Tonsil Crypts with HPV (IMAGE) University of Rochester Medical Center Caption These are tonsil crypts with human papillomavirus (HPV; green) in epithelial and biofilm (red) layers ('V' = biofilm; 'G' = HPV; original magnification ×20). Credit Katherine Rieth. M.D. Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.