Figure 4. Numbers of bacteria (cfu) killed by macrophages (J774.2 cell line) following 1 h co-incubation with S. pyogenes MGAS6180 or MGAS10270 wild type and aspA mutants (input 5×10³ cfu, 5×10⁴ macrophages).

Percentage killing was calculated from cfu remaining compared with control samples without macrophages. Data are means ± SEM of 3 experiments repeated in triplicate. * = P<0.001 using 2 tail student T-test.