APOE and amyloidosis: Cell culture experiments shed some light on the former, in that the effect of APOE4 seems to be a cell-autonomous effect on microglia as when stimulated in culture, they produce more pro-inflammatory cytokines such as IL-1β (Guo et al., 2004), which suggests the differential extent of pathology (e.g., amyloid plaque deposition) as not being the sole driver of the differential increase in cytokines due to APOE4 vs. APOE3 genotype.