Immune response to the herpes simplex type 1 regulatory proteins ICP8 and VP16 in infected persons

The specific immune responses directed against the viral single stranded (s s) DNA binding protein ICP8 and the transactivator of immediate early (IE) gene expression VP16 (alpha-trans inducing factor, Vmw65) in HSV type 1 ser opositive humans were examined. The results described in this paper indicat e that neither ICP8 nor VP16 were able to induce a recall response in lymph ocytes of healthy HSV seropositive individuals without recurrent infection, although CD4+ T cells purified from these individuals responded to both vi ral proteins in vitro when monocyte derived dendritic cells were used as an tigen presenting cells. A recall response, however, could be induced to bot h viral proteins in T cells of patients with recurrent HSV infections when blood monocytes were used. Moreover, ICP8- and VP16-specific antibodies cou ld be detected in the serum of patients with recurrent HSV infections where as, in contrast, these antibodies were virtually absent in healthy HSV sero positive individuals without recurrences. These data represent the first sy stematic study of the immunological properties of ICP8 in humans, indicatin g a significant difference in the response to the essential viral regulator s ICP8 and VP16 in HSV-1 seropositive healthy individuals as opposed to pat ients with recurrent HSV-1 infections. J. Med. Virol. 62:29-36, 2000. (C) 2 000 Wiley-Liss, Inc.