Fig. 3

Modelling infection-induced neurodegeneration by delivery of microbial PAMPs in AD mice. A Serum endotoxin levels were measured in 5xFAD mice from either SPF or naturally bred environments at age 7 months. Among the naturally bred environment group, more mice had high serum endotoxin levels, but the difference between the two groups was not significant. B LPS was administered by three intraperitoneally injections to either wt or 5xFAD mice, grown in an SPF environment. C, D Representative images of the cortex stained for NeuN + neurons. C Wt mice, D 5xFAD mice. E Systemic LPS injection did not affect cortical neuronal density in wt mice (n = 4) as compared to the standard density in 7-month-old mice (represented by dashed line) but caused a significant decrease in cortical neuronal density in 5xFAD mice (n = 5). Error bars-SEM. P values by students unpaired T test: *P < 0.05