Generation and complementation of <i>12940</i> null <i>T</i>. <i>b</i>. <i>brucei</i>.

<p>(A) Southern blot confirming <i>Tb927</i>.<i>10</i>.<i>12940</i> deletion; <i>BSD</i>, blasticidin-S-deaminase; <i>NPT</i>, neomycin phosphotransferase. Schematic showing segment deleted from the <i>Tb927</i>.<i>10</i>.<i>12940</i> locus (open triangle); positions of <i>Sal</i>I restriction sites (arrowheads), deletion (12940) and flanking (DS) probes highlighted. (B) Cumulative growth of wild type and three independent <i>12940</i> null <i>T</i>. <i>b</i>. <i>brucei</i> cell lines; error bars showing standard deviation are smaller than the plot symbols. (C, D) Representative EC₅₀ assays carried out in quadruplicate showing the impact of (C) <i>Tb927</i>.<i>10</i>.<i>12940</i> deletion and (D) re-expression on apoL1 sensitivity. Insets, pooled EC₅₀ data for at least two independent cell lines. (E, F) Kinetic analyses of parasite killing in 10 μg.ml^-1 apoL1 following (E) <i>Tb927</i>.<i>10</i>.<i>12940</i> deletion and (F) re-expression; each assay was carried out using three independent cell lines, re-expression was induced in 1 μg.ml^-1 tetracycline for 24 hours prior to exposure to apoL1. Error bars, standard deviation; <i>P</i>-values derived from paired students t-test.