title: Opsonizing effect of normal cerebrospinal fluid on Staphylococcus aureus.
abstract: The opsonizing effect of normal cerebrospinal fluid (CSF) on Staphylococcus aureus has been demonstrated through phagocytic assay. Radiolabelled S. aureus was opsonized using various CSF preparations and then ingested by neutrophils. Uptake of S. aureus by neutrophils was 31 +/- 12% for untreated CSF, 28 +/- 14% for ethylene-glycol-bis(beta-aminoethyl ether) -N,N-tetraacetic acid(EGTA) chelation, 18 +/- 5% for heat-treated (50 degrees C), 14 +/- 8% for heat-inactivated (56 degrees C), 11 +/- 6% for S. aureus-absorbed, and 5 +/- 4% for heat-inactivated and S. aureus-absorbed, respectively. Indirect immunofluorescence antibody assay revealed that IgG was the class of immunoglobulins involved in the opsonic activity of CSF, and complement 3 (C3) deposition was weakly detected in S. aureus. These results suggest that both heat-labile (complement) and heat-stable (antibody) factors are crucial for the opsonization of S. aureus by normal CSF. We conclude that activation of the complement by S. aureus in normal CSF is through an alternative pathway and is enhanced by the presence of a specific antibody (IgG).
authors.affiliation: Department of Parasitology, National Defense Medical Center, Taipei, Taiwan, R.O.C.
authors.forename: S C
authors.initials: SC
authors.lastname: Hou
authors.forename: S T
authors.initials: ST
authors.lastname: Ho
authors.forename: M F
authors.initials: MF
authors.lastname: Shaio
mesh_terms: D002555:Cerebrospinal Fluid / Q000276:immunology*; D003176:Complement C3 / Q000502:physiology; D006801:Humans; D007074:Immunoglobulin G / Q000502:physiology; D009504:Neutrophils / Q000276:immunology*; D009895:Opsonin Proteins / Q000502:physiology*; D010587:Phagocytosis; D013211:Staphylococcus aureus
chemical_list: D003176:Complement C3; D007074:Immunoglobulin G; D009895:Opsonin Proteins