Substitution of blood coagulation factor X-binding to Ad5 by position-specific PEGylation: Preventing vector clearance and preserving infectivity.
The biodistribution of adenovirus type 5 (Ad5) vector particles is heavily influenced by interaction of the particles with plasma proteins, including coagulation factor X (FX), which binds specifically to the major Ad5 capsid protein hexon. FX mediates hepatocyte transduction by intravenously-injected Ad5 vectors and shields vector particles from neutralization by natural antibodies and complement. In mice, mutant Ad5 vectors that are ablated for FX-binding become detargeted from hepatocytes, which is desirable for certain applications, but unfortunately such FX-nonbinding vectors also become sensitive to neutralization by mouse plasma proteins. To improve the properties of Ad5 vectors for systemic delivery, we developed a strategy to replace the natural FX shield by a site-specific chemical polyethylene glycol shield. Coupling of polyethylene glycol to a specific site in hexon hypervariable region 1 yielded vector particles that were protected from neutralization by natural antibodies and complement although they were unable to bind FX. These vector particles evaded macrophages in vitro and showed significantly improved pharmacokinetics and hepatocyte transduction in vivo. Thus, site-specific shielding of Ad5 vectors with polyethylene glycol rendered vectors FX-independent and greatly improved their properties for systemic gene therapy.
Department of Gene Therapy, Ulm University, Ulm, Germany.
L
L
Krutzke
Department of Gene Therapy, Ulm University, Ulm, Germany.
J M
JM
Prill
Department of Gene Therapy, Ulm University, Ulm, Germany.
T
T
Engler
Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, Ulm, Germany.
C Q
CQ
Schmidt
Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, USA.
Z
Z
Xu
Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD, USA.
A P
AP
Byrnes
Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, Ulm, Germany.
T
T
Simmet
Department of Gene Therapy, Ulm University, Ulm, Germany. Electronic address: florian.kreppel@uni-ulm.de.
F
F
Kreppel
D000260:Adenoviruses, Human / Q000235:genetics*; D000818:Animals; D036022:Capsid Proteins / Q000737:chemistry / Q000235:genetics; D002460:Cell Line; D045744:Cell Line, Tumor; D003165:Complement System Proteins / Q000276:immunology; D003545:Cysteine / Q000235:genetics; D005170:Factor X / Q000235:genetics*; D005260:Female; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins / Q000235:genetics; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D015850:Interleukin-6 / Q000097:blood / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D011092:Polyethylene Glycols / Q000737:chemistry; D014161:Transduction, Genetic
D036022:Capsid Proteins; D015850:Interleukin-6; C485184:enhanced green fluorescent protein; C018315:hexon capsid protein, Adenovirus; C577686:interleukin-6, mouse; D049452:Green Fluorescent Proteins; D011092:Polyethylene Glycols; D005170:Factor X; D003165:Complement System Proteins; D003545:Cysteine
Adenovirus; Blood coagulation factor X; Natural antibodies; PEG; Pharmacokinetics