Immune responses against human papillomavirus (HPV) type 16 virus-like particles in a cohort study of women with cervical intraepithelial neoplasia II. Systemic but not local IgA responses correlate with clearance of HPV-16

To investigate whether there is an association between local or systemic Ig G and IgA responses against human papillomavirus (HPV) type 16 virus-like p articles (VLP) containing L1 and L2 and the possible influence of these res ponses on clearance of HPV-16 and its associated lesions, cervical mucus sa mples from 125 patients and plasma samples from 100 patients, all participa ting in a non-intervention cohort study of women with abnormal cytology, we re analysed. The results show that local IgG and IgA HPV-16 VLP-specific an tibodies do not correlate with virus clearance, However, systemic IgG respo nses were more frequently detected in patients with a persistent infection (11/24) compared with patients with cleared HPV-16 infections (3/28, P= 0.0 06). Furthermore, the ultimate development of high-grade lesions was associ ated with systemic VLP-specific IgG reactivity (P = 0.026). By contrast, sy stemic IgA responses were correlated with virus clearance (7/28 clearance c ompared with 1/24 persistence patients, P = 0.06). This correlation was sta tistically significant when only those clearance patients who tested HPV-16 DNA-positive at more than one visit were included in the analysis (5/11 co mpared with 1/24, P = 0.007), As these systemic IgA responses were not acco mpanied by local IgA responses, the systemic IgA responses in HPV-16 cleara nce patients are suggested to be a by-product of a successful cellular immu ne response induced at the local lymph nodes, mediated by cytokines.