Immunomodulating effects of HMR 3004 on pulmonary inflammation caused by heat-killed Streptococcus pneumoniae in mice

We investigated the influence of HMR 3004, a new ketolide antibiotic, on th e pulmonary inflammation induced by beat-killed fluorescein isothiocyanate- labeled Streptococcus pneumoniae. HMR 3004 downregulated (P < 0.05) the pne umococcus-induced release of interleukin-6 (IL-6), IL-1 beta, and nitric ox ide in bronchoalveolar lavage fluid. The drug limited (P < 0.05) neutrophil recruitment to lung tissues and alveoli but did not interfere with phagocy tosis. HMR 3004 totally abrogated lung edema. By reducing inflammation in a ddition to possessing antimicrobial properties, HMR 3004 may participate in improving the outcome of bacterial pneumonia.