A panel of 24 monoclonal antibodies (MAbs) was generated against human papillomavirus (HPV) types 16 and 18 L1 virus-like particles (VLPs). The MAbs were screened for reactivity to a variety of VLPs prepared from HPV-6, -11, -16, -18, -31, -33, -35, and -45, cottontail rabbit papillomavirus, bovine papillomavirus type 1, and a set of 35 overlapping 20-amino-acid peptides spanning the entire HPV-16 L1 gene. Type-specific linear and conformational surface epitopes were detected as well as several cross-reactive linear epitopes that showed various levels of cross-reactivity between different genital HPV and animal papillomavirus L1s. Most of the linear epitopes were mapped using synthetic peptides, and the epitopes were identified as being either surface or buried within the VLP as defined by the pattern of reactivity in ELISA using intact and disrupted VLP antigen. These MAbs may be useful reagents to help define neutralizing epitopes of HPV-16 and -18 when infectivity assays become available, and to define the regions of L1 that are exposed on the surface or buried within the assembled capsid.

Established Human Papillomavirus (HPV) types, up to HPV202, belong to 49 species in five genera. International standardization in classification and quality standards for HPV type designation and detection is ensured by the International HPV Reference Center. The center i) receives clones of potentially novel HPV types, re-clones and re-sequences them. If confirmed, an HPV type number is assigned and posted on www.hpvcenter.se. ii) distributes reference clone samples, for academic research, under Material Transfer Agreements agreed with the originator. iii) provides preliminary checking of whether new sequences represent novel types iv) issues international proficiency panels for HPV genotyping. The rate of HPV type discovery is increasing, probably because of metagenomic sequencing. γ-genus today contains 79HPV types and 27 species, surpassing ∝ and β genera with 65 and 51HPV types, respectively. Regular issuing of proficiency panels based on HPV reference clones has resulted in global improvement of HPV genotyping services.

-66, and -68). Detection of at least 50 IU of HPV16 or HPV18 DNA and of 500 genome equivalents (GE) of the other 14 HPV types (in samples with single and multiple HPV types) was considered proficient. Fifty-four laboratories worldwide submitted a total of 84 data sets. More than 21 HPV-genotyping assays were used. Commonly used methods were Linear Array, Lineblot, InnoLiPa, Clinical Array, type-specific real-time PCR, PCR-Luminex and microarray assays. The major oncogenic HPV types (HPV16 and -18) were detected in 89.7% (70/78) and 92.2% (71/77) of the data sets, respectively. HPV types 56, 59, and 68 were the least commonly detected types (in less than 80% of the data sets). Twenty-eight data sets reported multiple false-positive results and were considered nonproficient. In conclusion, we found that international proficiency studies, traceable to international standards, allow standardized quality assurance for different HPV-typing assays and enable the comparison of data generated from different laboratories worldwide.Human papillomavirus (HPV) infection has been established as the major cause of cervical cancer (2). Epidemiological studies have classified genital HPV types into high-and low-risk HPV types, reflecting their association with invasive cancer (19). The most important high-risk types, HPV16 and HPV18, account for about 70% of all invasive cervical cancers worldwide. The next most common HPV types on all continents are HPV31, -33, -35, -45, -52, and -58, found in approximately 20% of cervical cancers (19).An accurate and internationally comparable HPV DNA detection and typing methodology is an essential component in the evaluation of HPV vaccines and in effective implementation and monitoring of HPV vaccination programs. The genotyping assays used today differ in their performance with regard to type-specific detection rates (10). As the methodology for quality assurance and evaluation of assay performance is not standardized, comparisons between different studies that use different assays is particularly difficult (10).The World Health Organization (WHO) establishes international biological standard materials and reference reagents for substances of biological origin used in prophylaxis and in therapy or diagnosis of human diseases (http://www.who.int /biologicals/reference_preparations/en/). At the WHO meeting held in Geneva, Switzerland, from 15 to 17 August 2005, an expert group recommended the establishment of a global HPV laboratory network (HPV LabNet) to contribute to improving the quality of laboratory services for effective surveillance and HPV vaccination impact monitoring. Major activities within the HPV LabNet include the development of international standard reagents and standard operating procedures (SOPs) and the development of internationally comparable quality assurance methods (5, 26).International proficiency panels are already widely used for several microorganisms, including hepatitis A, B, and C viruses; herpes simplex virus (HSV); and human immunodeficiency virus (HIV) (15,...

Objectives To assess whether the increased sensitivity of screening for human papillomavirus (HPV) may represent overdiagnosis and to compare the long term duration of protective effect against cervical intraepithelial neoplasia grade 2 or worse (CIN2+) in HPV based and cytology based screening.Design 13 year follow-up of the Swedescreen randomised controlled trial of primary HPV screening.Setting Organised cervical screening programme in Sweden.Participants 12 527 women aged 32-38 attending organised screening were enrolled and randomised to HPV and cytology double testing (intervention arm, n=6257) or to cytology only, with samples frozen for future HPV testing (control arm, n=6270). Main outcome measuresCumulative incidence of CIN2+ and CIN3+ (Kaplan Meier curves). Longitudinal test characteristics were calculated for cytology only, HPV testing only, and cytology and HPV testing combined, adjusting for censoring. ResultsThe increased detection of CIN2+ in the intervention arm decreased over time. After six years, the cumulative incidence of CIN3+ was similar in both trial arms, and after 11 years the cumulative incidence of CIN2+ became similar in both arms. The longitudinal sensitivity of cytology for CIN2+ in the control arm at three years was similar to the sensitivity of HPV testing in the intervention arm at five years of follow-up: 85.94% (95% confidence interval 76.85% to 91.84%) v 86.40% (79.21% to 91.37%). The sensitivity of HPV screening for CIN3+after five years was 89.34% (80.10% to 94.58%) and for cytology after three years was 92.02% (80.59% to 96.97%). ConclusionsOver long term follow-up, the cumulative incidence of CIN2+ was the same for HPV screening and for cytology, implying that the increased sensitivity of HPV screening for CIN2+ reflects earlier detection rather than overdiagnosis. The low long term risks of CIN3+ among women who tested negative in HPV screening, support screening intervals of five years for such women. Trial registration Clinicaltrials.gov NCT00479375. IntroductionCervical screening using cytology has resulted in a noticeable reduction in cervical cancer. However, there are still about 55 000 annual cases of cervical cancer in the European region. 1Infection with oncogenic types of human papillomavirus (HPV) is a necessary risk factor in cervical carcinogenesis 2 and testing for HPV DNA has a higher sensitivity for detection of cervical intraepithelial neoplasia, the precursor lesion of cervical cancer.3-6 Therefore HPV based cervical screening might possibly enable screening programmes with an increased protective effect against cervical cancer. Because HPV infection precedes the development of cervical intraepithelial neoplasia, 7 it is conceivable that HPV based screening could be performed with longer screening intervals, which in turn could result in more cost effective screening. 8Randomised controlled trials of HPV based screening have found that the initial higher detection of cervical intraepithelial neoplasia grade 3 or worse (CIN3+) is followed by a r...

Non-melanoma skin cancers commonly contain Human Papillomavirus (HPV), but the types found have varied depending on the polymerase chain reaction (PCR) primer systems used. Whole genome amplified DNA (not amplified by any specific PCR primers) from 91 skin lesions [41 squamous cell skin carcinomas (SCCs), 8 keratoacanthomas, 22 actinic keratoses, 3 basal cell carcinomas and 17 SCCs in situ] were sequenced. All samples were sequenced both at 160 Mb and 1.8 Gb sequencing depth per sample. The sequences from 10 different HPVs in 47/91 specimens were found. Sequences represented four established HPV types (HPV types 16, 22, 120, 124), two previously known putative types (present in GenBank) and four previously unknown HPV sequences (new putative types). The most commonly detected virus was cloned, sequenced and designated as HPV197. Type-specific real-time PCR detected HPV197 in 34/91 specimens. For comparison, a pool of the same samples after general primer PCR amplification was also sequenced. This revealed 40 different HPVs, but only two HPV types were detected both with sequencing without prior PCR and with sequencing PCR amplicons, suggesting that sequencing without prior PCR gives a more unbiased representation of the HPVs present. In summary, it was found that HPV can be sequenced from most skin disease specimens and HPV197 appeared to be the most commonly present virus.