NanoCOLT-Modulatory effects of modified carbon black nanoparticles in a mouse model of allergic asthma

Rationale: Nanoparticles in form of industrial carbon black nanoparticles (CBNP) are the most commonly produced nanoparticles worldwide. CBNP can get into the lung via inhalation and may present a potential health risk. Recent studies showed that exposure of nanoparticles can trigger acute asthma exacerbation that lead to enhanced inflammation and mucus production. However, until yet, it is unknown, whether the risk potential arises directly or indirectly from the surface of the CBNP. Thus, the aim of this study was to investigate the modulatory effects of different modified and well-characterized CBNP in a mouse model of allergic asthma.

Methods: To induce an acute experimental asthma, wild-type mice were sensitized to ovalbumin (OVA) and challenged with an OVA aerosol on three consecutive days. The CBNP were applied by oropharyngeal aspiration prior the third challenge and 24 hours later. The impact of CBNP on distal airways was assessed by microdissection. Cytokine mRNA expression was analyzed by qPCR and cytokine levels by CBA. Airway hyperresponsiveness (AHR) was determined by using the Buxco FinePoint RC System.

Results: In mice with acute experimental allergic asthma we showed that repetitive low-dose aspiration of different modified CBNP neither affect the airway reagibility, the infiltration of leukocytes into the airways nor the mRNA expression of pro-inflammatory cytokines in the distal airways compared to the vehicle-exposed mice.

Conclusion: Although our results do not show significant pro-inflammatory effects of the modified CBNP on distal airways and on lung function, it cannot be ruled out that proliferation or apoptosis of airway cells are affected by CBNP. We also intend to test the toxic long-term effects of different surface modifications of the CBNP.

Supported by the BMBF (FKZ: 03X0153B)