Localization of aspirated Asian sand dust corresponding with early inflammatory response in the lung using Raman...

The relationship between the behavior of inhaled particulate matter and the inflammatory response in the lungs is not clear. In the present study, we investigated the localization of Asian sand dust (ASD) particles intratracheally instilled into the lungs and the responded activation of NF-κB.

One hour after intratracheal ASD administration, quantitative analysis of NF-κB in the nuclei of lung tissues, translocation of NF-κB protein, and ASD localization were examined by enzyme-linked immunosorbent assay, immunohistochemistry (bright field), dark field observation, and Raman technique.

ASD exposure induced the nuclear translocation of NF-κB in type II alveolar epithelial cells, alveolar macrophages, and neutrophils within the alveolar wall. Dark field observation and Raman analyses revealed that the ASD components Fe₂O₃, TiO₂, and SiO₂ were detected in or near these cells in which immunoreactive NF-κB was present.

These results indicate that this combined technique, which takes advantage of Raman spectroscopy, may better evaluate the spatial relationship between the localization of particulate matter and the organ's early inflammatory response.