Rowley A H, Eckerley C A, Jäck H M, Shulman S T, Baker S C
Department of Pediatrics, The Ronald McDonald Children's Hospital, Maywood, IL 60153, USA.
J Immunol. 1997 Dec 15;159(12):5946-55.
The etiology and pathogenesis of Kawasaki syndrome (KS) remain unknown. Clinical and epidemiologic features of KS are consistent with an infectious cause. To search for an etiologic agent of KS, a phage cDNA expression library was constructed from the aorto-iliac junction of a patient with fatal acute KS and screened with convalescent KS serum followed by anti-human Ig. Unexpectedly, 0.1% of the clones in the library react with anti-human Ig, indicating the presence of many Ig-producing B lymphocytes in the vasculitic tissue. To confirm this finding and to determine the isotypes produced, frozen vascular tissue sections from the patient and paraffin sections from coronary arteries from six additional patients with fatal acute or subacute KS were incubated with Abs to Ig isotypes. Histopathology of the tissues revealed the presence of many plasma cells in the inflammatory infiltrate. IgA was the predominant isotype produced in vascular tissue in all seven KS patients. IgM- and IgG-producing cells were less often detected. We conclude that there is a marked plasma cell response within the vasculitic tissue in KS, with unusual IgA production locally in this nonlymphoid, nonmucosal tissue. We suggest that the prominence of IgA plasma cells in the vascular infiltrate in the early, acute, and subacute stages of KS indicates an Ag-driven immune response to an etiologic agent with a respiratory or gastrointestinal portal of entry and speculate that this unusual immune response is integral to the pathogenesis of the illness.
川崎综合征（KS）的病因和发病机制尚不清楚。KS的临床和流行病学特征与感染性病因相符。为了寻找KS的病原体，从一名死于急性KS的患者的主动脉-髂动脉连接处构建了噬菌体cDNA表达文库，并用恢复期KS血清及抗人Ig进行筛选。出乎意料的是，文库中0.1%的克隆与抗人Ig发生反应，表明血管炎组织中存在许多产生Ig的B淋巴细胞。为了证实这一发现并确定所产生的免疫球蛋白类型，将该患者的冷冻血管组织切片以及另外6例死于急性或亚急性KS患者的冠状动脉石蜡切片与抗免疫球蛋白同型抗体一起孵育。组织的组织病理学显示炎症浸润中有许多浆细胞。在所有7例KS患者中，IgA是血管组织中产生的主要免疫球蛋白类型。产生IgM和IgG的细胞较少被检测到。我们得出结论，KS血管炎组织内存在明显的浆细胞反应，在这种非淋巴、非黏膜组织中局部产生异常的IgA。我们认为，在KS的早期、急性期和亚急性期，血管浸润中IgA浆细胞的突出表明对具有呼吸道或胃肠道进入途径的病原体存在抗原驱动的免疫反应，并推测这种异常免疫反应是该疾病发病机制的组成部分。
