Cellular immune responses to human papillomavirus (HPV) type 16 at the cervix of women with HPV-associated squamous intraepithelial neoplasia

Abstract

Cervical cancer is the most common cause of cancer-related death in black South African women. Human papillomavirus (HPV) has been found to be a necessary causative agent of cervical cancer and has been reported to be associated with 84% of cervical intraepithelial neoplasia (CIN). HPV type 16 (HPV-16) is the most prevalent HPV type associated CIN and cervical cancer with ±56% of women with cervical disease being infected with HPV 16. Yet studies have shown that 47-85% of CIN regressed, suggesting that perhaps an effective immune response could result in HPV clearance and lesion regression. Since HPV infection does not disseminate and there is no systemic phase of infection, it is hypothesized that local cervical immune responses are important in lesion regression and clearance of HPV infection. There are, however, very few studies of mucosal immune responses to HPV infection. The aim of this study was to determine the type of mucosal immune response elicited by the CD4 and CD8 T cell subsets to HPV infection at the cervix of women diagnosed with varying grades of CIN and to compare these to systemic responses.