CCL18 Expression and Production by Human Alveolar Macrophages in Co-Culture with Lung Fibroblasts

CCL18 is a C-C chemokine produced by human DC and alternatively activated macrophages, and it has been shown that CCL18 augments collagen production by human fibroblasts in vitro (Atamas S.P. et al., 2003). We investigated the interaction of human lung fibroblasts (FBR) and alveolar macrophages (AM) concerning CCL18 production. In a co-culture system consisting of AM layered over human lung FBR in the presence of IL-4, IL-10 or their combination, CCL18 production by AM was significantly higher in FBR-AM co-culture than in AM alone. Additionally, FBR strongly enhanced the up-regulatory effect of IL-4 and IL-10 on…