CK18 expression on RNAi-treated HeLa cells. (A) HeLa cells were left untreated (Medium) or transfected with the CK18 or control RNAi as described in the Methods section. CK18 transcripts were estimated by Real-time PCR. Results are expressed in arbitrary units after normalization with RPL13 transcritps. Results are represented as an average of triplicate samples ± SD. The experiments were performed three times with similar results. (B) Immunoblot analysis of HeLa cells extracts untreated (Medium) or treated with CK18 or control RNAi. Stainings were performed with MAbs specific for CK18 or β-actin. (C) Densitometry of immunoblot was performed and the bars represent the absorbance of CK18 bands after normalization using the staining with anti-β-actin. (D) IFA staining of HeLa cells untreated (Medium) or treated with CK18 or control RNAi. HeLa cells were treated with RNAi for 24 h and infected with tissue culture trypomastigotes for 48 h. After that period, cells were stained with a MAbs specific for CK18 (green) and DAPI (blue). Magnification bar = 35 μM.