Fig. 1.

Functional analysis of various deletion constructs in response to Lactobacillus acidophilus (LA) culture supernatant (CS). Caco-2 cells were transiently transfected with different 5′-deletion constructs of P-glycoprotein (Pgp) promoter along with p-cytomegalovirus (CMV) β-galactosidase (pCMVβ) vector. At 24 h posttransfection, cells were treated with a 1:10 dilution of LA CS for 24 h in medium containing 1% FBS. Cells were harvested at 48 h posttransfection, and promoter activity was measured by luciferase (Luc) assay. Data were normalized to β-galactosidase activity to correct for transfection efficiency. Values are means ± SE of 4 separate experiments and are expressed as percentage of control [i.e., transfected cells treated with LA CS vs. untreated cells (control)]. *P < 0.05 vs. respective control.