PCSK9 and infection: In addition to Hmgcr, the other proteins in the cholesterol biogenesis cascade (Fig. S5A) and the low-density lipoprotein receptor (Ldlr), as well as proprotein convertase subtilisin/kexin type 9 (Pcsk9), which antagonizes Ldlr (Fig. 2A), were found in increased abundance during the expansion phase of infection compared to their levels in mock-infected control mice.