Evaluation of transfection effectiveness using fluorescein-labelled oligonucleotides and various liposomes

Silencing of genes using siRNA represents a generally used technique aimed at inhibiting expression of proteins in cells. Results have frequently not met expectations and this has posed problems in association with this technique. The phenomenon might reflect an incorrect sequence of RNAi, poor penetration of the cells by the nucleotides or insufficient knowledge of the protein in question. The present study is aimed at evaluating the effectiveness of the transfection of selected cell lines using various liposomes. The studies were performed using 9 cell lines: EPG 257/85 RNOV, EPG 257/85 RDB, W 181/A17, A 2780P, A 2780 RCIS, MEWO CIS, 181 RDB, 181 P and MCF-7/MX. The lines were transfected with fluorescently labelled oligonucleotides. Two parallel experiments were performed. In one oligofectamin and in the other DMRI were used as oligonucleotide carriers. The studies demonstrated that in every case nucleotides penetrated more than 90% of the cells. In 4 cell lines the signal was stronger when oligofectamin was used, in 4 cell lines when DMRI was employed and in one case the signal strength was comparable using any carrier. The studies showed that various liposomes demonstrated distinct transfection efficiency, depending on the cell line used, and that application of fluorescently labelled nucleotides may be helpful in the optimisation of transfection conditions.