title: An Fc-Small Molecule Conjugate for Targeted Inhibition of the Adenosine 2A Receptor.
abstract: The adenosine A2Areceptor (A2AR) is expressed in immune cells, as well as brain and heart tissue, and has been intensively studied as a therapeutic target for multiple disease indications. Inhibitors of the A2AR have the potential for stimulating immune response, which could be valuable for cancer immune surveillance and mounting a response against pathogens. One well-established potent and selective small molecule A2AR antagonist, ZM-241385 (ZM), has a short pharmacokinetic half-life and the potential for systemic toxicity due to A2AR effects in the brain and the heart. In this study, we designed an analogue of ZM and tethered it to the Fc domain of the immunoglobulin IgG3 by using expressed protein ligation. The resulting protein-small molecule conjugate, Fc-ZM, retained high affinity for two Fc receptors: FcγRI and the neonatal Fc receptor, FcRn. In addition, Fc-ZM was a potent A2AR antagonist, as measured by a cell-based cAMP assay. Cell-based assays also revealed that Fc-ZM could stimulate interferon γ production in splenocytes in a fashion that was dependent on the presence of A2AR. We found that Fc-ZM, compared with the small molecule ZM, was a superior A2AR antagonist in mice, consistent with the possibility that Fc attachment can improve pharmacokinetic and/or pharmacodynamic properties of the small molecule.
authors.affiliation: Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 302 Wood Basic Science Building, 725 N Wolfe St., Baltimore, MD, 21205, USA.
authors.forename: Po-Yuan
authors.initials: PY
authors.lastname: Hsiao
authors.affiliation: Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 302 Wood Basic Science Building, 725 N Wolfe St., Baltimore, MD, 21205, USA.
authors.forename: Jay H
authors.initials: JH
authors.lastname: Kalin
authors.affiliation: Sidney-Kimmel Comprehensive Cancer Research Center, Department of Oncology, Johns Hopkins School of Medicine, The Harry and Jeanette Weinberg Building, Ste. 1100, 401 N. Broadway, Baltimore, MD, 21205, USA.
authors.forename: Im-Hong
authors.initials: IH
authors.lastname: Sun
authors.affiliation: Department of Chemistry and Biochemistry, University of Maryland, 8051 Regents Drive, College Park, MD, 20742-4454, USA.|Center for Vaccine Development, University of Maryland, School of Medicine, 685 West Baltimore Street, Baltimore, MD, 21201-1509, USA.
authors.forename: Mohammed N
authors.initials: MN
authors.lastname: Amin
authors.affiliation: Sidney-Kimmel Comprehensive Cancer Research Center, Department of Oncology, Johns Hopkins School of Medicine, The Harry and Jeanette Weinberg Building, Ste. 1100, 401 N. Broadway, Baltimore, MD, 21205, USA.|Department of Pathology, Yale School of Medicine, 310 Cedar Street, LH 108, New Haven, CT, 06520-8023, USA.
authors.forename: Ying-Chun
authors.initials: YC
authors.lastname: Lo
authors.affiliation: Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 302 Wood Basic Science Building, 725 N Wolfe St., Baltimore, MD, 21205, USA.|Division of Viral Products, Office of Vaccines Research and Review, Center for Biologics Evaluation and Research, U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, MD, 20993, USA.
authors.forename: Meng-Jung
authors.initials: MJ
authors.lastname: Chiang
authors.affiliation: Department of Chemistry and Biochemistry, University of Maryland, 8051 Regents Drive, College Park, MD, 20742-4454, USA.
authors.forename: John
authors.initials: J
authors.lastname: Giddens
authors.affiliation: Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University, 601 N Caroline St., Baltimore, MD, 21287, USA.
authors.forename: Polina
authors.initials: P
authors.lastname: Sysa-Shah
authors.affiliation: Department of Molecular and Comparative Pathobiology, Johns Hopkins School of Medicine, 733 North Broadway, Miller Research Building, Room 807, Baltimore, MD, 21205-2196, USA.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Gabrielson
authors.affiliation: Department of Chemistry and Biochemistry, University of Maryland, 8051 Regents Drive, College Park, MD, 20742-4454, USA.
authors.forename: Lai-Xi
authors.initials: LX
authors.lastname: Wang
authors.affiliation: Sidney-Kimmel Comprehensive Cancer Research Center, Department of Oncology, Johns Hopkins School of Medicine, The Harry and Jeanette Weinberg Building, Ste. 1100, 401 N. Broadway, Baltimore, MD, 21205, USA.
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Powell
authors.affiliation: Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, 302 Wood Basic Science Building, 725 N Wolfe St., Baltimore, MD, 21205, USA. pcole1@jhmi.edu.
authors.forename: Philip A
authors.initials: PA
authors.lastname: Cole
mesh_terms: D058917:Adenosine A2 Receptor Antagonists / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D005260:Female; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000737:chemistry / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008958:Models, Molecular; D015394:Molecular Structure; D043705:Receptor, Adenosine A2A / Q000172:deficiency / Q000378:metabolism*; D012141:Respiratory Tract Infections / Q000188:drug therapy; D014227:Triazines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D014230:Triazoles / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D014616:Vaccinia virus / Q000302:isolation & purification
chemical_list: D058917:Adenosine A2 Receptor Antagonists; D007140:Immunoglobulin Fab Fragments; D043705:Receptor, Adenosine A2A; D014227:Triazines; D014230:Triazoles; C097270:ZM 241385
keywords: Fc domain; adenosine receptors; drug design; inhibitors; small molecules