Utilizing Computational Machine Learning Tools to Understand Immunogenic Breadth in the Context of a CD8 T-Cell Mediated HIV Response

Predictive models are becoming more and more commonplace as tools for candidate antigen discovery to meet the challenges of enabling epitope mapping of cohorts with diverse HLA properties. Here we build on the concept of using two key parameters, diversity metric of the HLA profile of individuals within a population and consideration of sequence diversity in the context of an individual's CD8 T-cell immune repertoire to assess the HIV proteome for defined regions of immunogenicity. Using this approach, analysis of HLA adaptation and functional immunogenicity data enabled the identification of regions within the proteome that offer significant conservation, HLA recognition within a population, low prevalence of HLA adaptation and demonstrated immunogenicity. We believe this unique and novel approach to vaccine design as a supplement to vitro functional assays, offers a bespoke pipeline for expedited and rational CD8 T-cell vaccine design for HIV and potentially other pathogens with the potential for both global and local coverage.Fil: McGowan, Ed. Imperial College London; Reino UnidoFil: Rosenthal, Rachel. Francis Crick Institute; Reino UnidoFil: Fiore Gartland, Andrew. Fred Hutchinson Cancer Research Cente; Estados UnidosFil: Macharia, Gladys. Imperial College London; Reino UnidoFil: Balinda, Sheila. Uganda Virus Research Institute; UgandaFil: Kapaata, Anne. Uganda Virus Research Institute; UgandaFil: Umviligihozo, Gisele. Center for Family Health Research; RuandaFil: Muok, Erick. Center for Family Health Research; RuandaFil: Dalel, Jama. Imperial College London; Reino UnidoFil: Streatfield, Claire L.. Imperial College London; Reino UnidoFil: Coutinho, Helen. Imperial College London; Reino UnidoFil: Dilernia, Dario. University of Emory; Estados UnidosFil: Monaco, Daniela C.. University of Emory; Estados UnidosFil: Morrison, David. South Walsham; Reino UnidoFil: Yue, Ling. University of Emory; Estados UnidosFil: Hunter, Eric. University of Emory; Estados UnidosFil: Nielsen, Morten. Technical University of Denmark; Dinamarca. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gilmour, Jill. Imperial College London; Reino UnidoFil: Hare, Jonathan. International Aids Vaccine Initiative; Estados Unido

Evaluation of Dried Blood Spots and Oral Fluids as Alternatives to Serum for Human Papillomavirus Antibody Surveillance

Human papillomavirus (HPV) is the causative agent of cervical and other anogenital cancers. HPV vaccination, primarily targeted at young girls before the age of sexual debut, is starting to demonstrate population-level declines in HPV infection and early disease associated with vaccine-incorporated genotypes. Monitoring young women for vaccine-specific antibody is important for vaccine surveillance and may be useful as an adjunct test within a cervical screening context. We evaluated serum, dried blood spots, and oral fluid as potential samples for such applications and report robust measures of diagnostic accuracy. This is the first time a direct comparison of alternative sample types has been made between vaccinated and unvaccinated women for the detection and quantitation of HPV antibodies.Human papillomavirus (HPV) vaccination elicits high-titer genotype-specific antibody responses that are associated with a reduced risk of cervical disease caused by vaccine-incorporated genotypes. Our objective was to evaluate dried blood spots (DBSs) and oral mucosal transudate (OMT) as alternative samples to serum to confirm HPV vaccine antibody status. A study was carried out to evaluate the feasibility of detecting HPV16 and HPV18 antibodies in OMT, DBSs, and sera among women who self-reported being unvaccinated or fully vaccinated with the HPV vaccine. Serum had the highest sensitivity (100%) for detection of antibodies against both HPV16 and HPV18 but the lowest specificity, due to the detection of natural infection antibodies in 16% of unvaccinated women. Conversely, DBSs and OMT had lower sensitivity (96% and 82%, respectively) but high specificity (98%). We confirmed that these antibodies were functional (i.e., neutralizing) and that their detection was quantitatively reproducible and well correlated between sample types when normalized to IgG content. DBSs and OMT are appropriate alternative sample types for HPV vaccine surveillance. These alternative sample types warrant consideration for the purposes of cervical screening, diagnosis, and management, but more work will be needed to establish the stringent parameters required for such application