Consistent with the high levels of early PrPSc accumulation upon FDC within the GALT (Fig. 3C and D), mice with mature ILF throughout the SI and LI at the time of oral exposure (56-day-old LTβR-Ig-treated mice) succumbed to clinical prion disease at the same time as control mice (322 ± 2 and 321 ± 7 days, respectively; n = 6/group). This evidence concerns the gene LTBR and prion disease.