Antigenic Variations in Herpes Simplex Virus Isolants from Successive Recurrences of Herpes Labialis

Abstract

Thirteen strains of herpes simplex virus (HSV) were isolated from recurrences of herpes labialis in four persons. Antigenic variations among these strains were defined by comparing the kinetics of their neutralization by rabbit antisera against a range of strains. Successive isolants from the same person frequently varied antigenically, but not in a regular manner. Variations could not be correlated with sequence or temporal proximity of recurrences, or with labial sites of lesions. The data substantiated a previously proposed classification of the majority of HSV strains into four serogroups, and indicated existence of two additional serogroups. Neutralization kinetic analysis of the reactions of eight strains from two of the subjects with five samples of their own sera likewise showed that successive isolants from the same individual are not necessarily identical. Relative rates of neutralization indicated that antibody specific for the HSV isolant associated with a given recurrence of herpes labialis is demonstrable in the subject's serum within 18 to 30 hr after the lesion appears. The respective serologic relationships, however, did not correlate with those established by rabbit antisera, and varied with different serum samples from the same person.