Injection Of Immature Dendritic Cells Research Articles

CTLA-4 Blockade Enhances Antitumor Immunity of Intratumoral Injection of Immature Dendritic Cells into Irradiated Tumor in a Mouse Colon Cancer Model

Dendritic cells (DCs)-based cancer immunotherapy has been used various strategies to inhibit immune suppressive mechanisms. CD25 antibodies and cyclophosphamide are well-studied immunomodulators through inhibition of regulatory T cells (Treg) and a blockade the immune-checkpoint molecule, cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) was recently targeted for immunomodulation. We used anti-CTLA-4 antibody, which is known to induce effective antitumor immunity by facilitating tumor-specific T-cell activation and suppressing Treg cells, as useful immunomodulator to provide a potentiating effect in the intratumoral injection of immature DCs (iDCs) into the irradiated tumor (IR/iDC). Ionizing radiation (IR) was applied at a dose of 10 Gy to the tumor on the right thigh of mice. Then, iDCs were intratumorally injected into the irradiated tumor. Anti-CTLA-4 antibody (100 µg/mouse) was administered intraperitoneally to mice on the same day with every iDCs injection. The growth of distant tumors was inhibited by IR/iDC and this effect was significantly augmented by combination treatment of anti-CTLA-4 antibody. Furthermore, the survival rate of tumor-bearing mice improved more by the combination treatment of anti-CTLA-4 antibody and IR/iDC compared with other groups. It was related to the increased tumor-specific interferon-γ-secreting T cells and CTL activity. Therefore, our results demonstrated that immunomodulator such as anti-CTLA-4 antibody enhances antitumor immunity of intratumoral injection of iDCs into irradiated tumor and suggested a new strategy to get more clinical benefits for cancer treatment.

Improvement of Antitumor Effect of Intratumoral Injection of Immature Dendritic Cells Into Irradiated Tumor by Cyclophosphamide in Mouse Colon Cancer Model

Recently, chemotherapy and radiotherapy are known to directly affect some immunosuppressive barriers within a tumor microenviroment. We used cyclophosphamide (CTX), which is known to enhance the immune response by suppressing CD4+CD25+ regulatory T cells (Treg cells) when used at a low dose, as a chemotherapeutic agent to provide a synergic effect in the irradiation and dendritic cells (DC) combination therapy. Some previous studies observed that a single-dose CTX treatment significantly reduced the number of Treg cells in 3-5 days, however, the reduced Treg cells increased rapidly after 5 days. To overcome the disadvantages of a single-dose CTX, we used 30 mg/kg dose of CTX, which was treated intraperitoneally to mice 3 days before every immature DC (iDC) injection (known as "metronomic schedule CTX"). Irradiation was applied at a dose of 10 Gy to the tumor on the right thigh by a linear accelerator. Then, iDC was intratumorally injected into the irradiated tumor site. Growth of a distant tumor on the right and left flank was suppressed by an injection of iDC into the irradiated tumor, and this effect was increased by the metronomic schedule CTX. Also, combinations treated with the metronomic schedule CTX and ionizing radiation (IR)/iDC, showed the longest survival time compared with other groups. This antitumor immune response of IR/iDC was improved by metronomic schedule CTX and this result was associated with decreasing the proportion of CD4+CD25+ Treg cells and increasing the number of tumor-specific interferon-γ-secreting T cells. Our results demonstrated that metronomic schedule CTX improves the antitumor effect of immunization with an injection of DC s into the irradiated tumor.

Phase I trial of preoperative intratumoral injection of immature dendritic cells and OK‐432 for resectable pancreatic cancer patients

To determine the feasibility, safety and histological change of preoperative endoscopic ultrasound-guided fine-needle injection (PEU-FNI) of immature DCs (iDCs) with OK-432 in pancreatic cancer patients. Nine patients enrolled in the trial (DC group) and were compared with 15 patients operated on without iDC injection (non-DC group). Adverse events of PEU-FNI and postoperative complications were evaluated according to CTC-AE ver.3.0 and the Clavien-Dindo classification/ISGPF definition, respectively. Histological changes within the tumor and lymph nodes were evaluated by immunohistochemical examination of infiltrating inflammatory cells (CD4+, CD8+, Foxp3+ and CD83+). There were no severe toxicities following PEU-FNI, except for one transient grade 3 fever, and there were no significant differences in the incidence of postoperative complications between the two groups. Colliquative necrosis and diffusely scattered TUNEL-positive cells were observed at the injection sites. CD83+ cells significantly accumulated in the regional lymph nodes of the DC group as well as Foxp3+ cells in the regional and distant lymph nodes. The two DC group patients, one of which was stage IV with distant lymph node metastasis, survived more than 5 years without requiring adjuvant theraphy. PEU-FNI was feasible and safe, and further study needs to confirm and enhance antitumor responses.

Thioperamide induces CD4+ CD25+ Foxp3+ regulatory T lymphocytes in the lung mucosa of allergic mice through its action on dendritic cells

Background:Histamine is an important mediator in the development of allergic reactions. The biological effects of histamine are mediated through four histaminergic receptors. In recent years, an important role has been assigned to the proinflammatory functions of histamine regarding the H4 receptor. Previously, we have demonstrated that injection of immature dendritic cells treated with histamine into allergic mice promotes an increase in CD8+ Tc2 lymphocytes, which are involved in the worsening of allergy symptoms during the chronic phase of the disease. The aim of this study was to evaluate the role of the H3/H4 receptor antagonist, thioperamide, in allergy.Methods:Ovalbumin-allergized mice and nonallergized mice were injected with phosphate-buffered saline, dendritic cells, or thioperamide-treated dendritic cells. After treatment, the lungs of the mice were obtained and analyzed for changes in the populations of dendritic cells and T lymphocytes, as well as the expression of H and H4 receptors in mononuclear lung cells.Results:We found an increase in regulatory T cells in the lungs of allergic mice intratracheally injected with dendritic cells which had their H3/H4 receptors blocked with thioperamide. We also found an increase in the production of interleukin-10 by dendritic cells of the lung. Finally, we observed a decrease in serum levels of specific anti-IgE and a reduction of eosinophils in bronchoalveolar lavage from allergic mice.Conclusion:Thioperamide induces a significant improvement in symptoms of allergic reaction perhaps via induction of regulatory T lymphocytes. These findings may become relevant in the understanding of type 1 hypersensivity reactions.

Cyclophosphamide Potentiates the Antitumor Effect of Immunization with Injection of Immature Dendritic Cells into Irradiated Tumor

Growth of a tumor on the left flank was suppressed by direct injection of immature DCs (iDCs) into the irradiated tumor on the right thigh (IR/DC). This antitumor immune effect of IR/DC was enhanced by pretreatment with CTX (CTX+IR/DC) and this effect was related with increased number of tumor-specific IFN-γ secreting T cells and decreased ratio of CD4+CD25+/CD4+ T cells. The treatment with CTX+IR/DC increased or decreased the levels of IL-2 or IL-10, respectively. These results demonstrated that antitumor effect of IR/DC could be augmented by pretreatment with low-dose CTX, suggesting a new antitumor therapeutic modality of chemoradioimmunotherapy.

Combining Conventional Therapies with Intratumoral Injection of Autologous Dendritic Cells and Activated T Cells to Treat Patients with Advanced Cancers

Dendritic cells (DCs) are potent antigen-presenting cells that have been used in cancer immunotherapy. To take advantage of the ability of DCs to acquire antigenic materials from their environment and generate primary as well as recall immune responses, 37 patients with advanced cancers were enrolled in a series of protocols based on direct intratumoral injection of immature DCs. To augment antigen uptake and antitumor immune response, DC injection was combined with radiotherapy or chemotherapy and/or injection of activated T cells. Treatments were well tolerated with no adverse reactions. Clinical responses were based on Response Evaluation Criteria in Solid Tumors, with the majority of patients showing stable disease. One of two patients who also received local radiation achieved a sustained complete response at injected and metastatic sites. The clinical responses observed in cancer patients with advanced disease suggest potential effectiveness of combination strategies and establish the basis for the current treatment protocol that is underway.

Melanoma and Lymphoma Rejection Associated With Eosinophil Infiltration Upon Intratumoral Injection of Dendritic and NK/LAK Cells

Dendritic cells (DCs) are promising tools for tumor immunotherapy. Their efficacy in the tumor environment increases when tumor cells die as a consequence of chemo/radiotherapy or when local stimuli promoting DC maturation and function are available. Dying tumor cells could represent a source of tumor antigens, which DCs cross-present to tumor-specific T cells. The outcome of cross presentation is in turn determined by the maturation state of DCs. Natural killer (NK)/lymphokine-activated killer (LAK) cells injected into growing tumors could both provide a source of dying cells for cross-presentation and deliver stimuli for DC maturation. Here, we report that NK/LAK cells recognized and killed in vivo major histocompatibility complex class I(low) highly tumorigenic, nonimmunogenic B16F1 melanoma cells when injected into exponentially growing neoplastic lesions. The simultaneous injection of immature DCs was required to heal animals. Similar results were obtained injecting NK/LAK cells and DC into growing Raucher leukaemia virus induced cell line lymphomas. Cured mice failed to reject other implantable tumors, and developed a specific cytotoxic response against the original neoplasm; moreover, they developed a long-lasting memory, and were protected against further challenges with living tumor cells only when both cell populations were introduced. The response associated to the preferential recruitment within tumors of eosinophils. The simultaneous injection in solid tumors of DCs and NK/LAK cells represents an attractive approach for antineoplastic immunotherapeutic strategies.

Combined treatment with immunotherapy and chemotherapy using endoscopic ultrasonography guided injection for locally advanced pancreatic carcinoma

13503 Background: Dendritic cells (DCs) play a pivotal role in T cell-mediated immunity. Usually, mature DCs were cultured using resected tumor tissue, but for inoperable cases, this method is impractical. The injection of immature DCs into the tumor after appropriate chemotherapy is reasonable, if DCs come to maturity capturing the specific cancer antigen . The aim of this study is to assess the toxicity and efficacy of combined treatment with immunotherapy and chemotherapy for locally advanced pancreatic carcinoma. Methods: Five patients with pathologically confirmed pancreatic ductal carcinoma using EUS-FNA were enrolled, median age 56 years (range, 46–70 years). All cases without distant metastasis were diagnosed as surgically unresectable . Patients underwent leukapheresis, immature DCs were prepared from peripheral blood by a culture with granulocyte macrophage colony-stimulating factor and interleukin 4. Lymphokine-activated killer (LAK) were also prepared from peripheral blood. Immature DCs were injected biweekly in the mass by endoscopic ultrasound-guided fine needle injection (EUS-FNI), LAK were administered intravenously. Patients received the treatment of gemcitabine 1000 mg / m2 by intravenous injection 3 days before the immunotherapy. One course with 6 times combined therapy was continued until the judgment of progressive diseases (PD) was given. The toxicity and efficacy of this treatment were assessed. We also assessed whether tumor associated antigen (TAA)-specific IFN-?producing cells increase after treatment. Results: Hematological toxicity occurred in one case, leucopenia of grade 2. No severe toxicities of grade 3 to 4 occurred. One had a partial response (PR), stable disease (SD) was observed in 2 patients for more than 6 months (long-term SD). PR patient could undergo curative operation after this therapy. The number of TAA-specific IFN-?producing cells in PR patient increased 12-fold higher than that seen before treatments. Conclusions: These results support the safety and efficacy of combined treatment with immunotherapy and chemotherapy for locally advanced pancreatic ductal carcinoma. This treatment may be a useful for the treatment of pancreatic ductal carcinoma. No significant financial relationships to disclose.

Combined Treatment with Immunotherapy and Chemotherapy Using Endoscopic Ultrasonography: A Phase 1 Trial As First-Line Treatment in Patients with Locally Advanced Pancreatic Carcinoma

Aim: Dendritic cells (DCs) play a pivotal role in T cell-mediated immunity and have been shown to induce cytotoxic T-cell (CTL) responses against tumor antigens in vitro and vivo. Usually, mature DCs were cultured using resected tumor tissue, but for inoperable cases, this method is impractical. Dying tumor cells or tumor cell lysates caused by anticancer agent may be an antigen specific for patient's cancer. The injection of immature DCs into the tumor after appropriate chemotherapy is reasonable, if DCs come to maturity capturing the specific cancer antigen and arrive at lymph nodes which produce CTL.

Spotlight

Yang et al., pp. 495–499 The anti-diabetic drug troglitazone (TGZ), a PPAR-gamma agonist, enhances in vivo tumor formation in mouse models of human colon cancer, independent of pre-existing mutational events. Over a period of 6 months, the authors fed the troglitazone (TGZ) to two mouse strains one wild-type and one predisposed to intestinal genetically altered strain that rarely develops colonic tumors. They observed an increase in colonic tumor development in both strains. Effects of PPAR-gamma agonists on colon cancer remain highly controversial. Although PPAR-gamma activation has been shown to inhibit prostate and breast cancers, PPAR-gamma agonists have been shown to inhibit colon cancer growth as well as promote it, in different experiments. In the current study, researchers observed an increase in flat colonic adenomas, believed to be particularly aggressive. The results support the view that activated PPAR-gamma promotes colon cancer in mutant mice and demonstrate for the first time that normal mice also respond the same way. Normal mice fed TGZ for 6 months developed aggressive colon tumors. Zelmanowicz et al., 599–605 Familial aggregation of cervical cancer has been reported in various studies, suggesting that family history increases risk of disease. Yet it remains unclear whether familial aggregation results from genetic predisposition or shared environmental exposure and lifestyle factors. The current study examined data from two large case-control studies, one in the United States and one in Costa Rica, and concluded that a family history of cervical cancer in first-degree relatives appears to be associated with increased risk for cervical intraepithelial neoplasia type 3 and squamous cell carcinoma of the cervix, but not for adenocarcinomas. In the Costa Rican study, the association persisted in analyses limited to women known to be exposed to oncogenic types of HPV, indicating that shared environmental risk does not fully explain the association.Whereas the nature of familial aggregation studies makes it difficult to distinguish between the effects of genetic and shared environmental factors, previous work showing stronger familial effects among biological relatives compared with adoptive or half-relatives provides an important context in which to place these new findings. Evidence of an association between HLA polymorphisms and cervical cancer risk, previously reported, also serves to strengthen the case for the involvement of genetic factors. Tanaka et al., pp. 624–633 Dendritic cells can be used to increase the effectiveness of targeted heat in battling tumors, according to a new study on melanoma in rats. In earlier work, Tanaka and colleagues showed that heat treatment could be targeted to tumor cells in rats with minimal damage to normal cells. They used magnetic nanoparticles that generate heat in an alternating magnetic field and developed liposomes that preferentially concentrated the nanoparticles in tumor cells. Upon application of the magnetic field, the heat that was generated shrank the tumors containing the nanoparticles. This hyperthermia system also induced antitumor immunity, mediated by HSP70, which immunizes the rats upon release from the dying tumor cells. The researchers suspected that a dendritic cell-based vaccine could be a powerful weapon against malignant tumors if the cells can be induced to take up the antigen efficiently. As dendritic cells mature, they lose the ability to take up antigens, and it can be difficult to obtain enough tumor antigen from the patient. One way around this problem is to inject immature dendritic cells into the tumor. Hence, the authors decided to try injecting immature dendritic cells into tumors releasing HSP70 after heat treatment in hopes that this would magnify the immune response. They observed that the heated tumor cells induced dendritic cell maturation, and that the injection of immature dendritic cells in combination with the targeted heat induced antitumor immunity, suggesting that the combination approach could be of value to patients with advanced malignancies.

Endoscopic Ultrasound-Guided Fine Needle Injection of Immature Dendritic Cells into Advanced Pancreatic Carcinoma Refractory to Gemcitabine: A Pilot Study

Background and Aim: Immunotherapy against cancer has been investigated using different type of immune cells and the crucial role of dendritic cells (DCs) for the induction of primary T-cell-dependent immune responses was established. Intratumorally injected immature DCs would acquire and process tumor antigens in situ, migrate to regional lymphoid organs, and initiate a significant tumor specific immune response. The aim of this pilot study is to determine the feasibility, safety and clinical response of endoscopic ultrasound (EUS)-guided fine needle injection (FNI) of immature DC into the pancreatic cancer that had progressed to a metastatic disease after repeated systemic administration of gemcitabine D. Patients and Methods: Six patients with unresectable pancreatic cancer that had been unsuccessfully treated with gemcitabine were enrolled: all 6 patients in stage IVb with multiple liver metastasis, in whom 2 with malignant ascites. Immature DCs were generated from peripheral monocytes of patients with granulocyte-macrophage-colony stimulating factor and interleukin-4. Patients received intratumoral injection of 10 billion or more immature DC at 2-3 sites using EUS-guided FNI. Physical and laboratory examinations were performed to assess potential vaccine toxicity. Clinical endpoints included CA 19-9, tumor response and survival. Results: All DC injections were well tolerated without any clinical toxicity. The level of CA19-9 was decreased in 3 patients, mixed responses was observed in 3 (2 with malignant ascites) and the median survival of patients was 8 months. Conclusion: Direct injection of immature DC into the pancreatic tumor resulted in the generation of a potent antitumor immune response as evidenced by decreased CA19-9 levels and prolonged survival. Therefore intratumoral DC injection is a viable alternative to peripheral DC vaccination therapy for unresectable pancreatic cancer.

Direct injection of immature dendritic cells into irradiated tumor induces efficient antitumor immunity.

Although there are several ways to load tumor antigens to DCs, in vitro preparation of tumor antigens and manipulation of DCs are usually required. Therefore, to develop a simple antitumor immunization method, we examined if direct injection of DCs into tumor apoptosed by ionizing IR could induce efficient antitumor immunity. Ionizing IR with 15 Gy induced apoptosis in tumor maximally after 6 hr. Injection of DCs i.t. into IR tumor induced strong cytotoxicity of splenocytes against tumor cells compared to i.t. injection of DCs or ionizing IR of tumor, both of which induced weak cytotoxicity. In an animal study, i.t. injection of DCs into IR tumor induced therapeutic antitumor immunity against a tumor established at a distant site. Moreover, when TNF-alpha or LPS was added as a danger/maturation signal to DC suspension before i.t. injection, antitumor immunity was significantly potentiated compared to a group treated with i.t. injection of DCs into IR tumor. Our results suggest that injection of DCs into tumor apoptosed by ionizing IR might be a simple and efficient method of immunization against tumor.

Injection of immature dendritic cells into adjuvant-treated skin obviates the need for ex vivo maturation.

A key and limiting step in the process of generating human monocyte-derived dendritic cells (DC) for clinical applications is maturation. In the setting of immunotherapy, DC are matured ex vivo by culturing them with various agents that mimic the conditions encountered at a site of inflammation. This study examined whether the ex vivo DC maturation step could be replaced by maturing DC in situ by injecting immature DC into sites pre-exposed to agents that induce a microenvironment conducive to in situ maturation of the injected DC. The hypothesis was that recapitulation of the physiological conditions occurring during pathogen infection would lead to optimal conditions for DC maturation, migration, and function. Murine immature DC injected into adjuvant (Adjuprime, poly-arginine, or Imiquimod)-pretreated skin exhibited lymph node migratory capacity comparable to and immunostimulatory capacity equal to or exceeding that of ex vivo matured DC. Acquisition of migratory capacity did not always correlate with enhanced immunostimulatory capacity. Immunostimulatory capacity was not enhanced when mature DC were injected into adjuvant-pretreated sites and remained below that seen with immature DC matured in situ. Immature DC injected into adjuvant-pretreated sites were more effective than mature DC in stimulating antitumor immunity in mice. (111)Indium-labeled human monocyte-derived immature DC injected into adjuvant (Imiquimod)-pretreated sites in cancer patients acquired lymph node migratory capacity comparable to ex vivo matured DC. This study shows that in situ maturation offers a simpler and potentially superior method to generate potent immunostimulatory DC for clinical immunotherapy.

Immunotherapy through injection of immature dendritic cells prevents collagen-induced arthritis

Immunotherapy through injection of immature dendritic cells prevents collagen-induced arthritis

A single injection of immature dendritic cells is able to induce antitumour response against a murine colon adenocarcinoma with a low apoptotic index

Dendritic cells can induce an immune response as competent antigen presenting cells. It has been reported that immature bone marrow derived dendritic cells are capable of inducing an immune response against tumours displaying significant apoptosis. It is still controversial, however whether immature dendritic cells can also induce an immune response against tumours with a low apoptotic index. C-26 adenocarcinoma cells were injected into the footpad of Balb/c mice. One million immature dendritic cells cultured in vitro using GM-CSF and IL-4 were injected into the tumour-bearing footpad on day 6 after tumour cell inoculation. Tumour volume was measured starting from day 5 after tumour cell inoculation. Mice were observed daily for survival. The growing tumours were characterized by a low apoptotic index. There was a statistically significant delay in the tumour growth and a significant prolongation of the survival time in DC treated group as compared with controls (p<0.05). Immature dendritic cells injected into the site of tumour growth are able to induce a potent antitumour response which leads to the retardation of the tumour growth and the prolongation of the life survival time. Here we show that even a single injection of immature dendritic cells is able to induce a significant immune response against tumours with low apoptotic index.

Antigen-bearing immature dendritic cells induce peptide-specific CD8+ regulatory T cells in vivo in humans

AbstractRegulatory T cells (TRs) can suppress the function of other effector T cells in the setting of autoimmunity, transplantation, and resistance to tumors. The mechanism for the induction of TRs has not been defined. We previously reported that an injection of immature dendritic cells (DCs) pulsed with influenza matrix peptide (MP) led 7 days later to antigen-specific silencing of effector T-cell function in the blood of 2 healthy human subjects. Here, we found that interferon-γ–producing effectors return by 6 months. Importantly, in mixing experiments, CD8+ T cells from the sample obtained 7 days after injection could suppress MP-specific effectors obtained before injection and those in recovery samples. This suppression or regulation was specific for the immunizing peptide (MP) and cell-dose dependent, and it required contact between the 2 samples. These data show the capacity of immature DCs to induce antigen-specific regulatory CD8+ T cells in humans.