Antibodies to human papillomavirus type 5 are generated in epidermal repair processes

We reported previously that patients with psoriasis harbored at a very high frequency DNA sequences of the oncogenic human papillomavirus type 5 (HPV5 ) associated with epidermodysplasia verruciformis. Moreover anti-HPV5 antib odies were detected in 25% of the cases. Our aim was to find out whether ke ratinocyte hyperproliferation and/or autoimmunity could be responsible for HPV5 expression in psoriasis. We found that epidermal repair in patients wi th extensive second degree burns (n = 19) is frequently associated with the generation of anti-HPV5 antibodies. In patients with autoimmune bullous di seases (n = 118), a condition in which keratinocyte proliferation is involv ed in repair mechanisms, the prevalence of anti-HPV5 antibodies (15%-25%) w as similar to that reported in psoriasis and significantly higher than that (5%) observed in individuals with no known history of human papillomavirus infection (n = 119). A high detection rate (57.9%) of HPV5 DNA was observe d in patients with bullous diseases. Anti-HPV5 antibodies were found in pat ients with autoimmune connective tissue disorders with cutaneous involvemen t (n = 40) as frequently as in patients with bullous diseases. HPV5 DNA was detected in one of the 10 patients studied. In contrast, the prevalence of anti-HPV5 antibodies in patients with autoimmune neurological disorders (n = 47) and in patients with common warts (n = 28) or invasive carcinomas of the skin (n = 40) was as low as in the general population. It is worth str essing that a similar prevalence of antibodies against HPV1 was found in al l groups studied. Our data strongly suggest that extensive keratinocyte pro liferation is a major factor for the generation of anti-HPV5 antibodies and that autoimmunity may contribute to this phenomenon. It remains to be dete rmined whether HPV5 and other human papillomavirus genotypes associated wit h epidermodysplasia verruciformis contribute to the hyperproliferation of k eratinocytes occurring in epidermal repair and in psoriasis.