Abstract
Coxsackievirus and adenovirus receptor (CAR), alphav integrins, and heparan sulfate glycosaminoglycans (HSGs) are the tropism determinants of adenoviral (Ad) vectors in vivo. For the development of a targeted Ad vector, its broad tropism needs to be blocked (or reduced). We have previously developed Ad vectors with ablation of CAR, alphav integrin, and HSG binding by mutation of the FG loop in the fiber knob (deletion of T489, A490, Y491, and T492 of the fiber protein), deletion of the RGD motif of the penton base, and substitution of the fiber shaft domain for that derived from Ad type 35, respectively, and have shown that this triple-mutant Ad vector [Ad/deltaF(FG)deltaP-S35-L2] exhibits significantly lower transduction in mouse liver compared with the conventional Ad vector [Koizumi, N., Mizuguchi, H., Sakurai, F., Yamaguchi, T., Watanabe, Y., and Hayakawa, T. (2003). J. Virol. 77, 13062-13072]. In the present study, we optimized the fiber knob mutation for further reduced in vivo transduction and examined toxicity of the modified Ad vectors. Ad/deltaF(AB)deltaPS35- L2, a triple-mutant Ad vector containing a mutation of the AB loop in the fiber knob (R412S, A415G, E416G, and K417G), mediated approximately 15,000- and 500-fold lower mouse liver transduction by intravenous and intraperitoneal administration, respectively, than the conventional Ad vector, and mediated 10- fold lower mouse liver transduction than did Ad/deltaF(FG)deltaP-S35-L2. Ad/deltaF(AB)deltaP-S35-L2 also exhibited lower transduction of other organs compared with Ad/deltaF(FG)deltaP-S35-L2 and the conventional Ad vector. Levels of both liver serum enzymes (aspartate transferase [AST] and alanine transferase (ALT)] and interleukin (IL)-6 in mouse serum after intravenous administration of Ad/deltaF(AB)deltaP-S35-L2 were similar to those in the nontreatment mouse serum, whereas the conventional Ad vector led to high levels of AST, ALT, and IL-6. We therefore succeeded in further improving the mutant Ad vector, abolishing both viral natural tropism and toxicity. This new Ad vector appears to be a fundamental vector for targeted gene delivery.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.