Elemental analysis of lung tissue particles and intracellular iron content of alveolar macrophages in pulmonary alveolar proteinosis

Abstract

BackgroundPulmonary alveolar proteinosis (PAP) is a rare disease occurred by idiopathic (autoimmune) or secondary to particle inhalation. The in-air microparticle induced X-ray emission (in-air micro-PIXE) system performs elemental analysis of materials by irradiation with a proton microbeam, and allows visualization of the spatial distribution and quantitation of various elements with very low background noise. The aim of this study was to assess the secondary PAP due to inhalation of harmful particles by employing in-air micro-PIXE analysis for particles and intracellular iron in parafin-embedded lung tissue specimens obtained from a PAP patient comparing with normal lung tissue from a non-PAP patient. The iron inside alveolar macrophages was stained with Berlin blue, and its distribution was compared with that on micro-PIXE images.ResultsThe elements composing particles and their locations in the PAP specimens could be identified by in-air micro-PIXE analysis, with magnesium (Mg), aluminum (Al), silicon (Si), phosphorus (P), sulfur (S), scandium (Sc), potassium (K), calcium (Ca), titanium (Ti), chromium (Cr), copper (Cu), manganase (Mn), iron (Fe), and zinc (Zn) being detected. Si was the major component of the particles. Serial sections stained by Berlin blue revealed accumulation of sideromacrophages that had phagocytosed the particles. The intracellular iron content of alveolar macrophage from the surfactant-rich area in PAP was higher than normal lung tissue in control lung by both in-air micro-PIXE analysis and Berlin blue staining.ConclusionThe present study demonstrated the efficacy of in-air micro-PIXE for analyzing the distribution and composition of lung particles. The intracellular iron content of single cells was determined by simultaneous two-dimensional and elemental analysis of paraffin-embedded lung tissue sections. The results suggest that secondary PAP is associated with exposure to inhaled particles and accumulation of iron in alveolar macrophages.

The interaction of asbestos and iron in lung tissue revealed by synchrotron-based scanning X-ray microscopy

“…Indeed, the S and P distributions measured by XRF have already been used as indicators of cellular components, in cell samples34 and, with a similar technique (PIXE) but at lower lateral resolution, also in human lung tissue sections35. In our study the spatial resolution provided, confirms that probing the distribution of these two elements can be employed for investigating in detail the cellular mechanism in unstained tissues.…”

Diagnostic and Therapeutic Approach for Acute Paraquat Intoxication

“…The primary use of chelating has been via iron overload transfusion ( 54 ). However, coupled with advances in tissue iron quantitation ( 55 , 56 ), there is tremendous promise of an individually tailored approach to chelating, and subsequent reduction in morbidity and mortality. With this background, appropriate iron chelating would be an effective treatment modality in patients with acute PQ intoxication.…”

Development of microbeam technology to expand applications at TIARA

“…Therefore, for service inside the vacuum, we developed a target stage that includes a rotation stage [21]. Now with the ordinary system, biomedical applications are more practical; for example, the analysis of erythrocyte elements in chronic hepatitis C patients treated with interferon and ribavirin [22], elemental analysis of lung-tissue particles and intracellular iron content of alveolar macrophages in pulmonary alveolar proteinosis [23] and fluorine analysis of human enamel around fluoride-containing materials under different pH cycling [24]. This system was also used to develop materials for Li-ion batteries, in particular, to obtain the distribution of Li in the electrode by means of particle-induced c-ray emission (PIGE) and nuclear-reaction analysis (NRA) combined with micro-PIXE [25].…”