Kv1.3 in psoriatic disease: PAP-1, a small molecule inhibitor of Kv1.3 is effective in the SCID mouse psoriasis - Xenograft model
- Author(s): Kundu-Raychaudhuri, S
- Chen, YJ
- Wulff, H
- Raychaudhuri, SP
- et al.
Published Web Locationhttps://doi.org/10.1016/j.jaut.2014.07.003
© 2014. Kv1.3 channels regulate the activation/proliferation of effector memory T cells and thus play a critical role in the pathogenesis of autoimmune diseases. Using a combination of immunohistochemistry, confocal microscopy, flow cytometry and electrophysiology methods we observed a significant enrichment of activated Kv1.3+memory T cells in psoriasis plaques and synovial fluid from patients with psoriasis/psoriatic arthritis (PsA) compared to non-lesional psoriatic skin, normal skin or peripheral blood lympho-mononuclear cells. In invitro studies performed with lesional mononuclear cells or T cells derived from skin and joints of psoriatic disease, the small molecule Kv1.3 blocker PAP-1 dose-dependently inhibited proliferation and suppressed IL-2 and IFN-γ production. To further substantiate the pathologic role of Kv1.3high TEMcells in psoriatic disease we tested whether PAP-1 is able to improve psoriatic disease pathology in the SCID mouse-psoriasis skin xenograft model. Following four weeks of daily treatment with 2% PAP-1 ointment we noticed about 50% reduction in the epidermal thickness (rete peg length) and the number of CD3+lymphocytes/mm2of dermis decreased by 85%. Vehicle treated and untreated plaques in contrast remained unchanged and showed no reduction in epidermis thickness and infiltrating CD3+T cells and HLA-DR+T cells. Based on these results we propose the development of Kv1.3 targeted topical immunotherapy for psoriasis and possibly for other inflammatory skin conditions, where effector memory T cells are involved in the pathogenesis.