Different Effects of Fibronectin on the Phagocytosis of Staphylococcus aureus and Coagulase-Negative Staphylococci by Murine Peritoneal Macrophages

• Published in: MICROBIOLOGY and IMMUNOLOGY 1998, Vol.42(12), pp.851-861
• Main Authors: Shinji, Hitomi, Sakurada, Junji, Seki, Keiko, Murai, Miyo, Masuda, Shogo
• Format: Article
• Language: English
• Subjects: Adhesins, Bacterial; Animals; Bacterial Proteins - genetics; Bacterial Proteins - immunology; Bacteriology; Biological and medical sciences; Carrier Proteins - genetics; Carrier Proteins - immunology; Coagulase; Culture Media; Female; Fibronectin; Fibronectins - immunology; Fundamental and applied biological sciences. Psychology; Macrophage; Macrophages, Peritoneal - immunology; Mice; Mice, Inbred ICR; Microbiology; Pathogenicity, virulence, toxins, bacteriocins, pyrogens, host-bacteria relations, miscellaneous strains; Phagocytosis; Phagocytosis - immunology; Serum Albumin, Bovine; Staphylococci; Staphylococcus aureus; Staphylococcus aureus - genetics; Staphylococcus aureus - immunology
• ISSN: 0385-5600; 1348-0421
• DOI: 10.1111/j.1348-0421.1998.tb02361.x

Fibronectin is known to be an important factor in colonization by Staphylococcus aureus of host tissues as well as other extracellular matrix proteins such as collagen and laminin. We investigated the effect of fibronectin on the phagocytosis of the S. aureus Cowan I strain by macrophages and of coagulase-negative staphylococci (CNS) strains for comparison. Fibronectin-reduced serum in place of normal serum lowered the phagocytic activity of the macrophages on the Cowan I strain. Purified fibronectin enhanced the phagocytic activity of the strain in a dose-dependent manner. On the other hand, fibronectin did not show any opsonic effect on the ingestion of CNS strains, though the binding of fibronectin occurred equally well in CNS strains and the Cowan I strain. Fibronectin-binding protein (FnBP), the specific fibronectin receptor on the surface on S. aureus, was detected in both the Cowan I strain and CNS strains. Polymerase chain reaction confirmed that not only the Cowan I strain, but also CNS strains possessed the FnBP gene. These results indicate that fibronectin shows an opsonic effect on the S. aureus, Cowan I strain but not on CNS strains, and suggest that the binding of fibronectin to FnBP is not sufficient for efficient phagocytosis of the staphylococci strains by macrophages.