6533b857fe1ef96bd12b43a2

RESEARCH PRODUCT

The effect of arabinofuranosyl-cytosine upon the synthesis of herpesvirus hominis Electron microscopic observations in relation to viral DNA-synthesis

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The paper describes experiments about the degree of dependency of capsid, envelope and antigen synthesis byherpesvirus hominis upon viral DNA synthesis. The DNA synthesis has been blocked by different doses of Ara-C and the remnant DNA-synthesis has been measured by [3H]-thymidine incorporation after CsCl-density gradient centrifugation. Electron microscopic studies were done in parallel after incubation of infected cells with different doses of Ara-C. Finally, antigens were prepared after infection without and with added Ara-C. Increasing amounts of Ara-C inhibited the synthesis of viral DNA and infective particles. 1.5 μg Ara-C reduced the remaining incorporation into DNA to about less than one per cent. In contrast, by electron microscopy considerable amounts of particle synthesis takes place and absorbing capacity for neutralizing antibodies can be observed. Only 15 μg completely prevents the particle synthesis. The same amount completely prevents the synthesis of neutralizing antibody-absorbing capacity. Despite this, the synthesis of membrane bound antigens is not reduced as evidenced by immun-adherence-hemadsorption. It has been concluded that capsid and envelope synthesis is dependent upon viral DNA synthesis. This means, they both may be considered as late proteins. Membrane antigens, by contrast, are to be considered as early antigens. The particle synthesis as shown by ultrathin sections and of absorbing capacity despite complete lack of [3H]-thymidine incorporation into DNA under 1.5 μg per ml of Ara-C is discussed.