Targeting of adenovirus vectors to the LRP receptor family with the high-affinity ligand RAP via combined genetic and chemical modification of the pIX capsomere.
Adenovirus (Ad) vector targeting requires presentation of specific ligands on the virion's surface. Geneti-chemical targeting is based on the genetic introduction of cysteine residues bearing reactive thiol groups into solvent-accessible capsomeres of the virion and subsequent chemical coupling of ligands. Here, we exploited this technology to modify the pIX capsomere with high-affinity ligands. Genetic introduction of C-terminal cysteines to pIX allowed for specific coupling of full-length proteins to the virion, while not affecting vector production. Direct comparison of the two high-affinity ligands receptor- associated protein (RAP) and transferrin (Tf) revealed that targeting after coupling of a high-affinity ligand to pIX presumably requires release of the ligand from its receptor after cell entry. In addition, data obtained by live cell imaging of labeled vector particles demonstrated that coupling of very large proteins to pIX can impair intracellular vector particle trafficking. Finally, we demonstrate that the geneti-chemical targeting technology is suitable for in vivo targeting to liver after intravenous injection. Our data provide significant insight into basic requirements for successful targeting of pIX-modified Ad vectors.
Corjon
Stéphanie
S
Division of Gene Therapy, University of Ulm, Ulm, Germany.
Wortmann
Andreas
A
Engler
Tatjana
T
van Rooijen
Nico
N
Kochanek
Stefan
S
Kreppel
Florian
F
D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D001710:Biotin / Q000737:chemistry; D036022:Capsid Proteins / Q000737:chemistry / Q000235:genetics*; D002460:Cell Line; D003545:Cysteine / Q000235:genetics; D005260:Female; D005822:Genetic Vectors; D006801:Humans; D026563:LDL-Receptor Related Protein-Associated Protein / Q000737:chemistry*; D026502:LDL-Receptor Related Proteins / Q000378:metabolism*; D008024:Ligands; D008301:Maleimides / Q000737:chemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D011990:Receptors, Transferrin / Q000378:metabolism; D014168:Transferrin / Q000737:chemistry / Q000378:metabolism; D014771:Virion / Q000235:genetics
D036022:Capsid Proteins; D026563:LDL-Receptor Related Protein-Associated Protein; D026502:LDL-Receptor Related Proteins; D008024:Ligands; D008301:Maleimides; D011990:Receptors, Transferrin; D014168:Transferrin; C018315:hexon capsid protein, Adenovirus; D001710:Biotin; D003545:Cysteine