The present invention relates to a composition for preventing or treating autoimmune diseases, containing high temperature requirement protein A2 (HtrA2) as an active ingredient. The HtrA2 according to the present invention reduces the expression of STAT3, which is a Th17 cell transcription factor, inhibits the expression of inflammatory cytokines, and promotes the activity of a regulatory T cell (Treg), thereby regulating an excessive immune response through a mechanism, and thus it is possible to effectively treat autoimmune diseases caused by the abnormal regulation of an inflammatory response and various immune responses.La présente invention concerne une composition pour la prévention ou le traitement de maladies auto-immunes, contenant la protéine A2 à exigence de température élevée (HtrA2) comme principe actif. LHtrA2, selon la présente invention, réduit lexpression de STAT3, qui est un facteur de transcription des lymphocytes Th17, inhibe lexpression de cytokines inflammatoires et favorise lactivité dun lymphocyte T régulateur (Treg), régulant ainsi une réponse immunitaire excessive par lintermédiaire dun mécanisme et, par conséquent, il est possible de traiter efficacement des maladies auto-immunes provoquées par la régulation anormale dune réponse inflammatoire et de diverses réponses immunitaires.본 발명은 HtrA2(High temperature requirement protein A2) 단백질을 유효성분으로 포함하는 자가면역질환의 예방 또는 치료용 조성물에 관한 것이다. 본 발명에 따른 HtrA2 단백질은 HtrA2 단백질이 Th17 세포의 전사인자인 STAT3의 발현을 감소시키고 염증성 사이토카인의 발현을 억제시키며, 조절 T 세포(Regulatory T cell: Treg)의 활성을 촉진시켜 과도한 면역반응을 조절하는 기작을 통해 이루어지므로, 염증반응 및 각종 면역반응의 조절 이상으로 유발되는 자가면역질환을 효과적으로 치료할 수 있는 효과가 있다.
