LsaA, an antigen involved in cell attachment and invasion, is expressed by Lawsonia intracellularis during infection in vitro and in vivo

McCluskey, J., Hannigan, J., Harris, J. D., Wren, B. and Smith, D. G.E. (2002) LsaA, an antigen involved in cell attachment and invasion, is expressed by Lawsonia intracellularis during infection in vitro and in vivo. Infection and Immunity, 70(6), pp. 2899-2907. (doi: 10.1128/IAI.70.6.2899-2907.2002)

Abstract

<i>Lawsonia intracellularis</i> has been identified recently as the etiological agent of proliferative enteropathies, which are characterized by intestinal epithelial hyperplasia and associated moderate immune responses. This disease complex has been reported in a broad range of animals, prevalently in pigs, and <i>L. Intracellularis</i> has been linked with ulcerative colitis in humans. <i>L. Intracellularis</i> an obligate intracellular bacterium, and the pathogenic mechanisms used to cause disease are unknown. Using in vitro-grown organisms as a source of genomic DNA, we identified a <i>Lawsonia</i> gene which encodes a surface antigen, LsaA (for <i>Lawsonia</i> surface antigen), associated with attachment to and entry into cells. The deduced amino acid sequence of this protein showed some similarity to members of a novel protein family identified in a number of other bacterial pathogens but for which roles are not fully defined. Transcription of this gene was detected by reverse transcription-PCR in <i>L. Intracellularis</i> grown in vitro in IEC18 cells and in bacteria present in ileal tissue from infected animals. Immunohistochemistry with specific monoclonal antibody and immunoblotting with sera from infected animals demonstrated that LsaA protein is synthesized by <i>L. Intracellularis</i> during infection. Expression of this gene during infection in vitro and in vivo suggests that this surface antigen is involved during infection, and phenotypic analysis indicated a role during <i>L. Intracellularis</i> attachment to and entry into intestinal epithelial cells.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Smith, Professor David
• Authors: McCluskey, J., Hannigan, J., Harris, J. D., Wren, B., and Smith, D. G.E.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: Infection and Immunity
• Journal Abbr.: IAI
• Publisher: American Society for Microbiology
• ISSN: 0019-9567
• ISSN (Online): 1098-5522