Dataset Information

Pulmonary challenge with carbon nanoparticles induces a dose-dependent increase in circulating leukocytes in healthy males.

ABSTRACT:

Background

Inhalation of particulate matter, as part of air pollution, is associated with increased morbidity and mortality. Nanoparticles (< 100 nm) are likely candidates for triggering inflammatory responses and activation of coagulation pathways because of their ability to enter lung cells and pass bronchial mucosa. We tested the hypothesis that bronchial segmental instillation of carbon nanoparticles causes inflammation and activation of coagulation pathways in healthy humans in vivo.

Methods

This was an investigator-initiated, randomized controlled, dose-escalation study in 26 healthy males. Participants received saline (control) in one lung segment and saline (placebo) or carbon nanoparticles 10 ?g, 50 ?g, or 100 ?g in the contra-lateral lung. Six hours later, blood and bronchoalveolar lavage fluid (BALF) was collected for inflammation and coagulation parameters.

Results

There was a significant dose-dependent increase in blood neutrophils (p = 0.046) after challenge with carbon nanoparticles. The individual top-dose of 100 ?g showed a significant (p = 0.05) increase in terms of percentage neutrophils in blood as compared to placebo.

Conclusions

This study shows a dose-dependent effect of bronchial segmental challenge with carbon nanoparticles on circulating neutrophils of healthy volunteers. This suggests that nanoparticles in the respiratory tract induce systemic inflammation.

Trial registration

Dutch Trial Register no. 2976. 11 July 2011. http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2976.

SUBMITTER: Berger M

PROVIDER: S-EPMC5588713 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Publications

Pulmonary challenge with carbon nanoparticles induces a dose-dependent increase in circulating leukocytes in healthy males.

Berger Marieke M de Boer Johannes D JD Lutter René R Makkee Michiel M Sterk Peter J PJ Kemper Elles M EM van der Zee Jaring S JS

BMC pulmonary medicine 20170906 1

<h4>Background</h4>Inhalation of particulate matter, as part of air pollution, is associated with increased morbidity and mortality. Nanoparticles (< 100 nm) are likely candidates for triggering inflammatory responses and activation of coagulation pathways because of their ability to enter lung cells and pass bronchial mucosa. We tested the hypothesis that bronchial segmental instillation of carbon nanoparticles causes inflammation and activation of coagulation pathways in healthy humans in vivo ...[more]

PMID: 28877711

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Dataset Information

Pulmonary challenge with carbon nanoparticles induces a dose-dependent increase in circulating leukocytes in healthy males.

Background

Methods

Results

Conclusions

Trial registration

Publications

Pulmonary challenge with carbon nanoparticles induces a dose-dependent increase in circulating leukocytes in healthy males.

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