Salbutamol powder inhaled from the Diskhaler compared to salbutamol as nebulizer solution in severe chronic airways obstruction

AbstractThe bronchodilatory effect of four doses of salbutamol powder (1·6 mg) from a multi-dose dry powder inhaler, the Diskhaler, was compared to the effect of 2·5 ml salbutamol nebulizer solution (1 mg ml−1) from a jet nebulizer, Pari Inhalierboy, in a randomized, double-blind, double-dummy, cross-over study performed on 2 consecutive days. Thirty-two patients with severe chronic obstructive pulmonary disease (COPD), a mean FEV1=29% of predicted value, and at least a 15% increase in FEV1 after inhaling 5 mg nebulized terbutaline were included. Twenty-eight patients were evaluated: 17 women and 11 men with a mean age of 67 years (range 53–82 years). The mean increases in FEV1 were greater after inhalation via the Diskhaler, although there was no difference in the patients' subjective assessment of the treatments. The powder inhaler was also effective in patients with the lowest baseline FEV1 and the lowest inspiratory peak flow through the inhaler. The study demonstrates that dry powder inhalation of salbutamol via a Diskhaler is at least as effective as inhalation of salbutamol via a jet nebulizer in providing bronchodilation in patients with severe COPD

Simian immunodeficiency virus (SIV)-specific CD8+ cytotoxic T lymphocyte responses of naive and vaccinated cynomolgus macaques infected with (SIV)mac32H(J5): quantitative analysis by in vitro antigenic stimulation.

Detailed analyses of simian immunodeficiency virus (SIV)-specific cytotoxic T lymphocyte (CTL) responses in vaccinated and infected macaques may help to clarify the role of CTL immunity in protection against lentiviruses. Here, the optimal conditions for the measurement of SIV Gag-specific CTL were investigated by bulk and limiting dilution assays of peripheral blood mononuclear cells (PBMC) from naive and vaccinated cynomolgus macaques (Macaca fascicularis) infected with SIVmac32H(J5). In vitro restimulation was generally required for CTL detection. Selective activation of CD8+ and MHC-restricted SIV Gag-specific CTL was induced by stimulation with autologous para-formaldehyde-fixed B-lymphoblastoid cell lines infected with a recombinant vaccinia virus expressing SIV Gag. Applied to limiting dilution assays, antigenic stimulation reproducibly demonstrated SIV Gag-specific CTL precursors (CTLp) in PBMC of all animals studied, including those lacking significant responses in standard bulk CTL assays

MVA-based H5N1 vaccine affords cross-clade protection in mice against influenza A/H5N1 viruses at low doses and after single immunization.

Human infections with highly pathogenic avian influenza viruses of the H5N1 subtype, frequently reported since 2003, result in high morbidity and mortality. It is feared that these viruses become pandemic, therefore the development of safe and effective vaccines is desirable. MVA-based H5N1 vaccines already proved to be effective when two immunizations with high doses were used. Dose-sparing strategies would increase the number of people that can be vaccinated when the amount of vaccine preparations that can be produced is limited. Furthermore, protective immunity is induced ideally after a single immunization. Therefore the minimal requirements for induction of protective immunity with a MVA-based H5N1 vaccine were assessed in mice. To this end, mice were vaccinated once or twice with descending doses of a recombinant MVA expressing the HA gene of influenza virus A/Vietnam/1194/04. The protective efficacy was determined after challenge infection with the homologous clade 1 virus and a heterologous virus derived from clade 2.1, A/Indonesia/5/05 by assessing weight loss, virus replication and histopathological changes. It was concluded that MVA-based vaccines allowed significant dose-sparing and afford cross-clade protection, also after a single immunization, which are favorable properties for an H5N1 vaccine candidate

Optimization and Dose Estimation of Aerosol Delivery to Non-Human Primates

Background: In pre-clinical animal studies, the uniformity of dosing across subjects and routes of administration is a crucial requirement. In preparation for a study in which aerosolized live-attenuated measles virus vaccine was administered to cynomolgus monkeys (Macaca fascicularis) by inhalation, we assessed the percentage of a nebulized dose inhaled under varying conditions. Methods: Drug delivery varies with breathing parameters. Therefore we determined macaque breathing patterns (tidal volume, breathing frequency, and inspiratory to expiratory (I:E) ratio) across a range of 3.3-6.5 kg body weight, using a pediatric pneumotachometer interfaced either with an endotracheal tube or a facemask. Subsequently, these breathing patterns were reproduced using a breathing simulator attached to a filter to collect the inhaled dose. Albuterol was nebulized using a vibrating mesh nebulizer and the percentage inhaled dose was determined by extraction of drug from the filter and subsequent quantification. Results: Tidal volumes ranged from 24 to 46 mL, breathing frequencies from 19 to 31 breaths per minute and I:E ratios from 0.7 to 1.6. A small pediatric resuscitation mask was identified as the best fitting interface between animal and pneumotachometer. The average efficiency of inhaled dose delivery was 32.1% (standard deviation 7.5, range 24%-48%), with variation in tidal volumes as the most important determinant. Conclusions: Studies in non-human primates aimed at comparing aerosol delivery with other routes of administration should take both the inter-subject variation and relatively low efficiency of delivery to these low body weight mammals into account

Comparison of the efficacy of early versus late viral proteins in vaccination against SIV.

The immune response against early regulatory proteins of simian- and human immunodeficiency virus (SIV, HIV) has been associated with a milder course of infection. Here, we directly compared vaccination with Tat/Rev versus Pol/Gag. Challenge infection with SIVmac32H (pJ5) suggested that vaccination with Tat/Rev induced cellular immune responses that enabled cynomolgus macaques to more efficiently control SIV replication than the vaccine-induced immune responses against Pol/Gag. Vaccination with Tat/Rev resulted in reduced plasma SIV loads compared with control (P=0.058) or Pol/Gag-vaccinated (P

Analysis of mouse brain transcriptome after experimental Duvenhage virus infection shows activation of innate immune response and pyroptotic cell death pathway

Rabies is an important neglected disease, characterized by invariably fatal encephalitis. Several studies focus on understanding the pathogenic mechanisms of the prototype lyssavirus rabies virus (RABV) infection, and little is known about the pathogenesis of rabies caused by other lyssaviruses. We sought to characterize the host response to Duvenhage virus infection and compare it with responses observed during RABV infection by gene expression profiling of brains of mice with the respective infections. We found in both infections differentially expressed genes leading to increased expression of type I interferons (IFNs), chemokines, and proinflammatory cytokines. In addition several genes of the IFN signaling pathway are up-regulated, indicating a strong antiviral response and activation of the negative feedback mechanism to limit type I IFN responses. Furthermore we provide evidence that in the absence of significant neuronal apoptotic death, cell death of neurons is mediated via the pyroptotic pathway in both infections. Taken together, we have identified several genes and/or pathways for both infections that could be used to explore novel approaches for intervention strategies against rabies

Optimization and Dose Estimation of Aerosol Delivery to Non-Human Primates

Background: In pre-clinical animal studies, the uniformity of dosing across subjects and routes of administration is a crucial requirement. In preparation for a study in which aerosolized live-attenuated measles virus vaccine was administered to cynomolgus monkeys (Macaca fascicularis) by inhalation, we assessed the percentage of a nebulized dose inhaled under varying conditions. Methods: Drug delivery varies with breathing parameters. Therefore we determined macaque breathing patterns (tidal volume, breathing frequency, and inspiratory to expiratory (I:E) ratio) across a range of 3.3-6.5 kg body weight, using a pediatric pneumotachometer interfaced either with an endotracheal tube or a facemask. Subsequently, these breathing patterns were reproduced using a breathing simulator attached to a filter to collect the inhaled dose. Albuterol was nebulized using a vibrating mesh nebulizer and the percentage inhaled dose was determined by extraction of drug from the filter and subsequent quantification. Results: Tidal volumes ranged from 24 to 46 mL, breathing frequencies from 19 to 31 breaths per minute and I: E ratios from 0.7 to 1.6. A small pediatric resuscitation mask was identified as the best fitting interface between animal and pneumotachometer. The average efficiency of inhaled dose delivery was 32.1% (standard deviation 7.5, range 24%-48%), with variation in tidal volumes as the most important determinant. Conclusions: Studies in non-human primates aimed at comparing aerosol delivery with other routes of administration should take both the inter-subject variation and relatively low efficiency of delivery to these low body weight mammals into account

Decline of simian immunodeficiency virus (SIV)-specific cytotoxic T lymphocytes in the peripheral blood of long-term nonprogressing macaques infected with SIVmac32H-J5.

The evolution of simian immunodeficiency virus (SIV)–specific cytotoxic T lymphocyte precursors (CTLps) and their relationship with virus replication were studied in SIV‐infected macaques. After primary viremia, 3 of 8 macaques l