A Nose-Only Inhalation Exposure System For The Delivery Of Dry Fungal Spores (Aspergillus Fumigatus)

ABSTRACTIn the indoor environment, people are exposed to several fungal species. Evident dampness is associated with increased respiratory symptoms. To examine the immune responses associated with fungal exposure, mice are often exposed to a single species grown on an agar medium. The aim of this study was to develop an inhalation exposure system to be able to examine responses in mice exposed to mixed fungal species aerosolized from fungus-infested building materials. Indoor airborne fungi were sampled and cultivated on gypsum boards. Aerosols were characterized and compared with aerosols in homes. Aerosols containing 107CFU of fungi/m3air were generated repeatedly from fungus-infested gypsum boards in a mouse exposure chamber. Aerosols containedAspergillus nidulans,Aspergillus niger,Aspergillus ustus,Aspergillus versicolor,Chaetomium globosum,Cladosporiumherbarum,Penicillium brevicompactum,Penicillium camemberti,Penicillium chrysogenum,Penicillium commune,Penicillium glabrum,Penicillium olsonii,Penicillium rugulosum,Stachybotrys chartarum, andWallemia sebi. They were all among the most abundant airborne species identified in 28 homes. Nine species from gypsum boards and 11 species in the homes are associated with water damage. Most fungi were present as single spores, but chains and clusters of different species and fragments were also present. The variation in exposure level during the 60 min of aerosol generation was similar to the variation measured in homes. Through aerosolization of fungi from the indoor environment, cultured on gypsum boards, it was possible to generate realistic aerosols in terms of species composition, concentration, and particle sizes. The inhalation-exposure system can be used to study responses to indoor fungi associated with water damage and the importance of fungal species composition.

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An Inhalation Exposure System for the Oil Dispersant COREXIT® EC9500A

The FASEB Journal ◽

10.1096/fasebj.25.1_supplement.1016.1 ◽

2011 ◽

Vol 25 (S1) ◽

Author(s):

William Travis Goldsmith ◽

Walter McKinney ◽

Mark Jackson ◽

Brandon Law ◽

Toni Bledsoe ◽

...

Keyword(s):

Inhalation Exposure ◽

Exposure System ◽

Oil Dispersant

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Optimization of the Vitrocell 24/48 in vitro inhalation exposure system for nanoparticles

Toxicology Letters ◽

10.1016/j.toxlet.2018.06.546 ◽

2018 ◽

Vol 295 ◽

pp. S79

Author(s):

E. Frijns ◽

J. Van Laer ◽

A. Jacobs ◽

S. Verstraelen

Keyword(s):

Inhalation Exposure ◽

Exposure System

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Development, Characterization, and Standardization of a Nose-Only Inhalation Exposure System for Exposure of Rabbits to Small-Particle Aerosols ContainingFrancisella tularensis

Infection and Immunity ◽

10.1128/iai.00198-19 ◽

2019 ◽

Vol 87 (8) ◽

Cited By ~ 4

Author(s):

Katherine J. O’Malley ◽

Jennifer D. Bowling ◽

Eileen M. Barry ◽

Karsten R. O. Hazlett ◽

Douglas S. Reed

Keyword(s):

Weight Loss ◽

Median Survival ◽

Bacterial Culture ◽

Severe Disease ◽

Inhalation Exposure ◽

Brain Heart Infusion ◽

Survival Times ◽

Exposure System ◽

Content Type ◽

Schu S4

ABSTRACTInhalation ofFrancisella tularensiscauses pneumonic tularemia in humans, a severe disease with a 30 to 60% mortality rate. The reproducible delivery of aerosolized virulent bacteria in relevant animal models is essential for evaluating medical countermeasures. Here we developed optimized protocols for infecting New Zealand White (NZW) rabbits with aerosols containingF. tularensis. We evaluated the relative humidity, aerosol exposure technique, and bacterial culture conditions to optimize the spray factor (SF), a central metric of aerosolization. This optimization reduced both inter- and intraday variability and was applicable to multiple isolates ofF. tularensis. Further improvements in the accuracy and precision of the inhaled pathogen dose were achieved through enhanced correlation of the bacterial culture optical density and the number of CFU. Plethysmograph data collected during exposures found that respiratory function varied considerably between rabbits, was not a function of weight, and did not improve with acclimation to the system. Live vaccine strain (LVS)-vaccinated rabbits were challenged via aerosol with human-virulentF. tularensisSCHU S4 that had been cultivated in either Mueller-Hinton broth (MHB) or brain heart infusion (BHI) broth. LVS-vaccinated animals challenged with SCHU S4 that had been cultivated in MHB experienced short febrile periods (median, 3.2 days), limited weight loss (<5%), and longer median survival times (∼18 days) that were significantly different from those for unvaccinated controls. In contrast, LVS-vaccinated rabbits challenged with SCHU S4 that had been cultivated in BHI experienced longer febrile periods (median, 5.5 days) and greater weight loss (>10%) than the unvaccinated controls and median survival times that were not significantly different from those for the unvaccinated controls. These studies highlight the importance of careful characterization and optimization of protocols for aerosol challenge with pathogenic agents.

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Influence of Aspergillus fumigatus conidia viability on murine pulmonary microRNA and mRNA expression following subchronic inhalation exposure

Clinical & Experimental Allergy ◽

10.1111/cea.12783 ◽

2016 ◽

Vol 46 (10) ◽

pp. 1315-1327 ◽

Cited By ~ 24

Author(s):

T. L. Croston ◽

A. P. Nayak ◽

A. R. Lemons ◽

W. T. Goldsmith ◽

J. K. Gu ◽

...

Keyword(s):

Aspergillus Fumigatus ◽

Mrna Expression ◽

Inhalation Exposure

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Disinfection of selected Aspergillus spp. using ultraviolet germicidal irradiation

Canadian Journal of Microbiology ◽

10.1139/w04-002 ◽

2004 ◽

Vol 50 (3) ◽

pp. 221-224 ◽

Cited By ~ 15

Author(s):

Christopher F Green ◽

Pasquale V Scarpino ◽

Paul Jensen ◽

Nancy J Jensen ◽

Shawn G Gibbs

Keyword(s):

Aspergillus Fumigatus ◽

Aspergillus Flavus ◽

Fungal Spores ◽

Petri Dish ◽

Testing Unit ◽

Ultraviolet Germicidal Irradiation ◽

Airborne Fungal Spores ◽

Agar Surface ◽

Petri Dishes ◽

Higher Doses

Aims: The efficacy of ultraviolet germicidal irradiation (UVGI) and the UVGI dose necessary to inactivate fungal spores on an agar surface for cultures of Aspergillus flavus and Aspergillus fumigatus were determined. Methods and results: A four-chambered UVGI testing unit with a 9-W, Phillips, low pressure, mercury UVGI lamp in each chamber was used in this study. An aperture was adjusted to provide 50, 100, 150, and 200 µW/cm2 of uniform flux to the surfaces of the Petri dish, resulting in a total UVGI dose to the surface of the Petri dishes ranging from 12 to 96 mJ/cm2. The UVGI dose necessary to inactivate 90% of the A. flavus and A. fumigatus was 35 and 54 mJ/cm2, respectively. Conclusions: UVGI can be used to inactivate culturable fungal spores. Aspergillus flavus was more susceptible than A. fumigatus to UVGI. Significance and impact of the study: These results may not be directly correlated to the effect of UVGI on airborne fungal spores, but they indicate that current technology may not be efficacious as a supplement to ventilation unless it can provide higher doses of UVGI to kill spores traveling through the irradiated zone.Key words: Aspergillus, ultraviolet germicidal irradiation, fungi.

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