Sainz J, Segura-Catena J, Jurado M
Departamento de Epidemiología y Genética Molecular, Deutsches Krebsforschungszentrum, Heidelberg, Alemania.
Methods Find Exp Clin Pharmacol. 2010 Dec;32 Suppl A:9-13.
Fungi of the genus Aspergillus are found everywhere in the natural environment; they cause invasive pulmonary aspergillosis (IPA), an infectious complication common in immunocompromised individuals, which has a mortality rate of up to 90% in patients with hematological malignancy. The first line of defense of innate immunity is the recognition of Aspergillus conidia by dendritic cells or alveolar macrophages. DC-SIGN is an integrin directly involved in this recognition; its degree of expression in immune cells and its functionality may be partly determined by genetic variations. The objective of this study was to determine whether the presence of polymorphisms of a single nucleotide in the DC-SIGN gene increases the risk of invasive pulmonary aspergillosis. For this purpose, the variants DC-SIGN-139A/G (rs2287886) and DC-SIGN+11C/G (rs7252229) were analyzed In 314 subjects (152 patients with hematologic malignancy and 162 healthy controls). Of the 152 hematologic cancer patients, 81 were diagnosed with demonstrated invasive pulmonary aspergillosis per EORTC/IFICG criteria, and the remaining 71 patients had no symptoms of the infection. An association was found between the variant DC-SIGN-139(A/G) and resistance to IPA. Carriers of the allele A (A/A + A/G) were significantly more resistant to the infection than patients with the G/G genotype (p = 0.0574). Analysis of the serum concentration of the galactomannan antigen supported the hypothesis that this polymorphism may be implicated in the susceptibility to suffer invasive pulmonary aspergillosis. Although the difference was not statistically significant, carriers of the allele G had a higher frequency of positive galactomannans than subjects with the genotype A/A (p = 0.1921). These results suggest that the variant DC-SIGN-139(A/G) in the DC-SIGN gene promoter influences the risk of invasive pulmonary aspergillosis and may therefore be used as a genetic biomarker to stratify patients according to risk.
曲霉菌属真菌在自然环境中无处不在;它们会引发侵袭性肺曲霉病(IPA),这是一种在免疫功能低下个体中常见的感染性并发症,在血液系统恶性肿瘤患者中的死亡率高达90%。固有免疫的第一道防线是树突状细胞或肺泡巨噬细胞对曲霉分生孢子的识别。DC-SIGN是一种直接参与这种识别的整合素;其在免疫细胞中的表达程度及其功能可能部分由基因变异决定。本研究的目的是确定DC-SIGN基因中单个核苷酸多态性的存在是否会增加侵袭性肺曲霉病的风险。为此,对314名受试者(152名血液系统恶性肿瘤患者和162名健康对照)分析了DC-SIGN-139A/G(rs2287886)和DC-SIGN+11C/G(rs7252229)变异。在152名血液系统癌症患者中,81名根据欧洲癌症研究与治疗组织/侵袭性真菌感染协作组标准被诊断为确诊的侵袭性肺曲霉病,其余71名患者没有感染症状。发现DC-SIGN-139(A/G)变异与对IPA的抗性之间存在关联。A等位基因携带者(A/A + A/G)比G/G基因型患者对感染的抗性明显更强(p = 0.0574)。半乳甘露聚糖抗原血清浓度分析支持了这一假设,即这种多态性可能与侵袭性肺曲霉病的易感性有关。尽管差异无统计学意义,但G等位基因携带者的半乳甘露聚糖阳性频率高于A/A基因型受试者(p = 0.1921)。这些结果表明,DC-SIGN基因启动子中的DC-SIGN-139(A/G)变异会影响侵袭性肺曲霉病的风险,因此可作为一种基因生物标志物,根据风险对患者进行分层。