Figure 3

C3 binding to clinical isolates of pathogenic species and mutant S. aureus in elevated glucose. (A) Purified C3 binding to 8 clinical S. aureus isolates was increased in 17 mmol/l glucose (black bars) compared with 3 mmol/l glucose (grey bars). Four strains are MRSA (MR) and four strains are methicillin-susceptible (SA). Data are mean ± SE for 3 independent experiments for each isolate. Strain Reynolds was used as a control. (B) Purified C3 binding to a sortase-deficient S. aureus strain (Sortase-) and an isogenic control was similarly increased in 17 mmol/l glucose (black bars) compared with 3 mmol/l glucose (grey bars). Data are mean ± SE for 3 independent experiments. (C) Purified C3 binding to 15 clinical Gram-negative isolates in PBS with 3 mmol/l glucose (grey bars) or 17 mmol/l glucose (black bars). Three isolates were tested for each species; data are mean ± SE.