Specificity: Reacts with a protein of 57kDa, identified as the L1 protein of human papilloma virus type 16 (HPV-16). The antibody reacts very strongly with formalin-fixed, paraffin-embedded tissues containing HPV-16 or -33; very weak reactions were occasionally observed with biopsy specimens or smears containing HPV-6 or HPV-11. It cross-reacts with HPV37. Immunogen: Human papilloma virus type 16, major capsid protein L1