Vaccination with HPV16 L2E6E7 fusion protein in GPI-0100 adjuvant elicits protective humoral and cell-mediated immunity

Abstract

A vaccine comprising human papillomavirus type 16 (HPV16) L2, E6 and E7 in a single tandem fusion protein (termed TA-CIN) has the potential advantages of both broad cross-protection against HPV transmission through induction of L2 antibodies able to cross neutralize different HPV types and of therapy by stimulating T cell responses targeting HPV16 early proteins. However, patients vaccinated with TA-CIN alone develop weak HPV neutralizing antibody and E6/E7-specific T cell responses. Here we test TA-CIN formulated along with the adjuvant GPI-0100, a semi-synthetic quillaja saponin analog that was developed to promote both humoral and cellular immune responses. Subcutaneous administration to mice of TA-CIN (20 μg) with 50 μg GPI-0100, three times at biweekly intervals, elicited high titer HPV16 neutralizing serum antibody, robust neutralizing titers for other HPV16-related types, including HPV31 and HPV58, and neutralized to a lesser extent other genital mucosatropic papillomaviruses like HPV18, HPV45, HPV6 and HPV11. Notably, vaccination with TA-CIN in GPI-0100 protected mice from cutaneous HPV16 challenge as effectively as HPV16 L1 VLP without adjuvant. Formulation of TA-CIN with GPI-0100 enhanced the production of E7-specific, interferon γ producing CD8 + T cell precursors by 20-fold. Vaccination with TA-CIN in GPI-0100 also completely prevented tumor growth after challenge with 5 × 10 4 HPV16-transformed TC-1 tumor cells, whereas vaccination with TA-CIN alone delayed tumor growth. Furthermore, three monthly vaccinations with 125 μg of TA-CIN and 1000 μg GPI-0100 were well tolerated by pigtail macaques and induced both HPV16 E6/E7-specific T cell responses and serum antibodies that neutralized all HPV types tested.

Phase II trial of imiquimod and HPV therapeutic vaccination in patients with vulval intraepithelial neoplasia

“…Previous studies have noted a significant correlation between preexisting systemic HPV16-specific T cells and regression of HPV16-positive lesions (Van Poelgeest et al, 2005;Winters et al, 2008). The immune response to the HPV vaccine used in this study might have additional effect if delivered with an adjuvant that can boost both serological and cellular immune responses to its HPV16 antigens (Karanam et al, 2009).…”

“…All the recent studies of immunologically driven treatments of VIN provide momentum for further multicentre randomised trials with consistency in measurement of outcomes and definitions of response. Comparing upfront surgical treatment with imiquimod or other potentially more potent TLR agonists (Fahey et al, 2009) or therapeutic HPV vaccination (Karanam et al, 2009;Kenter et al, 2009), or a combination of TLR agonists with therapeutic HPV vaccination in a crossover study design will be valuable.…”

“…Neutralising antibodies to HPV16 pseudovirions were tested as by the SEAP pseudovirus neutralisation-based assay as previously described (Karanam et al, 2009). …”

Human Papilloma Virus Immunogen Creation on the Base of Chimeric Recombinant Protein L2e7

“…Рекомбинант-ный белок, состоящий из пяти слитых N-концов белков L2 различных штаммов вируса, успешно ренатурировался одноступенчатым диализом против PBS [20], то же самое относится и к Пен-тариксу, молекуле, состоящей из 5 слитых вместе копий Е7 различных штаммов вируса папилло-мы человека [41]. Однако в случае слитых вме-сте белков L2 и E7 (например, рекомбинантного белка L2E6E7 [12], вакцины Ta-CIN, состоящей из слитых L2, E6 и E7 ВПЧ-16 [25], а также реком-бинантного белка, состоящего из L2 и E7 ВПЧ-6 [38]), в работах упоминается очистка белка в вос-станавливающих условиях. Это, очевидно, гово-рит о проблеме корректного образования дис-ульфидных связей при рефолдинге данных бел-ков.…”

EUROGIN 2008 roadmap on cervical cancer prevention

“…Chimeric VLPs or L2 fusion proteins which incorporate polypeptides or peptides of HPV early gene products including E1, E2, E6 and E7 would represent obvious candidates. [65][66][67][68][69] In mice, VLP chimeras have induced both neutralising antibodies and T-cell responses to inserted polypeptides. Unfortunately, therapeutic HPV vaccine efficacy has not been adequately demonstrated to-date and therefore may need to be developed sufficiently and independently before rational combined prophylactic/therapeutic strategies can be undertaken.…”