Research progress on mitochondria regulating anti-tumor immunity / 浙江大学学报·医学版

Tumor cells adaptively reforge their metabolism to meet the demands of energy and biosynthesis. Mitochondria, pivotal organelles in the metabolic reprogramming of tumor cells, contribute to tumorigenesis and cancer progression significantly through various dysfunctions in both tumor and immune cells. Alterations in mitochondrial dynamics and metabolic signaling pathways exert crucial regulatory influence on the activation, proliferation, and differentiation of immune cells. The tumor microenvironment orchestrates the activation and functionality of tumor-infiltrating immune cells by reprogramming mitochondrial metabolism and inducing shifts in mitochondrial dynamics, thereby facilitating the establishment of a tumor immunosuppressive microenvironment. Stress-induced leakage of mitochondrial DNA contributes multifaceted regulatory effects on anti-tumor immune responses and the immunosuppressive microenvironment by activating multiple natural immune signals, including cGAS-STING, TLR9, and NLRP3. Moreover, mitochondrial DNA-mediated immunogenic cell death emerges as a promising avenue for anti-tumor immunotherapy. Additionally, mtROS, a crucial factor in tumorigenesis, drives the formation of tumor immunosuppressive microenvironment by changing the composition of immune cells within the tumor microenvironment. This review focuses on the intrinsic relationship between mitochondrial biology and anti-tumor immune responses from multiple angles. We expect to explore the core role of mitochondria in the dynamic interplay between the tumor and the host, in order to facilitate the development of targeted mitochondrial strategies for anti-tumor immunotherapy.

Tumor cell lysate with low content of HMGB1 enhances immune response of dendritic cells against lung cancer in mice / 南方医科大学学报

OBJECTIVE@#To assess the effect of tumor cell lysate (TCL) with low high-mobility group B1 (HMGB1) content for enhancing immune responses of dendritic cells (DCs) against lung cancer.@*METHODS@#TCLs with low HMGB1 content (LH-TCL) and normal HMGB1 content (NH-TCL) were prepared using Lewis lung cancer (LLC) cells in which HMGB1 was inhibited with 30 nmol/L glycyrrhizic acid (GA) and using LLC cells without GA treatment, respectively. Cultured mouse DCs were exposed to different doses of NH-TCL and LH-TCL, using PBS as the control. Flow cytometry was used to detect the expressions of CD11b, CD11c and CD86 and apoptosis of the stimulated DCs, and IL-12 levels in the cell cultures were detected by ELISA. Mouse spleen cells were co-cultured with the stimulated DCs, and the activation of the spleen cells was assessed by detecting CD69 expression using flow cytometry; TNF-β production in the spleen cells was detected with ELISA. The spleen cells were then co-cultured with LLC cells at the effector: target ratios of 5:1, 10:1 and 20:1 to observe the tumor cell killing. In the animal experiment, C57/BL6 mouse models bearing subcutaneous LLC xenograft received multiple injections with the stimulated DCs, and the tumor growth was observed.@*RESULTS@#The content of HMGB1 in the TCL prepared using GA-treated LLC cells was significantly reduced (P < 0.01). Compared with NH-TCL, LH-TCL showed a stronger ability to reduce apoptosis (P < 0.001) and promote activation and IL- 12 production in the DCs. Compared with those with NH-TCL stimulation, the DCs stimulated with LH-TCL more effectively induced activation of splenic lymphocytes and enhanced their anti-tumor immunity (P < 0.05). In the cell co-cultures, the spleen lymphocytes activated by LH-TCL-stimulated DCs showed significantly enhanced LLC cell killing activity (P < 0.01). In the tumor-bearing mice, injections of LH-TCL-stimulated DCs effectively activated host anti-tumor immunity and inhibited the growth of the tumor xenografts (P < 0.05).@*CONCLUSION@#Stimulation of the DCs with LH-TCL enhances the anti-tumor immune activity of the DCs and improve the efficacy of DCbased immunotherapy for LLC in mice.

Biological Functions of CD24 in Malignant Tumor and its Application as a Novel Anti-tumor Target / 中国生物化学与分子生物学报

CD24 is a highly glycosylated protein that is linked to the plasma membrane via a glycosylphosphatidylinositol anchor. As a universally expressed protein on immune cells, CD24 is also overexpressed in nearly 70% of human cancers including hepatocellular carcinoma, lung cancer and bladder cancer et al. Studies revealed that CD24 is involved in regulating cell proliferation, migration and invasion in cancer cells by interacting with P-selectin, activating Wnt and MAPK signaling pathway or other signaling molecules. Therefore, CD24-targeted siRNA or antibody has a great potential to exert anti-tumor effects by blocking the interaction. There are currently several agents or regiments targeting CD24 for the treatment of patients with various kinds of cancers that are undergoing assessment in the preclinical study at present. Recent studies revealed that CD24 was able to interact with the inhibitory receptor sialic-acid-binding Ig-like lectin 10 (Siglec-10), which located on the surface of macrophages, to compose a novel immune checkpoint. The binding of CD24 to Siglec-10 elicits an inhibitory signaling cascade, limits macrophage phagocytosis, evades immune surveillance, and promotes tumor growth, which suggested that CD24 may be a potential target in anti-tumor immunotherapy. In this review, we introduced the structure and function of CD24 and its role in cancer progression and anti-tumor immunity. Moreover, the progression in developing novel anti-cancer drugs or treatment strategies with the target of CD24 was summarized, which aims to provide a new insight in CD24-targeting therapy.

Macrophage-camouflaged epigenetic nanoinducers enhance chemoimmunotherapy in triple negative breast cancer

Chemoimmunotherapy has been approved as standard treatment for triple-negative breast cancer (TNBC), but the clinical outcomes remain unsatisfied. Abnormal epigenetic regulation is associated with acquired drug resistance and T cell exhaustion, which is a critical factor for the poor response to chemoimmunotherapy in TNBC. Herein, macrophage-camouflaged nanoinducers co-loaded with paclitaxel (PTX) and decitabine (DAC) (P/D-mMSNs) were prepared in combination with PD-1 blockade therapy, hoping to improve the efficacy of chemoimmunotherapy through the demethylation of tumor tissue. Camouflage of macrophage vesicle confers P/D-mMSNs with tumor-homing properties. First, DAC can achieve demethylation of tumor tissue and enhance the sensitivity of tumor cells to PTX. Subsequently, PTX induces immunogenic death of tumor cells, promotes phagocytosis of dead cells by dendritic cells, and recruits cytotoxic T cells to infiltrate tumors. Finally, DAC reverses T cell depletion and facilitates immune checkpoint blockade therapy. P/D-mMSNs may be a promising candidate for future drug delivery design and cancer combination therapy in TNBC.

Salvianolic acid B exerts its anti-tumor immunity by targeting USP2 and reducing the PD-L1 level / 药学学报

With the development of small-molecule immunotherapy drugs, its combination with the programmed cell death ligand 1/programmed cell death protein 1 (PD-L1/PD-1) antibodies would provide a new opportunity for cancer treatment. Therefore, targeting PD-L1/PD-1 axis by small-molecule drug is an attractive approach to enhance antitumor immunity and considered as the next generation of tumor immunotherapy. In the present study, we investigated the anti-tumor role of salvianolic acid B (SAB) by regulating the PD-L1 level in tumors. Changes of total PD-L1 and membrane PD-L1 levels were determined by Western blot, flow cytometry and PD-1/PD-L1 interaction assays. The expression of mRNA level of PD-L1 was detected by real-time PCR. The cytotoxicity of activated peripheral blood mononuclear cell (PBMC) cells toward co-cultured tumor cells was measured by cell impedance assay and crystal violet experiment. Surface plasma resonance technique was used to analyze the direct interaction between SAB and ubiquitin carboxyl-terminal hydrolase 2 (USP2). The antitumor effect of SAB in vivo was examined by C57BL/6 mice bearing MC38 xenograft tumor (all animal experiments were conducted in accordance with the Animal Ethics Committee of the Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences). Western blot and flow cytometry assay showed that SAB can significantly downregulate the abundance of PD-L1 in RKO and PC3 cells in dose- and time-dependent manner. PD-1/PD-L1 binding assay revealed that SAB reduces the binding of tumor cells to recombinant PD-1 protein. Mechanism studies revealed that SAB can bind directly to USP2 protein and inhibit its activity, thus promote the ubiquitin-proteasome pathway degradation of PD-L1 proteins. In addition, Cell impedance and crystal violet staining indicated that SAB enhances the killing activity of co-cultured PBMC cells toward tumor cells. MC38 tumor transplanted mouse experiments revealed that SAB treatment displayed significant suppression in the growth of MC38 tumor xenografts in C57BL/6 mice with an inhibition rate of 63.2% at 20 mg·kg-1. Our results demonstrate that SAB exerts its anti-tumor activity by direct binding and inhibiting the activity of USP2 and reducing the PD-L1 level. Our study provides an important material basis and scientific basis for the potential application of SAB in tumor immunotherapy drug targeting USP2-PD-L1 axis.

Pancreatic melatonin enhances anti-tumor immunity in pancreatic adenocarcinoma through regulating tumor-associated neutrophils infiltration and NETosis

Tumor microenvironment contributes to poor prognosis of pancreatic adenocarcinoma (PAAD) patients. Proper regulation could improve survival. Melatonin is an endogenous hormone that delivers multiple bioactivities. Here we showed that pancreatic melatonin level is associated with patients' survival. In PAAD mice models, melatonin supplementation suppressed tumor growth, while blockade of melatonin pathway exacerbated tumor progression. This anti-tumor effect was independent of cytotoxicity but associated with tumor-associated neutrophils (TANs), and TANs depletion reversed effects of melatonin. Melatonin induced TANs infiltration and activation, therefore induced cell apoptosis of PAAD cells. Cytokine arrays revealed that melatonin had minimal impact on neutrophils but induced secretion of Cxcl2 from tumor cells. Knockdown of Cxcl2 in tumor cells abolished neutrophil migration and activation. Melatonin-induced neutrophils presented an N1-like anti-tumor phenotype, with increased neutrophil extracellular traps (NETs) causing tumor cell apoptosis through cell-to-cell contact. Proteomics analysis revealed that this reactive oxygen species (ROS)-mediated inhibition was fueled by fatty acid oxidation (FAO) in neutrophils, while FAO inhibitor abolished the anti-tumor effect. Analysis of PAAD patient specimens revealed that CXCL2 expression was associated with neutrophil infiltration. CXCL2, or TANs, combined with NET marker, can better predict patients' prognosis. Collectively, we discovered an anti-tumor mechanism of melatonin through recruiting N1-neutrophils and beneficial NET formation.

Preclinical study of LMP1-RNAi-based anti-tumor therapy in EBV-positive nasopharyngeal carcinoma

RNA interference (RNAi) treatment has been proven to be an important therapeutic approach in cancer based on downregulation of target-oncogenes, but its clinical efficacy still needs further investigation. LMP1 is usually presented by Epstein-Barr virus (EBV)-positive tumor cells like EBV-associated nasopharyngeal carcinoma (NPC) and acts as an oncogene in tumorigenesis. However, the mechanism of LMP1 as a proto-oncogene in nasopharyngeal carcinoma is still unclear. Two sequence-specific shRNAs 1 and 2 were designed to target the different nucleotide loci of EBV latent antigen LMP1 gene and a series of in vivo and in vitro experiments were performed to investigate the therapeutic effect of sequence-specific shRNAs targeting LMP1 and its related molecular mechanisms in EBV-positive NPC. LMP1-shRNA2 generated a truncated LMP1 mRNA and protein, whereas LMP1-shRNA1 completely blocked LMP1 mRNA and protein expression. Both LMP1-shRNAs inhibited the proliferation and migration of NPC cells overexpressing LMP1 (NPC-LMP1) as well as the NPC-associated myeloid-derived suppressor cell (MDSC) expansion in vitro. However, LMP1-shRNA2 maintained the immunogenicity of NPC-LMP1 cells, which provoked MHC-class I-dependent T cell recognition. LMP1-shRNAs inhibited tumor growth in nude mice but did not reach statistical significance compared to control groups, while the LDH nanoparticle loaded LMP1-shRNAs and the antigen-specific T cells induced by NPC-LMP1 cells treated with LMP1-shRNA2 significantly reduced tumor growth in vivo. LMP1-RNAi-based anti-tumor therapy could be a new hope for the clinical efficacy of RNAi treatment of tumors like NPC.

Research progresses on NLRP3 inflammasomes-induced anti-tumor immunity / 药学学报

More and more studies have shown that NOD-like receptor protein 3 (NLRP3) inflammasome has become the regulatory factor of inflammatory response and protective immunity, and the assembly and activation of NLRP3 inflammasomes are closely related to the anti-tumor immunity effect. Depending on the cell type and stimuli, activation of the NLRP3 inflammasome can induce immune cells to become polarized, hyperactive, or pyroptotic, releasing interleukin (IL)-1β and IL-18, which leads to cascade immune or inflammatory responses, and its role in tumor immunity has received extensive attention. Here, we review the mechanisms of the NLRP3 inflammasome enhancing CD8+ T cells-mediated anti-tumor immunity by inducing the pyroptosis of tumor cell, the pyroptosis or hyperactive state of dendritic cells (DCs), and the pyroptosis or polarization of the macrophages. Different anti-tumor immune roles of NLRP3 inflammasome activation in tumor cells and immune cells provide new directions for future research and may influence the development of next-generation immunotherapy.

Tetrahedral DNA nanostructures synergize with MnO2 to enhance antitumor immunity via promoting STING activation and M1 polarization

Stimulator of interferon genes (STING) is a cytosolic DNA sensor which is regarded as a potential target for antitumor immunotherapy. However, clinical trials of STING agonists display limited anti-tumor effects and dose-dependent side-effects like inflammatory damage and cell toxicity. Here, we showed that tetrahedral DNA nanostructures (TDNs) actively enter macrophages to promote STING activation and M1 polarization in a size-dependent manner, and synergized with Mn2+ to enhance the expressions of IFN-β and iNOS, as well as the co-stimulatory molecules for antigen presentation. Moreover, to reduce the cytotoxicity of Mn2+, we constructed a TDN-MnO2 complex and found that it displayed a much higher efficacy than TDN plus Mn2+ to initiate macrophage activation and anti-tumor response both in vitro and in vivo. Together, our studies explored a novel immune activation effect of TDN in cancer therapy and its synergistic therapeutic outcomes with MnO2. These findings provide new therapeutic opportunities for cancer therapy.

Research Progress on Hyperthermia and Anti-Tumor Immunity / 肿瘤防治研究

In recent years, with the development of comprehensive tumor therapy, hyperthermia has become one of the important means of cancer treatment. A large number of studies have shown that the removal of tumor cells depends on exogenous treatment methods and the body's own anti-tumor immune status. Hyperthermia cannot only directly kill tumor cells but also activate the body's immunity to exhibit an anti-tumor effect. In recent years, with the deepening of tumor research, hyperthermia has been able to create a type I tumor microenvironment with PD-L1 overexpression and enrichment of tumor-infiltrating lymphocytes, complementing the enhancement of immune checkpoint inhibitors. Hyperthermia combined with immunotherapy may offer a new perspective in cancer treatment. The mechanism of tumor hyperthermia and anti-tumor immunity and its clinical application have aroused great interest and become a new research field. This article reviews the relationship between tumor hyperthermia and anti-tumor immunity.

Astragalus polysaccharide improves anti-tumor immunity mediated by macrophages and natural killer cells in mice / 中华微生物学和免疫学杂志

Objective To evaluate the regulatory effects of Astragalus polysaccharide (APS) on macrophage polarization and NK cell-mediated anti-tumor responses in mice. Methods C57BL/ 6 mice were injected intraperitoneally with APS once a day for seven consecutive days. Activation of immune cells was then induced by intraperitoneal injection of polyinosinic-polycytidylic acid (Poly I : C) 24 h after the APS intervention. Peritoneal macrophages were collected 24 h after induction to analyze the status of polari-zation and the production of nitric oxide (NO). Cytotoxicity and exocytosis of activated NK cells were meas-ured to assess the effector functions of these cells. NK cell activities induced by NKG2D were studied in the absence of the whole JNK or JNK2 signaling pathway. Results Intraperitoneal injection of APS promoted the polarization of macrophages induced by tumor cells in mice, and enhanced the cytotoxicity of NK cells to tumor cells. However, APS was in need of the involvement of appropriate stimulatory factors to have regula-tory effects. Complete inhibition of JNK signaling pathway dramatically reduced the effector functions of NK cells, which could not be recovered by APS administration. Conclusions APS was involved in the regula-tion of anti-tumor innate immunity through enhancing the M1-polarization of macrophages and improving the effector functions of NK cells. This study might to some extent elucidate the mechanism of APS in immune regulation and anti-tumor immunity.

Anti-tumorimmune effects of WT1 polypeptide vaccine on SCID mice with xenografted human monocytic leukemia / 西安交通大学学报(医学版)

Objective: To study the anti-tumor immune effects of WT1 peptide vaccine in SCID mice with xenografted human monocytic leukemia. Methods: Twenty-four hours after intraperitoneal injection of human peripheral blood lymphocytes, the xenograft human monocytic leukemia model in SCID mice was established by subcutaneous inoculation of THP1 cells. The mice were randomly divided into three groups with eight mice in each. Blank control group was vaccinated with incomplete Freund's adjuvant (IAF). Helper T cell epitope group was vaccinated with helper T cell epitopes and IAF. WT1 group was vaccinated with WT1 peptide, helper T cell epitopes and IAF. When the tumor volume grew to 100 mm3, intraperitoneal injection of vaccine components started. The SCID mice were killed 14 days after vaccination. LDH release method was adopted to detect the specific CTL killing activity of spleen cells. Histological characteristics of tumor tissue were observed under microscope after HE staining. Flow cytometry was used to test the levels of peripheral blood CD3+/CD4+T cells, CD3+/CD8+T cells and CD4+CD25+ Treg cells. ELISA method was applied to detect the levels of serum immunoglobulin, IL-2, γ-interferon, TGF-β and IL-10. Results: The xenograft human monocytic leukemia model was successfully established in SCID mice and tumor developed in all the SCID mice. In WT1 group, the activity of mouse spleen cells on THP1 cells was significantly higher than that in helper T cell epitope group and control group (P<0.05). The mean weight and volume of tumor were significantly lower in WT1 group than in helper T cell epitope group and control group (P<0.05). A large amount of tumor cell degeneration and necrosis was observed under the microscope in WT1 group mice and few tumor cells survived. Peripheral blood levels of CD3+/CD4+T cells, CD3+/CD8+T cells, IgG, IFN-γ and IL-2 were all higher in WT1 group than in helper T cell epitope group and control group (P<0.05). However, peripheral blood levels of CD4+/CD25+Treg cells, TGF-β and IL-10 were all lower in WT1 group than in helper T cell epitope group and control group (P<0.05). Conclusion: WT1 polypeptide vaccine can effectively produce anti-tumor immunity and kill leukemia cells in SCID mice with exnografted human monocytic leukemia.

Research progress on the anti-tumor immunity of Th9 cells and its mechanism / 中国肿瘤临床

As a newly identified T helper cell subset, Th9 plays an important role in anti-tumor immunity. Th9 can be differentiated from CD4+T cells that have been induced by TGF-beta and IL-4. In addition, other CD4+T helper cell subsets can be developed to Th9 cell in particular situations, thereby showing its plasticity. Results of animal experiments have indicated that Th9 inhibits tumor growth and plays a significant role in anti-tumor immunity by secreting related cytokines such as IL-9. A few cytokines and molecules can regu-late the differentiation and development of Th9 cells in different signaling pathways. This review will focus on the production, anti-tu-mor immunity, related mechanism, and signaling pathways of Th9 cells, thereby providing a new field of vision and idea for anti-tumor therapy in the future.

Membrane-bound p35 Subunit of IL-12 on Tumor Cells is Functionally Equivalent to Membrane-bound Heterodimeric Single Chain IL-12 for Induction of Anti-tumor Immunity

In this study, we compared two different tumor cell vaccines for their induction of anti-tumor immunity; one was a tumor cell clone expressing a membrane-bound form of IL-12 p35 subunit (mbIL-12 p35 tumor clone), and the other was a tumor clone expressing heterodimeric IL-12 as a single chain (mb-scIL-12 tumor clone). The stimulatory effect of mb-scIL-12 on the proliferation of ConA-activated splenocytes was higher than that of mbIL-12 p35 in vitro. However, the stimulatory effect of mbIL-12 p35 was equivalent to that of recombinant soluble IL-12 (3 ng/ml). Interestingly, both tumor clones (mbIL-12 p35 and mb-scIL-12) showed similar tumorigenicity and induction of systemic anti-tumor immunity in vivo, suggesting that tumor cell expression of the membrane-bound p35 subunit is sufficient to induce anti-tumor immunity in our tumor vaccine model.

Role and mechanism of Kupffer cells in anti-tumor immunity of hepatocellular carcinoma / 国际外科学杂志

As the biggest macrophage cells population in human body and the most important immune cells in the liver,Kupffer cells play a very important role in infection,inflammation,lipid metabolism and liver transplantation,and regulates various physiological and pathological processes.However,little is known about the role and mechanism in the tumorigenesis and tumor progression of Kupffer cells which as a kind of such important immune cells.In this paper,we summarized published researches and our experimental results about Kupffer cells,and reviewed the relationship between Kupffer cells and hepatocellular carcinoma from aspects of phagocytosis,secretary and antigen presentation.We hold that,at the early age of liver diseases,Kupffer cells inhibit tumorigenesis of hepatocellular carcinoma by its functions of phagocytosis,secretary and antigen presentation;however,when inflammation persists,Kupffer cells could induce tumorigenesis of hepatocellular carcinoma by secretary mechanism.

Human dendritic cells transfected with MUC1 mRNA induce lethal effect of cytotoxic T-lymphocytes on non-small cell lung cancer in vitro / 中国病理生理杂志

AIM:To investigate the specific anti-tumor effects of mature dendritic cells ( DCs) transfected with amplified mucin 1 ( MUC1) mRNA in vitro.METHODS:DCs separated and purified from the peripheral blood mononu-clear cells were induced in vitro and then identified by flow cytometry .pcDNA3.1(+)-MUC1 plasmid was constructed and was able to transcribe MUC1 mRNA in vitro.The MUC1 mRNA was transfected into DCs by electroporation .MUC1-trans-fected DCs were used to induce T cells to be cytotoxic T-lymphocytes .Quantitative real-time PCR was performed to assess MUC1 mRNA expression in transfected DCs .The proliferation of T cells was examined by MTT assay .The proportion of CD8 +cells in the T cells was determined by flow cytometry and the specific cytotoxicity was measured by LDH assay .The secretion of IFN-γwas detected by ELISA .RESULTS: The marker gene expression in the DCs transfected with MUC 1 mRNA was significantly increased compared with control group , peaking at 24 h.The transfection group showed the higher capacity to stimulate the proliferation of T cells compared with control group when the ratio of DCs to T cells was 1∶10.The proportion of CD8 +cells in transfection group was higher than that in control group .The lethal effect of special cytotoxic T-lymphocytes on target cells in transfection group was stronger than that in control group .The level of IFN-γin the cell su-pernatant of transfection group was higher than that in control group .CONCLUSION:DCs plus MUC1 mRNA by electri-cal transfection induces specific anti-tumor effects , which provides an experiment evidence of using MUC 1 as a target for immunotherapeutic strategy against non-small cell lung cancer .

Dendritic Cell (DC) Vaccine in Mouse Lung Cancer Minimal Residual Model; Comparison of Monocyte-derived DC vs. Hematopoietic Stem Cell Derived-DC

The anti-tumor effect of monocyte-derived DC (MoDC) vaccine was studied in lung cancer model with feasible but weak Ag-specific immune response and incomplete blocking of tumor growth. To overcome this limitation, the hematopoietic stem cell-derived DC (SDC) was cultured and the anti-tumor effect of MoDC & SDC was compared in mouse lung cancer minimal residual model (MRD). Therapeutic DCs were cultured from either CD34+ hematopoietic stem cells with GM-CSF, SCF and IL-4 for 14 days (SDC) or monocytes with GM-CSF and IL-4 for 7 days (MoDC). DCs were injected twice by one week interval into the peritoneum of mice that are inoculated with Lewis Lung Carcinoma cells (LLC) one day before the DC injection. Anti-tumor responses and the immune modulation were observed 3 weeks after the final DC injection. CD11c expression, IL-12 and TGF-beta secretion were higher in SDC but CCR7 expression, IFN-gamma and IL-10 secretion were higher in MoDC. The proportion of CD11c+CD8a+ cells was similar in both DC cultures. Although both DC reduced the tumor burden, histological anti-tumor effect and the frequencies of IFN-gamma secreting CD8+ T cells were higher in SDC treated group than in MoDC. Conclusively, although both MoDC and SDC can induce the anti-tumor immunity, SDC may be better module as anti-tumor vaccine than MoDC in mouse lung cancer.

Herpesvirus entry mediator: A switch in immune response and its role in anti-tumor immunity / 第二军医大学学报

The interaction between co-stimulatory ligands and their receptors of T cells and antigen presenting cells is crucial for the activation or resting of the immune cells. The tumor necrosis factor receptor superfamily and CD28-B7 family contain many such regulatory molecules. Herpesvirus entry mediator (HVEM), also named as tumor necrosis factor superfamily member 14, is noted for its pivotal role in regulating immune responses through binding LIGHT as a ligand to develop T-cell immunity, and in interacting with B and T lymphocyte attenuator (BTLA) as a receptor to negatively regulate T-cell responses. In antitumor immunity, increasing amount of evidence demonstrates that HVEM is an indispensable receptor on lymphocyte for LIGHT to co-stimulate tumor antigen-specific CTL. This article discusses the role of HVEM in regulating immune response and antitumor-immunity.

Investigation on the anti-tumor effect and mechanisms of the glycosyl phosphatidylinositol modified routine IL-21 tumor vaccine / 中华微生物学和免疫学杂志

Objective To construct the murine IL-21 (mIL-21) tumor vaccine modified by glyco-syl phosphafidylinositol(GPI), and to evaluate its anti-tumor effect and mechanisms. Methods The IL-21-GPI gene was acquired by overlap PCR and inserted into PeDNA3.1. The recombinant plnsmid pcDNA3.1/ IL-21-GPI was transformed into cell B16F10, and the expression of mIL-21 on cell membrane was deter-mined by cell indirect immumofluorescence and flow cytometry (FCM). The bioactivity of mIL-21 was iden-tiffed according to its effects on the proliferation of mouse spleen cells. The anti-tumor effect was evaluated depending on the tumor size and the survival of tumor-beating mice after the tumor vaccine was inoculated into C57BL/6 mice. And the activity of cell-mediated immunity in immunized mice was detected at the same time. Results The recombinant plasmid pcDNA3.1/IL-21-GPI was correctly constructed, which could ex-press mIL-21 binding the membrane with good bioactivity. The vaccine had good anti-tumor effect, and the cell-mediated immunity had been improved in immunized mice. Conclusion The GPI modified mIL-21 tumor vaccine with anti-tumor activity was constructed successfully, which provided a good foundation for studying anti-tumor immunity and therapy in future.

B Cells Transduced with HPV16 E6/E7-expressing Adenoviral Vector Can Efficiently Induce CTL-dependent Anti-Tumor Immunity

BACKGROUND: Human papillomavirus (HPV) infection is responsible for cervical cancer, a common cancer in women. Since HPV infection and cancer development are controlled by the host immune system, immunotherapy against HPV can be helpful in preventing or treating HPV-associated cervical cancer. Two oncoproteins of HPV16, E6 and E7, are promising targets for immunotherapy against cervical cancer, because they are constitutively expressed in cervical cancer. METHODS: Since cellular vaccines using B cells as well as dendritic cells offer an efficient approach to cancer immunotherapy, we opted to use B cells. We evaluated the immunogenicity and anti-tumor effects of a B cell vaccine transduced with HPV16 E6/E7-expressing adenovirus. RESULTS: Vaccination with HPV16 E6/E7-transduced B cells induced E6/E7-specific CD8+ T cell-dependent immune responses and generated anti-tumor effects against E6/E7-expressing TC-1 tumor. The anti-tumor effect induced by this B cell vaccine was similar to that elicited by DC vaccine, showing that B cells can be used as an alternative to dendritic cells for cellular vaccines. CONCLUSION: Thisstudy has shown the feasibility of using B cells as immunogenic APCs and the potential for developing prophylactic and therapeutic vaccines against HPV-associated cervical cancer using a B cell vaccine transduced with adenovirus expressing HPV16 E6/E7.