FIG 3.

PrP^CWD is detected in oropharyngeal lymphoid tissues in 96GG deer at 2 months postexposure (2-MPE collection). (A) RT-QuIC of 96GG WTD, 96GS WTD, and negative-control tissues collected at 2 MPE. PrP^CWD amyloid seeding was detected in oropharyngeal lymphoid tissues from at least 1 96GG WTD collected at 2 MPE, including the tonsil and retropharyngeal, mandibular, and parotid lymph nodes (P < 0.01, unpaired t test). Amyloid formation rates from 96GS WTD tissues were not statistically different from those of the negative control. Data from three 96GG deer (1148, 1157, and 1218), one 96GS deer, and one negative-control deer are represented as means and SEM of 12 replicates from 3 separate experiments. (B) Representative TSA-IHC from 96GG WTD collection at 2 MPE. Mild PrP^CWD immunoreactivity was detected in a small number of germinal center lymphoid follicles (<10 follicles/tissue) in tonsil and retropharyngeal lymph nodes. No PrP^CWD immunoreactivity was observed in corresponding negative controls. Images are at ×200 magnification; scale bar, 50 μm.