Title: | Enterococcus faecalis aggregation substance promotes opsonin-independent binding to human neutrophils via a complement receptor type 3-mediated mechanism |
Author(s): | Vanek NN; Simon SI; Jacques-Palaz K; Mariscalco MM; Dunny GM; Rakita RM; |
Address: | "Division of Infectious Diseases, Department of Internal Medicine and Center for the Study of Emerging and Reemerging Pathogens, University of Texas Medical School, Houston, TX 77030, USA" |
Journal Title: | FEMS Immunol Med Microbiol |
DOI: | 10.1111/j.1574-695X.1999.tb01371.x |
ISSN/ISBN: | 0928-8244 (Print) 0928-8244 (Linking) |
Abstract: | "Enterococcus faecalis aggregation substance (AS) mediates efficient adhesion between bacteria, thereby facilitating plasmid exchange as an integral part of a bacterial sex pheromone system. We examined the interaction of AS-bearing E. faecalis with human neutrophils (PMNs), an important component of the host defense system. AS promoted a markedly increased opsonin-independent bacterial binding to PMNs. Adhesion was dependent on the expression of the enterococcal Asc10 protein, which contains two Arg-Gly-Asp (RGD) sequences, and addition of exogenous RGD-containing peptides inhibited AS-mediated binding by 66%. AS-mediated adhesion was inhibited by 85% by anti-human complement receptor type 3 (CR3) monoclonal antibodies or by use of PMNs from a patient with leukocyte adhesion deficiency. However, AS-bearing E. faecalis cells were unable to bind to CHO-Mac-1 cells, expressing functionally active CR3, suggesting the potential need for additional PMN surface receptors for bacterial adhesion. Monoclonal antibodies against integrin-associated protein (CD47) and L-selectin, both of which may interact with CR3 and bind to ligands on E. faecalis, also inhibited AS-dependent binding. The non-opsonic binding of E. faecalis to PMNs may play an important role in this organism's pathogenesis" |
Keywords: | "Adhesins, Bacterial/*physiology Animals Antibodies, Monoclonal/immunology/pharmacology Antigens, CD/immunology Bacterial Adhesion/drug effects Bacterial Proteins/immunology CD47 Antigen CHO Cells Carrier Proteins/immunology Cricetinae Dose-Response Relati;" |
Notes: | "MedlineVanek, N N Simon, S I Jacques-Palaz, K Mariscalco, M M Dunny, G M Rakita, R M eng AI19031/AI/NIAID NIH HHS/ AI31652/AI/NIAID NIH HHS/ HL51987/HL/NHLBI NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. England 1999/10/13 FEMS Immunol Med Microbiol. 1999 Oct; 26(1):49-60. doi: 10.1111/j.1574-695X.1999.tb01371.x" |