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

 Previous Article  |  Next Article 

Infection and Immunity, October 2003, p. 5994-6003, Vol. 71, No. 10
0019-9567/03/$08.00+0     DOI: 10.1128/IAI.71.10.5994-6003.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.

Inhibition of Phagocytosis by Haemophilus ducreyi Requires Expression of the LspA1 and LspA2 Proteins

Merja Vakevainen,1 Steven Greenberg,2 and Eric J. Hansen1*

Department of Microbiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9048 ,1 Departments of Medicine and Pharmacology, Columbia University, New York, New York 100322

Received 29 March 2003/ Returned for modification 3 July 2003/ Accepted 23 July 2003

Haemophilus ducreyi previously has been shown to inhibit the phagocytosis of both secondary targets and itself by certain cells in vitro. Wild-type H. ducreyi strain 35000HP contains two genes, lspA1 and lspA2, whose encoded protein products are predicted to be 456 and 543 kDa, respectively. An isogenic mutant of H. ducreyi 35000HP with inactivated lspA1 and lspA2 genes has been shown to exhibit substantially decreased virulence in the temperature-dependent rabbit model for chancroid. This lspA1 lspA2 mutant was tested for its ability to inhibit phagocytosis of immunoglobulin G-opsonized particles by differentiated HL-60 and U-937 cells and by J774A.1 cells. The wild-type strain H. ducreyi 35000HP readily inhibited phagocytosis, whereas the lspA1 lspA2 mutant was unable to inhibit phagocytosis. Similarly, the wild-type strain was resistant to phagocytosis, whereas the lspA1 lspA2 mutant was readily engulfed by phagocytes. This inhibitory effect of wild-type H. ducreyi on phagocytic activity was primarily associated with live bacterial cells but could also be found, under certain conditions, in concentrated H. ducreyi culture supernatant fluids that lacked detectable outer membrane fragments. Both the wild-type strain and the lspA1 lspA2 mutant attached to phagocytes at similar levels. These results indicate that the LspA1 and LspA2 proteins of H. ducreyi are involved, directly or indirectly, in the antiphagocytic activity of this pathogen, and they provide a possible explanation for the greatly reduced virulence of the lspA1 lspA2 mutant.

* Corresponding author. Mailing address: Department of Microbiology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-9048. Phone: (214) 648-5974. Fax: (214) 648-5905. E-mail: eric.hansen{at}utsouthwestern.edu.

Editor: J. N. Weiser

Infection and Immunity, October 2003, p. 5994-6003, Vol. 71, No. 10
0019-9567/03/$08.00+0     DOI: 10.1128/IAI.71.10.5994-6003.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Labandeira-Rey, M., Mock, J. R., Hansen, E. J. (2009). Regulation of Expression of the Haemophilus ducreyi LspB and LspA2 Proteins by CpxR. Infect. Immun. 77: 3402-3411 [Abstract] [Full Text]  
  • Deng, K., Mock, J. R., Greenberg, S., van Oers, N. S. C., Hansen, E. J. (2008). Haemophilus ducreyi LspA Proteins Are Tyrosine Phosphorylated by Macrophage-Encoded Protein Tyrosine Kinases. Infect. Immun. 76: 4692-4702 [Abstract] [Full Text]  
  • Bauer, M. E., Fortney, K. R., Harrison, A., Janowicz, D. M., Munson, R. S., Spinola, S. M. (2008). Identification of Haemophilus ducreyi genes expressed during human infection. Microbiology 154: 1152-1160 [Abstract] [Full Text]  
  • Humphreys, T. L., Li, L., Li, X., Janowicz, D. M., Fortney, K. R., Zhao, Q., Li, W., McClintick, J., Katz, B. P., Wilkes, D. S., Edenberg, H. J., Spinola, S. M. (2007). Dysregulated Immune Profiles for Skin and Dendritic Cells Are Associated with Increased Host Susceptibility to Haemophilus ducreyi Infection in Human Volunteers. Infect. Immun. 75: 5686-5697 [Abstract] [Full Text]  
  • Banks, K. E., Humphreys, T. L., Li, W., Katz, B. P., Wilkes, D. S., Spinola, S. M. (2007). Haemophilus ducreyi Partially Activates Human Myeloid Dendritic Cells. Infect. Immun. 75: 5678-5685 [Abstract] [Full Text]  
  • Mock, J. R., Vakevainen, M., Deng, K., Latimer, J. L., Young, J. A., van Oers, N. S. C., Greenberg, S., Hansen, E. J. (2005). Haemophilus ducreyi Targets Src Family Protein Tyrosine Kinases To Inhibit Phagocytic Signaling. Infect. Immun. 73: 7808-7816 [Abstract] [Full Text]  
  • Julio, S. M., Cotter, P. A. (2005). Characterization of the Filamentous Hemagglutinin-Like Protein FhaS in Bordetella bronchiseptica. Infect. Immun. 73: 4960-4971 [Abstract] [Full Text]  
  • Janowicz, D. M., Fortney, K. R., Katz, B. P., Latimer, J. L., Deng, K., Hansen, E. J., Spinola, S. M. (2004). Expression of the LspA1 and LspA2 Proteins by Haemophilus ducreyi Is Required for Virulence in Human Volunteers. Infect. Immun. 72: 4528-4533 [Abstract] [Full Text]  
  • Ward, C. K., Mock, J. R., Hansen, E. J. (2004). The LspB Protein Is Involved in the Secretion of the LspA1 and LspA2 Proteins by Haemophilus ducreyi. Infect. Immun. 72: 1874-1884 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»