Quantification of regional aerosol deposition patterns as a function of aerodynamic particle size in rhesus macaques using PET/CT imaging

Abstract

Aerosol aerodynamic particle size is known to affect deposition patterns of inhaled aerosol particles, as well as the virulence of inhaled bioaerosol particles. While a significant amount of work has been performed to describe the deposition of aerosol particles in the human respiratory tract, only a limited amount of work has been performed to describe the deposition of aerosol particles in the respiratory tract of nonhuman primates, an animal model commonly utilized in pharmacological and toxicological studies, especially in the biodefense field. In this study, anesthetized rhesus macaques inhaled radiolabeled aerosols with MMADs of 1.7, 3.6, 7.4 and 11.8 µm to characterize regional deposition patterns. The results demonstrate that the regional deposition pattern shifts as particle size increases, with greater deposition in more proximal regions of the respiratory tract and decreased deposition in the pulmonary region. The results of this study extend the findings of previous studies which demonstrated a similar shift in the deposition pattern as a function of particle size by providing greater resolution of deposition patterns. These data on regional deposition patterns provide a starting point to begin to explore potential mechanisms responsible for the differences in virulence of infectious bioaerosols as a function of particle size and deposition pattern reported in previous studies. Additionally, the data are useful to assess the performance of various deposition models that have been published in the literature.

Keywords:

• Aerosol deposition
• regional deposition
• particle size
• nonhuman primate
• rhesus macaque
• inhalation
• bioaerosol

Disclosure statement

The authors report no declarations of interest.

Additional information

Funding

This work was partially funded under Contract No. HSHQDC-15-C-00064 awarded to Battelle National Biodefense Institute by the Department of Homeland Security (DHS) Science and Technology Directorate (S&T) for the operation and management of the National Biodefense Analysis and Countermeasures Center a Federally Funded Research and Development Center. The views and conclusions contained in this document are those of the authors and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the DHS or the US Government. DHS does not endorse any products or commercial services mentioned in this presentation.This project has been funded in whole or in part with federal funds from the National Cancer Institute, National Institutes of Health, under Contract No. HHSN261200800001E. The content of the is publication does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the US Government.