title: Effect of N-acetyl-L-cysteine on Cytokine Production by Human Peripheral Blood Mononuclear Cells.
abstract: OBJECTIVE
  This study investigates the in vitro effect of the antioxidant drug, N-acetyl-L-cysteine (NAC), on cytokine production by peripheral blood mononuclear cells (PBMC).
  
  
  METHODS
  PBMC were isolated by Ficoll-Hypaque, and stimulated with anti-CD3 antibodies, phytohaemagglutinin (PHA), lipopolysaccharide (LPS) for 24 hours in the presence or absence of 5 mM NAC. The cytokines produced were measured by enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  Treatment with NAC significantly up-regulates the secretion of IL-1β, IL-5 (interleukin) and IFN-γ (interferon) and down regulates IL-10 production, after anti-CD3 or PHA (p<0.05), but not after LPS stimulation. NAC also significantly increased total IL-12 secretion after anti-CD3 (but not PHA or LPS) stimulation and IL-12p40 after anti-CD3, PHA, and LPS stimulation (p <0.05).
  
  
  CONCLUSIONS
  These results indicate that NAC up-regulated the production of pro-inflammatory cytokines, and down regulated anti-inflammatory cytokine production by PBMC, in a process which may be associated with increased levels of glutathione (GSH). Further work is required to determine whether this increase or decrease in cytokine production is due to direct effect of NAC.
authors.affiliation: Department of Microbiology and Immunology, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Sultanate of Oman;
authors.forename: Ahmed
authors.initials: A
authors.lastname: Al-Shukaili
authors.forename: Suad
authors.initials: S
authors.lastname: Al-Abri
authors.forename: Alia
authors.initials: A
authors.lastname: Al-Ansari
authors.forename: Michele A
authors.initials: MA
authors.lastname: Monteil