Psoriasis presents a unique opportunity to dissect the interplay between protective regulatory T cells, and pathogenic Th1 and Th17 type T cells. Findings in psoriasis of Treg dysfunction in combination with high IL-6 levels and the capacity of this cytokine to inhibit regulatory T cell function and stimulate Th17 differentiation may explain observed alterations in psoriatic T cell response. Based upon our observations that a) IL-6 is produced at high levels in critical T cell microenvironments in psoriatic skin, b) that IL-6 can inhibit suppression of effector cell proliferation by human T regulatory cells, and c) that psoriatic T cells exhibit hyper-responsive phosphorylation of STAT3, it is critical to test whether IL-6 and and/or other STAT3-activating cytokines favor escape for Tmem/eff cells from suppression. Thus we will I.) Determine whether the psoriatic lesional milieu can create functionally decreased psoriatic Treg activity via effector T cells becoming refractive to suppression by psoriatic regulatory T cells. On the Treg side, our published and preliminary data demonstrate that psoriatic Tregs are functionally less effective, are insufficient numerically to functionally suppress in developed psoriatic lesions, have decreased numbers of CCR5+ Tregs, decreased chemotaxis to Rantes and Mip1a, decreased CD73, and increased IFI27 (ISG12). Furthermore, over-expressed psoriatic STAT3-associated signaling cytokines such as IL-6, IL-23, and IL-22, in combination with IL- 1 and TGFb, can divert the differentiation of Tregs from precursors away from a regulatory phenotype and toward a pathogenic Th17 cell pathway, or even cause trans-differentiative re-programming of committed Tregs into IFNg-, IL-17-,or TNF-producing Teff cells. Therefore, we will also II.) Determine whether the psoriatic lesional milieu can a) induce the abnormal profile of psoriatic Treg cells, b) divert differentiation away from Treg development toward Th17's, or c) cause trans-differentiative re-programming of Tregs into Teff cells. Designing a model that recapitulates the effector/regulatory T cells changes observed in psoriasis will allow for high throughput analysis of potential therapeutic reagents and opens new research opportunities in diseases where regulatory T cells play a role.

Public Health Relevance

The current application proposes to dissect the interplay between protective regulatory T cells, and pathogenic Th1 and Th17 type T cells. A more comprehensive understanding of the relationship between regulatory and pathogenic effector T cells in psoriasis is necessary to gain insight into the mechanism(s) of action for drugs already in use for psoriasis, Crohn's and rheumatoid/psoriatic arthritis. Better understanding of the mechanisms for efficacious therapies will help to improve the next generation of therapeutics and identify more tailored targets for intervention.

National Institute of Health (NIH)
Research Project (R01)
Project #
Application #
Study Section
Arthritis, Connective Tissue and Skin Study Section (ACTS)
Program Officer
Cibotti, Ricardo
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Case Western Reserve University
Schools of Medicine
United States
Zip Code
Soler, David C; Sugiyama, Hideaki; Young, Andrew B et al. (2013) Psoriasis patients exhibit impairment of the high potency CCR5(+) T regulatory cell subset. Clin Immunol 149:111-8
Golden, Jackelyn B; McCormick, Thomas S; Ward, Nicole L (2013) IL-17 in psoriasis: implications for therapy and cardiovascular co-morbidities. Cytokine 62:195-201
Goodman, Wendy A; Cooper, Kevin D; McCormick, Thomas S (2012) Regulation generation: the suppressive functions of human regulatory T cells. Crit Rev Immunol 32:65-79
Goodman, Wendy A; Young, Andrew B; McCormick, Thomas S et al. (2011) Stat3 phosphorylation mediates resistance of primary human T cells to regulatory T cell suppression. J Immunol 186:3336-45
Chan, Derek V; Somani, Ally-Khan; Young, Andrew B et al. (2011) Signal peptide cleavage is essential for surface expression of a regulatory T cell surface protein, leucine rich repeat containing 32 (LRRC32). BMC Biochem 12:27
Goodman, Wendy A; Levine, Alan D; Massari, Jessica V et al. (2009) IL-6 signaling in psoriasis prevents immune suppression by regulatory T cells. J Immunol 183:3170-6
Love, William E; Miedler, John D; Smith, Molly K et al. (2008) The spectrum of primary cutaneous nodular amyloidosis: Two illustrative cases. J Am Acad Dermatol 58:S33-5
Ismail, Sahar A; Han, Rujing; Sanborn, Sharon L et al. (2007) Immunohistochemical staining for CD45R isoforms in paraffin sections to diagnose mycosis fungoides-type cutaneous T-cell lymphoma. J Am Acad Dermatol 56:635-42
Miller, Janine D; Baron, Elma D; Scull, Heather et al. (2007) Photodynamic therapy with the phthalocyanine photosensitizer Pc 4: the case experience with preclinical mechanistic and early clinical-translational studies. Toxicol Appl Pharmacol 224:290-9