Abstract: Objective To investigate the effects of interleukin-27 (IL-27) and its receptor (WSX-1) on the proliferation,
transformation and collagen synthesis of the mouse lung fibroblasts. Methods Cultured mouse lung fibroblasts were treated
with TGF-β1, recombinant murine IL-27, a IL-27 receptor (IL-27R) overexpression vector IL-27R/pCDNA3.1, IL-27 and IL-27R,
or all the 3 combined. MTT assay was used to assess the proliferation of the cells, and RT-PCR and Western blotting were
employed to examine the mRNA and protein expressions of a-smooth muscle actin (α-SMA) and types I and III collagen;
immunofluorescence assay was used to test the expression and location of α-SMA. Results TGF-β1 promoted the cell
proliferation and obviously enhanced α-SMA expression and types I and III collagen synthesis in the fibroblasts. Both IL-27
and IL-27R significantly inhibited the proliferation of the pulmonary fibroblasts and obviously decreased their α-SMA
expression and types I and III collagen synthesis, but when combined,they produced no obvious inhibitory effect on
TGF-1-induced proliferation and transformation of pulmonary fibroblasts. Conclusion Both IL-27 and IL-27R alone can
suppress the proliferation, transformation, and collagen synthesis of mouse pulmonary fibroblasts, but their combined
treatment produces no such inhibitory effect because of the neutralization of exogenous IL-27 by IL-27R to result in the failure
of activating the cell signaling pathways.