title: Drug transporter expression in human macrophages.
abstract: Macrophages represent major cellular targets of various drugs, especially antibiotics and anti-viral drugs. Factors that may govern intracellular accumulation of drugs in these cells, especially those related to activity of drug transporters, are consequently likely important to consider. The present study was therefore designed to extensively characterize expression of solute carrier (SLC) and ATP-binding cassette (ABC) transporters in primary human macrophages generated from blood monocytes. Using quantitative polymerase chain reaction assays, these cells were found to exhibit very high or high levels of mRNA expression of concentrative nucleoside transporter (CNT) 3, equilibrative nucleoside transporter 3, monocarboxylate transporter (MCT) 1, MCT4, peptide/histidine transporter (PHT) 1, PHT2, organic anion transporting polypeptide transporter 2B1 and ABC pumps multidrug resistance protein (MRP) 1/ABCC1 and MRP3/ABCC3. By contrast, other transporters, including the efflux pump ABCB1/P-glycoprotein, were found at lower levels or were not expressed. Concomitantly, human macrophages displayed notable uptake of the MCT substrate lactate and of the CNT substrate uridine and also exhibited cellular efflux of the MRP substrate carboxy-2',7'-dichlorofluorescein. Such a functional expression of these transporters has likely to be considered with respect to cellular pharmacokinetics of drugs targeting macrophages.
authors.affiliation: EA 4427 Signalisation et Réponse aux Agents Infectieux et Chimiques, Institut de Recherches en Santé, Environnement et Travail, Université de Rennes 1, 2 avenue du Pr Léon Bernard, 35043 Rennes, France.
authors.forename: Amélie
authors.initials: A
authors.lastname: Moreau
authors.forename: Marc
authors.initials: M
authors.lastname: Le Vee
authors.forename: Elodie
authors.initials: E
authors.lastname: Jouan
authors.forename: Yannick
authors.initials: Y
authors.lastname: Parmentier
authors.forename: Olivier
authors.initials: O
authors.lastname: Fardel
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D001692:Biological Transport; D002352:Carrier Proteins / Q000235:genetics*; D002478:Cells, Cultured; D005452:Fluoresceins / Q000493:pharmacokinetics; D015870:Gene Expression; D006801:Humans; D019344:Lactic Acid / Q000493:pharmacokinetics; D008264:Macrophages / Q000378:metabolism*; D012313:RNA; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D018528:ATP-Binding Cassette Transporters; D002352:Carrier Proteins; D005452:Fluoresceins; C034477:RNA primers; D012333:RNA, Messenger; C053897:5(6)-carboxy-2',7'-dichlorofluorescein; D019344:Lactic Acid; D012313:RNA