Systemic sclerosis (SSc) affects approximately 200,000 individuals in the USA alone. Treatment for SSc is difficult, incomplete, and not curative. Th2-cytokine polarized T cell responses are postulated to mediate inflammation, auto-antibody production and development of fibrosis in SSc, yet there remains a wide knowledge gap on specific molecules involved in the Th2 cytokine-driven immunopathology of SSc. Interleukin- 31 (IL-31) is a newly identified cytokine produced by activated Th2 T cells and overproduction of IL-31 in mouse skin has been shown to cause severe pruritus, alopecia and skin lesions similar to those seen in SSc. IL-31 signals exclusively through a heterodimeric receptor complex consisting of IL-31 receptor alpha (IL-31RA) and oncostatin M receptor beta (OSMR?). Preliminary data from our laboratory show elevated expression of IL-31, IL-31RA and OSMR? in skin lesions of bleomycin-induced SSc. In addition, key Th-2 cytokines IL-4 and IL-13 directly increased IL-31RA expression in inflamed macrophages. These findings support our central hypothesis that Th2 cytokines and IL-31-IL-31RA interactions play an essential role in the immunopathology of SSc. The objective of this application is to identify the in vivo regulation of the IL-31RA subunit expression by IL-4 and IL-13 and the role of IL-31 in the immunopathology of SSc. Our long-term goal is to understand how the Th2 cytokines and IL-31-IL-31RA interactions can be manipulated for preventive and therapeutic purposes in SSc. This hypothesis will be tested by pursuing two specific aims: 1) Determine the molecular regulation of IL-31RA expression by IL-4 and IL-13 using a mouse model of bleomycin-induced SSc;and 2) Identify the role of IL-31-IL-31RA interactions in the immunopathology of SSc. Under the first aim, we will test the hypothesis that the Th2 cytokines, IL-4 and IL-13 regulate IL-31RA expression in skin cells in a mouse model of bleomycin-induced SSc.
This aim will establish the cells and Th2 cytokine signaling pathways involved in IL-31 and IL-31RA expression.
The second aim will compare wild type and IL-31RA deficient mice for the evolution of disease phenotypes including inflammation, auto-antibody production and fibrosis in the skin during bleomycin-induced SSc.
This aim will provide proof of concept for the potential therapeutic benefit of inhibiting IL-31-IL-31RA interactions in SSc. The approach is innovative by testing molecular interactions among IL-4, IL-13 and IL-31 and their pathologic skin responses using a mouse model of bleomycin-induced SSc and knock-out mice. The proposed research is significant, because completion of this study will increase our knowledge of the mechanisms causing SSc and will lead to better medical treatments, cure or prevention.

Public Health Relevance

Systemic sclerosis (SSc) is an incurable, disabling, and often fatal disease characterized by fibrosis and vascular ischemia affecting skin and internal organs. Validation of the functional association between Th2 cytokines, IL-31-IL-31RA interactions and disease phenotypes of SSc may provide new avenues for clinical interventions of SSc.

National Institute of Health (NIH)
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Small Research Grants (R03)
Project #
Application #
Study Section
Special Emphasis Panel (ZAR1-EHB (M1))
Program Officer
Mancini, Marie
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Cincinnati Children's Hospital Medical Center
United States
Zip Code
Singh, Brijendra; Kasam, Rajesh K; Sontake, Vishwaraj et al. (2017) Repetitive intradermal bleomycin injections evoke T-helper cell 2 cytokine-driven pulmonary fibrosis. Am J Physiol Lung Cell Mol Physiol 313:L796-L806
Glasser, Stephan W; Hagood, James S; Wong, Simon et al. (2016) Mechanisms of Lung Fibrosis Resolution. Am J Pathol 186:1066-77
Madala, Satish K; Thomas, George; Edukulla, Ramakrishna et al. (2016) p70 ribosomal S6 kinase regulates subpleural fibrosis following transforming growth factor-? expression in the lung. Am J Physiol Lung Cell Mol Physiol 310:L175-86
Singh, Brijendra; Jegga, Anil G; Shanmukhappa, Kumar S et al. (2016) IL-31-Driven Skin Remodeling Involves Epidermal Cell Proliferation and Thickening That Lead to Impaired Skin-Barrier Function. PLoS One 11:e0161877
Madala, Satish K; Sontake, Vishwaraj; Edukulla, Ramakrishna et al. (2016) Unique and Redundant Functions of p70 Ribosomal S6 Kinase Isoforms Regulate Mesenchymal Cell Proliferation and Migration in Pulmonary Fibrosis. Am J Respir Cell Mol Biol 55:792-803
Sontake, Vishwaraj; Shanmukhappa, Shiva K; DiPasquale, Betsy A et al. (2015) Fibrocytes Regulate Wilms Tumor 1-Positive Cell Accumulation in Severe Fibrotic Lung Disease. J Immunol 195:3978-91
Madala, Satish K (2015) Reply: tissue fibrocytes are a subpopulation of macrophages. Am J Respir Cell Mol Biol 52:138
Edukulla, Ramakrishna; Singh, Brijendra; Jegga, Anil G et al. (2015) Th2 Cytokines Augment IL-31/IL-31RA Interactions via STAT6-dependent IL-31RA Expression. J Biol Chem 290:13510-20
Madala, Satish K; Korfhagen, Thomas R; Schmidt, Stephanie et al. (2014) Inhibition of the ?v?6 integrin leads to limited alteration of TGF-?-induced pulmonary fibrosis. Am J Physiol Lung Cell Mol Physiol 306:L726-35
Madala, Satish K; Edukulla, Ramakrishna; Schmidt, Stephanie et al. (2014) Bone marrow-derived stromal cells are invasive and hyperproliferative and alter transforming growth factor-?-induced pulmonary fibrosis. Am J Respir Cell Mol Biol 50:777-86

Showing the most recent 10 out of 11 publications