires induced by various vaccination strategies.