A novel recombinant protein of ephrinA1–PE38/GM-CSF activate dendritic cells vaccine in rats with glioma

Abstract

Dendritic cells loaded with tumor-associated antigens can effectively stimulate the antitumor immune response of cytotoxic T lymphocytes in the body, which facilitates the development of novel and effective treatments for cancer. In this study, the adenovirus-mediated ephrinA1-PE38/GM-CSF was successfully constructed using the overlap extension method, and verified with sequencing analysis. HEK293 cells were infected with the adenovirus and the cellular expression of ephrinA1-PE38/GM-CSF was measured with an enzyme-linked immunosorbent assay. The recombinant adenovirus was then delivered into the tumor-bearing rats and the results showed that such treatment significantly reduced the volumes of gliomas and improved the survival of the transplanted rats. The results from immunohistochemistry and flow cytometry suggested that this immunomodulatory agent cause activation of dendritic cells. The findings that ephrinA1-PE38/GM-CSF had a high efficacy in the activation of the dendritic cells would facilitate the development of in vivo dendritic-cell vaccines for the treatment of gliomas in rats. Our new method of DC vaccine production induces not only a specific local antitumor immune response but also a systemic immunotherapeutic effect. In addition, this method completely circumvents the risk of contamination related to the in vitro culture of DCs, thus greatly improving the safety and feasibility of clinical application of the DC vaccines in glioma.

Advancements in dendritic cell vaccination: enhancing efficacy and optimizing combinatorial strategies for the treatment of glioblastoma

“…For instance, IL-2 plays a crucial role in T cell activation and proliferation and has been used in combination with DCV to enhance the expansion and activation of tumor-specific T cells (39). Similarly, GM-CSF promotes the maturation and activation of dendritic cells and has been studied as an adjuvant to enhance the immunostimulatory properties of DCV (42). IL-12 promotes the development of T helper 1 (Th1) immune responses and has been used to augment the antitumor immune response in combination with DCV (43).…”

Overview of Current Immunotherapeutic Strategies for Glioma

“…Since 1999, numerous preclinical studies (summarized in Table 1 [37–76]) have analyzed the efficiency of DC vaccines in the treatment of glioma using rodent syngeneic models. The first step in any vaccination protocol is represented by the generation of sufficient number of DCs, typically from bone marrow cells, induced to differentiate with specific cytokines like GM-CSF and/or Flt3L, pulsed with GAAs (tumor lysate or tumor-specific peptide/mRNA epitopes) and injected (most often intradermally or subcutaneously) into animals either prior to or after tumor inoculation (Figure 4).…”

“…These lysates can be generated with methods which induce necrosis or apoptosis: acid elution, freeze-thawing, irradiation, temozolo-mide or thymidine-kinase + GCV treatment [71,173]. Alternatively, tumor RNA and tumor-specific pep-tides/mRNA including ephrin (Eph)-Al, EphA2, IL-13r α 2, survivin, gplOO and TRP-2 have been used to pulse DCs, or DCs have been directly fused to tumor cells [45,46,68,76]. Using multiple epitopes to pulse DCs decreases the risk of developing immune tolerance through immunoediting.…”

“…Numerous preclinical studies have demonstrated that several immunotherapeutic strategies can be successful in animal models of GBM, including: gene therapy [30], passive immunotherapy with antibodies against tumor antigens [31], adoptive T-cell transfer with T cells activated against tumor antigens or engineered to express chimeric antigen receptors (CARs) [32-34], immunomodulatory strategies aimed at inhibiting the immune checkpoints used by tumors to escape from immune surveillance [35,36] as well as active immunotherapy, employing peptide or dendritic cell (DC) vaccines (summarized in Table 1 [37-76]), to elicit immune reactivity against tumors and induce immunological memory capable of preventing recurrence of the disease.…”

‘Smart’ nanoparticles as drug delivery systems for applications in tumor therapy

“…In vivo, DCs with strong phagocytic function patrol different tissues, process exogenous and endogenous antigens, including tumor-associate antigens (TAAs), and then present to T lymphocytes through T-cell receptors (TCRs), after DC maturation [75]. The contacts of a naïve T cell with DC induce T-cell proliferation and differentiation into both memory T cells and effector T cells, which display cell-killing action, resulting in controlling and eliminating cells that exhibit any type of antigen, such as tumor cells or infected cells [76].…”