Comparative study of delayed hypersensitivity skin reactions and antibodies to human papilloma virus (HPV)

Abstract

Purified human papilloma virus (HPV) was prepared from plantar warts, inactivated by formalin, adjusted to 10¹⁰ particles per 0·1 ml and used in intradermal tests (IDT) on 120 patients having warts at that time, or having had warts in the past, together with sixty-three controls. Antibodies were evaluated in the sera from most of the patients by the indirect immunofluorescence (IF) test before and after the skin tests. The results showed a specific delayed-hypersensitivity reaction (DHR) to HPV, especially in patients with `regressing' or `past' warts (76%). DHR was most frequent in patients with a wart of 6 months–2 years duration (77·0–68·8%) and persisted much longer than antibodies, which disappeared with the passage of time. The incidence of antibodies was much higher after IDT in patients with a positive reaction, thus suggesting a booster effect.