GFP adenoviral particles expresses Cre via a CMV promoter in the E1 region of the virus and expresses GFP from an RSV promoter in the E3 region. Ready-made control adenoviruses (Ad) are generally in stock and can ship anytime. These particles are CsCl purified and supplied in 100 uL aliquots at 1X10^12 pts/mL. These preps are RCA free and PFU titered.