Figure 4 demonstrates HCV-2a and HCV-3a rates of active replication [42] in both cell lines, as portrayed by the continuous mRNA expression of the HCV NS3 gene. To our surprise, replication of both viruses was shown to be completely blocked by the presence of increased LSD1 levels; after a short time, there was an HCV NS3 expression boost of at least 17-fold for HCV-2a and 10-fold for HCV-3a, occurring within a time frame dependent on the specific viral strain. Similar results were obtained from cells transfected with pLSD1 30 h prior to infection with HCV-3a (Figure S3). Here, KDM1A is linked to infection.