Since less than 2% of CD4/CD8 cells expressing CD25 molecule is observed in the normal endocervix [41] and since CD4/CD25 cells are recognised as regulatory T cells [13], the role of these cells in SIL development should be further evaluated performing longitudinal studies double staining CD4 and CD25. The gene discussed is CD4; the disease is squamous cell intraepithelial neoplasia.