Fig. 12. Immunocytochemical labelling of SR-BI in Caco-2 cells following antisense treatment. To confirm the disruption of SR-BI expression using SR-BI antisense oligodeoxynucleotides, we applied the immunogold protein A technique on Caco-2 cells transfected with the vector pZeoSV without insert (A) or with the human SR-BI cDNA inserted in an antisense orientation (B). Upper panels show the apical region of the cell, and lower panels illustrate the basolateral region of the cell. Reduced labelling is noticed in microvilli (mv) and the basolateral membrane as well as within endocytotic vesicles (arrows). Magnification: A, upper panel x38,000; lower panel x36,000; B, upper panel x40,000; lower panel x56,000.