FIGURE 3.

Repression regulation of ospA in mice is not complete until > 72 h after syringe-inoculation and continues throughout the mammalian phase. (A) Representative composite two-photon microscopy images of ear tissues from Myd88^–/– mice 24 and 72 h after needle-inoculation with either PospA-gfp (BbP1981) or PflaB-gfp (BbP1286). Arrowheads indicate intact GFP+ spirochetes. Three-dimensional z-stack images were rendered using Volocity software from images of sequential x, y planes taken at different levels. Hair follicles and dermal collagen fibers fluoresce yellow-orange and blue, respectively, due to second-harmonic generation. A minimum of 20 fields per tissues were examined. Representative images for day 8 and 13 are shown in Supplementary Figure 4A. (B,C) Representative epifluorescence images of 7 μm cryosections of ear and patella collected from Myd88^–/– mice 36 days post-infection (p.i.) by needle with BbP1981 to detect PospA-gfp and PflgB-tdTomato (B) or BbP1286 to detect PflaB-gfp (C). Scale bar, 20 μm.