OBJECTIVETo investigate the effect and mechanism of B16F10-ESAT-6-gpi/IL-21 tumor cell vaccine on pulmonary metastasis in mouse model of melanoma.

METHODSTwelve 8-week old female C57BL/6 mice were used in this study. The mice were injected with wild-type B16F10 cells through tail vein after immunization with B16F10-ESAT-6-gpi/IL-21 tumor cell vaccine, and the pulmonary metastasis was observed. The CD4(+) and CD8(+) T cells were isolated by magnetic activated cell sorting, and then used for the detection of CFSE/7-AAD cytotoxicity by flow cytometry. Serum from the mice immunized with tumor-cell vaccine was used to detect IFN-γ expression by ELISA. The expression of TGF-β2, ZEB1, E-cadherin, and N-cadherin of tumor tissues was detected by RT-PCR and immunofluorescence, respectively.

RESULTSThe mice vaccinated with B16F10-ESAT-6-gpi/IL-21 had significantly fewer nodules in the lung and lower lung weight [(285.8 ± 19.01) mg vs. (406.3 ± 27.12) mg], with lower levels of TGF-β2, ZEB1 and N-cadherin proteins but higher level of E-cadherin protein within the tumor tissue, as compared with the control mice. Meanwhile, the immunized mice had significantly increased CD8(+) T cell killing activity [(42.62 ± 3.465)% vs. (22.29 ± 1.804)%] and IFN-γ expression level [(55.200 ± 7.173) pg/ml vs. (6.435 ± 1.339) pg/ml] over the control mice.

CONCLUSIONSThe B16F10-ESAT-6-gpi/IL-21 vaccine can inhibit the metastasis of melanoma in the lung in vaccinated melanoma-bearing mice. This inhibitory effect is associated with CD8(+) T cell immune response and a higher level of IFN-γ, which may influence on the mesenchymal-epithelial transition of tumor cells.

Animals ; CD8-Positive T-Lymphocytes ; immunology ; Cadherins ; metabolism ; Cancer Vaccines ; immunology ; Cell Line, Tumor ; Epithelial-Mesenchymal Transition ; Female ; Homeodomain Proteins ; metabolism ; Humans ; Interferon-gamma ; metabolism ; Interleukins ; immunology ; Lung ; pathology ; Lung Neoplasms ; metabolism ; secondary ; Melanoma ; metabolism ; pathology ; Mice ; Mice, Inbred C57BL ; Neoplasm Transplantation ; Organ Size ; Transcription Factors ; metabolism ; Transforming Growth Factor beta2 ; metabolism ; Zinc Finger E-box-Binding Homeobox 1

OBJECTIVETo develop a prophylactic and therapeutic vaccine against human papillomavirus (HPV) type 58-associated cervical carcinoma, and explore its transformation activity and antigenicity.

METHODSThe E6 and E7 three amino acid codons in the HPV 58 virus were modified respectively and fused. The modified and fused gene was named HPV58 mE6E7. The recombinant HPV58 mE6E7 gene was inserted into pIRES-neo vector to generate plasmid pIRES-neo-HPV58 mE6E7. Then NIH/3T3 cell line was transfected with plasmid pIRES-neo-HPV58 mE6E7. The pIRES-neo-HPV58 mE6E7-transfected cells were the experimental group, pIRES-neo-HPV58 E6E7-transfected cells were the positive control group, and pIRES-neo empty vector-transfected cells were the negative control group. The expression of HPV58 mE6E7 protein in the experimental cells was detected by flow cytometry, immunofluorescence and Western blot. The transformation activity of HPV58 mE6E7 was tested by soft agar colony formation assay and subcutaneously tumors in nude mice. Finally, DNA vaccine was constructed with HPV58 mE6E7 fusion antigen and used to immunize C57BL/6 mice with the vaccine plasmids. The specific serum antibodies were detected by EIISA, and the number of splenic specific CD8(+) T cells secreting IFN-γ of the immunized mice was detected by ELISPOT assay.

RESULTSSequencing confirmed the expected mutation and a 100% homogeneity of the HPV58 E6E7 fusion gene. Stable transfected NIH/3T3 cells expressing HPV58 mE6E7 and HPV58 E6E7 gene were 70.3% and 84.1%, respectively. The relative expressions of HPV58 mE6E7 and HPV58 E6E7 fusion protein in 3T3-HPV58 mE6E7 experimental cells and 3T3-HPV58 E6E7 positive control cells were 2.1 ± 1.7 and 3.8 ± 1.4, respectively, and were negative in the negative control group. No colony formation was found in the experimental and 3T3-neo negative control cell groups, and 31 colonies were found in the positive control cell group, among them 10 colonies were consisted of more than 50 cells. No tumor mass was formed within 4 weeks in the nude mice of experimental and negative control groups, but among the 10 mice of positive control group tumor was formed in 6 mice. Using HPV58 mE6E7 fusion gene as target antigen of DNA vaccine, the antibody titer was 25 600, and specific immunity spots were 218.8 ± 34.4, significantly higher than that in the control group.

CONCLUSIONSThe fused and modified HPV58 E6E7 amino acid codons can abolish the transformation activity but preserve its antigenicity. HPV58 mE6E7 is a potential target gene for the development of therapeutic DNA vaccine against HPV58-associated cervical cancer.

Animals ; Cancer Vaccines ; immunology ; Capsid Proteins ; genetics ; immunology ; Cell Transformation, Neoplastic ; Cloning, Molecular ; Codon ; Female ; Immunoglobulin G ; metabolism ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C57BL ; Mice, Nude ; NIH 3T3 Cells ; Oncogene Proteins, Viral ; genetics ; immunology ; Papillomaviridae ; Papillomavirus E7 Proteins ; genetics ; immunology ; Papillomavirus Vaccines ; immunology ; Plasmids ; Point Mutation ; Random Allocation ; Recombinant Fusion Proteins ; genetics ; immunology ; Transfection ; Vaccines, DNA ; immunology

OBJECTIVETo evaluate the therapeutic effect of MHSP65-TCL on melanoma and its effect on the activity of the immunocytes.

METHODSMHSP65-TCL was prepared by mixing MHSP65 with TCL derived from B16 melanoma cell lysate by repeated freezing and thawing. The MHSP65-TCL vaccine was administered in mice bearing B16 melanoma, and the changes in melanoma growth was observed. To investigate the influence of TCL in MHSP65-TCL on the activity of the immunocytes, we co-cultured TCL and mouse spleen cells in vitro, and analyzed CD69 expression on the cells, cell apoptosis, and levels of IL-10 and IFN-γ in the cell culture supernatant.

RESULTSThe MHSP65-TCL vaccine showed an anti-melanoma effect in the tumor-bearing mice. In the in vitro experiment, TCL in MHSP65-TCL strongly stimulated the activation of mouse spleen cells while causing apoptosis in some of the immunocytes and promoting cellular IL-10 secretion, but not IFN-γ.

CONCLUSIONSMHSP65-TCL derived from B16 melanoma cells has an anti-melanoma effect mediated by the activation of immunocytes. TCL in MHSP65-TCL also has immunosuppressive effect on immunocytes possibly due to the presence of suppressive components in TCL, and identifying and eliminating these components may potentially improve the anti-tumor actovoty of MSHP65-TCL vaccine.

Animals ; Antigens, CD ; metabolism ; Antigens, Differentiation, T-Lymphocyte ; metabolism ; Apoptosis ; Bacterial Proteins ; administration & dosage ; immunology ; Cancer Vaccines ; Cell Extracts ; administration & dosage ; immunology ; Cell Line, Tumor ; Chaperonin 60 ; administration & dosage ; immunology ; Female ; Interferon-gamma ; metabolism ; Interleukin-10 ; metabolism ; Lectins, C-Type ; metabolism ; Melanoma, Experimental ; immunology ; pathology ; Mice ; Mice, Inbred C57BL ; Random Allocation ; Spleen ; cytology ; immunology ; metabolism ; Tumor Burden ; immunology

Human papillomavirus (HPV)-induced cervical cancer is the second most common cancer among women worldwide. Despite the encouraging development of the preventive vaccine for HPV, a vaccine for both prevention and therapy or pre-cancerous lesions remains in high priority. Thus far, most of the HPV therapeutic vaccines are focused on HPV E6 and E7 oncogene. However these vaccines could not completely eradicate the lesions. Recently, HPV E5, which is considered as an oncogene, is getting more and more attention. In this study, we predicted the epitopes of HPV16 E5 by bioinformatics as candidate peptide, then, evaluated the efficacy and chose an effective one to do the further test. To evaluate the effect of vaccine, rTC-1 (TC-1 cells infected by rAAV-HPV16E5) served as cell tumor model and rTC-1 loading mice as an ectopic tumor model. We prepared vaccine by muscle injection. The vaccine effects were determined by evaluating the function of tumor-specific T cells by cell proliferation assay and ELISPOT, calculating the tumor volume in mice and estimating the survival time of mice. Our in vitro and in vivo studies revealed that injection of E5 peptide+CpG resulted in strong cell-mediated immunity (CMI) and protected mice from tumor growth, meanwhile, prolonged the survival time after tumor cell loading. This study provides new insights into HPV16 E5 as a possible target on the therapeutic strategies about cervical cancer.
Adult ; Aged ; Amino Acid Sequence ; Animals ; Cancer Vaccines ; administration & dosage ; immunology ; Cell Line ; Cell Line, Tumor ; Dependovirus ; genetics ; Female ; Gene Expression Regulation, Viral ; immunology ; Genetic Vectors ; genetics ; Human papillomavirus 16 ; genetics ; immunology ; Humans ; Mice ; Mice, Inbred C57BL ; Middle Aged ; Neoplasms, Experimental ; immunology ; prevention & control ; virology ; Oncogene Proteins, Viral ; genetics ; immunology ; Papillomavirus Infections ; immunology ; prevention & control ; virology ; Papillomavirus Vaccines ; administration & dosage ; immunology ; Survival Analysis ; T-Lymphocytes ; immunology ; metabolism ; Tumor Burden ; immunology ; Uterine Cervical Neoplasms ; immunology ; prevention & control ; virology ; Vaccines, Subunit ; administration & dosage ; immunology

PURPOSE: Cancer stem cells have recently been thought to be closely related to tumor development and reoccurrence. It may be a promising way to cure malignant glioma by using glioma stem cell-targeted dendritic cells as a tumor vaccine. In this study, we explored whether pulsing dendritic cells with antigens of glioma stem cells was a potent way to induce specific cytotoxic T lymphocytes and anti-tumor immunity. MATERIALS AND METHODS: Cancer stem cells were cultured from glioma cell line U251. Lysate of glioma stem cells was obtained by the repeated freezing and thawing method. Dendritic cells (DCs) were induced and cultured from the murine bone marrow cells, the biological characteristics were detected by electron microscope and flow cytometry. The DC vaccine was obtained by mixing DCs with lysate of glioma stem cells. The DC vaccine was charactirizated through the mixed lymphocyte responses and cell killing experiment in vitro. Level of interferon-gamma (IFN-gamma) in the supernatant was checked by ELISA. RESULTS: After stimulation of lysate of glioma stem cell, expression of surface molecules of DC was up-regulated, including CD80, CD86, CD11C and MHC-II. DCs pulsed with lysate of glioma stem cells were more effective than the control group in stimulating original glioma cells-specific cytotoxic T lymphocytes responses, killing glioma cells and boosting the secretion of IFN-gamma in vitro. CONCLUSION: The results demonstrated DCs loaded with antigens derived from glioma stem cells can effectively stimulate naive T cells to form specific cytotoxic T cells, kill glioma cells cultured in vitro.
Animals ; Antigens, Neoplasm/immunology ; Apoptosis ; Brain Neoplasms/*therapy ; Cancer Vaccines/*therapeutic use ; Cell Line, Tumor ; Cell Proliferation ; Dendritic Cells/*cytology ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Glioma/*therapy ; Humans ; Interferon-gamma/metabolism ; Male ; Mice ; Mice, Inbred C57BL ; Neoplasm Transplantation ; Neoplastic Stem Cells/*cytology ; T-Lymphocytes, Cytotoxic/immunology

Animals ; Antigens, Neoplasm ; chemistry ; immunology ; Cancer Vaccines ; chemistry ; therapeutic use ; Cell Line, Tumor ; CpG Islands ; Cytotoxicity, Immunologic ; Dendritic Cells ; immunology ; metabolism ; Humans ; In Vitro Techniques ; Lactic Acid ; chemistry ; Leukemia ; immunology ; therapy ; Lymphocytes ; cytology ; immunology ; Nanoparticles ; chemistry ; Peptides ; chemistry ; immunology ; therapeutic use ; Polyglycolic Acid ; chemistry ; Polylactic Acid-Polyglycolic Acid Copolymer ; WT1 Proteins ; chemistry ; immunology

OBJECTIVETo investigate the high expression of HPV16L2N120E7E6 fusion protein by prokaryotic expression system, and evaluate its immunogenicity and antitumor efficacy in vaccinated mice.

METHODSThe HPV16L2N120E7E6 fusion gene, its codons were optimized to increase the expression of the protein, was constructed by overlap extension PCR and inserted into prokaryotic expression vector pET9a. Then the fusion protein was expressed by inducing with IPTG in E. coli strain BL21 (DE3) harboring with plasmid pETL2N120E7E6, and further detected by SDS-PAGE and Western-blot. Finally, the humoral and cellular immune responses were measured by ELISA and ELISPOT, respectively, in vaccinated mice with the purified HPV16L2N120E7E6 fusion protein, and the antitumor efficacy was assessed in mice using the TC-1 tumor challenge model.

RESULTSThe codon-optimized HPV16L2N120E7E6 fusion gene was highly expressed in E. coli strain BL21 (DE3) harboring with plasmid pETL2N120E7E6, and the amount of fusion protein was nearly 48.6% of the total bacterial protein. The purified fusion protein could induce high titer of specific antibody against L2, E7 and E6 in vaccinated mice. When accompanied with the adjuvant CpG, the fusion protein was able to elicit strong and moderate cellular immune responses in vaccinated mice against peptide HPV16E7(49-57) and peptide pools of HPV16E6, respectively. Furthermore, the tumor therapeutic experiment showed that HPV16L2N120E7E6 + CpG could prevent the tumor formation in 80.0% (8/10) vaccinated mice.

CONCLUSIONSThe data of this study suggest that HPV16L2N120E7E6 fusion protein could be a promising candidate vaccine for treatment of chronic HPV16 infection and post-operative adjuvant therapy for cervical cancer.

Adjuvants, Immunologic ; pharmacology ; Animals ; Cancer Vaccines ; immunology ; therapeutic use ; Capsid Proteins ; genetics ; immunology ; metabolism ; Cell Line, Tumor ; Cell Proliferation ; Codon ; Escherichia coli ; immunology ; metabolism ; Female ; Humans ; Immunization ; methods ; Immunotherapy ; methods ; Mice ; Mice, Inbred C57BL ; Neoplasm Transplantation ; Oligodeoxyribonucleotides ; immunology ; Oncogene Proteins, Viral ; genetics ; immunology ; metabolism ; Papillomavirus E7 Proteins ; genetics ; immunology ; metabolism ; Papillomavirus Vaccines ; immunology ; therapeutic use ; Plasmids ; Recombinant Fusion Proteins ; genetics ; immunology ; metabolism ; Repressor Proteins ; genetics ; immunology ; metabolism

OBJECTIVETo explore the anti-tumor mechanism of the combination of cisplatin with DC vaccine in tumor-bearing mice.

METHODSB16 melanoma cells were treated with cisplatin at the final concentration of 20 µg/ml in vitro for 24 h. The expression of HMGB1, Hsp70 and TGF-β were detected by Western blot. B16 tumor-bearing mouse models were generated. The therapeutic effect of the combination of cisplatin (100 µg/mouse i.p., for sequential 3 days) and intratumoral injection of DC cells (3×10(6)/mouse, twice with a 7-day interval) in the tumor-bearing mouse models was evaluated. Expression of MHC II, ICAM-1 and CD86 was analyzed by flow cytometry. The mice were sacrificed at 28 days after tumor cell inoculation. The tumors were removed and weighed, and tissue samples were taken for pathological examination. Tumor infiltrating lymphocytes (TIL) were isolated by discontinuous gradient centrifugation. The distribution of T-reg and CD8(+) T cells in the TIL was analyzed by flow cytometry, and the ratio of CD8(+) T/T-reg was determined. The activity of cytotoxic lymphocytes (CTL) was determined by microcytotoxicity assay.

RESULTSCisplatin enhanced both the B16 cell apoptosis and HMGB1 expression. After loading with cisplatin-treated cell lysate, the expression of MHC II, ICAM-1 and CD86 on DC cells were (47.5 ± 8.8)%, (35.5 ± 8.3)% and (36.2 ± 9.2)%, respectively. At 28 days after tumor cell inoculation, the tumor weight of the control group was (2.1 ± 0.6) g, that of the cisplatin group was (0.3 ± 0.2) g and that of cisplatin + DC vaccine group was (0.5 ± 0.2) g, showing a significant inhibition of tumor growth (P < 0.01). Furthermore, the CD8(+) T/T-reg ratio and CTL activity in TIL were also significantly enhanced in the tumor-bearing mice treated with cisplatin + DC vaccine. When the effector-to-target ratio was 20:1, 10:1 and 5:1, the CTL activity in the cisplatin + DC vaccine treated mice was (25.0 ± 5.0)%, (22.0 ± 6.0)% and (14.0 ± 4.0)%, respectively, significantly higher than (8.2 ± 3.6)%, (6.7 ± 1.8)% and (3.6 ± 1.9)%, respectively, in the control group (all P < 0.01).

CONCLUSIONCisplatin promotes the anti-tumor effect of DC vaccine by down-regulating T-reg cells and enhancing the CTL activity in tumors.

Animals ; Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; B7-2 Antigen ; metabolism ; CD8-Positive T-Lymphocytes ; pathology ; Cancer Vaccines ; pharmacology ; Cell Line, Tumor ; Cisplatin ; pharmacology ; Dendritic Cells ; immunology ; metabolism ; Female ; Genes, MHC Class II ; HMGB1 Protein ; metabolism ; Intercellular Adhesion Molecule-1 ; metabolism ; Melanoma, Experimental ; pathology ; Mice ; Mice, Inbred C57BL ; Neoplasm Transplantation ; T-Lymphocytes, Cytotoxic ; immunology ; T-Lymphocytes, Regulatory ; pathology ; Tumor Burden ; drug effects

OBJECTIVETo explore the cytotoxic responses of spleen T lymphocytes (CTL) in BALB/c mice induced by recombinant HSP110-HER2/neu ICD complex.

METHODSTumor-bearing mouse model was immunized by HSP110-HER2/neu ICD complex. The IFN-γ level secreted by activated spleen T lymphocytes was detected by enzyme linked immunospot assay (ELISPOT). The corresponding CTL activity was measured by granzyme release assay.

RESULTSThe BALB/c mouse model of human mammary tumor highly expressing HER2/neu was established. HSP110-HER2/neu ICD complex immunization led to a significantly higher level of INF-γ than that in HSP110-P(789-797) immunized and HER2/neu ICD immunized mice. HSP110-HER2/neu ICD complex immunized animals also show significant CTL activity. The results of immunohistochemical staining showed that the number of blue spots in the PBS group was 4.57 ± 1.33, HSP110 group 6.83 ± 2.08, HER2/neu ICD group 16.17 ± 2.86, HSP110-P(789-797) group 43.67 ± 4.78, and SP110-HER2/neu ICD group 76.51 ± 8.17. The number of IFN-γ-secreting spleen lymphocytes in the HSP110-HER2/neu ICD group was significantly higher than that in the HSP110-P(789-797) group, and that of HSP110-P(789-797) group was significantly higher than that of HER2/neu ICD group (P < 0.01). The target cell-killing rate of the PBS group was (8.15 ± 1.27)%, HSP110 group (9.51 ± 1.51)%, HER2/neu ICD group (14.03 ± 2.45)%, HSP110-P(789-797) group (25.99 ± 3.04)% and HSP110-HER2/neu ICD group (38.15 ± 3.95)% (all P < 0.01).

CONCLUSIONSHSP110-HER2/neu ICD complex can promote the proliferation and maturation of T lymphocytes into CTLs, and might be used as anti-tumor vaccine to induce potent cytotoxic T lymophocyte immunoresponse against specific tumor cells.

Animals ; Breast Neoplasms ; metabolism ; pathology ; Cancer Vaccines ; immunology ; Cell Line, Tumor ; Cell Proliferation ; Female ; HSP110 Heat-Shock Proteins ; immunology ; Humans ; Interferon-gamma ; metabolism ; Lymphocyte Activation ; Mice ; Mice, Inbred BALB C ; Neoplasm Transplantation ; Random Allocation ; Receptor, ErbB-2 ; immunology ; metabolism ; Recombinant Proteins ; immunology ; Spleen ; cytology ; immunology ; T-Lymphocytes ; cytology ; immunology ; metabolism ; T-Lymphocytes, Cytotoxic ; immunology ; Vaccines, Synthetic ; immunology

Exosomes are small membrane vesicles secreted from various types of cells. Tumor-derived exosomes contain MHC class I molecules and tumor-specific antigens, receiving attention as a potential cancer vaccine. For induction of efficient anti-tumor immunity, CD4+ helper T cells are required, which recognize appropriate MHC class II-peptide complexes. In this study, we have established an MHC class II molecule-expressing B16F1 murine melanoma cell line (B16F1-CIITA) by transduction of the CIITA (Class II transactivator) gene. Exosomes from B16-CII cells (CIITA-Exo) contained a high amount of MHC class II as well as a tumor antigen TRP2. When loaded on dendritic cells (DCs), CIITA-Exo induced the increased expression of MHC class II molecules and CD86 than the exosomes from the parental cells (Exo). In vitro assays using co-culture of immunized splenocytes and exosome-loaded DCs demonstrated that CIITA-Exo enhanced the splenocyte proliferation and IL-2 secretion. Consistently, compared to B16-Exo, CIITA-Exo induced the increased mRNA levels of inflammatory cytokines such as TNF-alpha, chemokine receptor CCR7 and the production of Th1-polarizing cytokine IL-12. A tumor preventive model showed that CIITA-Exo significantly inhibited tumor growth in a dose-dependent manner. Ex vivo assays using immunized mice demonstrated that CIITA-Exo induced a higher amount of Th1-polarized immune responses such as Th1-type IgG2a antibodies and IFN-gamma cytokine as well as TRP2-specific CD8+ T cells. A tumor therapeutic model delayed effects of tumor growth by CIITA-Exo. These findings indicate that CIITA-Exo are more efficient as compared to parental Exo to induce anti-tumor immune responses, suggesting a potential role of MHC class II-containing tumor exosomes as an efficient cancer vaccine.
Animals ; Cancer Vaccines/genetics/immunology ; Cell Line, Tumor ; Cell Proliferation ; Dendritic Cells/immunology ; Exosomes/genetics/*metabolism ; Gene Expression Regulation ; Gene Transfer Techniques ; Immunity, Cellular/immunology ; Immunity, Humoral/immunology ; Immunotherapy ; Lymphocyte Activation/immunology ; Melanoma, Experimental/mortality/pathology/*physiopathology ; Mice ; Mice, Inbred C57BL ; Nuclear Proteins/*genetics/*metabolism ; Survival Analysis ; T-Lymphocytes/immunology/metabolism ; Trans-Activators/*genetics/*metabolism ; Transduction, Genetic