title: Fine Tuning Antibody Conjugation Methods using SNAP-tag Technology.
abstract: BACKGROUND
  Targeted imaging and therapy (theranostics) is a promising approach for the simultaneous improvement of cancer diagnosis, prognosis and management. Therapeutic and imaging reagents are coupled to tumor-targeting molecules such as antibodies, providing a basis for truly personalized medicine. However, the development of antibody-drug conjugates with acceptable pharmaceutical properties is a complex process and several parameters must be optimized, such as the controlled conjugation method and the drug-to-antibody ratio.
  
  
  OBJECTIVE
  The major aim of this work is to address fundamental key challenges for the development of versatile technology platform for generating homogenous immunotheranostic reagent.
  
  
  METHODS
  We conjugated the theranostics reagent IRDye700dx to a recombinant antibody fusion protein containing a self-labeling protein (SNAP-tag) which provides a unique reaction site.
  
  
  RESULTS
  The resulting conjugate was suitable for the imaging of cancer cells expressing the epidermal growth factor receptor and demonstrated potent phototherapeutic and imaging activities against them.
  
  
  CONCLUSIONS
  Here, we describe a simple, rapid and robust site-directed labeling method that can be used to generate homogeneous immunoconjugate with defined pharmacological properties.
authors.affiliation: Department of Pharmaceutical Product Development, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Forckenbeckstrasse 6, 52074, Aachen. Germany.
authors.forename: Karinna
authors.initials: K
authors.lastname: Chouman
authors.affiliation: Department of Experimental Medicine and Immunotherapy, Institute of Applied Medical Engineering, Helmholtz-Institute for Biomedical Engineering, Pauwelsstrasse 20, 52074, Aachen. Germany.
authors.forename: Mira
authors.initials: M
authors.lastname: Woitok
authors.affiliation: Department of Pharmaceutical Product Development, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Forckenbeckstrasse 6, 52074, Aachen. Germany.
authors.forename: Radoslav
authors.initials: R
authors.lastname: Mladenov
authors.affiliation: Department of Experimental Medicine and Immunotherapy, Institute of Applied Medical Engineering, Helmholtz-Institute for Biomedical Engineering, Pauwelsstrasse 20, 52074, Aachen. Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Kessler
authors.affiliation: Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52056, Aachen. Germany.
authors.forename: Elmar
authors.initials: E
authors.lastname: Weinhold
authors.affiliation: Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52056, Aachen. Germany.
authors.forename: Gisela
authors.initials: G
authors.lastname: Hanz
authors.affiliation: Department of Pharmaceutical Product Development, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Forckenbeckstrasse 6, 52074, Aachen. Germany.
authors.forename: Rainer
authors.initials: R
authors.lastname: Fischer
authors.affiliation: Department of Gynecology and Obstetrics, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen. Germany.
authors.forename: Ivo
authors.initials: I
authors.lastname: Meinhold-Heerlein
authors.affiliation: Department of Gynecology and Obstetrics, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen. Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Bleilevens
authors.affiliation: Department of Pharmaceutical Product Development, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Forckenbeckstrasse 6, 52074, Aachen. Germany.
authors.forename: Gerrit
authors.initials: G
authors.lastname: Gresch
authors.affiliation: Department of Gynecology and Obstetrics, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen. Germany.
authors.forename: Anka Maria
authors.initials: AM
authors.lastname: Haugg
authors.affiliation: Department of Gynecology and Obstetrics, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen. Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Zeppernick
authors.affiliation: Department of Gynecology and Obstetrics, University Medical Center Schleswig-Holstein, Campus Kiel, Arnold-Heller-Strasse 3, 24105 Kiel. Germany.
authors.forename: Dirk
authors.initials: D
authors.lastname: Bauerschlag
authors.affiliation: Department of Gynecology and Obstetrics, University Medical Center Schleswig-Holstein, Campus Kiel, Arnold-Heller-Strasse 3, 24105 Kiel. Germany.
authors.forename: Nicolai
authors.initials: N
authors.lastname: Maass
authors.affiliation: Department of Gynecology and Obstetrics, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074, Aachen. Germany.
authors.forename: Elmar
authors.initials: E
authors.lastname: Stickeler
authors.affiliation: Department of Pharmaceutical Product Development, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Forckenbeckstrasse 6, 52074, Aachen. Germany.
authors.forename: Katharina
authors.initials: K
authors.lastname: Kolberg
authors.affiliation: Department of Gynecology and Obstetrics, University Medical Center Schleswig-Holstein, Campus Kiel, Arnold-Heller-Strasse 3, 24105 Kiel. Germany.
authors.forename: Ahmad Fawzi
authors.initials: AF
authors.lastname: Hussain
mesh_terms: D000906:Antibodies / Q000737:chemistry / Q000627:therapeutic use*; D004305:Dose-Response Relationship, Drug; D066246:ErbB Receptors / Q000032:analysis / Q000096:biosynthesis; D006801:Humans; D007211:Indoles / Q000737:chemistry / Q000627:therapeutic use; D015394:Molecular Structure; D009369:Neoplasms / Q000188:drug therapy*; D017646:Organosilicon Compounds / Q000737:chemistry / Q000627:therapeutic use; D010778:Photochemotherapy; D013329:Structure-Activity Relationship; D000068936:Theranostic Nanomedicine
chemical_list: D000906:Antibodies; C000623382:IRDye700DX N-hydroxysuccinimide ester; D007211:Indoles; D017646:Organosilicon Compounds; C512478:EGFR protein, human; D066246:ErbB Receptors
keywords: EGFR; IRDye700; SNAP-tag technology; Theranostics; antibody drug conjugate; photodynamic therapy; site-directed labeling method