Background: Monocyte chemotactic and activating factor (MCAF) is a novel inflammatory cytokine belonging to the chemokine superfamily and stimulates chemotaxis and activation of monocytes. Increased production of inflammatory cytokines has been shown in patients with end-stage renal disease (ESRD). This study was thus conducted to determine plasma MCAF in patients with ESRD.
Methods: Plasma levels of MCAF were determined by ELISA. Gene expression of MCAF in PBMC was assessed by RT-PCR followed by southern blot hybridization.
Results: Plasma MCAF in 72 patients with long-term haemodialysis (HD) (162.4 +/- 58.2 pg/ml) and eight uraemic patients not yet dialysed (167.6 +/- 57.7 pg/ml) was found to exceed significantly the level in 24 normal subjects (86.0 +/- 19.4 pg/ml). MCAF before HD session in long-term HD patients was the same whether HD was carried out with either cellulosic (CUP) or synthetic (PMMA) membrane dialysers. Intradialytic increase in plasma MCAF during a single HD session was observed in both patient groups dialysed with CUP or PMMA membranes. The results of RT-PCR analysis indicated that haemodialysis stimulates the gene expression of MCAF in PBMC in vivo.
Conclusions: The present results indicate that increased levels of plasma MCAF may promote the activation of monocytes in patients with ESRD.