Regulation of eotaxin expression in skin allergic diseases

Introduction
As a key chemotactic factor during Eos recruitment on the allergic inflammation site, eotaxin is regarded as one of the important therapeutic targets. Aim: To address the expression and regulation mechanism of eotaxin, which constitutes an important procedure in skin allergic disease and a target for drug therapy.

Material and methods
An allergic contact dermatitis (ACD) model of mouse was established. Immunohistochemical method (ICH) and flow cytometry method (FCM) were used to determine the amounts of CD4+ and CD8+ T cells and their ratios. The eotaxin mRNA and protein were evaluated by real-time PCR, ICH and western-blotting method. Nuclear factor-kB (NF-kB) nuclear translocation and STAT6 phosphorylation were studied by EMSA and western-blotting methods.

Results
We confirmed that both CD4+ and CD8+ T cells in mouse blood and tissue increased during the allergic process, FBs was the main source for eotaxin under the allergic condition. Both TNF-a and IL-4 showed synergic effects on the up-regulation of eotaxin mRNA and protein in KC and FBs. Eotaxin can be expressed via NF-kB and STAT6 transcription after KC and FBs were stimulated by TNF-a and IL-4.

Conclusions
The obvious up-regulation of eotaxin expression in skin tissue of the mouse ACD model was confirmed, the exact expression site and dynamic process was determined both in vivo and in vitro. The eotaxin expression ability of FBs outperformed that of KC, and eotaxin expression can be regulated by TNF-a and IL-4 via NF-kB and STAT6. The overall findings may pave the way for discovering targets for new drugs and new therapeutic drugs for treating allergic diseases.