CD8A and cervical squamous intraepithelial neoplasia: Anti-tumor and antiviral effectors include the Th1 subset of CD4+ T cells (expressing cytokines IFN-γ and IL-2), the Th2 subset of CD4+ T cells (expressing cytokine IL-10), CD8+ T cells (clearing virus-infected and diseased cells), and natural killer (NK) cells (8).An effective immune response, including immune clearance and immune balance, can clear most high-risk HPV and lead to the regression of CIN-diseased cells (9).Persistent high-risk HPV infection of the cervix initiates cell transformation into new tumors.