Effects of Th17 cells and IL-17 in the progression of cervical carcinogenesis with high-risk human papillomavirus infection

The existence of Th17 cells and IL-17 was recently shown in several types of infectious diseases, but their distribution and functions in cervical lesions with high-risk human papillomavirus (HPV) infection have not been fully elucidated. In this study, the frequency of Th17 cells in peripheral blood samples obtained from 28 cervical squamous cell carcinoma patients, 26 CIN1 patients, 30 CIN2 patients, 29 CIN3 patients, 25 high-risk HPV-infected women with normal cervical cytology, and 30 healthy controls was determined by flow cytometry. Besides, the levels of IL-17 in peripheral blood samples as well as in supernatant of cervical tissue homogenate were assessed by enzyme-linked immunosorbent assay (ELISA) simultaneously. We found that during the disease progression of cervical lesions, the proportion of Th17 cells in the total CD4(+) cells showed a gradually increased tendency compared with the controls (P < 0.05). Moreover, levels of IL-17 in serum and supernatant of cervical tissue homogenate showed the same tendency as the proportion of Th17 cells (P < 0.05). When compared in pairs, the levels of IL-17 in supernatant differed significantly among the study groups and the control group (P < 0.05), but no significant difference was observed in serum (P > 0.05). In conclusions, the results indicate that Th17 cells and IL-17 may play a role of immune enhancement in the infection of high-risk HPV especially in the cervical microenvironment, which contribute to the disease progression of its associated cervical lesions.