DKK3 and triple-A syndrome: To further confirm the role of DKK3 in the development of AAA, Dkk3−/−Apoe−/− mice were injected with adeno-associated virus (AAV)-DKK3 (pHBAAV2/9-CMV-m-DKK3-3xflag-T2A-mcherry) for 1.5 × 1012 vector genomes (vg)/ml in 100-μl total volume.