Balance of IgG subclasses toward human papillomavirus type 16 (HPV16) L1-capsids is a possible predictor for the regression of HPV16-positive cervical intraepithelial neoplasia

Human papillomavirus type 16 (HPV16) is known to be a major causative agent of cervical cancer. To test the hypothesis that an enhanced Th1 response f avors the natural course of cervical intraepithelial neoplasia (CIN), we me asured IgG subclasses toward HPV16 L1-capsids because IgG1/IgG2 balance ref lects Th2 and Th1 responses, respectively. We examined IgG2/IgG1 ratios in sera from 67 anti-HPV16 L1-positive women; 18 were cytologically normal wom en, 29 were CIN patients, and 20 were cervical cancer patients. The IgG2 do minance (TgG2/IgG1 ratio >1) was observed in 94, 18, and 5%, respectively ( p < 0.001). The regression rate of CIN lesions was significantly different between patients with and without IgG2 dominance: 83.3% (5/6) versus 16.7% (1/6), respectively (p < 0.05). These findings raise the possibility that I gG2 dominance toward HPV16 L1-capsids, i.e., Th1 dominance, may be a useful marker to predict viral clearance or the regression of HPV16-positive CIN. (C) 1999 Academic Press.