Chimeric antigen receptor dendritic cells targeted delivery of a single tumoricidal factor for cancer immunotherapy.

BACKGROUND: Chimeric antigen receptor (CAR)-T cells have been used to treat blood cancers by producing a wide variety of cytokines. However, they are not effective in treating solid cancers and can cause severe side-effects, including cytokine release syndrome. TNFα is a tumoricidal cytokine, but it markedly increases the protein levels of cIAP1 and cIAP2, the members of inhibitor of apoptosis protein (IAP) family of E3 ubiquitin ligase that limits caspase-induced apoptosis. Degradation of IAP proteins by an IAP antagonist does not effectively kill cancer cells but enables TNFα to strongly induce cancer cell apoptosis. It would be a promising approach to treat cancers by targeted delivery of TNFα through an inactive adoptive cell in combination with an IAP antagonist. METHODS: Human dendritic cells (DCs) were engineered to express a single tumoricidal factor, TNFα, and a membrane-anchored Mucin1 antibody scFv, named Mucin 1 directed DCs expressing TNFα (M-DCsTNF). The efficacy of M-DCsTNF in recognizing and treating breast cancer was tested in vitro and in vivo. RESULTS: Mucin1 was highly expressed on the surface of a wide range of human breast cancer cell lines. M-DCsTNF directly associated with MDA-MB-231 cells in the bone of NSG mice. M-DCsTNF plus an IAP antagonist, SM-164, but neither alone, markedly induce MDA-MB-231 breast cancer cell apoptosis, which was blocked by TNF antibody. Importantly, M-DCsTNF combined with SM-164, but not SM-164 alone, inhibited the growth of patient-derived breast cancer in NSG mice. CONCLUSION: An adoptive cell targeting delivery of TNFα combined with an IAP antagonist is a novel effective approach to treat breast cancer and could be expanded to treat other solid cancers. Unlike CAR-T cell, this novel adoptive cell is not activated to produce a wide variety of cytokines, except for additional overexpressed TNF, and thus could avoid the severe side effects such as cytokine release syndrome.

Dendritic cell vaccination combined with irreversible electroporation for treating pancreatic cancer-a narrative review.

Background and Objective: Pancreatic ductal adenocarcinoma (PDAC) is 3rd most lethal cancer in the USA leading to a median survival of six months and less than 5% 5-year overall survival (OS). As the only potentially curative treatment, surgical resection is not suitable for up to 90% of the patients with PDAC due to late diagnosis. Highly fibrotic PDAC with an immunosuppressive tumor microenvironment restricts cytotoxic T lymphocyte (CTL) infiltration and functions causing limited success with systemic therapies like dendritic cell (DC)-based immunotherapy. In this study, we investigated the potential benefits of irreversible electroporation (IRE) ablation therapy in combination with DC vaccine therapy against PDAC. Methods: We performed a literature search to identify studies focused on DC vaccine therapy and IRE ablation to boost therapeutic response against PDAC indexed in PubMed, Web of Science, and Scopus until February 20th, 2023. Key Content and Findings: IRE ablation destructs tumor structure while preserving extracellular matrix and blood vessels facilitating local inflammation. The studies demonstrated IRE ablation reduces tumor fibrosis and promotes CTL tumor infiltration to PDAC tumors in addition to boosting immune response in rodent models. The administration of the DC vaccine following IRE ablation synergistically enhances therapeutic response and extends OS rates compared to the use of DC vaccination or IRE alone. Moreover, the implementation of data-driven approaches further allows dynamic and longitudinal monitoring of therapeutic response and OS following IRE plus DC vaccine immunoablation. Conclusions: The combination of IRE ablation and DC vaccine immunotherapy is a potent strategy to enhance the therapeutic outcomes in patients with PDAC.

Dendritic cell subsets and implications for cancer immunotherapy.

Dendritic cells (DCs) play a central role in the orchestration of effective T cell responses against tumors. However, their functional behavior is context-dependent. DC type, transcriptional program, location, intratumoral factors, and inflammatory milieu all impact DCs with regard to promoting or inhibiting tumor immunity. The following review introduces important facets of DC function, and how subset and phenotype can affect the interplay of DCs with other factors in the tumor microenvironment. It will also discuss how current cancer treatment relies on DC function, and survey the myriad ways with which immune therapy can more directly harness DCs to enact antitumor cytotoxicity.

Vaccination with DC-SIGN-Targeting αGC Liposomes Leads to Tumor Control, Irrespective of Suboptimally Activated T-Cells.

Cancer vaccines have emerged as a potent strategy to improve cancer immunity, with or without the combination of checkpoint blockade. In our investigation, liposomal formulations containing synthetic long peptides and α-Galactosylceramide, along with a DC-SIGN-targeting ligand, Lewis Y (LeY), were studied for their anti-tumor potential. The formulated liposomes boosted with anti-CD40 adjuvant demonstrated robust invariant natural killer (iNKT), CD4+, and CD8+ T-cell activation in vivo. The incorporation of LeY facilitated the targeting of antigen-presenting cells expressing DC-SIGN in vitro and in vivo. Surprisingly, mice vaccinated with LeY-modified liposomes exhibited comparable tumor reduction and survival rates to those treated with untargeted counterparts despite a decrease in antigen-specific CD8+ T-cell responses. These results suggest that impaired induction of antigen-specific CD8+ T-cells via DC-SIGN targeting does not compromise anti-tumor potential, hinting at alternative immune activation routes beyond CD8+ T-cell activation.

Fusion of NY-ESO-1 epitope with heat shock protein 70 enhances its induced immune responses and antitumor activity against glioma in vitro.

Background: Glioma is the most common tumor originating in the brain and is difficult to cure. New York esophageal squamous cell carcinoma 1 (NY-ESO-1) is a promising cancer testis antigen (CTA) for tumor immunotherapy, and heat shock proteins (HSPs) can promote the antigen presentation of chaperoned peptides. This study investigates the therapeutic potential of HSP70 and NY-ESO-1 epitope fusion protein for glioma. Methods: Recombinant HSP70 protein was purified and fused to NY-ESO-1 epitope to generate HSP70/NY-ESO-1 p86-94. NY-ESO-1 expression was induced in U251 glioma cells via 5-Aza-2'-deoxycytidine (5-Aza-CdR) treatment. Dendritic cells (DCs) loaded with HSP70/NY-ESO-1 p86-94 or NY-ESO-1 protein stimulated NY-ESO-1-specific cytotoxic T lymphocytes (CTLs). The killing effect of NY-ESO-1 specific CTLs on U251 cells was detected by lactate dehydrogenase (LDH). Results: 5-Aza-CdR successfully induced NY-ESO-1 expression in U251 cells. NY-ESO-1-stimulated CTLs lysed more significantly with NY-ESO-1-positive U251 cells than with NY-ESO-1-negative cells. The immune response stimulated by a DC-based vaccine of HSP70/NY-ESO-1 p86-94 fusion protein was significantly enhanced compared with that induced by NY-ESO-1 alone. Conclusions: These findings indicate that the HSP70/NY-ESO-1 p86-94 may significantly enhance CTLs-mediated cytotoxicity and targeting ability against NY-ESO-1-expressing tumors in vitro. 5-Aza-CdR treatment with HSP70 binding to tumor antigen is a new strategy for immunotherapy of the tumors with poor CTA expression.

The Regulation of Reactive Oxygen Species on Dendritic Cells / 中国生物化学与分子生物学报

Dendritic cells (DCs) are specialized antigen-presenting cells. Immature dendritic cells can be activated into mature dendritic cells by recognizing antigens, then the antigens are processed and pres-ented to T lymphocytes. DCs play a vital role in initiating immune response, regulating immune response and maintaining immune tolerance. Therefore, regulating the immune function of DCs can be used to treat diseases such as autoimmune diseases and tumors. With the deepening of research on the regulation of DCs, people have gradually realized that the existence of reactive oxygen species (ROS) in DCs is of great significance. ROS is a term of strong oxidizing reactive species, and the dynamic balance of its pro-duction and removal is the key to maintaining cell redox homeostasis. ROS of physiological level is an im-portant molecule involved in a variety of signal pathways, which can regulate cell growth, differentiation and different physiological and biochemical reactions. The changes in the level of ROS affect the state and function of cells. In addition, because there are many ways to produce ROS in the cell, the effects of dif-ferent sources of ROS on DCs are not usually the same; and even the same source of ROS may have dif-ferent effects when cells are in different states. This article summarized the influence of intracellular ROS changes and different sources of ROS on the differentiation, maturation and function of DCs, aiming to re-veal how ROS plays an important role in regulating the immune function of DCs. At the same time, this article also showed the urgent need for the in-depth study of ROS regulating the function of DCs, which may help the application of DCs immune regulation to a wider range of disease treatments.

Long-term efficacy of dendritic cell vaccines combined with cytokine-induced killer cells in the treatment of metastatic renal cell carcinoma / 中国肿瘤生物治疗杂志

@# Objective: To evaluate the long-term clinical efficacy and follow-up of dendritic cell (DC) vaccines in combination with cytokine-induced killer cell (CIK) treatment in metastatic renal cell carcinoma. Methods: From January 2011 to December 2013, 29 patients with metastatic renal cell carcinoma (pathologically confirmed as renal clear cell carcinoma) were treated by DC vaccines-CIK at the Department of Hematopoietic Stem Cell Transplantation, the Fifth Medical Center of Chinese PLA General Hospital. The 29 patients included 24 male and 5 female, with a median age of 57(32-81) years old. Mature DC vaccine was obtained by gene transfection technology and CIK cells were obtained by i n v i t r o culture; and DC vaccine-CIK was infused back to patients through lymphatic drainage area and vein by each course. Twelve patients received first line treatment, 6 patients received second line treatment after the disease progression by targeted drug therapy or cytokine therapy, and 11 patients received third-linetreatment or above. The long-term clinical efficacy and overall survival rate were evaluated. Results: The median follow-up time was 5 (1-7) years. Treatment cycle was over 2 (2-23) cycles. One case (3.4%) achieved complete remission, 9 cases (31%) achieved partial responses, 13 cases (44.8%) demonstrated stable disease over 3 months and 6 patients (20.7%) developed progressive disease. The objective response rate was 34.4%,and the disease control rate was 79.2%. Stable disease for more than one year realized in 19 cases (65.5%). The 1-, 3- and 5-year survival rates were 93.1% (27/29), 65.5% (20/29) and 51.7% (15 / 29), respectively. Neither the median progression-free survival (PFS) nor the median survival time was achieved. No adverse reactions above grade 3 were observed during treatment. Conclusion: DC vaccines-CIK therapy for the treatment of metastatic renal cell carcinoma is affirmative; it achieved good disease control and long-term survival with controllable safety, and prolonged the survival time for advanced renal cell carcinoma patients.

Inhibitory effects of DC vaccine sensitized with MAGE-3 combined with CpG ODN on bladder cancer BIU-87 cells / 中国肿瘤生物治疗杂志

@#Objective: To investigate the role of CpG ODN (CpG oligodeoxynucleotide) adjuvant in enhancing the anti-bladder cancer response induced by MAGE-3 (melanoma antigen gene -3) antigen and its molecular mechanism. Methods: Mononuclear cells were isolated from HLA-A2 type peripheral blood of healthy donors by Ficoll method to prepare mature DC by conventional means. DC surface markers were detected by flow cytometry. MTT assay was used to detect the promotion effect of DCs sensitized by different means (MAGE-3, CpGODN, MAGE-3+CpG ODN, irrelevant control antigen) on the proliferation of T lymphocytes and the killing effect of CTL on BIU-87 tumor cells. The tumor mass of nude mice bearing BIU-87 bladder cell xenograft were examined on Day 7 and 11 after CpG ODN+MAGE-3 sensitized DC treatment. The expression of Bcl-2/Bax protein was detected by Western blotting while the proliferation level of xenograft cells was detected by MTT assay. Results: DCs sensitized by CpG ODN combined with MAGE-3 antigenic peptides could promote the proliferation of T lymphocytes and significantly enhance the killing effect of CTLon target BIU-87 cells (P< 0.05). Compared with other sensitized DCs, in vivo experiments showed that 7 and 11 days after treatment, both the tumor volume and weight were significantly reduced (all P<0.05), and the proliferation ability of xenograft tumor was decreased (P<0.05). Compared with other sensitization means, CpG ODN+MAGE-3 especially exhibited obvious inhibitive effect on tumor growth on Day 11, and significantly promoted the proliferation of splenic monocytes of tumor bearing mice (P<0.01); moreover, Bcl-2 expression in xenograft tissues significantly decreased（P<0.01）while Bax expression significantly increased（P<0.05 or P<0.01）on Day 3 after treatment. Conclusion: CpG ODN can promote the inhibitory effect of MAGE-3 sensitized DC on bladder cancer BIU-87 cells, which will provide experimental basis for clinical application of DC vaccine in bladder cancer treatment.

Effect of PvMSP1 on differentiation,maturation and function of dendritic cells / 中国血吸虫病防治杂志

Objective To investigate the effects of Plasmodium vivax merozoite surface protein 1(PvMSP1)on differentia-tion,maturation and function of dendritic cells(DC)and the mechanisms of PvMSP1 on the activation of DC via toll like receptors (TLR). Methods DCs were incubated with different doses of PvMSP1(1.0,10.0,100.0μg/ml)in vitro. The changes of CD83, CD86,and HLA-DR on DC were detected by flow cytometry(FCM);the expressions of cytokine IL-10 and IL-12 of DC were mea-sured by ELISA;the expressions of TLR4 and TLR9 mRNA of DC were measured by RT-PCR;the proliferation induction to autol-ogous lymphocytes of DC was measured by MTT. Meanwhile,the untreated DC and LPS inducing DC were as the negative control and positive control,respectively. All the data were analyzed statistically. Results Compared with the untreated DC,the propor-tions of CD83,CD86 and HLA-DR on DC induced by LPS and PvMSP1 increased significantly(all P0.05). In the PvMSP1-treated group,the DC TLR4 mRNA production increased(P0.05);DC stimulated the proliferation of autologous lympho-cytes. Conclusion PvMSP1 enhances DC differentiation and maturation,and the mature DC induced by PvMSP1 has the ability of antigen presenting. The route for PvMSP1 inducing DC maturation might be TLR4 pathway rather than TLR9 pathway.

Enhanced CEA-specific Immune Responses by Tat-LLO Fusion Protein

BACKGROUND: Carcinoembryonic antigen (CEA) is well-known soluble tumor marker frequently detectable in peripheral blood of carcinoma patients and considered as good target for antigen-specific immunotherapy. However, it is known that the induction of immune response to CEA is very difficult because CEA is a self-antigen expressed in fetal cells and weakly expressed in normal colorectal epithelial cells. To enhance anti-tumor immunity specific for CEA, recombinant CEA protein was modified using listeriolysin O (LLO) for endosomal lysis and transactivator of transcription (Tat) domain for transducing extracellular proteins into cytoplasm. METHODS: After immunization using dendritic cells pulsed with Tat-CEA, both Tat-CEA and LLO, and both Tat-CEA and Tat-LLO, antibody titer to CEA and LLO, cytotoxic T lymphocyte activity and the frequency of IFN-gamma producing T lymphocytes were measured. RESULTS: Immunization using DC pulsed with both Tat-CEA and Tat-LLO protein showed the increasement of production of CEA-specific antibody in serum, cytotoxic T lymphocyte activity, the frequency of IFN-gamma secreting T cells, compared with DC pulsed with both Tat-CEA and LLO. Furthermore the ratio of CD8+ T cell to CD4+ T cell among CEA-specific T cells was increased in group pulsed with both Tat-CEA and Tat-LLO. CONCLUSION: These results suggested that DC vaccine using Tat-LLO could be used for the development of effective immunotherapy for the treatment of tumor.

Enhanced Induction of CEA Specific Tumor Immunity by TatCEA Fusion Protein

PURPOSE: The human carcinoembryonic antigen (CEA) is expressed in several tumor types, including colorectal cancer, and is a tumor-associated antigen used as a target for antigen-specific immunotheraphy. CEA is a self-antigen associated with development, expressed in fetal cells and rarely expressed in normal colorectal epithelial cells. The induction of immune response to CEA is very difficult. In this study, we attempted to increase the tumor immunity specific to CEA by using dendritic cells pulsed with fusion proteins of CEA and Tat (transactivator of transcription), which transduces extracellular proteins into cytoplasm and causes antigens to be presented with MHC class I pathway. METHODS: The Tat gene was amplified in the PNL4-3 HIV plasmid and then inserted into PCEP4 plasmid vector. The CEA gene was cloned from cDNA from LoVo human colorectal cell line and then amplified through polymerase chain reaction method. After cloning of PCEP4 plasmid vector, the dendritic cell was sensitized and internalized with CEA and Tat-CEA protein. Then the Western blot analysis of the expression of CEA in the gene-modified dendritic cell and the immunofluorescent staining of the expression of CEA in CEA or Tat-CEA-pulsed dendritic cell were performed. A detection of IFN-gamma-releasing CD8 cell and a cytotoxicity of T-cell were was assesed using ELISPOT assay. The Immunoglobulin (Ig) G isotypes were analyzed with enzyme-linked immunosorbent assay. The statistical significance was assessed using Students t-test. RESULTS: CEA pulsed in dendritic cells was distributed over the cell surface and TatCEA was observed in the cytoplasm. The cellular immune responses by immunization with dendritic cells pulsed with TatCEA (322/10(4) lymphocytes) were significantly increased compared with those with CEA (244/10(4) lymphocytes) by IFN-gamma ELISPOT assay (P<0.05). The cytotoxic T lymphocyte (CTL) activity using mouse T-cell, EL-4 pulsed peptide (EAQNTTYL) as target cells was 23.3+/-2.75% (E:T=1:100) in the CEA group and 22.9+/-2.23% (E:T=1:100) in the TatCEA group. In ELISA analysis of the IgG isotype, the titer of IgG2a and IgG3, representing Th1 immune response, was lower than that of IgG1, representing Th2 immune response, in both the CEA group and the TatCEA group. CONCLUSIONS: These results suggest that TatCEA could be used for the development of a tumor vaccine and cellular immunotherapy using CTLs induced in vitro.

Induction of CEA-specific Cytotoxic T Lymphocytes by Murine Dendritic Cells Expressing CEA

BACKGROUND: Carcinoembryonic antigen (CEA) is well-known soluble tumor marker frequently detectable in peripheral blood of carcinoma patients and considered as good target for antigen-specific immunotherapy. In this study, we used a replication-deficient adenovirus containing CEA to study CTL induction in vitro after adenovirus-mediated gene transfer into DC. METHODS: DC were obtained from mouse bone marrow and cultured with IL-4 and GM-CSF. For measuring CTL activity, splenocytes were harvested from the mice, which were immunized with DC that had been infected AdV-CEA or pulsed with CEA peptide. Untreated DC was used as a control. Splenocytes were re-stimulated in vitro with DC pulsed with CEA peptide for 7 days and CTL activity with CEA peptide-pulsed EL-4 cells were assessed in a standard 51Cr-release assay. The frequencies of antigen-specific cytokine-secreting T cell were determined with mIFN-gamma ELISPOT. RESULTS: DC infected with recombinant adenovirus expressing CEA induced CEA-specific CTL responses in vivo. Splenocyte induced from mice immunized with AdV-CEA-infected DC increase in the number of IFN-gamma secreting T cells compared with those from mice immunized with CEA peptide-pulsed DC. CONCLUSION: These results suggested that DC infected with recombinant adenovirus has advantages over other forms of vaccination and could provide an alternative approach vaccination therapies.

Induction,proliferation and functional study of specific anti-acute myeloid leukemia(AML) T cells / 中国免疫学杂志

Objective:To develop specific anti-AML T cells in vitro,and to study their biological characteristics and functions.Methods:Peripheral blood or bone marrow mononuclear cells (MNCs) were isolated from 12 patients with AML,and co-cultured with cytokine combinations in 96 well plates to be induced into dendritic cells (DCs).Cell morphology was observed under an inverted microscope during the first week and immunophenotype was detected by flow cytometry at day 7.Cytokine combination was replaced with high dose IL-2 at day 7 to promote specific anti-AML T cells.T cell phenotype was detected after 4 to 5 weeks.Lactate dehydrogenase (LDH) release assay was used to determine T cell killing activity.Results:After being cultured with cytokine combinations,the typical dendritic appearance with delicate membrane projections was observed.CD80,CD86 and HLA-DR markers were significantly upregulated(P

The effect of PA on the proliferation and maturation of cord blood derived DC in vitro / 中国药理学通报

Aim To study the effect of PA on the proliferation and maturation of cord blood derived DC in vitro. Methods The monocytes were isolated from human umbilical cord blood and cultured with PA, GM-CSF+IL-4+TNF-?(GTI), GTI+PA (GTIP), respectively. On day 7 of cultivation, the CD1a, CD83,HLA-DR and CD34 antigens expression of cells were analyzed by immunohistochemistry. Result The cells with typical morphological properties of DC can be observed with electron microscope among PA, GTI and GTIP groups. The CD1a and CD83 positive rates of PA group increased significantly, reaching 19.63%?3.61% and 14.52%?5.79% respectively, much higher than that of the control. In addition, compared with GIT group, the positive rate in GTIP group has increased remarkably. Conclusion PA does not only promote the proliferation and maturation of cord blood derived DC, but also cooperate with GTI to enhance the production of DC. PA is a useful activator of DC.

Enhancement of the cytotoxic effect of cytokine induced killers by dendritic cells pulsed with astragalus polysaccharides / 中国免疫学杂志

Objective:To observe the effects of Astragalus polysaccharides on antigen presentation of dendritic cells(DC).Methods:DC and CIK cells were generated by culturing PBMC of healthy blood donor.The typical DC and DC pulsed by Astragalus polysaccharides were co-cultured with CIK cells,respectively.Then the changes in the phenotypes of the DCs pulsed with Astragalus polysaccharides were determined.Cell surface markers were analysed by FACS method.IFN-? and IL-12 secreted by co-cultured cells were detected by ELISA.The cytotoxicity of effector cells on A549 cells in vitro were measured by MTT assays.Results:Astragalus polysaccharides could increase the expression of CD40,CD80 and HLA-DR on DC surface.The Astragalus polysaccharides pulsed DC-CIK cells resulted in an enhanced killing activity to A549 cells than that of unpulsd DC-CIK cells(P