Generation of fiber-modified adenovirus vectors containing heterologous peptides in both the HI loop and C terminus of the fiber knob.

Fiber-modified adenovirus (Ad) vectors can be effective in overcoming the limitations of conventional Ad vectors, specifically their inefficient gene transfer into cells lacking the primary receptor, the coxsackievirus and adenovirus receptor (CAR). Several types of fiber-modified Ad vectors have been developed. In this study, we evaluated the functionality of several fiber-modified Ad vectors. We developed a simple method based on in vitro ligation to construct Ad vectors containing heterologous foreign peptides in both the HI loop and C terminus of the fiber knob. A functional comparison of Ad vectors containing RGD and/or K7 (KKKKKKK) peptide in the HI loop or C terminus of the fiber knob was performed in several types of human, mouse, and rat cells, including CAR-positive and -negative cells, and tumor cells in mice in vivo. In the case of the in vitro experiment, Ad vectors containing RGD peptide in the HI loop of the fiber knob showed a higher level of gene transfer than vectors containing RGD peptide at the C terminus of the fiber knob. Ad vectors containing K7 peptide at the C terminus of the fiber knob showed levels of gene transfer similar to those of Ad vectors containing RGD peptide in the HI loop of the fiber knob, depending on the cell type. Ad vectors containing both peptides in the HI loop or C terminus of the fiber knob showed the highest levels of gene transfer and a broader tropism. For gene transfer into tumor cells in vivo, the Ad vectors containing RGD peptide were the most efficient. In the experiment using cultured cells, Ad vectors containing both RGD and K7 peptides were the most efficient with a broader tropism. In contrast, in the experiment in vivo, Ad vectors containing RGD peptide in the HI loop of the fiber knob were more efficient than the vectors containing K7 peptide (including double-modified vectors containing both the RGD and K7 peptides). These comparative analyses could provide a systemic reference for the use of fiber-modified Ad vectors. Our simple method, in which the peptide of interest can be expressed in Ad vectors in either the HI loop or the C terminus of the fiber knob, or both, could be a powerful tool for gene transfer into mammalian cells in studies of gene function as well as in gene therapy.

Koizumi N ，Mizuguchi H ，Utoguchi N ，Watanabe Y ，Hayakawa T ... -  《JOURNAL OF GENE MEDICINE》

Fiber-modified adenovirus vectors containing the TAT peptide derived from HIV-1 in the fiber knob have efficient gene transfer activity.

Kurachi S ，Tashiro K ，Sakurai F ，Sakurai H ，Kawabata K ，Yayama K ，Okamoto H ，Nakagawa S ，Mizuguchi H ... -  《GENE THERAPY》

Characterization of capsid-modified adenovirus vectors containing heterologous peptides in the fiber knob, protein IX, or hexon.

Kurachi S ，Koizumi N ，Sakurai F ，Kawabata K ，Sakurai H ，Nakagawa S ，Hayakawa T ，Mizuguchi H ... -  《GENE THERAPY》

Enhanced transduction efficiency of fiber-substituted adenovirus vectors by the incorporation of RGD peptides in two distinct regions of the adenovirus serotype 35 fiber knob.

Fiber-substituted Ad serotype 5 vectors containing the fiber protein from Ad serotype 35 (Ad5F35) exhibit properties that render them suitable as a platform for targeted Ad vectors. Ad5F35 vectors do not show apparent tropism in certain organs, including the liver, and they elicit less innate immunity than other vectors after intravenous administration. In order to develop a targeted Ad vector, we previously developed fiber-mutant Ad5F35 vectors containing the integrin binding Arg-Gly-Asn (RGD) motif in the FG or HI loop of the Ad35 fiber knob. Mutant Ad5F35 vectors containing the RGD peptide in the FG or HI loop transduced CD46-negative cells more efficiently in an RGD-dependent manner, as compared to the efficiency achieved with unmodified Ad5F35 vectors (Matsui et al., 2009. Gene Therapy 16, 1050-1057). However, the transduction efficiency of the mutant Ad5F35 vectors in CD46-negative cells remained lower than had been expected. Ad5F35 vectors containing the RGD peptide in the HI or FG loop enabled a 6-fold higher transduction efficiency than that achieved with unmodified Ad5F35 vectors in CD46-negative cells, although this cell type abundantly expresses α(v)-integrins. In the present study, we aimed to enhance the transduction efficiency of fiber-mutant Ad5F35 vectors. To this end, we developed an Ad5F35-vector system in which foreign peptides could be incorporated into regions of FG and HI loops of the Ad35 fiber knob by means of in vitro ligation. Using this Ad5F35-vector system, firefly luciferase-expressing mutant Ad5F35 vectors containing the RGD peptides in both loops (Ad5F35-2xRGD-L2) were constructed. In CD46-negative cells, Ad5F35-2xRGD-L2 showed 12-fold and 3-fold greater transduction efficiency than unmodified Ad5F35 vectors and mutant Ad5F35 vectors containing only one copy of the RGD peptide in the FG or the HI loop. In addition, transduction with Ad5F35-2xRGD-L2 in CD46-negative cells was RGD peptide-dependent. These results indicate that fiber-mutant Ad5F35 vectors, by which foreign peptides can be simultaneously incorporated into both the FG and the HI loops of the Ad35 fiber knob, could be a promising gene delivery vehicle for various gene therapies, and could facilitate basic research efforts such as analyses of gene function.

Matsui H ，Sakurai F ，Katayama K ，Kurachi S ，Tashiro K ，Sugio K ，Kawabata K ，Mizuguchi H ... -  《-》

CAR- or alphav integrin-binding ablated adenovirus vectors, but not fiber-modified vectors containing RGD peptide, do not change the systemic gene transfer properties in mice.

Mizuguchi H ，Koizumi N ，Hosono T ，Ishii-Watabe A ，Uchida E ，Utoguchi N ，Watanabe Y ，Hayakawa T ... -  《GENE THERAPY》