Effect on polymorphonuclear cell function of a human-specific cytotoxin, intermedilysin, expressed by Streptococcus intermedius

• Published in: Infection and immunity Vol. 69; no. 10; pp. 6102 - 6109
• Main Authors: MACEY, M. G, WHILEY, R. A, MILLER, L, NAGAMUNE, H
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for Microbiology 01-10-2001
• Subjects: Bacterial Proteins; Bacterial Toxins - pharmacology; Bacteriocins; Bacteriology; Biological and medical sciences; Calcium - metabolism; CD11b antigen; Cell Fusion; Cell Membrane Permeability; Cell Size; Chemotaxis, Leukocyte - immunology; Cytotoxins - pharmacology; Flow Cytometry - methods; Fundamental and applied biological sciences. Psychology; Genetics; Hemolysis; Host Response and Inflammation; Humans; intermedilysin; Intracellular Fluid - metabolism; Leukocyte Count; Macrophage-1 Antigen - biosynthesis; Microbiology; Neutrophils - cytology; Neutrophils - drug effects; Neutrophils - immunology; Neutrophils - metabolism; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Phagocytosis - immunology; Staphylococcus aureus - immunology; Streptococcus; Streptococcus intermedius; Human; Opportunistic infection; Temperature; Cytolysin; Granulocyte; Red blood cell; Environmental factor; Electron microscopy; Inorganic element; Infection; Streptococcaceae; Blood cell; Specificity; Association; Flora; Pathogenic; Streptococcal infection; Streptococcus A; Bacteriosis; Bacteria; Micrococcales; Membrane; Membrane pore; Neutrophil
• ISSN: 0019-9567; 1098-5522
• DOI: 10.1128/IAI.69.10.6102-6109.2001

Streptococcus intermedius is a member of the normal flora of the mouth but is also an opportunistic pathogen associated with purulent infections at oral and nonoral sites. Intermedilysin (ILY) has been shown to be a cytolysin capable of generating pores in the cell membrane of erythrocytes demonstrable by electron microscopy. This effect has been shown to be specific for human cells. Since polymorphonuclear cells (PMNs) are the main cell involved in innate immunity we investigated the effect of purified intermedilysin from Streptococcus intermedius on PMN function. Active ILY at a concentration of 40 ng/microl caused a significant decrease in the number of intact PMNs after 60 min. The active cytolysin, when compared with heat-inactivated ILY, did not appear to be chemotactic for the PMNs but did cause an increase in intracellular calcium, with increased cell surface CD11b expression, metabolic burst, and phagocytosis of Staphylococcus aureus. These findings may have implications for the role of ILY in deep-seated abscesses.