Inhibition of oral shedding of herpes simplex virus by cytosine arabinoside.

A patient with acute lymphocytic leukemia in relapse, who developed severe herpetic gingivostomatitis, was treated with cytosine arabinoside (Ara-C). The titer of herpes simplex virus isolated from the mouth showed a rapid but transient decline following iv administration of Ara-C on two separate occasions. In-vitro studies revealed that the inactivating effect of saliva on herpesvirus was cancelled by antibody to IgA. These observations suggest that the diminution of the amount of herpesvirus isolated from the mouth after treatment was probably the result of inhibition of new viral synthesis by Ara-C coincident with neutralization of preformed virus by secretory IgA. Cytosine arabinoside (Ara-C) inhibited the multiplication of several DNA viruses in mammalian cell cultures [1, 2]. These observations have led to the experimental use of this drug in the treatment of life-threatening viral infections [3-6]. Reports of the efficacy of Ara-C in the treatment of these illnesses, however, have been based mainly on clinical impressions. A patient with acute lymphocytic leukemia in relapse who developed severe herpetic gingivostomatitis provided an opportunity to obtain quantitative data on the effect of Ara-C on synthesis of herpes simplex virus (HSV) in vivo. The inhibition of new viral synthesis by Ara-C provided an opportunity to study the role of secretory IgA in the elimination of HSV.