Strannegård O, Cello J, Bjarnason R, Sigurbergsson F, Sigurs N
Department of Clinical Virology, Medical Faculty, University of Göteborg, Sweden.
Pediatr Allergy Immunol. 1997 Feb;8(1):1-6. doi: 10.1111/j.1399-3038.1997.tb00134.x.
Forty-five children who had been hospitalized with bronchiolitis caused by respiratory syncytial virus (RSV) at a mean age of 4 months, and 90 matched control children, were tested for occurrence of RSV antibodies at one year of age. Of the children who had suffered from bronchiolitis, forty had demonstrable IgG antibodies, whereas the remaining five only had IgA antibodies against RSV. In the control group, 42% were RSV seropositive. The anti-RSV IgA antibody titres tended to be higher in patients with bronchiolitis than in controls and a larger proportion of the seropositive children in the former than in the latter group had demonstrable IgG antibodies. These findings suggest that RSV infections causing bronchiolitis are more often associated with a strong antibody response than are mild cases of the infection. Follow-up of the children at 3 years of age showed that allergic sensitization and development of asthma had occurred much more frequently in children with past RSV bronchiolitis than in controls. Children with past RSV bronchiolitis who later developed allergic sensitization had elevated RSV IgA antibody titres at one year of age more frequently than children with past RSV-bronchiolitis, who were not sensitized (p = 0.015). No significant differences regarding IgG antibody titres were observed. Since IgA, similarly as IgE, antibody formation is strongly Th2 cell dependent, the results are compatible with other findings suggesting that RSV has an unusual propensity to activate the Th2 cell system. This may contribute to the pathological picture of bronchiolitis in small children and at the same time render the infected child predisposed for later development of allergic sensitization. RSV bronchiolitis may thus be an important risk factor for later development of atopic disease although it cannot be excluded that the bronchiolitis simply serves as a marker that predict later development of atopy.
45名曾因呼吸道合胞病毒（RSV）引起的细支气管炎而住院的儿童，平均年龄为4个月，以及90名匹配的对照儿童，在1岁时接受了RSV抗体检测。在患细支气管炎的儿童中，40名有可检测到的IgG抗体，而其余5名仅有抗RSV的IgA抗体。在对照组中，42%为RSV血清阳性。细支气管炎患者的抗RSV IgA抗体滴度往往高于对照组，且前者血清阳性儿童中可检测到IgG抗体的比例高于后者。这些发现表明，与轻度感染病例相比，导致细支气管炎的RSV感染更常与强烈的抗体反应相关。对这些儿童3岁时的随访表明，既往有RSV细支气管炎的儿童发生过敏致敏和哮喘的频率比对照组高得多。与未致敏的既往有RSV细支气管炎的儿童相比，后来发生过敏致敏的既往有RSV细支气管炎的儿童在1岁时RSV IgA抗体滴度升高的频率更高（p = 0.015）。未观察到IgG抗体滴度有显著差异。由于IgA与IgE一样，抗体形成强烈依赖于Th2细胞，这些结果与其他研究结果一致，表明RSV具有激活Th2细胞系统的异常倾向。这可能导致幼儿细支气管炎的病理表现，同时使受感染儿童易患后期过敏致敏。因此，RSV细支气管炎可能是后期发生特应性疾病的一个重要危险因素，尽管不能排除细支气管炎仅仅作为预测后期特应性疾病发生的一个标志物。
