Replication characteristics and core size of intranuclear herpes simplex virus (HSV-1) in genital skin lesions: Electronmicroscopy studies of a biopsy from a female patient

Abstract

Summary. Herpes simplex virus (HSV) type 1 genital infection, leading to ulcerating lesions in a female patient, was studied by electronmicroscopy. Infection had probably been recent, through oro-genital contact with a cold sore on the husband's lip. Cellculture typing and serological tests indicated that the patient currently had an HSV-1 secondary infection. Aspects studied in a skin biopsy from an ulcerating labium majus were epidermal cell types infected, stages in virus genesis, virus core diameter in intranuclear capsids and extracellular appearance of virus. Different stages in virus genesis, in virus envelope formation and in nuclear and cytoplasmic degeneration were observed in the few remaining, rounded and swollen, epidermal (?) spinosum cells. Their nuclei, some with marginated chromatin, harboured besides dense-cored or empty capsids, electron-dense blobs possibly representing clones of immature virus and falling apart into aggregates of small granules. In other nuclei, large clusters of dense-cored capsids, some distinctly hexagonal in shape, had accumulated in wide gaps in the nuclear membrane whereas remaining nuclear membrane portions were quadruple and often engaged in viral envelope formation. Partially enveloped capsids and naked dense-cored capsids were seen extracellularly indicating their survival outside cells. An occasional virion was present in dermal blood vessel lumina. Measurements of the electron-dense core (nucleoid) of intranuclear capsids in electronmicrographs showed that the HSV-1 core diameter differs very significantly from the core of intranuclear HSV-2 capsids, thus allowing a clear distinction by electronmicroscopy between the two HSV subtypes in plastic-embedded biopsies.

HSV‐2 replication sites, monocyte and lymphocytic cell infection and virion phagocytosis by neutrophils, in vesicular lesions on penile skin

“…Measurements of diameters of eore (nucleoid) and whole capsid of intranuclear HSV-2 were performed on capsids photographed at the highest feasible electron microscope magnification. Data were eompared with previous measurements of diameters of core and whole capsids of intranuclear HSV-1 (11,18). For calculations of exact magnifications of electron micrographs, a referenee grid was photographed (Fulham 1002x, shadow cast crossed lines carbon grating replica; 2160 lines per mm).…”