Cholesterol as treatment for pneumococcal keratitis: cholesterol-specific inhibition of pneumolysin in the cornea.

Purpose: The purpose of this study was to determine whether cholesterol, the host cell receptor for pneumolysin of Streptococcus pneumoniae, could effectively treat pneumococcal keratitis.

Methods: New Zealand White rabbits were intrastromally injected with 10(5) colony-forming units (CFUs) of S. pneumoniae D39.

The effectiveness of lysostaphin therapy for experimental coagulase-negative Staphylococcus endophthalmitis.

Purpose: To quantitatively determine the effectiveness of lysostaphin therapy for experimental endophthalmitis mediated by coagulase-negative Staphylococcus species, the leading cause of postsurgical endophthalmitis.

Methods: Minimal inhibitory concentrations (MIC) of lysostaphin were determined for 54 isolates representing the following species: S. epidermidis, S.

Effects of toxin production in a murine model of Staphylococcus aureus keratitis.

Purpose: To investigate the corneal virulence of toxin-deficient mutants of Staphylococcus aureus in young and aged mice in a topical inoculation model of keratitis.

Methods: Corneas of young and aged A/J mice were scarified and topically inoculated with a log phase S. aureus parent strain (8325-4), an alpha-toxin-deficient mutant (DU1090), or an Agr-defective mutant (ISP546) deficient in production of multiple toxins or with purified alpha-toxin.

Pathogenesis of Staphylococcus in the rabbit anterior chamber.

Purpose: To investigate the host defense against Staphylococcus in the rabbit anterior chamber.

Methods: The bactericidal activity of rabbit aqueous humor was investigated in vitro. Rabbit anterior chambers were injected with viable Staphylococcus aureus or Staphylococcus epidermidis (1,000 or 500,000 colony-forming units [CFU]), killed bacteria, culture supernatants of either organism, or purified S.

Ocular virulence of capsule-deficient streptococcus pneumoniae in a rabbit keratitis model.

Purpose: Determine the ocular virulence of noncapsular Streptococcus pneumoniae in a rabbit keratitis model.

Methods: Mice were infected intraperitoneally with 10(5) colony-forming units (CFUs) of Avery's strain (capsular type 2) or strain R6 (a noncapsular derivative of type 2), and mortality was monitored daily. In addition, 10(5) CFU of each strain was injected into rabbit corneas.

Susceptibility of aged mice to Staphylococcus aureus keratitis.

Purpose: To determine the effect of age on the extent of pathogenesis of Staphylococcus keratitis in the mouse.

Methods: Corneas of young and aged mice (BALB/c, A/J, and C57BL/6) were scarified and topically inoculated with S. aureus.

A new topical model of Staphylococcus corneal infection in the mouse.

Purpose: To establish, in the scarified mouse eye, a new model of Staphylococcus aureus keratitis suitable for studies of pathogenesis and host defense mechanisms.

Methods: Corneas of three strains of mice (BALB/c, A/J, and C57BL/6) were scarified and inoculated with S. aureus strain 8325-4.