This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Merien, F. Articles by Perolat, P. Search for Related Content PubMed PubMed Citation Articles by Merien, F. Articles by Perolat, P.

 Previous Article  |  Next Article 

Infect. Immun., Feb 1997, 729-738, Vol 65, No. 2
Copyright © 1997, American Society for Microbiology

Invasion of Vero cells and induction of apoptosis in macrophages by pathogenic Leptospira interrogans are correlated with virulence

F Merien, G Baranton and P Perolat
Laboratoire des Leptospires, Institut Pasteur, Noumea, New Caledonia, France.

Interactions of virulent Leptospira interrogans serovar icterohaemorrhagiae strain Verdun with Vero cells (African green monkey kidney fibroblasts) and a monocyte-macrophage-like cell line (J774A.1) were assayed by a double-fluorescence immunolabelling method. Infectivity profiles were investigated according to (i) the duration of contact between leptospires and eukaryotic cells and (ii) the number of in vitro passages after primary isolation from lethally infected guinea pigs. Comparative experiments were conducted with the corresponding high-passage avirulent variant and the saprophytic leptospire Leptospira biflexa Patoc I. In Vero cells, virulent leptospires were quickly internalized from 20 min postinfection, whereas avirulent and saprophytic strains remained extracellularly located. In addition, the virulent strain demonstrated an ability to actively invade the monocyte- macrophage-like J774A.1 cells during the early stages of contact and to induce programmed cell death, as shown by the detection of oligonucleosomes in a quantitative sandwich enzyme immunoassay. In both cellular systems, subsequent in vitro subcultures demonstrated a progressive decrease of the invasiveness, pointing out the necessity of using primocultures of Leptospira for virulence studies. Invasiveness of virulent leptospires was significantly inhibited with monodansylcadaverine, indicating that internalization was dependent on receptor-mediated endocytosis. Invasion of epithelial cells and induction of apoptosis in macrophages may be related to the pathogenicity of Leptospira, and both could contribute to its ability to survive in the host and to escape from the immune response.

This article has been cited by other articles:

• Matsunaga, J., Werneid, K., Zuerner, R. L., Frank, A., Haake, D. A. (2006). LipL46 is a novel surface-exposed lipoprotein expressed during leptospiral dissemination in the mammalian host. Microbiology 152: 3777-3786 [Abstract] [Full Text]  
• Vernel-Pauillac, F., Merien, F. (2006). Proinflammatory and Immunomodulatory Cytokine mRNA Time Course Profiles in Hamsters Infected with a Virulent Variant of Leptospira interrogans. Infect. Immun. 74: 4172-4179 [Abstract] [Full Text]  
• Desnues, B., Ihrig, M., Raoult, D., Mege, J.-L. (2006). Whipple's Disease: a Macrophage Disease. CVI 13: 170-178 [Full Text]  
• Branger, C., Chatrenet, B., Gauvrit, A., Aviat, F., Aubert, A., Bach, J. M., Andre-Fontaine, G. (2005). Protection against Leptospira interrogans Sensu Lato Challenge by DNA Immunization with the Gene Encoding Hemolysin-Associated Protein 1. Infect. Immun. 73: 4062-4069 [Abstract] [Full Text]  
• Barocchi, M. A., Ko, A. I., Reis, M. G., McDonald, K. L., Riley, L. W. (2002). Rapid Translocation of Polarized MDCK Cell Monolayers by Leptospira interrogans, an Invasive but Nonintracellular Pathogen. Infect. Immun. 70: 6926-6932 [Abstract] [Full Text]  
• Truccolo, J., Charavay, F., Merien, F., Perolat, P. (2002). Quantitative PCR Assay To Evaluate Ampicillin, Ofloxacin, and Doxycycline for Treatment of Experimental Leptospirosis. Antimicrob. Agents Chemother. 46: 848-853 [Abstract] [Full Text]  
• Levett, P. N. (2001). Leptospirosis. Clin. Microbiol. Rev. 14: 296-326 [Abstract] [Full Text]  
• Guignot, J., Bernet-Camard, M.-F., Pous, C., Plancon, L., Le Bouguenec, C., Servin, A. L. (2001). Polarized Entry of Uropathogenic Afa/Dr Diffusely Adhering Escherichia coli Strain IH11128 into Human Epithelial Cells: Evidence for {alpha}5{beta}1 Integrin Recognition and Subsequent Internalization through a Pathway Involving Caveolae and Dynamic Unstable Microtubules. Infect. Immun. 69: 1856-1868 [Abstract] [Full Text]  
• Barnett, J. K., Barnett, D., Bolin, C. A., Summers, T. A., Wagar, E. A., Cheville, N. F., Hartskeerl, R. A., Haake, D. A. (1999). Expression and Distribution of Leptospiral Outer Membrane Components during Renal Infection of Hamsters. Infect. Immun. 67: 853-861 [Abstract] [Full Text]  
• Clifton, D. R., Goss, R. A., Sahni, S. K., van Antwerp, D., Baggs, R. B., Marder, V. J., Silverman, D. J., Sporn, L. A. (1998). NF-kappa B-dependent inhibition of apoptosis is essential for host cell survival during Rickettsia rickettsii infection. Proc. Natl. Acad. Sci. USA 95: 4646-4651 [Abstract] [Full Text]