Abstract
It was confirmed that the titration of slow-reacting complement-requiring neutralizing (s-CRN) antibody was higher in sensitivity than that of complement-requiring neutralizing (CRN) antibody. Then, type-specificity of the s-CRN antibody response in rabbits immunized with herpes simplex virus type 1 (HSV-1) or type 2 (HSV-2) was investigated. A type-specific s-CRN antibody response was found in rabbits immunized with HSV-1, whereas a similar response was not observed in rabbits immunized with HSV-2. In the case of rabbits which received a booster immunization with HSV-2 after primary immunization with HSV-1 or HSV-2, no clear type-specific antibody response could be observed. Also, an appreciable level of type-specific antibody to HSV-2 was not found in the IgM fraction of sera of the rabbits first immunized with HSV-1 and subsequently with HSV-2. The s-CRN antibody activity to HSV-2 after absorption with HSV-1 was found in the sera of the rabbits immunized with HSV-2. In the case of sera of the rabbits immunized with HSV-1, however, the cross-reacting s-CRN antibody activity to HSV-2 was not left after absorption. Moreover, after the absorption, the s-CRN antibody activity to HSV-2 was absent or low in level in sera of the rabbits which received booster immunization with HSV-2 after immunized with HSV-1, but in the case of sera of the rabbits immunized with HSV-2 in primary and booster immunizations the s-CRN activity to HSV-2 was not absorbed.
In conclusion, serological diagnosis of HSV-2 infection based on detection of neutralizing antibody may be possible in the primary HSV-2 infection, whereby the detection of s-CRN antibody must be of a practical use, but, in patients superinfected by HSV-2 after previous HSV-1 infection, serological procedures may have a limited use and virus isolation may be the diagnotic means of choice.
