title: Clarithromycin and prednisolone inhibit cytokine production in chronic rhinosinusitis.
abstract: OBJECTIVE
  Long-term, low-dose macrolide therapy is effective in the treatment of chronic rhinosinusitis. The mechanism of its anti-inflammatory effect and how this differs from corticosteroids remains unclear. The effect of clarithromycin and prednisolone on interleukin-5, interleukin-8, and granulocyte-macrophage colony-stimulating factor production by cultured chronic sinusitis nasal mucosa was examined in the study.
  
  
  METHODS
  Nasal mucosa was obtained from 11 patients with chronic sinusitis. This tissue was cultured for 24 hours in the presence of clarithromycin or prednisolone at a variety of concentrations. Cytokine levels were determined by enzyme-linked immunoassay.
  
  
  RESULTS
  Clarithromycin and prednisolone each produced significant reductions in interleukin-5, interleukin-8, and granulocyte-macrophage colony-stimulating factor production. There was no significant difference between the effects of clarithromycin and prednisolone.
  
  
  CONCLUSIONS
  Macrolide antibiotics are capable of inhibiting pro-inflammatory cytokine production in vitro and are as potent as prednisolone. This mechanism is likely to be at least partly responsible for the clinical efficacy of macrolide antibiotics in chronic rhinosinusitis.
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D002908:Chronic Disease; D017291:Clarithromycin / Q000494:pharmacology*; D046508:Culture Techniques; D016207:Cytokines / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005938:Glucocorticoids / Q000494:pharmacology*; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism; D006801:Humans; D015848:Interleukin-5 / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000378:metabolism*; D011239:Prednisolone / Q000494:pharmacology*; D012220:Rhinitis / Q000378:metabolism*; D012852:Sinusitis / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D000893:Anti-Inflammatory Agents; D016207:Cytokines; D005938:Glucocorticoids; D015848:Interleukin-5; D016209:Interleukin-8; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D011239:Prednisolone; D017291:Clarithromycin