DEVELOPMENT AND CHARACTERIZATION OF 3D PSORIATIC TISSUE MODEL.

Psoriasis is an inflammatory skin disease marked by hyperproliferation and abnormal keratinocyte differentiation that affects about 2% of the global population.  In this study, we developed a human cell based in vitro psoriatic tissue model from psoriatic fibroblasts and normal keratinocytes using an optimized serum-free culture medium.  When compared to normal skin reconstructs, confocal microscopic evaluation of stained psoriatic tissue reconstructs revealed: 1) hyperproliferation of basal epithelial cells (Ki67), 2) increased STAT 3, and elafin expression, 3) reduced levels of filaggrin, and 4) similar pattern of cytokeratin 10 expression to that of the normal skin reconstruct.  RT-PCR analysis of the psoriatic tissue model also showed overexpression of HBD-2, psoriasin, elafin, and neutrophil chemotactic cytokines such as growth-related oncogene alpha (GROα), interleukin-8 (IL-8), and epithelial cell derived neutrophil-activating peptide 78 (ENA-78).  Similar to the in vivo situation, cytokine analysis of culture supernatants from the psoriatic tissue model showed increased release of IL-6 (9 fold), IL-8 (5.9 fold), and IP-10 (2 fold) when compared to normal reconstructed epidermal tissues.  Topical exposure of the psoriatic tissue to the therapeutic agent calcipotriol hydrate showed a dose dependent decrease in HBD-2 and psoriasin gene expression by 2000 and 380 fold, respectively.  In conclusion, the psoriatic tissue model mimics its in vivo counterpart in terms of tissue morphology, structure, gene expression (human beta defensin 2, psoriasin, and elafin), and cytokine release (IL-6, IL-8, GM-CSF).  Availability of a well- characterized in vitro psoriatic tissue model will be a valuable tool to study the biology of psoriasis, enhance understanding of the disease, and accelerate the development of therapeutic candidates.

Calgranulin A, Calgranulin B, Calgranulin C, Cytokeratin 10, Effector proteins, Elafin, ENA-78, Epithelial cell derived neutrophil-activating peptide 78 (ENA-78), Filaggrin, GCP-2, GM-CSF, GROα, Human beta defensin-2, Human beta defensin-3, Hyperproliferation, IL-6, IL-8, Interleukin-8, IP-10, IP-9, Ki67, LL-37, MIP-3a, Psoriasin, Psoriasis, Psoriasis model, Secretory Leukocyte Peptidase Inhibitor, SOR-300-FT, STAT 3, TLR2, Transglutaminase

Calcipotriol hydrate