Changes in mitochondrial ultrastructure and dynamics in IgG-APS–treated cells and effects of CoQ₁₀ pretreatment. Monocytes were treated with IgG-APS or IgG-NHS in the presence or in the absence of CoQ₁₀ and then fixed with aldehydes, postfixed with osmium tetroxide, dehydrated, and embedded in epoxy resin. Thin sections were cut and stained with uranyl acetate and lead citrate for observation with an electron microscope. Alternatively, after cell treatments extracts were obtained as described under “Western blotting and EMSAs,” the proteins were separated by SDS-PAGE, transferred to nitrocellulose sheets, and stained with antibodies against proteins controlling mitochondrial fission (Drp1 and Fis1) and fusion (Mfn1, Mfn2, and Opa1). (A) Representative pictures of mitochondria from cells treated as indicated. Bar represents 1 μm. (B) Western blot detection of proteins controlling mitochondrial dynamics. Approximately 20 μg protein was loaded in each lane. This figure depicts a representative result from 3 independent determinations.