Equivalent amounts of total cell lysates collected from B. burgdorferi cultures (1 – 3 × 107 cells ml−1) were analyzed by SDS-PAGE using pre-cast Novex 4–20% Tris-Glycine polyacrylamide gels (Invitrogen) and transferred to PVDF Immobilon membranes (Millipore) as previously described (Drecktrah et al., 2013 (link)). Protein levels were analyzed by incubating membranes with rabbit antibodies against OspC (1:1000) or mouse antibodies against FlaB (1:50) followed by goat anti-rabbit or goat anti-mouse HRP-linked antibodies (Bio-Rad Laboratories) (1:5000). Blots were developed by chemiluminescence (Amersham ECL Prime, GE Healthcare) and visualized using an LAS-3000 Intelligent Dark Box (Fujifilm Medical Systems USA).