Grain Dust Induced Lung Inflammation Is Reduced by 'Rhodobacter sphaeroides'Diphosphoryl Lipid A

摘要

The efficacy of pentaacylated diphosphoryl-lipid-A derived from thelipopolysaccharide (LPS) of Rhodobacter-spheroides (RsDPLA) was examined as a competitive inhibitor of grain dust induced airway inflammation. TTHP-1 cells were incubated with RsDPLA, LPS, or cotton dust extract (CDE). Incubation with LPS or CDE resulted in TNF-alpha release at 0.02 microgram/milliliter. Pretreatment of THP-1 cells with varying concentrations of RsDPLA prior to incubation with LPS or CDE resulted ina dose dependent reduction in the LPS or CDE induced tumor necrosis factor alpha (TNF-alpha) release. The unique LPS inhibitory property of RsDPLA was used to determine the inflammatory response to inhaled CDE in mice in the presence of RsDPLA. No significant inflammatory response was caused by 10 micrograms of RsDPLA intratracheally in comparison to intratracheal saline. Pretreatment with RsDPLA intratracheally prior to exposure to CDE or LPS resulted in significant reductions in the lung lavage concentrations of total cells, neutrophils, TNF-alpha, and interleukin-6 compared to mice pretreated with sterile saline. The authors conclude the LPS inhibitory effect of RsDPLA is confirmed.