Comparison of survival times of mice inoculated with brain tissue from various neurological diseases.

Mice inoculated intracerebrally before the age of 5 days with homogenates of autopsied brain tissue from patients with Creutzfeldt-Jakob (C-J), Alzheimer's, or Pick's diseases showed highly significant decreases in life span when compared with sham-inoculated control mice. With C-J disease there was strong indication of horizontal transmission of the agent to uninoculated mice caged with the inoculated mice. While the results with C-J disease were not unexpected in view of the known infectious etiology of the disease, the results obtained with Alzheimer's and Pick's diseases suggest that previously undetermined infectious or toxic agents may be associated with these two diseases, which currently have unresolved etiologies. Mice inoculated with autopsied brain tissue from patients with multiple sclerosis or subacute sclerosing panencephalitis had life spans similar to those of the control mice.