Influence of cefodizime on pulmonary inflammatory response to heat-killed Klebsiella pneumoniae in mice

Encapsulated Klebsiella pneumoniae strains frequently induce fatal nosocomi al pneumonia. Cefodizime (CEF) as an antibiotic is suspected to enhance hos t resistance against various microbial invasions through interactions with bacteria and host cells. To investigate the influence of CEF on the pulmona ry response to Klebsiella that does not merely result from direct bacterial clearance by the drug, we inoculated mice with heat-killed fluorescein iso thiocyanate-labeled K: pneumoniae. CEF upregulated (P < 0.01) the early Kle bsiella-induced secretion of tumor necrosis factor alpha, as well as the nu mber (P < 0.01) and phagocytic efficacy (P < 0.001) of alveolar macrophages . By contrast, the late polymorphonuclear neutrophil recruitment (P < 0.05) and levels of interleukin-1 alpha (IL-1 alpha) (P < 0.05) and IL-6 (P < 0. 05) were reduced. The stimulation of an early immune response by CEF follow ed by late reduction in inflammation may be beneficial against bacterial pn eumonia.