Immunization with fibrillar Aβ1–42 in young and aged canines: Antibody generation and characteristics, and effects on CSF and brain Aβ

We describe a study testing fibrillar β-amyloid1–42 (Aβ42) vaccination in dogs. Three young beagles (4.6 years) were immunized twice with Aβ42 and a Th1 adjuvant (TiterMax Gold). Animals generated primarily IgG2 and IgM antibody responses, which were specific for the Aβ11–30 region of Aβ1–42. Next, 3 aged beagles (8.9–13.8 years) were immunized 4 times with Aβ42 and a Th2 adjuvant (Alum). We observed an acute increase in IgG2, a slower increase in IgG1 and Aβ antibodies of broader specificity (Aβ1–15> Aβ11–30> Aβ6–20). A nonsignificant increase in CSF Aβ1–40 and decrease in Aβ1–40/1–42 in cortex was detected. Canines may be a useful system for testing an Aβ vaccine.