We examined whether infection with Ad/IFN-λ1 or Ad/IFN-λ2 upregulated expression levels of the MHC class I molecules, and flow cytometrical analyses showed that the transduction increased the class I expression in oesophageal carcinoma and Het-1A cells, although the enhanced levels were variable among the cells (Figure 2B). Here, IFNL2 is linked to infection.