Herpers Bjorn L, Yzerman Ed P F, de Jong Ben A W, Bruin Jacob P, Lettinga Kamilla D, Kuipers Saskia, Den Boer Jeroen W, van Hannen Erik J, Rijkers Ger T, van Velzen-Blad Heleen, de Jongh Bartelt M
Department of Medical Microbiology and Immunology, St Antonius Hospital, Nieuwegein, The Netherlands.
Hum Immunol. 2009 Feb;70(2):125-9. doi: 10.1016/j.humimm.2008.11.002. Epub 2008 Dec 13.
Polymorphisms leading to deficiency of mannose-binding lectin (MBL) are associated with predisposition to infection. However, MBL deficiency can be protective against intracellular pathogens that use MBL to enter host cells. The role of MBL genotype and activity in infection with the intracellular pathogen Legionella pneumophila was studied in a large outbreak of legionellosis at a Dutch flower show. A total of 141 patients, 65 exposed asymptomatic exhibition staff members and 670 unexposed blood bank donors were included for the study of MBL2 genotypes and MBL-mediated complement activation. Genotypic MBL deficiency was equally prevalent in patients and controls. Deficient MBL-mediated complement activation was more prevalent in patients. Even in patients with genotypes that confer MBL sufficiency, 20.6% lacked MBL-mediated complement activation. In most patients with MBL-sufficient genotypes who lacked MBL-mediated activation at the acute phase of disease, lectin pathway functionality was restored at convalescence. In conclusion, genotypic MBL deficiency was not a risk factor for legionellosis. However, patients with legionellosis displayed deficient MBL-mediated complement activation even with MBL-sufficient genotypes. Together, these genotypical and functional data suggest that the observed deficiency of lectin pathway activation is an effect of legionellosis rather than a risk factor for acquiring it.
导致甘露糖结合凝集素（MBL）缺乏的多态性与感染易感性相关。然而，MBL缺乏可能对利用MBL进入宿主细胞的细胞内病原体具有保护作用。在荷兰一场花卉展览中发生的军团病大暴发期间，研究了MBL基因型和活性在细胞内病原体嗜肺军团菌感染中的作用。共有141例患者、65名暴露但无症状的展览工作人员和670名未暴露的血库供者被纳入MBL2基因型及MBL介导的补体激活研究。基因型MBL缺乏在患者和对照组中同样常见。MBL介导的补体激活缺乏在患者中更为普遍。即使在具有MBL充足基因型的患者中，20.6%的患者缺乏MBL介导的补体激活。在大多数具有MBL充足基因型且在疾病急性期缺乏MBL介导激活的患者中，凝集素途径功能在恢复期恢复。总之，基因型MBL缺乏不是军团病的危险因素。然而，军团病患者即使具有MBL充足的基因型，也表现出MBL介导的补体激活缺乏。这些基因型和功能数据共同表明，观察到的凝集素途径激活缺乏是军团病的一个结果，而不是获得该病的危险因素。
