The Impact of Endogenous Breast Cancer Resistance Protein on Human P-Glycoprotein-Mediated Transport Assays Using LLC-PK1 Cells Transfected With Human P-Glycoprotein.

Lilly Laboratories cell porcine kidney 1 (LLC-PK1) cells transfected with human P-glycoprotein (LLC-PK1-P-gp) are widely used in transport assays to identify drug candidates that function as substrates of this efflux transporter. Endogenous transporters expressed in LLC-PK1 cells may complicate the interpretation of findings from P-gp-mediated transport assays. We investigated the impact of porcine breast cancer resistance protein (Bcrp) in P-gp-mediated transport assays in LLC-PK1 cells.

Development and validation of semiautomated 96-well transport assay using LLC-PK1 cells transfected with human P-glycoprotein for high-throughput screening.

Transport assays using P-gp-expressing cell lines are commonly used to identify P-gp substrates and inhibitors in drug discovery. The P-gp cell-based assay is performed manually in 12- or 24-well plates and requires improvement for high-throughput screening. In this study, we established an efficient semiautomated 96-well transport assay using LLC-PK1 cells transfected with human P-gp.

Enhanced target-specific accumulation of radiolabeled antibodies by conjugating arginine-rich peptides as anchoring molecules.

We have devised and estimated a new strategy to prolong the residence time of radiolabeled antibodies in tumor in which an octaarginine peptide (R₈) was used as an anchoring molecule to fix antibodies against CD20 (NuB2; IgG2a) on tumor cells. Conjugation of R₈ with antibodies was performed by maleimide-thiol chemistry using thiol groups generated by reducing the disulfide bonds of the antibody. The R₈-conjugated NuB2 was then reacted with succinimidyl meta-[¹²⁵I]iodobenzoate to prepare [¹²⁵I]SIB-NuB2(I) (0.