The expression of cytokines and cytokine receptors was investigated in enriched populations of human fetal Schwann cells by reverse transcribed-PCR and enzyme-linked immunosorbent assay. Human fetal Schwann cells constitutively expressed mRNA of IL-1beta, IL-6, IL-8, IL-11, IL-12, IL-15 and TGF-beta, and also cytokine receptors for IL-1, IL-4, IL-6, IL-8, IL-13, tissue necrosis factor and gp130. The expression of IL-1beta, IL-6 and IL-15 was upregulated following treatment with IL-1beta or TGF-beta. The protein levels of IL-6 were increased with IL-1beta treatment, but were decreased with IFN-gamma treatment. Human Schwann cells may respond to cytokine signals in the nerve injury sites and modify the pathological conditions by secreting cytokines. The secreted cytokines may play a role in leukocyte recruitment and exacerbation of axonal injury process.