Morphology and antigen presence determinations of purified mammalian VLPs.

<p>(A), (B) Secreted VLPs and virus were purified by sucrose density gradient ultracentrifugation, negatively stained with 2% uranyl acetate, and observed by TEM at 100,000× magnification; pictures of respective virus strains are shown below the VLPs. (C), (D) Immunogold electron microscopy of purified VLPs. The primary antibodies used are shown below individual panels. Secondary antibody was goat anti-rabbit conjugated to 12 nm gold beads.