Compared to MOI 1 (Fig. 4D), at MOI 0.1, MDP pretreatment reduced luciferase activity by 80% already during the first cycle (Fig. 4I), and resulted in significant reduction of IE1/2 expression (Fig. 4J), suggesting that similar to the MOI dependency observed when MDP was added after infection, MDP pretreatment was more efficient in virus inhibition at lower MOI. Here, DPEP1 is linked to infection.