Recurrent herpes simplex virus type 1 infection precipitated by the impaired production of interleukin-2, alpha-interferon, and cell-mediated cytotoxicity.

In order to understand whether immunosuppression due to the primary host defense defect provokes the reactivation of herpes simplex virus type 1 (HSV-1), 11 healthy persons were evaluated immunologically after recurrence of herpes. A decrease was found in the production of interleukin-2 (IL-2) and alpha-interferon (IFN-alpha) to HSV-1 antigen stimulation in the recrudescent stage (0 to 3 days after onset of the lesion). The cell-mediated cytotoxicity also decreased. To clarify the relationship between the immunosuppression and the occurrence of herpes recurrence, a further longitudinal study was undertaken measuring IL-2, IFN-alpha production, and cell mediated cytotoxicity every other week in 12 persons who suffered frequently from recurrent HSV-1 infection. IL-2 and IFN-alpha production after HSV-1 antigen stimulation and cell-mediated cytotoxicity before recurrence of herpes were lower than those without recurrence. These defective immunologic responses were persistent and became more pronounced during the recrudescent phase. The results suggest that the defect in the immunologic responses to HSV-1 antigen is related to the recurrence of herpes simplex.