- Recently, the aberrant expression of interleukin-1 alpha (IL-1 alpha) mRNA and protein in cultured SSc fibroblasts was reported. Data confirming these findings and preliminary results using antisense oligonucleotides and antisense encoding constructs to reduce IL-1 alpha expression indicate that IL-1 alpha may be a primary factor in determining the abnormal phenotype of the SSc fibroblast. IL-1 alpha is a cytokine with pro-inflammatory and pro-fibrotic properties whose expression is tightly regulated at transcriptional and post-transcriptional levels in normal tissues. The investigators' results indicate that increased levels of IL-1 alpha in SSc fibroblasts are maintained for at least 10 passages in culture (several months), suggesting that the expression of IL-1 alpha mRNA and protein in these cells is likely to be the result of an intrinsic defect in IL-1 alpha regulation. The goals of this project are (i) to determine whether the aberrant expression of IL-1 alpha in SSc fibroblasts results from increased transcription of the IL-1 alpha gene and/or increased mRNA stability; (ii) to define the cis-acting element(s) responsible for the increased IL-1 alpha mRNA expression in SSc fibroblasts; (iii) to identify and characterize the transcription factor(s) that bind to these cis-element(s) and regulate IL-1 alpha transcription; (iv) to determine whether sustained IL-1 alpha expression is SSc fibroblasts is due to autocrine activation by IL-1 alpha. These studies will involve: nuclear run-on assays, Northern hybridization, quantitative RT-PCR, transient and stable transfections, preparation and analysis of reporter constructs (e.g., luciferase), DNA binding protein assays (e.g., DNAse hypersensitivity, footprinting, electrophorectic mobility-shift assay), SSCP, and DNA sequencing. The results of this investigation, it is believed, will yield important new information regarding the molecular basis of the dysregulated IL-1 alpha expression in SSc fibroblasts. This information will further expand our knowledge of the phathogenesis of SSc and provide the basis for the development of rational new therapies for this currently untreatable illness.
| Kawaguchi, Yasushi; McCarthy, Susan A; Watkins, Simon C et al. (2004) Autocrine activation by interleukin 1alpha induces the fibrogenic phenotype of systemic sclerosis fibroblasts. J Rheumatol 31:1946-54 |
| Hu, Bo; Wang, Shuhui; Zhang, Yingze et al. (2003) A nuclear target for interleukin-1alpha: interaction with the growth suppressor necdin modulates proliferation and collagen expression. Proc Natl Acad Sci U S A 100:10008-13 |
| Kawaguchi, Y; Hara, M; Wright, T M (1999) Endogenous IL-1alpha from systemic sclerosis fibroblasts induces IL-6 and PDGF-A. J Clin Invest 103:1253-60 |
