Figure 1. dsRNA-mediated silencing of the B. malayi cathepsin-like genes, Bm-cpl-1, Bm-cpl-5, and Bm-cpz leads to a reduction in microfilaria release from B. malayi in vitro.

Following 24 h culture in normal culture medium, two groups of 3 female B. malayi worms were soaked for 18 h in 2 mg/ml gene-specific dsRNA (Bm-cpl-1, Bm-cpl-5, Bm-cpz, Ov-cpz-Int2) or medium alone (control). Following dsRNA treatment, individual worms were transferred to dsRNA-free medium and cultured for an additional 48 h. Released microfilariae were collected and counted daily. Results are expressed as Mf release before RNAi treatment (A), 24 h (B) and 48 h (C) after treatment. Each graph represents one experiment which is representative of at least 3 separate experiments. P values denote a significant difference between dsRNA-treated worms and either untreated medium controls or negative control (Ov-cpz-Int2) (Mann-Whitney U-test).