Nally Jarlath E, Whitelegge Julian P, Bassilian Sara, Blanco David R, Lovett Michael A
Division of Infectious Diseases, Department of Medicine, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California, USA.
Infect Immun. 2007 Feb;75(2):766-73. doi: 10.1128/IAI.00741-06. Epub 2006 Nov 13.
Pathogenic Leptospira species adapt to a wide range of environmental conditions during disease transmission and infection. While the proteome of in vitro cultivated Leptospira has been characterized in several studies to date, relatively little is known of the proteome as expressed by Leptospira during disease processes. Isolates of Leptospira obtained from patients suffering the severe pulmonary form of leptospirosis cause acute lethal infection in guinea pigs and chronic asymptomatic infection in rats. Recent studies have demonstrated that protein and lipopolysaccharide constituents of Leptospira recovered from acutely infected guinea pig tissue differ from that of Leptospira in chronically infected rat tissue and in vitro cultivated Leptospira (J. E. Nally, E. Chow, M. C. Fishbein, D. R. Blanco, and M. A. Lovett, Infect. Immun. 73:3251-3260, 2005). In the current study, the proteome of Leptospira expressed during disease processes was characterized relative to that of in vitro cultivated Leptospira (IVCL) after enrichment for hydrophobic membrane proteins with Triton X-114. Protein samples were separated by two-dimensional gel electrophoresis, and antigens expressed during infection were identified by immunoblotting with monospecific antiserum and convalescent rat serum in addition to mass spectrometry. Results suggest a significant increase in the expression of the outer membrane protein Loa22 during acute infection of guinea pigs relative to other outer membrane proteins, whose expression is generally diminished relative to expression in IVCL. Significant amounts of LipL32 are also expressed by Leptospira during acute infection of guinea pigs.
致病性钩端螺旋体在疾病传播和感染过程中能适应广泛的环境条件。尽管迄今为止已有多项研究对体外培养的钩端螺旋体的蛋白质组进行了表征，但对于钩端螺旋体在疾病过程中表达的蛋白质组却知之甚少。从患有严重肺型钩端螺旋体病的患者身上分离出的钩端螺旋体菌株，可在豚鼠中引起急性致死性感染，在大鼠中引起慢性无症状感染。最近的研究表明，从急性感染的豚鼠组织中分离出的钩端螺旋体的蛋白质和脂多糖成分，与慢性感染大鼠组织和体外培养的钩端螺旋体中的成分不同（J. E. Nally、E. Chow、M. C. Fishbein、D. R. Blanco和M. A. Lovett，《感染与免疫》73:3251 - 3260，2005年）。在本研究中，利用Triton X - 114富集疏水膜蛋白后，对疾病过程中表达的钩端螺旋体蛋白质组与体外培养的钩端螺旋体（IVCL）的蛋白质组进行了表征。蛋白质样品通过二维凝胶电泳进行分离，除了质谱分析外，还通过用单特异性抗血清和恢复期大鼠血清进行免疫印迹来鉴定感染期间表达的抗原。结果表明，相对于其他外膜蛋白，豚鼠急性感染期间外膜蛋白Loa22的表达显著增加，而其他外膜蛋白的表达相对于IVCL中的表达通常会减少。钩端螺旋体在豚鼠急性感染期间也会大量表达LipL32。
