Trim21 promotes inflammation in keratinocytes of psoriatic patients.

Abstract

Psoriasis is a skin disease that manifests as itchy, scaly plaques (patches) on the skin. It is associated with both a physical and psychological burden, and affects 0.5-1% of children and 2-3% of the population worldwide. In our research, we mainly focused on psoriatic patients in China and aimed to clarify whether E3 ligase (a type of enzyme), Trim21, plays a pivotal role in regulating inflammation of keratinocytes (a type of cell in the layer of the skin) in psoriasis. For this, we firstly used a technique known in genetics as the knockdown technique, to reduce the expression of Trim21 in keratinocytes. Having 'knocked down' Trim21, we then conducted further tests, such as measuring levels of certain chemicals in the blood that are linked to inflammation, to help us see if targeting Trim21 could be a potential treatment for psoriasis. We found that using the 'knockdown technique' of Trim21 reduced inflammation in keratinocytes. By screening for a series of molecules relating to inflammation, we found that one called p65 interacted directly with Trim21. Finally, we verified that knockdown of Trim21 markedly reduced a certain type of skin lesions (plaques). Thus, our study substantiated that the increased expression of Trim21 in the skin of psoriasis patients could contribute to inflammation. Trim21 could be a potential target in the treatment of psoriasis. Linked Article: Yang et al. Br J Dermatol 2021; 184:111-122.