CD47 and Alzheimer disease: This was also evident from the strong overlap of posterior probability distributions in Fig. 4b, as the presence of AT8 + tau correlated only weakly with CD47, with the probability that AT8 + tau impacts the presence of CD47 in the same synaptosome was calculated as 10.9% in Braak stage 0, 44.7% in stage 3, and 16.7% in stage 6, suggesting that pathological tau-induced loss of CD47 at the single-synapse level may not be a primary mechanism of synaptic loss in AD.