scholarly journals Low-Dose Adenovirus Vaccine Encoding Chimeric Hepatitis B Virus Surface Antigen-Human Papillomavirus Type 16 E7 Proteins Induces Enhanced E7-Specific Antibody and Cytotoxic T-Cell Responses

2005 ◽  
Vol 79 (20) ◽  
pp. 12807-12817 ◽  
Author(s):  
Andrés Báez-Astúa ◽  
Elsa Herráez-Hernández ◽  
Natalio Garbi ◽  
Hilda A. Pasolli ◽  
Victoria Juárez ◽  
...  

ABSTRACT Induction of effective immune responses may help prevent cancer progression. Tumor-specific antigens, such as those of human papillomaviruses involved in cervical cancer, are targets with limited intrinsic immunogenicity. Here we show that immunization with low doses (106 infectious units/dose) of a recombinant human adenovirus type 5 encoding a fusion of the E7 oncoprotein of human papillomavirus type 16 to the carboxyl terminus of the surface antigen of hepatitis B virus (HBsAg) induces remarkable E7-specific humoral and cellular immune responses. The HBsAg/E7 fusion protein assembled efficiently into virus-like particles, which stimulated antibody responses against both carrier and foreign antigens, and evoked antigen-specific kill of an indicator cell population in vivo. Antibody and T-cell responses were significantly higher than those induced by a control adenovirus vector expressing wild-type E7. Such responses were not affected by preexisting immunity against either HBsAg or adenovirus. These data demonstrate that the presence of E7 on HBsAg particles does not interfere with particle secretion, as it occurs with bigger proteins fused to the C terminus of HBsAg, and results in enhancement of CD8+-mediated T-cell responses to E7. Thus, fusion to HBsAg is a convenient strategy for developing cervical cancer therapeutic vaccines, since it enhances the immunogenicity of E7 while turning it into an innocuous secreted fusion protein.

Vaccines ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 969
Author(s):  
Dorien De Pooter ◽  
Ellen Van Gulck ◽  
Antony Chen ◽  
Claire F. Evans ◽  
Jean-Marc Neefs ◽  
...  

Despite the availability of an effective prophylactic vaccine for more than 30 years, nearly 300 million people worldwide are chronically infected with the hepatitis B virus (HBV), leading to 1 death every 30 s mainly from viral hepatitis-related cirrhosis and liver cancer. Chronic HBV patients exhibit weak, transient, or dysfunctional CD8+ T-cell responses to HBV, which contrasts with high CD8+ T-cell responses seen for resolvers of acute HBV infection. Therefore, a therapeutic DNA vaccine was designed, expressing both HBV core and polymerase proteins, and was sequence optimized to ensure high protein expression and secretion. Although the vaccine, administered intramuscularly via electroporation, had no effect on plasma viral parameters in a mouse model of persistent HBV infection, it did induce robust HBV-specific immune responses in healthy and adeno-associated hepatitis B virus (AAV-HBV) infected mice as well as in healthy non-human primates.


2018 ◽  
Vol 92 (23) ◽  
Author(s):  
Keigo Kawashima ◽  
Masanori Isogawa ◽  
Susumu Hamada-Tsutsumi ◽  
Ian Baudi ◽  
Satoru Saito ◽  
...  

ABSTRACT Robust virus-specific CD8+ T cell responses are required for the clearance of hepatitis B virus (HBV). However, the factors that determine the magnitude of HBV-specific CD8+ T cell responses are poorly understood. To examine the impact of genetic variations of HBV on HBV-specific CD8+ T cell responses, we introduced three HBV clones (Aa_IND [Aa], C_JPN22 [C22], and D_IND60 [D60]) that express various amounts of HBV antigens into the livers of C57BL/6 (B6) (H-2b) mice and B10.D2 (H-2d) mice. In B6 mice, clone C22 barely induced HBV-specific CD8+ T cell responses and persisted the longest, while clone D60 elicited strong HBV-specific CD8+ T cell responses and was rapidly cleared. These differences between HBV clones largely diminished in H-2d mice. Interestingly, the magnitude of HBV-specific CD8+ T cell responses in B6 mice was associated with the HB core antigen expression level during the early phase of HBV transduction. Surprisingly, robust HBV-specific CD8+ T cell responses to clone C22 were induced in interferon-α/β receptor-deficient (IFN-αβR–/–) (H-2b) mice. The induction of HBV-specific CD8+ T cell responses to C22 in IFN-αβR–/– mice reflects enhanced HBV antigen expression because the suppression of antigen expression by HBV-specific small interfering RNA (siRNA) attenuated HBV-specific T cell responses in IFN-αβR–/– mice and prolonged HBV expression. Collectively, these results suggest that HBV genetic variation and type I interferon signaling determine the magnitude of HBV-specific CD8+ T cell responses by regulating the initial antigen expression levels. IMPORTANCE Hepatitis B virus (HBV) causes acute and chronic infection, and approximately 240 million people are chronically infected with HBV worldwide. It is generally believed that virus-specific CD8+ T cell responses are required for the clearance of HBV. However, the relative contributions of genetic variation and innate immune responses to the induction of HBV-specific CD8+ T cell responses are not fully understood. In this study, we discovered that different clearance rates between HBV clones after hydrodynamic transduction were associated with the magnitude of HBV-specific CD8+ T cell responses and initial HB core antigen expression. Surprisingly, type I interferon signaling negatively regulated HBV-specific CD8+ T cell responses by reducing early HBV antigen expression. These results show that the magnitude of the HBV-specific CD8+ T cell response is regulated primarily by the initial antigen expression level.


2003 ◽  
Vol 77 (9) ◽  
pp. 5464-5474 ◽  
Author(s):  
Katja Nilges ◽  
Hanni Höhn ◽  
Henryk Pilch ◽  
Claudia Neukirch ◽  
Kirsten Freitag ◽  
...  

ABSTRACT Human papillomavirus type 16 (HPV16) E6 and E7 oncoproteins are required for cellular transformation and represent candidate targets for HPV-specific and major histocompatibility complex class I-restricted CD8+-T-cell responses in patients with cervical cancer. Recent evidence suggests that cross-reactivity represents the inherent nature of the T-cell repertoire. We identified HLA-A2 binding HPV16 E7 variant peptides from human, bacterial, or viral origin which are able to drive CD8+-T-cell responses directed against wild-type HPV16 E7 amino acid 11 to 19/20 (E711-19/20) epitope YMLDLQPET(T) in vitro. CD8+ T cells reacting to the HLA-A2-presented peptide from HPV16 E711-19(20) recognized also the HLA-A2 binding peptide TMLDIQPED (amino acids 52 to 60) from the human coronavirus OC43 NS2 gene product. Establishment of coronavirus NS2-specific, HLA-A2-restricted CD8+-T-cell clones and ex vivo analysis of HPV16 E7 specific T cells obtained by HLA-A2 tetramer-guided sorting from PBL or tumor-infiltrating lymphocytes obtained from patients with cervical cancer showed that cross-reactivity with HPV16 E711-19(20) and coronavirus NS252-60 represents a common feature of this antiviral immune response defined by cytokine production. Zero of 10 patients with carcinoma in situ neoplasia and 3 of 18 patients with cervical cancer showed ≥0.1% HPV16 E7-reactive T cells in CD8+ peripheral blood lymphocytes. In vivo priming with HPV16 was confirmed in patients with cervical cancer or preinvasive HPV16-positive lesions using HLA-A2 tetramer complexes loaded with the E6-derived epitope KLPQLCTEL. In contrast, we could not detect E6-reactive T cells in healthy individuals. These data imply that the measurement of the HPV16 E711-19(20) CD8+-T-cell response may reflect cross-reactivity with a common pathogen and that variant peptides may be employed to drive an effective cellular immune response against HPV.


2018 ◽  
Vol 69 (3) ◽  
pp. 584-593 ◽  
Author(s):  
Franziska Rinker ◽  
Christine L. Zimmer ◽  
Christoph Höner zu Siederdissen ◽  
Michael P. Manns ◽  
Anke R.M. Kraft ◽  
...  

2010 ◽  
Vol 17 (10) ◽  
pp. 1576-1583 ◽  
Author(s):  
Mariana O. Diniz ◽  
Marcio O. Lasaro ◽  
Hildegund C. Ertl ◽  
Luís C. S. Ferreira

ABSTRACT Recombinant adenovirus or DNA vaccines encoding herpes simplex virus type 1 (HSV-1) glycoprotein D (gD) genetically fused to human papillomavirus type 16 (HPV-16) oncoproteins (E5, E6, and E7) induce antigen-specific CD8+ T-cell responses and confer preventive resistance to transplantable murine tumor cells (TC-1 cells). In the present report, we characterized some previously uncovered aspects concerning the induction of CD8+ T-cell responses and the therapeutic anticancer effects achieved in C57BL/6 mice immunized with pgD-E7E6E5 previously challenged with TC-1 cells. Concerning the characterization of the immune responses elicited in mice vaccinated with pgD-E7E6E5, we determined the effect of the CD4+ T-cell requirement, longevity, and dose-dependent activation on the E7-specific CD8+ T-cell responses. In addition, we determined the priming/boosting properties of pgD-E7E6E5 when used in combination with a recombinant serotype 68 adenovirus (AdC68) vector encoding the same chimeric antigen. Mice challenged with TC-1 cells and then immunized with three doses of pgD-E7E6E5 elicited CD8+ T-cell responses, measured by intracellular gamma interferon (IFN-γ) and CD107a accumulation, to the three HPV-16 oncoproteins and displayed in vivo antigen-specific cytolytic activity, as demonstrated with carboxyfluorescein diacetate succinimidyl ester (CFSE)-labeled target cells pulsed with oligopeptides corresponding to the H-2Db -restricted immunodominant epitopes of the E7, E6, or E5 oncoprotein. Up to 70% of the mice challenged with 5 × 105 TC-1 cells and immunized with pgD-E7E6E5 controlled tumor development even after 3 days of tumor cell challenge. In addition, coadministration of pgD-E7E6E5 with DNA vectors encoding pGM-CSF or interleukin-12 (IL-12) enhanced the therapeutic antitumor effects for all mice challenged with TC-1 cells. In conclusion, the present results expand our previous knowledge on the immune modulation properties of the pgD-E7E6E5 vector and demonstrate, for the first time, the strong antitumor effects of the DNA vaccine, raising promising perspectives regarding the development of immunotherapeutic reagents for the control of HPV-16-associated tumors.


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