Kamradt Thomas
Klinikum der Friedrich Schiller Universität Jena, 07743 Jena, Germany.
Discov Med. 2005 Jun;5(27):283-7.
Extract: In western countries the prevalence and incidence of allergic and autoimmune diseases have been increasing dramatically over the last 50 years. In the last two decades, significant progress has been made towards understanding the genetic basis for susceptibility to autoimmunity or allergy. Genetic factors, however, cannot explain abrupt changes in disease incidence. It is therefore likely that environmental factors, specifically environmental factors that have changed over the last two generations, are critical for the increasing incidence of allergies and autoimmune diseases. Traditionally, autoimmune diseases such as multiple sclerosis (MS), type I diabetes, or rheumatoid arthritis (RA) are believed to have resulted from aberrant immune response to pathogens. In contrast, the "hygiene hypothesis," first postulated some 20 years ago, proposes that a lack of infections, especially during early childhood, predisposes one to the aberrant immune responses against harmless foreign antigens that cause allergic diseases such as rhinitis, atopic dermatitis, and allergic asthma. Several lines of epidemiological, clinical and experimental research point to more complex connections, either protective or pathogenic, between infection, allergy and autoimmunity.
在西方国家，过去50年中过敏性和自身免疫性疾病的患病率和发病率急剧上升。在过去二十年里，在理解自身免疫或过敏易感性的遗传基础方面取得了重大进展。然而，遗传因素无法解释疾病发病率的突然变化。因此，环境因素，特别是过去两代人发生变化的环境因素，可能是导致过敏和自身免疫性疾病发病率上升的关键因素。传统上，自身免疫性疾病，如多发性硬化症（MS）、I型糖尿病或类风湿性关节炎（RA），被认为是由对病原体的异常免疫反应引起的。相比之下，大约20年前首次提出的“卫生假说”认为，缺乏感染，尤其是在幼儿期，会使人易患针对无害外来抗原的异常免疫反应，从而引发过敏性疾病，如鼻炎、特应性皮炎和过敏性哮喘。多项流行病学、临床和实验研究表明，感染、过敏和自身免疫之间存在更复杂的联系，这些联系可能是保护性的，也可能是致病性的。
