Pulmonary inflammation induced by office dust and the relation to 1 → 3-β-glucan using different extraction techniques

Abstract

It is observed that 1 → 3-β-glucan, a major cell wall component of fungi, induces pulmonary inflammation. There is inconsistency in determining the correlation between the levels of glucan measured by current extraction methods and the respiratory inflammation observed in individuals or lab animals exposed to environmental dust samples. The glucan-specific limulus amebocyte lysate (G-LAL) method was used after extraction with dimethyl sulfoxide (DMSO) or sodium hydroxide (NaOH) to analyze the glucan content of office dust samples collected from a water-damaged building. C3HeB/FeJ mice, an endotoxin-sensitive strain, were treated with different dust samples (2.5 mg kg⁻¹ body weight) or saline (vehicle control) by pharyngeal aspiration. At 1 day after aspiration, bronchoalveolar lavage (BAL) was performed, and lung inflammation and injury were assessed by measuring: (1) neutrophil (PMN) infiltration, (2) inflammatory cytokine (IL-6, IL-10, MCP-1, IFN-γ, TNF-α, and IL12-p70) levels, and (3) albumin and lactate dehydrogenase in recovered BAL fluid. Both DMSO and NaOH extraction increased the detection of glucan by approximately 20-fold compared to water extraction. However, only the DMSO extraction method showed a statistically significant positive correlation between 1 → 3-β-glucan and albumin levels, total numbers of BAL, polymorphonuclear leukocytes (PMNs) cells recovered, levels of TNF-α, MCP-1, and IL-6. In conclusion, 1 → 3-β-glucan is a potent inflammatory agent in dust samples and DMSO extraction for glucan analysis may prove useful in understanding the impact of environmental contamination by glucans on lung disease.

Keywords:

• dusts analysis
• cytokines
• endotoxins
• sick building syndrome
• 1 → 3-β-glucans
• lung inflammation
• animal studies