Hyunah Lee

Combination therapy of renal cell carcinoma or breast cancer patients with dendritic cell vaccine and IL-2: results from a phase I/II trial

BackgroundTen cancer patients (Six renal cell carcinoma and four breast cancer patients) were treated in a phase I/II study with a vaccine composed of autologous dendritic cells (DCs) and IL-2 to evaluate the DC vaccine-related toxicity and antigen-specific immune alteration.MethodsCancer patients were treated twice with autologous CD34+ hematopoietic stem cell-derived, GM-CSF/IFN-γ-differentiated DCs pulsed with autologous tumor lysate and KLH, by 4-week interval. Following each subcutaneous injection of therapeutic DCs, low-dose (200 MIU) IL-2 was introduced for 14 consecutive days as an immune adjuvant. To determine the DC vaccine-induced immunological alterations, the KLH-specific lymphocyte proliferation, number of IFN-γ secreting T cells (ELISPOT assay), NK activity and the cytokine modulation were measured.ResultsCultured-DCs expressing HLA-DR, CD11c, CD83, and B7.1/B7.2 produced IL-12p70. After vaccination, the patients tolerated it. Clinical response was observed in one RCC patient as stable disease. However DC-vaccine related antigen-specific immune responses including peripheral blood lymphocyte proliferation and the number of IFN-r secreting cells were induced in six patients without clear correlation with clinical responses. Also NK activity was induced significantly in six patients after vaccination. DC vaccine-related decrease of TGF-β level or increase of IL-12p70 level and decline of CD4+CD25+ T cells were observed in three patients. However only in the RCC patient whose disease stabilized, combination of stimulatory as well as inhibitory immune alterations including induction of IFN-γ secreting T cell with reduction of CD4+ CD25+ T cell were correlated with clinical responses.ConclusionData indicated that DC vaccine combined with IL-2 is well tolerated without major side effects. DC vaccine induced the specific immunity against introduced antigen. Combinatorial alterations of immunological parameters indicating antigen-specific immune induction along with reduction of inhibitory immunity were correlated with clinical responses in DC vaccine treated patients.

A phase I/IIa study of adjuvant immunotherapy with tumour antigen-pulsed dendritic cells in patients with hepatocellular carcinoma.

Background:To date, no adjuvant treatment has been shown to have a clear benefit in patients with hepatocellular carcinoma (HCC). In this prospective phase I/IIa study, we evaluated the safety and efficacy of adjuvant dendritic cell (DC) therapy in HCC patients who received primary treatment for HCC.Methods:Twelve HCC patients who had no viable tumour after primary treatments were included. Dendritic cell vaccines pulsed with cytoplasmic transduction peptide-attached alpha-fetoprotein, glypican-3 and melanoma-associated antigen 1 recombinant fusion proteins were injected subcutaneously near to inguinal lymph nodes. Adverse effects, time to progression (TTP), and associated immune responses were evaluated after DC vaccination.Results:Nine of 12 patients had no tumour recurrence up to 24 weeks after DC vaccination. Among a total of 144 adverse events, 129 events (89.6%) were regarded as adverse drug reactions, all of which were grade 1 or 2. The majority of patients showed enhanced anti-tumour immune responses after DC vaccination. Recurrence-free patients exhibited relatively stronger anti-tumour immune responses than patients who developed recurrence after DC vaccination, as evidenced by lymphocyte proliferation and IFN-γ ELISPOT assays. The median time of TTP was 36.6 months in the DC-vaccination group and 11.8 months in the control group (hazard ratio, 0.41; 95% confidence interval, 0.18–0.95; P=0.0031 by log-rank test).Conclusions:Adjuvant DC vaccine for HCC was safe and well tolerated in phase I/IIa study, and preliminary efficacy data are encouraging to warrant further clinical study in patients with HCC after primary treatments.

Therapeutic DC vaccination with IL-2 as a consolidation therapy for ovarian cancer patients: a phase I/II trial

While ovarian cancer (OvCa) responds well to surgery and conventional chemotherapy, a high recurrence rate of advanced OvCa is observed. In this phase I/II study, 10 OvCa patients with minimal residual disease were treated with autologous dendritic cells (DCs) and IL-2 to evaluate the safety and feasibility of this therapeutic strategy and to characterize the antigen-specific immune alterations induced through this treatment. Approximately 4 months after initial debulking and chemotherapy, patients received two subcutaneous doses of autologous monocyte-derived DCs pulsed with autologous tumor lysate and keyhole limpet hemocyanin (KLH) at 4-week intervals. After each DC inoculation, low-dose (200 mIU) IL-2 was introduced for 14 consecutive days as an immune adjuvant. The vaccination was well tolerated. In three out of 10 patients, the inclusion status after the initial therapy showed the maintenance of complete remission (CR) after DC vaccination for 83, 80.9 and 38.2 months without disease relapse. One patient with stable disease (SD) experienced the complete disappearance of tumor after DC vaccination, and this status was maintained for 50.8 months until tumor recurrence. In two patients with partial response (PR) was not responding to DC vaccination and their disease recurred. In the three patients with disease free long-term survival, significant immune alterations were observed, including increased natural killer (NK) activity, IFN-γ-secreting T cells, immune-stimulatory cytokine secretion and reduced immune-suppressive factor secretion after DC vaccination. Thus, in patients with NED status and increased overall survival, DC vaccination induced tumor-related immunity, potentially associated with long-term clinical responses against OvCa.

The effects of statins on the clinical outcomes of Clostridium difficile infection in hospitalised patients

An association between exposure to statin drugs and favourable treatment outcomes for various types of infections has been established.

Combinatorial Therapy for Liver Metastatic Colon Cancer: Dendritic Cell Vaccine and Low-Dose Agonistic Anti-4-1BB Antibody Co-Stimulatory Signal

BACKGROUND The combination of dendritic cell (DC) vaccine and 4-1BB ligation may be a suitable choice of immunotherapy for incurable cancer. However, at anti-tumor effector doses over 100 μg, 4-1BB Ab ligation is toxic to CD4(+) T cells, thus limiting its therapeutic use. MATERIALS AND METHODS A liver metastatic colon cancer model was established by hepatic injection of CT26 cells into Balb/c mice. Intraperitoneal administration of 1 × 10(6)/200 μL/mouse therapeutic-DCs (tumor lysate pulsed-DCs, P-DCs) began on d 7 after tumor cell inoculation. A P-DC injection was performed twice within a 1-wk interval. Agonistic anti 4-1BB Ab was intraperitoneally injected on d 7, 9, and 11 after tumor cell inoculation. Animals were sacrificed on d 21, and tumor growth was determined by weighing the liver with the tumor. RESULTS In the 20 μg 4-1BB ligation group, significant induction of CD3(+)CD8(+) T cells was observed without toxicity to CD3(+)CD4(+) T cells. DC vaccine treatment induced tumor antigen-specific Th1 cytokine (IL-2 and IFN-γ) secretion from the splenic lymphocytes. Ligation of 4-1BB reduced the DC vaccine-related IL-10 secretion and regulatory T cell population. Compared with anti-tumor effect of DC vaccine or 20 μg 4-1BB Ab alone, the combination therapy significantly increased the tumor rejection power to the level observed with higher doses of 4-1BB Ab alone. The combination therapy did not induce high-dose 4-1BB-related toxicity with CD4(+) T cell reduction, but did significantly induce tumor antigen-specific IFN-γ secreting effector CD8(+) cytotoxic T cells. CONCLUSIONS The data from our study reveal the value of using a DC vaccine combined with as little as 20 μg 4-1BB Ab as an improved immunotherapeutic for cancer.

Heterogeneity of mucosal mast cell infiltration in subgroups of patients with esophageal chest pain

Although there is growing evidence that an increase in mucosal mast cells (MMCs) in the small and large intestine is associated with visceral hypersensitivity, few studies have evaluated MMCs in humans with esophageal symptoms. The aim of this study was to investigate esophageal MMC distribution in patients with non‐cardiac chest pain (NCCP) and to examine the association between the number of gut MMCs and other functional gastrointestinal disorders.

Immunogenic Cell Death Induced by Ginsenoside Rg3: Significance in Dendritic Cell-based Anti-tumor Immunotherapy

Cancer is one of the leading causes of morbidity and mortality worldwide; therefore there is a need to discover new therapeutic modules with improved efficacy and safety. Immune-(cell) therapy is a promising therapeutic strategy for the treatment of intractable cancers. The effectiveness of certain chemotherapeutics in inducing immunogenic tumor cell death thus promoting cancer eradication has been reported. Ginsenoside Rg3 is a ginseng saponin that has antitumor and immunomodulatory activity. In this study, we treated tumor cells with Rg3 to verify the significance of inducing immunogenic tumor cell death in antitumor therapy, especially in DC-based immunotherapy. Rg3 killed the both immunogenic (B16F10 melanoma cells) and non-immunogenic (LLC: Lewis Lung Carcinoma cells) tumor cells by inducing apoptosis. Surface expression of immunogenic death markers including calreticulin and heat shock proteins and the transcription of relevant genes were increased in the Rg3-dying tumor. Increased calreticulin expression was directly related to the uptake of dying tumor cells by dendritic cells (DCs): the proportion of CRT+ CD11c+ cells was increased in the Rg3-treated group. Interestingly, tumor cells dying by immunogenic cell death secreted IFN-γ, an effector molecule for antitumor activity in T cells. Along with the Rg3-induced suppression of pro-angiogenic (TNF-α) and immunosuppressive cytokine (TGF-β) secretion, IFN-γ production from the Rg3-treated tumor cells may also indicate Rg3 as an effective anticancer immunotherapeutic strategy. The data clearly suggests that Rg3-induced immunogenic tumor cell death due its cytotoxic effect and its ability to induce DC function. This indicates that Rg3 may be an effective immunotherapeutic strategy.

Systemic immunity of obese-diabetes model ( db/db ) mice

Obesity has recently been defined as a chronic inflammatory disease and is considered as a major cause of adult health problems including incurable diseases like diabetes and cancer. In this study, the systemic immunity, including the innate and adaptive immunity parameters, of naturally occurring (leptin receptor mutation) obesity-diabetes mice (db/db) was examined to increase our knowledge of these mice for obesity-related studies. Severe fatty liver with blood engorgement was observed in the db/db mice. Compared to background C57BL/6J mice, the adaptive immunity, as measured by mitogen-induced T and B cell proliferation and cytokine release, was significantly suppressed in db/db mice. However, significant upregulation of innate immune-inflammatory parameters including macrophage function and NK cell activity was observed in db/db mice without external stimulation. These data conclusively confirm the systemic immune-inflammatory micro-environment with suppressed adaptive immunity of db/db mice, which may cause the secondary obesity-related life-threatening diseases like diabetes or cancer.

Cellular Mechanism of Newly Synthesized Indoledione Derivative-induced Immunological Death of Tumor Cell

Background EY-6 is one of the newly synthesized indoledione derivatives to induce tumor cell-specific cell death. In this study, we investigated the mechanism of immunological death induced by EY-6 at mouse colon cancer cell as well as at the normal immune cell represented by dendritic cell. Methods C57BL/6 mouse syngeneic colon cancer cell MC38 was treated with EY-6, and analyzed by MTT for viability test, flow cytometry for confirming surface expressing molecules and ELISA for detection of cytokine secretion. Normal myeloid-dendritic cell (DC) was ex vivo cultured from bone marrow hematopoietic stem cells of C57BL/6 mice with GM-CSF and IL-4 to analyze the DC uptake of dead tumor cells and to observe the effect of EY-6 on the normal DC. Results EY-6 killed the MC38 tumor cells in a dose dependent manner (25, 50 and 100 µM) with carleticulin induction. And EY-6 induced the secretion of IFN-γ but not of TNF-α from the MC38 tumor cells. EY-6 did not kill the ex-vivo cultured DCs at the dose killing tumor cells and did slightly but not significantly induced the DC maturation. The OVA-specific cross-presentation ability of DC was not induced by chemical treatment (both MHC II and MHC I-restricted antigen presentation). Conclusion Data indicate that the EY-6 induced tumor cell specific and immunological cell death by modulation of tumor cell phenotype and cytokine secretion favoring induction of specific immunity eliminating tumor cells.

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-β secretion were higher in SDC but CCR7 expression, IFN-γ 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-γ 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.