Differentiation by Immunoferritin of Herpes Simplex Virion Antigens With the Use of Rabbit 7S and 19S Antibodies From Early (7-Day) and Late (7-Week) Immune Sera

Abstract

Baby hamster kidney (BHK-21) cells infected with herpes simplex virus (HSV) were examined before and during viral morphogenesis with ferritin-conjugated early (7-day) and late (7-week) 7S and 19S rabbit anti-HSV antibodies. These 4 antibody fractions, reported elsewhere to differ in their neutralizing properties against the isologous virus and against cross-reacting herpesvirus strains, were found to differ in their reactivity with HSV virion-associated antigens. Before virus appeared, the antigens reactive with early antibodies (7S and 19S) were found in the cytoplasm and the nucleus, whereas most antigens reactive with late antibodies (7S and 19S) were restricted to the nucleus. Evidence obtained suggests that cytoplasmic antigens enter the nucleus through the nuclear pores. At early stages of infection, disrupted nucleoli reacted with early 7S antibodies. Viral cores of low density reacted with early 7S antibodies, whereas viral capsids reacted with both early 19S and late 7S antibodies. Envelopment of capsids occurred at the nuclear and tubular cytoplasmic membranes. Initial stages of envelopment were characterized by the appearance of “early” membrane-associated antigens reactive with early 7S and late 19S antibodies. As the membrane became altered structurally so that it resembled the envelope of the virus, the “early” membrane-associated antigens were no longer detectable, and antigens reactive with early 19S and late 7S antibodies appeared.