舌下免疫治疗的免疫学机制

Immunological Mechanisms of Sublingual Allergen-specific Immunotherapy

舌下免疫治疗(sublingual immunotherapy,SLIT)通过舌下途径给予变应原诱导变态反应性疾病患者产生变应原特异性免疫耐受,其疗效和安全性已得到广泛认同。然而,目前对SLIT确切机制的认识仍然有限。一般认为SLIT与皮下免疫治疗(subcutaneous immunotherapy,SCIT)相似,可降低患者体内特异性IgE水平并诱导产生保护性IgG4;同时能抑制患者皮肤黏膜局部炎症效应细胞的募集及活性。SLIT的另一个重要作用是将患者体内Th2型为主的免疫反应转变为Th1型反应。目前越来越多的证据显示调节性T淋巴细胞(regulatory T cell,Treg)参与变态反应性疾病的控制,虽然尚缺乏确切证据,但Treg可能在SLIT中起重要作用。更多Treg与变应原外周免疫耐受之间关系的研究,将有助于SLIT机制的进一步阐明。

With the allergen extract administrated through the sublingual route, sublingual immunotherapy （SLIT） is capable of inducing allergen-specific immune tolerance in allergic individuals, and its efficacy and safety profile are well documented. However, the precise mechanisms of SLIT are still unclear. It is generally accepted that, like subcutaneous immunotherapy （SCIT） , SLIT can decrease the serum level of allergen- specific IgE in patients, while inducing the protective IgG4; meanwhile, SLIT inhibits the recruitment and activity of the local effector cells in skin and mucosa. SLIT is also characterized by its reorientation of the predominating Th2-type response to Th1-type. Nowadays, there are accumulating evidences to support the role of regulatory T lymphocytes （Treg） in mediating allergic diseases. Though there is still no confirmative evidence, Treg is probably involved in SLIT. More studies on the relationship between Treg and allergen-specific peripheral tolerance induction should be done to give a further understanding on the mechanisms of SLIT. In this review we discuss the possible immunological mechanisms of SLIT, compare to the SCIT.