Analysis of epigenetic control of IL-23 expression in keratinocytes

Beneficiary: Dr Cord Brakebusch, Professor, Section of Molecular Pathology, BRIC, Department of Biomedical Sciences, University of Copenhagen

Grant: DKK 2,140,000

This study seeks new targets to reduce the formation of psoriatic lesions. A novel epigenetic mechanism, which is known to induce IL-23 in psoriasis, is also found in non-lesioned skin and may hold promise.

Psoriasis is a chronic inflammatory skin disease that involves a complex crosstalk between immune cells and skin cells (keratinocytes). While the etiology of psoriasis is basically unknown, many researchers have gauged the elements of this crosstalk – in many models. During this work, they have shown that there are multiple different, yet intertwining mechanisms underlying the disease.

One is that monoclonal antibodies that target the IL-23/IL-17 immune axis have demonstrated impressive clinical efficacy in patients with moderate-severe psoriasis. There are however, still many missing pieces of the puzzle to fully understand how this disease initiates and develops.

Dr Cord Brakebusch’s team has demonstrated that keratinocyte-derived IL-23 is sufficient to cause chronic skin inflammation in mice. Furthermore, they have elucidated an epigenetic mechanism which controls IL-23 expression and it is explained that the epigenetic control mechanism has been shown not just in active psoriasis lesions, but also, albeit to a lesser extent, in normal-appearing skin of psoriasis patients.

This suggests that the epigenetic alterations might precede the development of psoriasis lesions, and the team now wants to identify and validate targets for small molecule drugs that may prevent excessive IL-23 expression by keratinocytes through this epigenetic mechanism.

As a long-term goal for the study and its potential findings Dr Brakebusch and his team hope that topically administrated small molecular weight inhibitors could prevent excessive IL-23 production by keratinocytes – and ultimately aim at reducing the formation of psoriatic lesions.