Cytotoxicity of T cells induced by recoverin-based fusion protein against tumor cells

Xia, Zhijia (2024): Cytotoxicity of T cells induced by recoverin-based fusion protein against tumor cells. Dissertation, LMU München: Medizinische Fakultät

Abstract

Background: Cancer remains the leading cause of mortality and a significant barrier to increasing life expectancy. Despite significant advancements in surgical and chemoradiotherapy techniques, their efficacy in prolonging cancer patient survival is limited. Moreover, treatment effectiveness is further compromised by surgical relapse, distant metastasis, and the development of drug resistance. In recent years, the emergence of immunotherapy as a novel treatment strategy has shown promising results in addressing these challenges. Among the various immunotherapeutic approaches, tumor vaccines have gained considerable attention due to their specificity, accessibility, and minimal side effects. Consequently, there is great interest among researchers in identifying tumor vaccines with high immunogenicity. One such potential candidate is Recoverin, an autoantigen primarily found in the retinal tissue, specifically localized within the blood-retina barrier. Notably, abnormal accumulation of Recoverin has been observed in several tumor cell types, triggering a robust immune response that targets the tumor cells. Additionally, high expression levels of Recoverin protein in tumor patients have been associated with favorable prognoses, suggesting its potential as a cancer vaccine. Furthermore, heat shock protein 70 (HSP70) possesses natural adjuvant properties and is believed to enhance the immunogenicity of self-antigens. Methods: In our previous research, we demonstrated that fusion of Recoverin with HLA class I and II epitopes of HSP70 protein stimulates the activation of dendritic cells (DCs) and CD8+ T cells. In this study, we aim to further investigate the proliferative capacity and anti-tumor cytotoxic effects of T cells induced by the Recoverin fusion protein. To assess T cell proliferation, DCs induced by the Recoverin fusion protein will be co-cultured with CFSE-labeled T cells, and flow cytometry will be employed to detect proliferation signals. Additionally, we co-cultured DCs induced by the Recoverin fusion protein with T cells, followed by co-culturing with Y79 cells after a two-week period. The percentage of 7-AAD+ Y79 cells, measured by flow cytometry, will be utilized as an indicator of the anti-tumor efficacy induced by the Recoverin fusion protein. Results: Our results demonstrate that co-culturing DCs induced by the Recoverin fusion protein with T cells leads to a significant CFSE signal, indicating robust T cell proliferation. Furthermore, when these T cells are subsequently co-cultured with Y79 cells, a higher percentage of 7-AAD+ signals originating from Y79 cells is detected, suggesting an enhanced cytotoxic effect. Conclusion: In comparison to the separate administration of Recoverin peptides or HSP70, the Recoverin fusion protein exhibits superior immunogenicity, highlighting its potential as an cancer vaccine.

• Dokumententyp: Dissertationen (Dissertation, LMU München)
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften ; 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• Fakultäten: Medizinische Fakultät
• Sprache der Hochschulschrift: Englisch
• Datum der mündlichen Prüfung: 30. Juli 2024
• 1. Bericht­erstatter:in: Bazhin, Alexandr