title: Functional Validation of ABCA3 as a Miltefosine Transporter in Human Macrophages: IMPACT ON INTRACELLULAR SURVIVAL OF LEISHMANIA (VIANNIA) PANAMENSIS.
abstract: Within its mammalian host, Leishmania resides and replicates as an intracellular parasite. The direct activity of antileishmanials must therefore depend on intracellular drug transport, metabolism, and accumulation within the host cell. In this study, we explored the role of human macrophage transporters in the intracellular accumulation and antileishmanial activity of miltefosine (MLF), the only oral drug available for the treatment of visceral and cutaneous leishmaniasis (CL). Membrane transporter gene expression in primary human macrophages infected in vitro with Leishmania Viannia panamensis and exposed to MLF showed modulation of ABC and solute liquid carrier transporters gene transcripts. Among these, ABCA3, a lipid transporter, was significantly induced after exposure to MLF, and this induction was confirmed in primary macrophages from CL patients. Functional validation of MLF as a substrate for ABCA3 was performed by shRNA gene knockdown (KD) in THP-1 monocytes. Intracellular accumulation of radiolabeled MLF was significantly higher in ABCA3(KD) macrophages. ABCA3(KD) resulted in increased cytotoxicity induced by MLF exposure. ABCA3 gene expression inversely correlated with intracellular MLF content in primary macrophages from CL patients. ABCA3(KD) reduced parasite survival during macrophage infection with an L. V. panamensis strain exhibiting low in vitro susceptibility to MLF. Confocal microscopy showed ABCA3 to be located in the cell membrane of resting macrophages and in intracellular compartments in L. V. panamensis-infected cells. These results provide evidence of ABCA3 as an MLF efflux transporter in human macrophages and support its role in the direct antileishmanial effect of this alkylphosphocholine drug.
authors.affiliation: From the Centro Internacional de Entrenamiento e Investigaciones Médicas, Cra. 125 # 19-225 Cali, Colombia, the Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3508 TB Utrecht, The Netherlands.
authors.forename: Luuk C T
authors.initials: LC
authors.lastname: Dohmen
authors.affiliation: From the Centro Internacional de Entrenamiento e Investigaciones Médicas, Cra. 125 # 19-225 Cali, Colombia.
authors.forename: Adriana
authors.initials: A
authors.lastname: Navas
authors.affiliation: From the Centro Internacional de Entrenamiento e Investigaciones Médicas, Cra. 125 # 19-225 Cali, Colombia.
authors.forename: Deninson Alejandro
authors.initials: DA
authors.lastname: Vargas
authors.affiliation: the Molecular and Integrative Physiological Sciences, Harvard T. H. Chan School of Public Health, Boston, Massachusetts 02115.
authors.forename: David J
authors.initials: DJ
authors.lastname: Gregory
authors.affiliation: the Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3508 TB Utrecht, The Netherlands, the Department of Pharmacy and Pharmacology, Antoni van Leeuwenhoek Hospital/Slotervaart Hospital, 1066 CX Amsterdam, The Netherlands, and.
authors.forename: Anke
authors.initials: A
authors.lastname: Kip
authors.affiliation: the Division of Pharmacoepidemiology and Clinical Pharmacology, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3508 TB Utrecht, The Netherlands, the Department of Pharmaceutical Biosciences, Uppsala University, 751 24 Uppsala, Sweden.
authors.forename: Thomas P C
authors.initials: TP
authors.lastname: Dorlo
authors.affiliation: From the Centro Internacional de Entrenamiento e Investigaciones Médicas, Cra. 125 # 19-225 Cali, Colombia, mgomez@cideim.org.co.
authors.forename: Maria Adelaida
authors.initials: MA
authors.lastname: Gomez
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D001693:Biological Transport, Active / Q000187:drug effects / Q000235:genetics; D045744:Cell Line, Tumor; D055785:Gene Knockdown Techniques; D006801:Humans; D007891:Leishmania / Q000235:genetics / Q000378:metabolism*; D007896:Leishmaniasis / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D008264:Macrophages / Q000378:metabolism* / Q000469:parasitology* / Q000473:pathology; D010767:Phosphorylcholine / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000494:pharmacology
chemical_list: C441524:ABCA3 protein, human; D018528:ATP-Binding Cassette Transporters; D010767:Phosphorylcholine; C039128:miltefosine
keywords: ABC transporter; ABCA3; Leishmania; drug transport; host-pathogen interaction; macrophage; miltefosine; pharmacodynamics