title: Pharmacokinetics of posaconazole within epithelial cells and fungi: insights into potential mechanisms of action during treatment and prophylaxis.
abstract: BACKGROUND
  The antifungal posaconazole concentrates within host cells and protects against Aspergillus fumigatus. The specific subcellular location of posaconazole and the mechanism by which cell-associated posaconazole inhibits fungal growth remain uncharacterized.
  
  
  METHODS
  Posaconazole was conjugated with the fluorophore boron-dipyrromethene (BDP-PCZ). A549 pulmonary epithelial cells and A. fumigatus were exposed to BDP-PCZ individually and in coculture. BDP-PCZ subcellular localization and trafficking were observed using confocal microscopy and flow cytometry.
  
  
  RESULTS
  BDP-PCZ concentrated within A549 cell membranes, and in particular within the endoplasmic reticulum. Epithelial cell-associated BDP-PCZ rapidly transferred to and concentrated within A. fumigatus cell membranes on contact. BDP-PCZ transfer to conidia did not require phagocytosis and was markedly enhanced by the conidial hydrophobin RodA. Within AF, BDP-PCZ also concentrated in membranes including the endoplasmic reticulum and colocalized with the azole target enzyme CYP51a. Concentration of BDP-PCZ within host and fungal cell membranes persisted for >48 hours and could be competitively inhibited by posaconazole but not voriconazole.
  
  
  CONCLUSIONS
  Posaconazole concentrates within host cell membranes and rapidly transfers to A. fumigatus, where it accumulates to high concentrations and persists at the site of its target enzyme. These intracellular and intercellular pharmacokinetic properties probably contribute to the efficacy of PCZ.
authors.affiliation: Department of Microbiology and Immunology.
authors.forename: Paolo
authors.initials: P
authors.lastname: Campoli
authors.forename: David S
authors.initials: DS
authors.lastname: Perlin
authors.forename: Arnold S
authors.initials: AS
authors.lastname: Kristof
authors.forename: Theodore C
authors.initials: TC
authors.lastname: White
authors.forename: Scott G
authors.initials: SG
authors.lastname: Filler
authors.forename: Donald C
authors.initials: DC
authors.lastname: Sheppard
mesh_terms: D019072:Antibiotic Prophylaxis; D000935:Antifungal Agents / Q000378:metabolism* / Q000494:pharmacology / Q000627:therapeutic use; D001232:Aspergillus fumigatus / Q000187:drug effects / Q000378:metabolism; D001692:Biological Transport; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism*; D005658:Fungi / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D009181:Mycoses / Q000188:drug therapy / Q000517:prevention & control; D011485:Protein Binding; D013172:Spores, Fungal / Q000187:drug effects / Q000378:metabolism; D014230:Triazoles / Q000378:metabolism* / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D000935:Antifungal Agents; D014230:Triazoles; C101425:posaconazole
keywords: Aspergillus; endoplasmic reticulum; epithelial cells; hydrophobin rodA; localization; pharmacokinetics; posaconazole; postantifungal effect
references.citation: N Engl J Med. 2007 Jan 25;356(4):348-59
references.pmid: 17251531
references.citation: Antimicrob Agents Chemother. 2010 Oct;54(10):4143-9
references.pmid: 20660670
references.citation: Blood Rev. 2010 Mar;24(2):51-61
references.pmid: 20056300
references.citation: Semin Hematol. 2009 Jul;46(3):212-29
references.pmid: 19549575
references.citation: Antimicrob Agents Chemother. 2004 Feb;48(2):568-74
references.pmid: 14742211
references.citation: N Engl J Med. 2007 Jan 25;356(4):335-47
references.pmid: 17251530
references.citation: Antimicrob Agents Chemother. 2006 Jun;50(6):2009-15
references.pmid: 16723559
references.citation: Antimicrob Agents Chemother. 2011 Jul;55(7):3099-104
references.pmid: 21502622
references.citation: J Biol Chem. 2012 Apr 27;287(18):14325-35
references.pmid: 22399302
references.citation: Eukaryot Cell. 2009 Jan;8(1):104-15
references.pmid: 19028996
references.citation: Antimicrob Agents Chemother. 2011 May;55(5):2483-6
references.pmid: 21300838
references.citation: Antimicrob Agents Chemother. 2010 Sep;54(9):3609-13
references.pmid: 20516276
references.citation: Microbes Infect. 2009 Oct;11(12):919-27
references.pmid: 19615460
references.citation: Int J Antimicrob Agents. 2001 Nov;18(5):419-25
references.pmid: 11711255
references.citation: Antimicrob Agents Chemother. 2012 Jun;56(6):2806-13
references.pmid: 22391534
references.citation: Antimicrob Agents Chemother. 2011 Dec;55(12):5732-9
references.pmid: 21930891
references.citation: Curr Opin Microbiol. 2011 Aug;14(4):375-9
references.pmid: 21784698
references.citation: PLoS Negl Trop Dis. 2010 Apr 06;4(4):e651
references.pmid: 20386598
references.citation: Antimicrob Agents Chemother. 2009 Feb;53(2):703-7
references.pmid: 19029316
references.citation: Antimicrob Agents Chemother. 2004 Oct;48(10):3690-6
references.pmid: 15388421
references.citation: Infect Immun. 1994 Oct;62(10):4380-8
references.pmid: 7927699
references.citation: Antimicrob Agents Chemother. 2010 Jul;54(7):2928-31
references.pmid: 20457819
references.citation: Haematologica. 2012 Mar;97(3):459-63
references.pmid: 22058198
references.citation: J Antimicrob Chemother. 2007 Nov;60(5):1080-4
references.pmid: 17855727
references.citation: PLoS Pathog. 2010 Sep 30;6(9):e1001126
references.pmid: 20941354
references.citation: Mycopathologia. 2009 Dec;168(6):313-27
references.pmid: 19308672
references.citation: Blood. 2004 Mar 15;103(6):2143-9
references.pmid: 14630829
references.citation: Antimicrob Agents Chemother. 2010 Oct;54(10):4225-34
references.pmid: 20660663
references.citation: Med Mycol. 2013 Jan;51(1):103-7
references.pmid: 22587729