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Antibodies specific for neutralizing epitopes in either Human papillomavirus (HPV) capsid protein L1 or L2 can mediate protection from viral challenge and thus their accurate and sensitive measurement at high throughput is likely informative for monitoring response to prophylactic vaccination. Here we compare measurement of L1 and L2-specific neutralizing antibodies in human sera using the standard Pseudovirion-Based Neutralization Assay (L1-PBNA) with the newer Furin-Cleaved Pseudovirion-Based Neutralization Assay (FC-PBNA), a modification of the L1-PBNA intended to improve sensitivity towards L2-specific neutralizing antibodies without compromising assay of L1-specific responses. For detection of L1-specific neutralizing antibodies in human sera, the FC- PBNA and L1-PBNA assays showed similar sensitivity and a high level of correlation using WHO standard sera (n = 2), and sera from patients vaccinated with Gardasil (n = 30) or an experimental human papillomavirus type 16 (HPV16) L1 VLP vaccine (n = 70). The detection of L1-specific cross-neutralizing antibodies in these sera using pseudovirions of types phylogenetically-related to those targeted by the L1 virus-like particle (VLP) vaccines was also consistent between the two assays. However, for sera from patients (n = 17) vaccinated with an L2-based immunogen (TA-CIN), the FC-PBNA was more sensitive than the L1-PBNA in detecting L2-specific neutralizing antibodies. Further, the neutralizing antibody titers measured with the FC-PBNA correlated with those determined with the L2-PBNA, another modification of the L1-PBNA that spacio-temporally separates primary and secondary receptor engagement, as well as the protective titers measured using passive transfer studies in the murine genital-challenge model. In sum, the FC-PBNA provided sensitive measurement for both L1 VLP and L2-specific neutralizing antibody in human sera. Vaccination with TA-CIN elicits weak cross-protective antibody in a subset of patients, suggesting the need for an adjuvant.

Background: The first vaccine to prevent human papillomavirus (HPV) and cervical cancer has been licensed, and in future, vaccination may be routinely offered to 10-14 year old girls. HPV is a sexually transmitted virus and some parents may refuse consent for vaccination. Under-16s in the UK have a right to confidential sexual health care without parental consent. We investigated parents' views on making available HPV vaccination to adolescent minors at sexual health clinics without parental consent. Methods: This was a semi-qualitative analysis of views of parents of 11-12 year old school children collected as part of a population-based survey of parental attitudes to HPV vaccination in Manchester. Parents were firstly asked if they agreed that a well-informed child should be able to request vaccination at a sexual health clinic without parental consent, and secondly, to provide a reason for this answer. Ethical perspectives on adolescent autonomy provided the framework for descriptive analysis. Results: 307 parents answered the question, and of these, 244 (80%) explained their views. Parents with views consistent with support for adolescent autonomy (n = 99) wanted to encourage responsible behaviour, protect children from ill-informed or bigoted parents, and respected confidentiality and individual rights. In contrast, 97 parents insisted on being involved in decision-making. They emphasised adult responsibility for a child's health and guidance, erosion of parental rights, and respect for cultural and moral values. Other parents (n = 48) wanted clearer legal definitions governing parental rights and responsibilities or hoped for joint decision-making. Parents resistant to adolescent autonomy would be less likely to consent to future HPV vaccination, (67%) than parents supporting this principle (89%; p < 0.001). Conclusion: In the UK, the principle of adolescent autonomy is recognised and logically should include the right to HPV vaccination, but this may concern parents who would otherwise approve vaccination. [ABSTRACT FROM AUTHOR]