Similarly, the HO-1 expression increased gradually after Ad-Cre infection of IkkβF/F cells, and by 180 days, it reached the levels similar to that in Ikkβ−/− cells and twice that in wild type or Ad-IKKβ-infected IkkβF/F/Ad-Cre cells (Fig. 5D). Here, HMOX1 is linked to infection.