Figure 4.
Representative electron micrographs from TEM of Spurr resin-sectioned (100 nm sections) THP-1 cells co-cultured with simulated vaccine formulations. Cells were co-cultured for 24 h in R10 medium with 4 μM Aβ42 in the presence of 50 μg/mL Alhydrogel® (Brenntag Biosector, Denmark) (a and d), Imject™ Alum (Pierce, Thermo Scientific) (b and e) or Adju-Phos® (Brenntag, Denmark) (c and f). ThT and lumogallion at 10 and 50 μM respectively, were added at 21 h, as with fluorescence analyses of THP-1 ABA co-cultures. Cell resin-sections were stained for 20 min with 2% w/v ethanolic uranyl acetate, rinsed with 30% v/v ethanol followed by ultrapure water. Grids containing sections were allowed 24 h drying time prior to analysis via TEM. Inserts show close-ups of intracellular negatively stained amyloid (red arrows) co-deposited with ABA (black arrows) within the respective cell images. Magnification & scale bars: (a–c) X 30 K, 1 μm, (d–f) X 100 K, 0.2 μm, respectively.