Longitudinal study of seroprevalence and serostability of 34 human papillomavirus types in European organ transplant recipients.

Organ transplant recipients (OTR) are at increased risk of cutaneous squamous cell carcinoma, which may be related to reactivation of human papillomavirus (HPV) infections. Measurement of change in HPV antibodies after transplantation would help to explore this hypothesis. We measured antibodies to 34 HPV types on up to six occasions over 18 months in 441 OTRs from five European countries. At baseline (mean 24 days after transplantation), 80% of all OTRs were seropositive to at least one HPV type. The beta HPV genus had the highest seroprevalence (45%). For most HPV genera baseline seroprevalence peaked between 40 and 59 years old. Most OTRs retained their serostatus over time and antibody levels were stable. Seroprevalence in immunosuppressed OTRs is stable in the 18 months immediately after transplantation. Thus there is no short-term evidence that immunosuppression leads to new or reactivated skin infection with HPV sufficient to induce antibodies.

Quantification of beta-human papillomavirus DNA by real-time PCR.

Quantitative PCR with hybridization probes allows the reliable quantification of viral DNA sequences in clinical samples with a dynamic range and sensitivity that cannot be achieved with other methods. The technical background for the establishment of protocols is described and established protocols are presented to estimate the viral load per cell of frequently occurring betapapillomaviruses (HPV5, -8, -15, -20, -23, -24, -36 and -38) in skin tumors, healthy skin and hair bulbs. This approach accurately adjusts dilution series of reference DNA of different viral types relative to pUC18, which is crucial for comparative analyses and for interlaboratory standardization. The type-specific determination of beta-HPV DNA loads is an important research tool toward discrimination between low-level persistence and activated possibly pathologically relevant infections. The analysis of 24 samples, starting with DNA extraction and followed by HPV typing and quantification of-on average-three of the described HPV types takes about 2 d.

Antibody responses to 26 skin human papillomavirus types in the Netherlands, Italy and Australia.

Solar UV radiation is the main risk factor for cutaneous squamous cell carcinoma (SCC), but infections with skin human papillomavirus (HPV) types have also been linked to the development of SCC. Little is known about the natural history of these infections and whether the seroprevalence of skin HPV types is affected by ambient or individual levels of sun exposure. This study investigated this by analysing sera for antibodies to 26 skin HPV types from five phylogenetic genera obtained from 807 healthy individuals from the Netherlands, Italy and Australia, countries with strong differences in sunlight intensity. Overall HPV seroprevalence was similar across the three countries (50-57 % for beta-HPV types, 40-48 % for gamma-HPV types), and the most frequent beta-HPV and gamma-HPV types were the same in all countries. The highest seroprevalences for 24 of the 26 skin HPV types were observed in Italy (14 types) and Australia (ten types). Seroprevalence among men was generally higher than among women, and the male sex was significantly associated with both beta-HPV [odds ratio (OR) 2.81, 95 % confidence interval (CI) 1.64-4.82] and gamma-HPV (OR 2.42, 95 % CI 1.40-4.18) antibodies in Australia. The only measure of sun sensitivity or UV exposure significantly associated with skin HPV seroprevalence was found for weekend sun exposure in Australia and beta-HPV antibodies. It was concluded that type spectra and HPV seroprevalence are similar in countries with different sunlight intensity, and that levels of UV exposure do not play a strong role in the development of skin HPV antibodies in this study population.

High beta-HPV DNA loads and strong seroreactivity are present in epidermodysplasia verruciformis.

Epidermodysplasia verruciformis (EV) is a rare disease, characterized by cutaneous warts and associated with a strong predisposition to beta-genus human papillomavirus (HPV). Earlier studies reported high copy numbers of HPV-DNA in nearly all skin tumors from EV patients, but neither HPV replication status in non-lesional skin nor anti-HPV seroreactivity in these patients have been reported yet. We therefore performed a comprehensive viral load analysis for the more common beta-HPV types on skin samples and plucked eyebrow hairs from four EV patients treated at our dermatology department. The results clearly demonstrate that they carry a multiplicity (up to eighteen types) of beta-HPV genotypes in both skin sites. Worthy of note, a high intrapatient concordance for specific types between hair bulbs and skin biopsies was observed and the same beta-PV profile was maintained over time. Viral load analysis revealed a load range between less than one HPV-DNA copy per 100 cells to more than 400 HPV-DNA copies per cell in both eyebrow hairs and skin proliferative lesions. Evaluation of seroreactivity to beta-HPV types in the four EV patients revealed that antibodies against the 16 beta-HPV were significantly more prevalent and showed higher titers than in the controls.