Global Improvement in Genotyping of Human Papillomavirus DNA: the 2011 HPV LabNet International Proficiency Study

Abstract

Cervical cancer is the third most common cancer among women worldwide, with an estimated 530,000 new cases diagnosed annually. Human papillomavirus (HPV) infection is linked to Ͼ99% of cervical cancers (1). The most important highrisk types (HPV16 and HPV18) account for about 70% of all invasive cervical cancers worldwide (2).The introduction of HPV vaccines has highlighted the need for accurate and internationally comparable HPV DNA detection and genotyping methodologies. This is an essential component in both the development and evaluation of HPV vaccines, as well as in the effective implementation and monitoring of HPV vaccination programs. The genotyping assays used today differ in their analytical performances with regard to type-specific sensitivities and specificities. Several studies have compared different HPV typing assays to assess their performances in screening and epidemiology using clinical samples (3-5). However, evaluations of assay performance in different laboratories need to be performed in a standardized manner, such that different assay performance measures can be evaluated and the results can be compared over time against a known and accepted standard (4). The use of regularly issued global proficiency studies is an essential tool for establishing comparable and reliable laboratory services (6). International proficiency panels for quality assurance of laboratory testing are being widely distributed for a number of infectious agents. Recently, the World Health Organization (WHO) issued new reference genotype panels for both parvovirus B19 and hepatitis B virus (7,8).With the objective of facilitating the development and implementation of HPV vaccines by improving and standardizing the quality of HPV laboratory services, the WHO established a global HPV laboratory network (HPV LabNet) in 2005. The main activities within the HPV LabNet were the harmonization and standardization of the laboratory procedures used for HPV vaccine research and HPV vaccination program impact monitoring by the development of internationally comparable quality assurance methods, international standards, and reference reagents, as well as a laboratory manual for vaccinology (9-12). In 2008, recombinant HPV DNA plasmids were used to establish international standards (ISs) for HPV16 and HPV18 DNA, with an assigned potency in international units (IU) (13). That same year, WHO HPV LabNet conducted the first proficiency study that was open for participation from laboratories worldwide based on HPV DNA plasmids containing the genomes of 14 oncogenic and 2 benign HPV types (12,14). In 2010, the proficiency study was repeated, demonstrating that it is possible to perform continuous global studies based on plasmid DNA with unitage traceable to ISs, and that such studies can provide an overview of the status of HPV detection and typing methodologies worldwide (6). The international HPV LabNet proficiency study described herein was designed for the genotyping needs in HPV vaccinology, and the proficiency criteria are not inten...

VALGENT: A protocol for clinical validation of human papillomavirus assays

“…Successive proficiency studies have demonstrated improved proficiency among participating laboratories over time [33,34].…”

Analytical performance evaluation of Anyplex II HPV28 and Euroarray HPV for genotyping of cervical samples

“…The WHO proficiency panel is designed for evaluating HPV assays used in HPV vaccine research and HPV surveillance (Eklund et al, 2014). Samples contained single or multiple HPV genotypes (6, 11, 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68a and 68b), at concentrations of 5 to 500 International Units (IU) or genome equivalents (GE) per 5 μL of DNA (Marcuccilli et al, 2015).…”

How to best measure the effectiveness of male human papillomavirus vaccine programmes?

“…These very sensitive assays are capable of identifying up to 37 individual genotypes including all vaccine-targeted types, the remaining high-risk genotypes and additional low-risk genotypes. A drawback of full-genotyping assays that use consensus primer sets such as PGMY and GP5+/6+ is the tendency for HPV 16 and several other types to outcompete the amplification of a subset of genotypes that are less efficiently amplified by PCR, which theoretically has the potential to artificially alter genotype prevalence estimates between pre-vaccinated and post-vaccinated populations [56][57][58]. This can be overcome by using assays that rely on type-specific primer sets [58]; currently these assays generally identify a smaller range of genotypes and are often more labour-intensive, but recently developed assays may overcome these drawbacks.…”