Pathophysiological Studies of Chronic Pseudomonas aeruginosa Lung Infection in Mice Treated with Aerosolized RTD-1. Chronic infection was established via intratracheal instillation of 5 × 105 CFUs of P. aeruginosa (RP73, mucoid CF isolate). Aerosolized RTD-1 at a dose of 167 mg/kg commenced 24 h after infection and continued for 6 days. Effects of treatment on: (A) lung bacterial burden, (B) total immune cell counts, (C) weight, and (D) differential cell counts were evaluated (** p ≤ 0.01, *** p ≤ 0.001). BALF, bronchoalveolar lavage fluid; CFU, colony forming unit; PMN, polymorphonuclear leukocyte; WBC, white blood cell.