Cell surface CD1d, a MHC-Ib molecule, is down-regulated in HPV-related lesions and in HPV-negative cervical cancer cell lines stably transfected with HPV-6 E5 and HPV-16 E5, thus linking decreased CD1d expression in the presence of HPV infection with evasion of NKT cells [41]. This evidence concerns the gene CD1D and cervical carcinoma.