The sequential development of abnormal prion protein accumulation in mice with Creutzfeldt-Jakob disease

The distribution and sequential development of prion protein (PrP) accumulation in the central nervous system (CNS) and non-neuronal organs of mice infected with Creutzfeldt-Jakob disease (CJD) were investigated immunohistochemically using a new pretreatment method that greatly enhanced the immunoreactivity of PrP. Prion protein accumulation in the CNS was first detected at 30 days after inoculation and then developed near the inoculation site or periventricular area, and later spread to the whole cerebrum and then to the pons. Its staining took some characteristic forms. Among non-neuronal organs, PrP accumulated in the follicular dendritic cells (FDCs) in spleen, lymph node, Peyer's patch, and thymus. FDCs staining appeared in spleen, lymph node, and Peyer's patch at 21 or 30 days after inoculation, and in thymus at 90 days. Germinal centers developed in the thymus of some CJD-infected mice. No PrP staining was detected in any examined organs of age-matched control mice.