Nelfinavir Impairs Glycosylation of Herpes Simplex Virus 1 Envelope Proteins and Blocks Virus Maturation

Figure 4

NFV treatment impairs HSV-1 maturation and egress. Shown are representative transmission election micrographs, performed 20 hours after HSV-1 infection of HF that were either untreated (panels (a) and (c)) or treated with 10 μM NFV (panels (b) and (d)). Low power micrographs are shown in panels (a) and (b); bar = 2 μm. White arrows indicate HSV-1 capsids in the nucleus (N), black arrowheads indicate capsids in the cytoplasm (C), and black arrows indicate extracellular (E) virions. Similar numbers of capsids were observed in the nucleus of untreated and NFV-treated cells (approximately 39 and 44, resp.). However, untreated cells were observed to have fewer capsids in the cytoplasm (~14 versus 79) and substantially more extracellular virus particles (~51 versus 3). Cytoplasmic virus particles are shown in panels (c) and (d); bar = 0.5 μm. Enveloped virus particles (indicated in panel (c) by a black arrow) were commonly observed in untreated cells but rarely in NFV-treated cells (approximately 9 versus 0, resp., in the fields shown). Capsids in the cytoplasm of NFV-treated cells were almost exclusively nonenveloped (indicated by arrowheads; approximately 16 versus 23 in panels (c) and (d), resp.).

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