Transmission electron microscopy of rotary shadowed PF4-heparin complexes with KKO antibody bound. Galleries showing the appearance of PF4-heparin complexes with KKO antibody bound. IgG molecules have a typical 3-lobed structure, but their appearance can vary widely because they are quite flexible molecules. (A) Examples of PF4-heparin complexes with a single KKO bound. (B) Examples of PF4-heparin complexes with multiple KKO antibodies bound to each. Below each frame is very high contrast image to highlight the shadowed molecules and eliminate the background. Arrows point to the antibodies. Magnification bar = 50 nm. Adobe Photoshop 7.0 (Adobe, San Jose, CA) was used to produce high-contrast images.