20th International AIDS Conference - Melbourne, Australia


WEAB0101 - Oral Abstract

Efficacy of HPV vaccination in HIV+ adolescents and young adults for the induction of strong HPV-specific humoral and cell-mediated immune responses

Presented by Andrew Carr (Australia).

V. Rainone1, D. Trabattoni1, F. Penagini2, V. Fabiano2, V. Giacomet2, A. Viganò2, M. Clerici3,4, G.V. Zuccotti2

1University of Milan, Department of Biomedical and Clinical Sciences L. Sacco, Milan, Italy, 2Luigi Sacco Hospital, Department of Pediatrics, Milan, Italy, 3University of Milan, Department of Physiopathology and Transplants, Milan, Italy, 4Don Carlo Gnocchi Foundation, Milan, Italy

Background: Human Papilloma Virus (HPV)-associated ano-genital infections represent the most common sexually transmitted disease in the general population. The incidence of HPV-associated cancers has been increasing in HIV-infected patients. HPV vaccination may be an important approach to reduce the risk of HPV-associated cancers in HIV-infected patients and a combined strategy of screening and HPV vaccination may guarantee a more adequate prevention of HPV-associated lesions. Immunogenicity of HPV vaccines in HIV-infected patients is still not adequately evaluated. We analysed immunogenicity of a quadrivalent HPV vaccine in HIV-infected patients without baseline molecular evidence of vaccine-type HPV infection focusing on both HPV-specific cell-mediated (CMI) and humoral immunity.
Methods: 31 ARV-treated HIV-infected adolescents (age range 28-14 years, mostly with undetectable viremia and effective CD4 recovery) and 25 sex- and age-matched HIV-seronegative healthy controls were enrolled in the study. Quadrivalent HPV-16/18/6/11 VLP vaccine (GardasilĀ®) was administered 3 times (baseline, 2 months and 6 months). Immune activation (CD4/CD25/HLADRII, CD8/CD25/HLADRII), naїve, effector and memory T-cell patterns, cellular immune responses (CD4/IFN-γ/IL-2, CD8/IFN-γ/TNF-α, CD8/Perforin/GranzymeB) and anti-HPV16/18/6/11 IgG titers were evaluated at baseline and after each immunization.
Results: After the third immunization HIV-infected individuals showed: 1) no changes in CD4 counts, percentage of CD4 cells and HIV viral load; 2) a significant increase in naїve CD8 T-cells, activated CD8 T-cells and in central memory CD4 and CD8 T-cells; 3) a significant reduction in terminally differentiated CD8 T-cells; 4) a significant increase in unstimulated and in HPV-specific IL2+/CD4+, IFN-γ+/CD4+, IFN-γ+/CD8+ and TNF-α+/CD8+ T-cells; 5) a significant increase in HPV-specific Perforin- and Granzyme B-secreting CD8 T-cells. High titers of anti-HPV16/18/6/11 IgG raised shortly after the first immunization and increased over time until the last immunization. Notably, results obtained in HIV-infected patients were comparable to those seen in HC.
Conclusions: Quadrivalent HPV-16/18/6/11 VLP vaccine induces strong HPV-specific cell-mediated and humoral immune responses in ARV-treated HIV-infected individuals that are comparable to those observed in HIV-seronegative controls. HPV-specific CMI is likely an important component of the protective effect of this vaccine, beside the generation of a broad antibody response, data herein indicating that this arm of immunity is not impaired in ARV-treated HIV infected individuals.

Back to the Programme-at-a-Glance