Pseudomonas aeruginosa exoenzyme S induces transcriptional expression of proinflammatory cytokines and chemokines.

Pseudomonas aeruginosa infection of cystic fibrosis patients causes lung damage that is substantially orchestrated by cytokines. In this study, multi-gene probe analysis was used to characterize the ability of the P. aeruginosa mitogen, exoenzyme S, to induce proinflammatory and immunoregulatory cytokines and chemokines. Exoenzyme S strongly induced transcription of proinflammatory cytokines and chemokines (tumor necrosis factor alpha, interleukin-1alpha [IL-1alpha], IL-1beta, IL-6, IL-8, MIP-1alpha, MIP-1beta, MCP-1, RANTES, and I-309), modest transcription of immunoregulatory cytokines (IL-10 and IL-12p40), and weak transcription of Th1 cytokines (IL-2 and gamma interferon). The response occurred early and subsided without evolving over time. These data suggest that cells responding to exoenzyme S would rapidly express proinflammatory cytokines and chemokines that may contribute to pulmonary inflammation in cystic fibrosis.