Fibroblasts grown from SSc lesional skin biopsies constitutively overexpress IC IL-1α; and after stimulation in vitro with TNFα or IL-1β, both icIL-1α and icIL-1 receptor protein antagonist (icIL-1ra) are markedly upregulated compared to normal donor fibroblasts (361). This evidence concerns the gene IL1B and systemic sclerosis.