Characterization of Canine Adenovirus Type 2 Virus Infection Pattern in Canine and Human Cell Lines

Canine adenovirus type 2 (CAV2) is a nonhuman adenovirus with a known ability to infect human and canine cells. The cell surface receptors involved in CAV2 transduction are still unknown. Identification of these would provide valuable information to develop enhanced gene delivery tools and better understand CAV2 biology. CAV2 is erroneously grouped with Ad5 based on the knowledge that CAV2 may transduce using CAR. Therefore, we have evaluated CAV2 and Ad5 (CAV2GFP, Ad5G/L) infection patterns in various canine and human cell lines to determine their different tropisms. Our research demonstrates that CAV2 can successfully infect cells that Ad5 does not infect, and CAV2 infections do not correlate with CAR expression. CAV2 can infect cells that have a low or minimal expression of CAR. Our data suggest that CAV2 transduction is not dependent on the CAR receptor, and thus, it is crucial to find novel CAV2 receptors.