E-cigarettes are increasingly popular, but even though they are generally considered less harmful than conventional cigarettes, they are not risk-free. To minimize the health risks for consumers, emissions must be analyzed and toxicologically assessed. However, although guidelines exist on how to puff e-cigarettes for analysis, neither operational settings of the devices are defined nor the devices themselves. Therefore, generated emissions differ substantially. As e-liquids contain heat-labile substances, it is essential to analyze their emissions at all temperatures which can be met during usage of any type of e-cigarette. A new device is presented allowing the vaporization of e-liquids in the relevant temperature range under controllable and reproducible conditions. The aerosol collected mass was measured to demonstrate the method's reproducibility. Temperature curves show the effectiveness of the PID controller in regulating temperature. To prove the relevance of the presented device, two flavor mixtures were vaporized and emissions were analyzed by GC-MS showing temperature dependent changes. Furthermore, for one e-liquid, it was shown that generated emissions were comparable to those generated in an e-cigarette proving that the device operates under real-world vaping conditions. Therefore, the presented device is a valuable tool to improve toxicological assessments and thus increase consumer safety.

Introduction: To determine threshold concentrations of pollen inducing symptoms in seasonal allergic rhinitis patients has been a challenge for decades. Allergen challenge chambers (ACC) allow a controlled, reproducible experimental design to address this problem. Hitherto, ACCs were only run with high pollen concentrations. METHODS:The Fraunhofer ACC was technically modified to deploy very low pollen concentrations. Then, adults with birch pollen-induced allergic rhinitis were challenged with varying birch pollen concentrations using a patient-blinded, sham challenge-controlled, part-randomized, titrate-to-effect clinical study setting. Mean increase in Total Nasal Symptom Score (TNSS) ≥0.55 compared to sham challenge was regarded as minimal clinically important difference (MCID). Further endpoints were nasal secretion weight, exhaled nitric oxide (FeNO), and inflammatory cells from nasal lavage. RESULTS:Fifteen participants with mild to moderate allergic rhinitis participated in the experimental study part (mean age 45 years [22-64]; 7 females). Mean TNSS was: 1.08 at 0 pollen/m3; 1.05 at 10 pollen/m3; 1.2 at 50 pollen/m3; 1.74 at 100 pollen/m3; 1.61 at 200 pollen/m3; 2.79 at 1,000 pollen/m3. MCID of TNSS was observed at 100, 200, and 1,000 pollen/m3. More than half of the study population showed a lack of response at 10, 50, and 200 pollen/m3. Nasal secretion increased slightly with concentration. No clinically meaningful results could be derived from FeNO and inflammatory cells. CONCLUSIONS:The applied technical modification of the Fraunhofer ACC produced stable, low pollen concentrations. Based on mean TNSS data, the threshold concentration for inducing symptoms with birch pollen was 50-100 pollen/m3. .

Background Extensive analysis of eosinophilic airway inflammation in human-relevant animal models is required to test novel, human-specific pharmaceuticals. This requires species, which show high genetic homology to humans such as non-human primates. Efficacy assessment of novel human-specific biologicals in eosinophilic airway inflammation is currently performed in the cost-intensive macaque asthma model.Objective The present study investigated whether marmoset monkeys ( Callithrix jacchus ), a small-bodied non-human primate species from the New World, develop eosinophilic airway inflammation in response to house dust mite allergen exposure (HDM, Dermatophagoides pteronyssinus ).Methods Marmoset monkeys were sensitized against HDM by subcutaneous (s.c.) injection and subsequent intratracheal (i.t.) HDM aerosol challenges. Airway and systemic immunologic reactions were monitored and sensitivity towards glucocorticoid therapy was assessed. The pulmonary immunologic response was analyzed by repetitive bronchoalveolar lavage (BAL).Results Bronchoalveolar lavage fluid (BALF) exhibited increased levels of eosinophils, mast cells, and lymphocytes, as well as interleukin (IL)-13 after HDM challenges, compared to negative controls. The systemic immunologic response was assessed in peripheral blood mononuclear cells derived from sensitized animals, which secreted increased IL-13 and IFN-γ upon allergen stimulation in contrast to non-sensitized negative control animals. Although IgE was not detectable, HDM-specific serum IgG was elevated in sensitized animals. Both airway and systemic responses were reduced by treatment with glucocorticoids. However, lung function and pathological analyses did not reveal significant differences between groups.Conclusion In conclusion, marmoset monkeys developed a mild HDM-induced eosinophilic airway inflammation useful for efficacy testing of novel human-specific biologicals.

ABSTRACT Increased adverse health effects in older subjects due to exposure to ambient air pollutants may be related to the inflammatory response induced by these contaminants. The aim of this study was to assess airway and systemic inflammatory responses in older healthy subjects to a controlled experimental exposure with spark-generated elemental carbon black ultrafine particles (cbUFPs) and ozone (O3). Twenty healthy subjects, age 52–75 years, were exposed on three occasions separated by at least 8 weeks. The exposures to filtered air (FA), to cbUFP (50 μg/m3), or to cbUFP in combination with 250 ppb ozone (cbUFP + O3) for 3 h with intermittent exercise were performed double blind, and in random order. Sputum and blood samples were collected 3.5 h after each exposure. Exposure to cbUFP + O3 significantly increased plasma club cell protein 16 (CC16), the number of sputum cells, the number and percent of sputum neutrophils, and sputum interleukin 6 and matrix metalloproteinase 9. Exposure to cbUFP alone exerted no marked effect, except for an elevation in sputum neutrophils in a subgroup of 13 subjects that displayed less than 65% sputum neutrophils after FA exposure. None of the inflammatory markers was correlated with age, and serum cardiovascular risk markers were not markedly affected by cbUFP or cbUFP + O3. Exposure to cbUFP+O3 induced a significant airway and systemic inflammatory response in older healthy volunteer subjects. The effects induced by cbUFP alone suggest that the inflammation was predominantly mediated by O3, although one cannot rule out that the interaction of cbUFP and O3 played a role.

Efficacy testing of immunotherapy in field studies is often hampered by variation of airborne allergens. Standardized allergen exposure in challenge chamber settings might be an alternative. Therefore, we developed a universal technique to create an atmosphere loaded with allergen particles of adjustable size from aqueous solutions of licensed allergen extracts.

Epidemiological and experimental studies suggest that exposure to ultrafine particles (UFP) might aggravate the allergic inflammation of the lung in asthmatics.

Introduction: Similar to the established rodents models, new translational nonhuman primate models in marmoset monkeys (Callitrix jacchus) require data about lung function. In order to gain physiological and pathological baseline data, we tested our hypotheses, that A) animals develop airway hyperresponsiveness (AHR) after pulmonary LPS-challenge and B) house-dust-mite (HDM) allergen sensitized individuals show AHR after allergen challenge.

Animal models with a high predictive value for human trials are needed to develop novel human-specific therapeutics for respiratory diseases. The aim of the present study was to examine lung-function parameters in marmoset monkeys (Callithrix jacchus) that can be used to detect pharmacologically or provocation-induced AHR (airway hyper-responsiveness). Therefore a custom-made lung-function device that allows application of defined aerosol doses during measurement was developed. It was hypothesized that LPS (lipopolysaccharide)-challenged marmosets show AHR compared with non-challenged healthy subjects. Invasive plethysmography was performed in 12 anaesthetized orotracheally intubated and spontaneously breathing marmosets. Pulmonary data of R(L) (lung resistance), C(dyn) (dynamic compliance), EF50 (mid-expiratory flow), P(oes) (oesophageal pressure), MV (minute volume), respiratory frequency (f) and V(T) (tidal volume) were collected. Measurements were conducted under baseline conditions and under MCh (methacholine)-induced bronchoconstriction. The measurement was repeated with the same group of animals after induction of an acute lung inflammation by intratracheal application of LPS. PDs (provocative doses) of MCh to achieve a certain increase in RL were significantly lower after LPS administration. AHR was demonstrated in the LPS treated compared with the naïve animals. The recorded lung-function data provide ground for pre-clinical efficacy and safety testing of anti-inflammatory substances in the common marmoset, a new translational NHP (non-human primate) model for LPS-induced lung inflammation.

BACKGROUNDHuman breath contains small particles that might be useful for the noninvasive diagnosis of lung disease. In this study, the impact of airway obstruction on particle emission was investigated.METHODSParticle number flux and particle size distribution were measured for healthy nonsmokers (n=16), healthy smokers (n=13), patients with chronic obstructive pulmonary disease (n=28, GOLD stage I-IV), and patients with asthma before and after methacholine challenge (n=10). The measurements were carried out using a condensation nucleus counter (TSI 3760) and a laser spectrometer (PMT LASAIR II-110).RESULTSParticle number per breath showed high intrasubject reproducibility. However, there was a large intersubject variability in the number of emitted particles on the order of two magnitudes, with no influence of airway obstruction on emission level. Methacholine-induced airway obstruction, in subjects with allergic asthma, did not change the number of exhaled particles, when compared with prechallenge values. For the droplet size distribution averaged per breath, there was no difference between healthy subjects and subjects with airway obstruction.CONCLUSIONSAirway obstruction does not change the number flux or size distribution of particles in exhaled breath. The high intersubject variability of particle emission supports the concept of online determination of aerosol properties (primarily number flux, during exhaled breath) during breath condensate sampling to properly normalize the results of biochemical analysis. As high dilution and variable dilution are the main challenges of biomarker assessment in exhaled breath condensate, this normalization procedure would significantly add to the value of the technique.

This article was originally published online on 03 February 2014 Efficacy testing of immunotherapy in field studies is often hampered by variation of airborne allergens. Standardized allergen exposure in challenge chamber settings might overcome aforementioned limitations. However, airborne allergens such as house dust mite (HDM) or cat allergen are not available as standardized source material with distinct particle size. Therefore, we developed a method for universal allergen particle generation and conducted a pilot study to clinically validate this challenge paradigm for house dust mite. House dust mite allergen extract (ALK lyophilised SQ503 Der p, ALK-Abello, Wedel, Germany) was diluted in an aqueous solution of 10% lactose. The solution was spray-dried at various liquid feed rates leading to allergen aerosols with different pre-defined concentrations but a constant mass mean aerodynamic particle diameter of 13.5 µm. Particle size is dependent on the solute (lactose) concentration and can thereby be adjusted accordingly. In a single-blind, five-way cross-over pilot study 18 subjects with allergic rhinitis and sensitization to HDM were allergen-exposed for 4 hours at either 250 SQE/m3, 500 SQE/m3, 1000 SQE/m3, or lactose alone (0 SQE/m3) seven days apart. The dose of 500 SQE/m3 was repeated to investigate reproducibility. Total nasal symptom score (TNSS), anterior rhinomanometry, nasal secretions, exhaled NO, FEV1, and adverse events were assessed prior to and during the exposures. Allergen exposure was safe and significantly elicited symptoms of AR compared to room air exposure with a mean total nasal symptom score (TNSS) of 3.6±2.0 (mean±SD) at the highest allergen concentration. Lactose alone did not change TNSS (0.7±0.6) compared to pre-challenge level. Repeated exposure to 500 SQE/m3 induced a TNSS which was not different between the two challenge sessions. Objective measures of nasal flow and nasal secretions were in line with clinical symptoms. We conclude that this universal allergen particle generation is safe, specific, and reproducible and can therefore be used for efficacy testing of immunotherapy.