The LALF32-51 peptide as component of HPV therapeutic vaccine circumvents the alum-mediated inhibition of IL-12 and promotes a Th1 response

Abstract Aluminum-containing adjuvants (alum) continue to be the most widely used adjuvants. It is common knowledge that these adjuvants predominantly induce humoral immunity, but some reports also describe their role combined with IL-12 in the induction of a Th1 immune response. In this study we want to investigate if alum could be an adjuvant to be used as a component of a therapeutic vaccine that require the generation of cell-mediated immunity. To demonstrate this concept we selected the human papillomavirus (HPV) 16-transformed mouse TC-1 cells as model and the fusion protein LALF 32-51 -E7 as antigen. Our results suggest that LALF 32-51 -E7 combined with aluminum hydroxide adjuvant promotes a Th1 immune response and consequently an anti-tumor response in the TC-1 tumor model. These results could have important application in future clinical trials in women with low grade squamous intraepithelial neoplasia.