Wang X.D.,Shenzhen University |
Wang X.D.,Shenzhen Engineering Laboratory of Synthetic Biology |
Gao N.-N.,Shenzhen University |
Gao N.-N.,Shenzhen Engineering Laboratory of Synthetic Biology |
And 15 more authors.
World Journal of Gastroenterology | Year: 2015
Aim: To investigate the effects of our tumor vaccines on reversing immune tolerance and generating therapeutic response. Methods: Vaccines were synthesized by solid phase using an Fmoc strategy, where a small molecule toll-like receptor-7 agonist (T7) was conjugated to a monoclonal gastric cancer 7 antigen mono-epitope (T7-MG1) or tri-epitope (T7-MG3). Cytokines were measured in both mouse bone marrow dendritic cells and mouse spleen lymphocytes after exposed to the vaccines. BALB/c mice were intraperitoneally immunized with the vaccines every 2 wk for a total of three times, and then subcutaneously challenged with Ehrlich ascites carcinoma (EAC) cells. Three weeks later, the mice were killed, and the tumors were surgically removed and weighed. Serum samples were collected from the mice, and antibody titers were determined by ELISA using an alkaline phosphate-conjugated detection antibody for total IgG. Antibody-dependent cell-mediated cytotoxicity was detected by the lactate dehydrogenase method using natural killer cells as effectors and antibody-labeled EAC cells as targets. Cytotoxic T lymphocyte activities were also detected by the lactate dehydrogenase method using lymphocytes as effectors and EAC cells as targets. Results: Vaccines were successfully synthesized and validated by analytical high performance liquid chromatography and electrospray mass spectrometry, including T7, T7-MG1, and T7-MG3. Rapid inductions of tumor necrosis factor-α and interleukin-12 in bone marrow dendritic cells and interferon γ and interleukin-12 in lymphocytes occurred in vitro after T7, T7-MG1, and T7-MG3 treatment. Immunization with T7-MG3 reduced the EAC tumor burden in BALB/c mice to 62.64% 5.55% compared with PBS control (P < 0.01). Six or nine weeks after the first immunization, the monoclonal gastric cancer 7 antigen antibody increased significantly in the T7-MG3 group compared with the PBS control (P < 0.01). As for antibody-dependent cell-mediated cytotoxicity, antisera obtained by immunization with T7-MG3 were able to markedly enhance cell lysis compared to PBS control (31.58% 2.94% vs 18.02% 2.26%; P < 0.01). As for cytotoxic T lymphocytes, T7-MG3 exhibited obviously greater cytotoxicity compared with PBS control (40.92% 4.38% vs 16.29% 1.90%; P < 0.01). Conclusion: A successful method is confirmed for the design of gastric cancer vaccines by chemical conjugation of T7 and multi-repeat-epitope of monoclonal gastric cancer 7 antigen. © 2015 Baishideng Publishing Group Inc. All rights reserved.
Diao Y.,Guangdong University of Technology |
Diao Y.,Shenzhen Engineering Laboratory of Synthetic Biology |
Diao Y.,Dalian Medical University |
Wang X.,Guangdong University of Technology |
And 27 more authors.
Oncology Reports | Year: 2016
Immunotherapy is emerging as a powerful and active tumor-specific approach against cancer via triggering the immune system. Toll like receptors (TLRs) are fundamental elements of the immune system, which facilitate our understanding of the innate and adaptive immune pathways. TLR agonists used as single agents can effectively eradicate tumors due to their potent stimulation of innate and adaptive immunity. We examined the effects of a novel adenine type of TLR7 agonists on both innate and adaptive immune activation in vitro and in vivo. We established the local and distant tumor bearing mice derived from murine mammary carcinoma cell line (4T1) to model metastatic disease. Our data demonstrated that SZU101 was able to stimulate innate immune cells to release cytokines at the very high level compared with LPS at the same or lower concentration. Locally intratumoral SZU101 injection can elicit a systemic antitumor effect on murine breast tumor model. SZU101 affected the frequency of intratumoral immune cell infiltration, including the percentage of CD4+ and CD8+ increase, and the ratio of Tregs decrease. Our data reveal that the antitumor effect of SZU101 is associated with multiple mechanisms, inducing tumor specific immune response, activation of innate immune cells and modulation of the tumor microenvironment.