title: Human immunodeficiency virus protease inhibitors serve as substrates for multidrug transporter proteins MDR1 and MRP1 but retain antiviral efficacy in cell lines expressing these transporters.
abstract: The human immunodeficiency virus type 1 (HIV-1) protease inhibitors (PIs)-saquinavir, ritonavir, nelfinavir, and indinavir-interact with the ABC-type multidrug transporter proteins MDR1 and MRP1 in CEM T-lymphocytic cell lines. Calcein fluorescence was significantly enhanced in MDR1(+) CEM/VBL100 and MRP1(+) CEM/VM-1-5 cells incubated in the presence of various HIV PIs and calcein acetoxymethyl ester. HIV PIs also enhanced the cytotoxic activity of doxorubicin, a known substrate for MDR1 and MRP1, in both VBL100 and VM-1-5 CEM lines. Saquinavir, ritonavir, and nelfinavir enhanced doxorubicin toxicity in CEM/VBL100 cells by approximately three- to sevenfold. Saquinavir and ritonavir also enhanced doxorubicin toxicity in CEM/VM-1-5 cells. HIV-1 replication was effectively inhibited by the various PIs in all of the cell lines, and the 90% inhibitory concentration for a given compound was comparable between the different cell types. Therefore, overexpression of MDR1 or MRP1 by T lymphocytes is not likely to limit the antiviral efficacy of HIV PI therapy.
authors.affiliation: Department of Infectious Diseases, St. Jude Children's Research Hospital, Memphis, Tennessee, USA. ranga.srinivas@stjude.org
authors.forename: R V
authors.initials: RV
authors.lastname: Srinivas
authors.forename: D
authors.initials: D
authors.lastname: Middlemas
authors.forename: P
authors.initials: P
authors.lastname: Flynn
authors.forename: A
authors.initials: A
authors.lastname: Fridland
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000096:biosynthesis / Q000378:metabolism*; D018528:ATP-Binding Cassette Transporters / Q000096:biosynthesis / Q000378:metabolism*; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D000998:Antiviral Agents / Q000378:metabolism / Q000494:pharmacology*; D002460:Cell Line; D004317:Doxorubicin / Q000494:pharmacology; D004352:Drug Resistance, Microbial; D018432:Drug Resistance, Multiple; D005434:Flow Cytometry; D005452:Fluoresceins; D005456:Fluorescent Dyes; D017320:HIV Protease Inhibitors / Q000378:metabolism / Q000494:pharmacology*; D015497:HIV-1 / Q000187:drug effects; D006801:Humans; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D013601:T-Lymphocytes / Q000187:drug effects / Q000382:microbiology
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D018528:ATP-Binding Cassette Transporters; D000903:Antibiotics, Antineoplastic; D000998:Antiviral Agents; D004317:Doxorubicin; D005452:Fluoresceins; D005456:Fluorescent Dyes; D017320:HIV Protease Inhibitors; D027425:ATP-Binding Cassette, Sub-Family C Proteins; C085925:calcein AM