This Article Full Text Full Text (PDF) Other Versions of this Article: IAI.00905-07v1 75/12/5720    most recent 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 Sarkar, M. Articles by Carlyon, J. A. Search for Related Content PubMed PubMed Citation Articles by Sarkar, M. Articles by Carlyon, J. A.

 Previous Article  |  Next Article 

Infection and Immunity, December 2007, p. 5720-5725, Vol. 75, No. 12
0019-9567/07/$08.00+0     doi:10.1128/IAI.00905-07
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Sialyl-Lewis x-Independent Infection of Human Myeloid Cells by Anaplasma phagocytophilum Strains HZ and HGE1

Madhubanti Sarkar, Dexter V. Reneer, and Jason A. Carlyon^*

Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, Kentucky

Received 3 July 2007/ Returned for modification 7 August 2007/ Accepted 12 September 2007

Anaplasma phagocytophilum, the causative agent of human granulocytic anaplasmosis, is an obligate intracellular bacterium that infects neutrophils and neutrophil precursors. Bacterial recognition of P-selectin glycoprotein ligand-1 (PSGL-1) and the 2,3-sialylated- and 1,3-fucosylated-moiety sialyl-Lewis x (sLe^x), which modifies the PSGL-1 N terminus, is important for adhesion to and invasion of myeloid cells. We have previously demonstrated that A. phagocytophilum organisms of the NCH-1 strain that utilize an sLe^x-modified PSGL-1-independent means of entry can be enriched for by cultivation in undersialylated HL-60 cells that are unable to construct sLe^x. Because it was unknown whether other A. phagocytophilum isolates share this ability, we extended our studies to the geographically diverse strains HZ and HGE1. HL-60 A2 is a clonal cell line that is defective for sialylation and 1,3-fucosyltransferase. HL-60 A2 cell surfaces, therefore, not only lack sLe^x but also are virtually devoid of any other sialic acid- and/or 1,3-fucose-modified glycan. By cultivating HZ and HGE1 in HL-60 A2 cells, we enriched for bacterial subpopulations (termed HZA2 and HGE1A2) that bind and/or infect myeloid cells in the absence of sialic acid and 1,3-fucose and in the presence of antibody that blocks the N terminus of PSGL-1. Thus, multiple A. phagocytophilum isolates share the ability to use sLe^x-modified PSGL-1-dependent and -independent routes of entry into myeloid cells. HZA2 and HGE1A2 represent enriched bacterial populations that will aid dissection of the complexities of the interactions between A. phagocytophilum and host myeloid cells.

Published ahead of print on 24 September 2007.

Editor: A. J. Bäumler

Present address: Department of Molecular and Cellular Biochemistry, The Ohio State University, 366 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210-1218.

This article has been cited by other articles:

• Granick, J. L., Reneer, D. V., Carlyon, J. A., Borjesson, D. L. (2008). Anaplasma phagocytophilum infects cells of the megakaryocytic lineage through sialylated ligands but fails to alter platelet production. J Med Microbiol 57: 416-423 [Abstract] [Full Text]