Bacterial killing by complement requires direct anchoring of membrane attack complex precursor C5b-7
Fig 5
The presence of C7 during the generation of C5b6 results in more efficient recruitment of C9.
Convertase-labelled E. coli MG1655 was treated as in Fig 3A in which C5b6 was formed for 60 minutes in the absence (red circles) or presence (blue squares) of C7 after which C8 and C9 were added and bacteria were analyzed by flow cytometry after 30 minutes. Deposition of C9-Cy5 (A) and C6-Cy5 (B) were both measured in parallel experiments and represented as geoMFI of the bacterial population. The fluorescence ratio between C9:C6 (C) was calculated by dividing the geoMFI of C9 by the geoMFI of C6. Data represent individual samples with mean +- SD of at least 3 independent experiments. Statistical analysis was done using a paired two-tailed t-test (A-C). Significance was shown as * p ≤ 0.05 or *** p ≤ 0.001.