Serum Antibodies against Herpes Simplex Virus Type-1 and Type-2 Early Antigens in Patients with Uterine Cervical Cancer and Healthy Women : Comparison of direct and indirect ELISA titers

Sera from uterine cervical cancer patients (CaCx patients), healthy control and other cancer patients were examined for their IgG and IgM antibody titers against Herpes simplex virus type-1 (HSV-1) and type-2 (HSV-2) early antigens (EA) by using antibody capture direct enzyme-linked immunosorbent assay (direct-ELISA). IgM and IgG antibody titer distribution against HSV-2 EA were compared among CaCx patients, healthy control and other cancer patients. Significant difference in their IgM antibody titer distribution against HSV-2 EA at 2% significance level was observed between CaCx patients and healthy control and also between CaCx patients and other cancer patients. Percentage of the specimens with IgM titers exceeding the upper limit of healthy controls (13ELISA titer) was 6% for CaCx patients but 0% for other cancer patients. In contrast, difference was not observed in IgM titers against HSV-1 EA and in IgG titers against HSV-1 EA and -2 EA between CaCx patients and healthy control. However, percentage of the specimens with HSV-1 EA IgM titers exceeding the upper limit of healthy controls (11 ELISA titer) was 6% for CaCx patients, 1.9% for other cancer patients, IgM and IgG antibody titers against HSV-2 EA measured by direct and indirect ELISA methods were compared among CaCx patients, healthy control and other cancer patients. Correlation between direct and indirect ELISA titers was not observed in those three groups. There were 29 (14.8%) CaCx patients with titer exceeding the upper limit of healthy control measured by either direct-or indirect-IgM ELISA. Five CaCx patients showed titers exceeding the upper limit of healthy control by both direct and indirect ELISA, and 4 of them were found in stage 0 of cervical cancer. However, even among those with high level of IgM ELISA titers, correlation between direct and indirect ELISA titers was not observed. These results suggested that antibodies measured by direct and indirect ELISA were raised against different kinds of early antigens. For the practical use, indirect ELISA method was superior to direct method because of the level of the antibody titers, frequency of detecting positives among in CaCx patients and more easy preparation of the antigens