Serum antibodies to herpes simplex virus type 1 during active oral herpes infection.

Subjects with oral herpes lesions at the time of serum sampling had higher-efficiency antibody (higher proportion of neutralizing antibody as determined by plaque reduction, compared with total antibody as detected by radioimmunoassay) to herpes simplex virus type 1 (HSV-1) than did subjects with no lesions at the time of serum sampling. These higher-efficiency sera also had higher antibody titers to structural components of herpes simplex virus type 1 than did the low-efficiency sera. Absorption of high- and low-efficiency sera with purified herpes simplex virus type 1 particles removed all neutralizing antibody but not all antibody detected by radioimmunoassay. High-efficiency serum was depleted of more antibody to particulate antigen that was the low-efficiency serum, indicating that the high-efficiency serum contained a higher proportion of antibody to the virus particle.