Occurrence of antibodies against herpes simplex virus thymidine kinase in human sera

The occurrence of antibodies in human serum that block herpes simplex virus (HSV) type 1 and 2 deoxythymidine kinase (dTK) has been investigated. The antibodies were detected by means of a sensitive assay technique using [¹²⁵I]iododeoxyuridine as a substrate [Gronowitz and Källander, 1980]. A total of 213 sera was studied. They included pairs of serum from patients with an acute HSV infection, individual sera from persons not suspected of a HSV infection, as well as sera from patients from whom HSV had been isolated. The HSV complement fixing (cf) titer was determined for each serum and subsequently used as a reference. None of the HSV cf negative sera contained HSV dTK blocking antibodies, whereas all cf positive sera did, however, all excepting those that were collected in connection with primary infections. By following the serum titer after a primary infection, we have found that 12 out of 19 persons studied had detectable dTK antibodies after an average time of 179 days. The results indicate a low degree of cross-reactivity between HSV type 1 and 2 dTK blocking antibodies.