Adoptive immunotherapy using autologous lymphocytes sensitized with HLA class I-matched allogeneic tumor cells.

A 29-year-old female breast cancer patient with multiple bone metastases (HLA-A2) was treated with adoptive transfer using autologous peripheral blood mononuclear cells (PBMCs) activated with the HLA-A2-matched allogeneic GC022588 gastric cancer cell line and interleukin-2 plus an immobilized anti-CD3 antibody culture system. The relief of bone pain in parallel with a decrease of serum carcinoembryonic antigen levels was obtained just after the administration of GC022588-activated effector lymphocytes, and a good quality of life was accomplished for 4 months. The GC022588-activated effector lymphocytes included 44% CD4+, 77% CD8+, and 26% CD4+CD8+ phenotypes, and expressed 25% killing activity against GC022588 stimulator cells at an E/T ratio of 50:1. T cell receptor (TCR) usage analysis for the effector cells showed oligoclonal expression of TCRVbeta1, 3, 9, and 11, especially TCRVbeta5.2, 12, 13.1 and 17, and their killing activity was significantly inhibited in the presence of anti-TCRalphabeta antibody and anti-TCRVbeta12 antibody. SSCP analysis revealed clonotypic bands of TCRVbeta12. These results suggest that shared antigens exist between breast and gastric adenocarcinomas. Allogeneic tumor cells can stimulate PBMCs to generate effector cells with selected TCRCDR3 usages that recognize tumor antigens. These effector lymphocytes may be good candidates for the adoptive immunotherapy of cancer.

Generation of tumor-reactive effector lymphocytes using tumor RNA-introduced dendritic cells in gastric cancer patients.

Anti-tumor effector cells were generated by stimulating peripheral blood lymphocytes with cultured dendritic cells (DCs) and mRNA extracted from the gastric cancer cell line MKN45 or ascites tumor cells of gastric cancer patients. DCs were generated from an adherent fraction of peripheral blood mononuclear cells (PBMCs) in the presence of GM-CSF and IL-4. mRNA was extracted from tumor cells and subjected to T7-amplification. The DCs were electroporated (150 V/150 microF) with amplified mRNA and used after maturation with TNF-alpha to stimulate PBMCs to generate tumor RNA-introduced DC-activated killer (TRiDAK) cells. It was found that tumor RNA could efficiently be introduced into cultured DCs by electroporation (55% efficiency, 78% viability), and tumor RNA-introduced DCs could reproducibly stimulate lymphocytes to be tumor-reactive TRiDAK cells. The TRiDAK cells expressed an IFN-gamma response specific for tumor cells, but not for normal cells. Mock DCs or normal cell RNA-introduced DCs did not induce any killer cells. RNA-specific recognition of the effector cells generated was demonstrated using an amplified EGFP-mRNA system. The tumor killing activity of TRiDAK cells was inhibited not only with the anti-HLA class I antibody but also with the anti-HLA class II antibody as well as the anti-TCR antibody. TRiDAK cells reactive with autologous tumor cells could be generated in a CEA-positive gastric cancer patient with malignant ascites, in whom effector cell generation using DCs and CEA peptides had failed. These results suggest that TRiDAK cell generation is safe, feasible, and active in gastric cancer patients with malignant ascites, and is superior to other effector cell generation systems using DCs and epitope peptides. The adoptive immunotherapy of cancer using TRiDAK cells may be warranted in a clinical setting. This is the first study investigating anti-tumor effector cell generation using cultured DCs and tumor mRNA from gastric cancer cells.

Postoperative immunosuppression cascade and immunotherapy using lymphokine-activated killer cells for patients with esophageal cancer: possible application for compensatory anti-inflammatory response syndrome.

Immunological parameters were measured in order to elucidate a postoperative immunosuppression mechanism in transthoracic esophagectomy for patients with esophageal cancer. Moreover, lymphokine-activated killer (LAK) cells were transferred just after the surgery to overcome the postoperative immunosuppression. Fifteen consecutive patients who underwent transthoracic esophagectomy were subjected to the postoperative measurement of immunological parameters. Ten patients who underwent open cholecystectomy served as controls. Heparinized venous blood was obtained pre- and postoperatively, and serum levels of cytokines IL-6 and IL-10 and immunosuppressive acidic protein (IAP) were measured. Peripheral blood lymphocytes were harvested and analyzed by flow cytometry for phenotype detection and by a mixed lymphocyte reaction for detecting concanavalin (Con)-A-induced or -non-induced suppressor activity. Another 29 consecutive patients who underwent transthoracic esophagectomy were randomly enrolled in a postoperative immunotherapy trial either with or without lymphokine-activated killer cells. It was found that, in the esophagectomy group, IL-6 and IL-10 increased postoperatively and peaked on day 1, followed by an increase in IAP, peaked again on day 4, with a profound decrease in helper and cytotoxic T-cell subsets, followed by increases in Con-A-induced (on day 7 or later) and spontaneous (on day 10) suppressor activities. These changes were minimal in the cholecystectomy group. LAK cell transfer restored the postoperative decrease in the helper and cytotoxic T-cell population, and there was a trend of reduction for postoperative remote infection such as pneumonia and surgical site infection in the LAK therapy group. Taken together, we would like to propose the existence of a postoperative immunosuppression cascade consisting of increases in cytokines and immunosuppressive proteins, decreases in helper and cytotoxic T-cell populations, and the development of suppressor T-cell activities in surgery for esophageal cancer. Postoperative adoptive transfer of LAK cells may be a novel clinical application in surgery for esophageal cancer as a means of treating this postoperative immunosuppressive condition that may be identical to the status of compensatory anti-inflammatory response syndrome (CARS).

Generation of antigen-presenting cells using cultured dendritic cells and amplified autologous tumor mRNA.

Novel antigen-presenting cells (APCs) were generated using cultured dendritic cells (DCs) and amplified tumor mRNA, and the potential of tumor antigen-reactive T cell induction by the tumor RNA-introduced DCs (DC/tumor RNA) was analyzed in a patient with melanoma antigen-encoding gene (MAGE3)-positive malignant melanoma of the esophagus. DCs were generated from an adherent fraction of peripheral blood mononuclear cells in the presence of granulocyte macrophage colony-stimulating factor and interleukin-4. Tumor mRNA was purified from tumor tissue, amplified in vitro using a T7 RNA polymerase system, and then introduced into DCs by electroporation (150 V/150 microF or 100 V/200 microF). The gene introduction efficiency was 44-55% as measured by enhanced green fluorescent protein reporter gene expression, and the viability of RNA-introduced DCs was approximately 80%. DC/tumor RNA could induce tumor antigen-reactive cytotoxic T lymphocytes (CTLs) in an mRNA-specific manner, but had no effect on the self-antigen-reactive T cells. DC/tumor RNA could induce the polyspecific antigen-reactive CTL responses mediated by both human leukocyte antigen class I and class II molecules, whereas MAGE3 peptide-pulsed DCs induced only the monospecific MAGE3-reactive CTL responses mediated by human leukocyte antigen class I molecules, showing the superiority of the DC/tumor RNA over the DC/peptide. It is suggested that the use of DC/tumor RNA as antigen-presenting cells may be more effective, convenient and practical for the DC-based anti-cancer immunotherapy.

Neoadjuvant therapy of rectal cancer using oral tegaful-uracil (UFT) plus concomitant radiotherapy--a case report.

A 59-year-old male patient with rectal cancer 2 cm in diameter (T2) at the peritoneal reflection with suspicious left lateral node metastasis was treated with 400 mg of preoperative oral uracil and tegaful (UFT) for 5 weeks, 5 days a week in combination with concomitant radiotherapy of 45 Gy per 25 fractions for 5 weeks. After resting for another 5 weeks, colon fiberscopy, barium enema, and computed tomography revealed a trace of the primary tumor and a 40% shrinkage of the lateral metastasis. The serum CEA level decreased to the normal range during treatment. The adverse effects were nausea, bloody stool and elevation of transaminase, all at grade 1. Low anterior resection with a left hemi-lateral lymphadenectomy was performed through a suprapubic, one hand-size incision without laparoscopy. The preoperative treatment did not affect any operative procedures, and no postoperative complications occurred. The surgical specimen showed that the rectal tumor had been remarkably shrunk by the preoperative treatment, to the level of a superficial type tumor. Histological analysis indicated moderately differentiated adenocarcinoma cells that were present at only 2 mm in diameter in the mucosal layer, 6 mm in the submucosal layer, and 1 mm or less in the muscular layer with scar formation. No metastasis was detected in the 16 lymph nodes dissected, but an organizing tumor thrombus, which had preoperatively been diagnosed as lateral node metastasis, was detected. These results suggest that preoperative oral UFT plus concomitant radiotherapy may be a feasible, tolerable and effective treatment for patients with rectal cancer.

Feasibility study of adoptive immunotherapy for metastatic lung tumors using peptide-pulsed dendritic cell-activated killer (PDAK) cells.

We have established a novel culture system to generate effector lymphocytes designated as peptide-pulsed dendritic cell-activated killer (PDAK) cells using cultured dendritic cells (DCs), synthetic peptide, peripheral blood lymphocytes, and interleukin-2 plus immobilized anti-CD3 antibody. A feasibility study of an adoptive immunotherapy trial using PDAK cells was conducted on HLA-A2 and HLA-A24 cancer patients with antigen-positive lung metastasis that was defined by serological analysis or PCR analysis. Eleven patients with lung metastasis participated in the study: 6 with colorectal cancer, 2 with pancreatic cancer, 1 each with breast and lung cancer, and 1 with melanoma. The patients received either Muc-1, CEA, gpl00, Her-2 or SART-3-PDAK cells generated in vitro, intravenously in combination with 350,000 U IL-2 weekly for 9 weeks, together with a planned dose-escalation schedule of three transfers each of 1 x 10(7), 3 x 10(7) and 1 x 10(8) PDAK cells/kg for 6 patients, and with a uniform dose of 3 x 10(7) PDAK cells/kg for the remaining 5 patients. Peptide/HLA-specific cytotoxic activity and TCRVbeta gene usage of PDAK cells were analyzed. All transfers of PDAK cells, which showed peptide/HLA-specific lysis, were well-tolerated in all patients, and adverse effects (elevation of transaminase, fever, and headache) were observed primarily at grade 1, but in no case greater than grade 2. The generation of sufficient cells to treat the patients with 3 x 10(7) PDAK cells/kg was feasible using our culture system, but we were able to generate and administer the dose of 1 x 10(8) PDAK cells/kg in only one patient. One partial response (PR) of lung metastasis occurred in a pancreatic cancer patient who received 3 x 10(7) Muc-1-PDAK cells/kg. The cytolytic units of PDAK cells in this patient appeared to be substantially higher compared to those in PD patients. TCR gene usage analysis on PDAK cells revealed preferential usage of TCRVbeta segments. These results suggest that adoptive immunotherapy using PDAK cells for cancer patients with antigen-positive lung metastasis is safe and feasible, and tumor response should be examined in a future clinical trial

HER2-specific cytotoxic activity of lymphokine-activated killer cells in the presence of trastuzumab.

We investigated whether trastuzumab, a humanized anti-HER2 monoclonal antibody, could induce HER2-specific cytotoxic activity on lymphokine-activated killer (LAK) cells. Trastuzumab alone was not toxic to the HER2-positive breast cancer cell lines MDA-MB453 and ZR75-1, nor to the HER2-negative breast cancer cell lines MDA-MB468 and MCF-7. LAK cells, which were activated with 1000 U/ml IL-2 for 4 days (4-day LAK), showed cytotoxic activity against the MDA-MB453, ZR75-1 and MCF-7 cells, but not against MDA-MB468 cells. LAK cell cytotoxic activity against the HER2-positive breast cancer cell lines MDA-MB453 and ZR75-1 was significantly augmented in the presence of 10 nM trastuzumab, but that against the HER2-negative breast cancer cell lines MDA-MB468 and MCF-7 was not. The cytotoxic activity of LAK cells plus trastuzumab against the MDA-MB453 cells was significantly inhibited by the addition of cold MDA-MB453 cells or cold ZR75-1 cells, but not by addition of cold MDA-MB468 cells. Twenty-nine percent of the 4-day LAK cells were CD16+, and the cytotoxicity of LAK cells plus trastuzumab was abrogated with the anti-CD16 antibody treatment of the LAK cells in the cytotoxicity assay. Only 7% of the 10-day LAK cells were CD16+, and the 10-day LAK cells failed to exhibit cytotoxicity even with trastuzumab. These results suggest that HER2-specific cytotoxic activity, which is mediated by an antibody-dependent cellular cytotoxicity (ADCC) mechanism, can be induced on LAK cells by the addition of trastuzumab.

Enhancing effect of PS-K on IL-2-induced lymphocyte activation: possible involvement of antagonistic action against TGF-beta.

Effects of protein-bound polysaccharide (PS)-K on interleukin (IL)-2-induced responses of peripheral blood mononuclear cells (PBMCs) were studied. PS-K (50 mcg/ml) was observed to enhance proliferative responses, cytotoxic activities against K562 and Daudi target cells, CD25+ cell population and telomerase activity of PBMCs stimulated with IL-2. The cytotoxic effector cells could be generated in the presence of PS-K even with a minimum amount of IL-2. The enhancing effect of PS-K on the IL-2-induced lymphocyte activation was more evident in PBMCs from cancer patients than in those from healthy volunteers, suggesting that PS-K may be beneficial if combined in the IL-2-based immunotherapy of cancer. TGF-beta inhibited the IL-2-induced lymphocyte activation of proliferative responses, cytotoxic activities and CD25+ cell population, the inhibitions of which were abrogated with PS-K. PS-K also abrogated the TGF-beta-induced anchorage-independent growth of normal rat kidney cells. Flow cytometric analysis using a labeled TGF-beta revealed that PS-K blocked the binding of TGF-beta at its receptor level on the surface of PBMCs. It is suggested that PS-K enhances IL-2-induced lymphocyte activation through, in part, an antagonistic action against TGF-beta.

Host-oriented peptide evaluation using whole blood assay for generating antigen-specific cytotoxic T lymphocytes.

A whole blood assay using antigenic peptide was established to predict host cytotoxic T lymphocyte (CTL) precursor status. Blood samples from HLA-A24 donors and colorectal cancer patients were directly diluted with RPMI-1640 medium to a 20% blood concentration, then distributed to tubes and a peptide of an HLA-A24-restricted CEA peptide panel (20 microM) was added to the tubes. Incubation was performed for 4-5 days and supernatants were subjected to ELISA specific for IFN-gamma protein. It was observed that certain CEA peptides could stimulate the diluted blood samples to produce IFN-gamma. Only the peripheral blood mononuclear cells (PBMCs) that were purified from the IFN-gamma-positive samples of the whole blood assay showed positive spots, detected with IFN-gamma ELISPOT assay, and could proliferate with the stimulation of immobilized anti-CD3 antibody plus interleukin-2 (CD3/IL-2 system). The proliferating PBMCs expressed cytotoxic activity against HLA-A24+ CEA-expressing tumor cells and the TISI target cells pulsed with the CEA peptide that had been used to stimulate the PBMCs to produce IFN-gamma, but they did not kill the target cells pulsed with peptides that had failed to stimulate IFN-gamma production, nor did they kill the target cells alone. Theses findings suggest that the IFN-gamma production of the blood samples detected by the whole blood assay identifies the peptide that can induce the CEA antigen-specific CTL response. Detection of IFN-gamma gene expression using real-time-PCR analysis could identify the peptide within 6 hours, which is earlier than the protein analysis by ELISA. The whole blood assay using the CEA peptide panel for healthy donors and colorectal cancer patients revealed that IFN-gamma-inducible peptides were different among the individual samples tested, indicating that the CEA peptides that should be used for generating CTLs are different in individual patients. The whole blood assay using a CEA antigen peptide panel is simple and beneficial for identifying candidate peptides. The host-oriented peptide evaluation (HOPE) approach may provide hope for the augmentation of clinical efficacies for peptide-based cancer immunotherapy.

Locoregional immunotherapy of malignant ascites from gastric cancer using DTH-oriented doses of the streptococcal preparation OK-432: Treatment of Th1 dysfunction in the ascites microenvironment.

Locoregional administration of the streptococcal preparation OK-432 is effective in treating malignant ascites from gastric cancer. In order to enhance the efficacy, we conducted a pilot study of locoregional immunotherapy for malignant ascites using host-oriented doses of OK-432. Moreover, action mechanisms of OK-432 were further explored in view of the T-helper type 1 (Th1)-Th2 concept. Gastric cancer patients with cytologically determined malignant ascites were locoregionally administered with OK-432. The dose of OK-432 was selected according to the delayed-type hypersensitivity (DTH) reaction levels to OK-432. Cytokine production profiles of ascites cells were determined using whole ascites assay by stimulation with OK-432. IL-10 mRNA expression was analyzed using RT-PCR. It was found that a positive clinical response was observed in 37 of the 51 (73%) patients with the DTH-oriented approach, showing a significantly higher efficacy than traditional dosage methods using empirical doses (31/58, 53%) (p=0.0487). The DTH-oriented administration of OK-432 produced adverse effects such as fever elevation (p<0.0001) and abdominal pain (p=0.0013) to a significantly lesser extent compared with the traditional treatment. Analysis of the action mechanism of OK-432 revealed that the DTH reaction in responders (19+/-6 mm) was stronger than that in non-responders (6+/-4 mm) (p<0.0001). Tumor necrosis factor (TNF)-alpha production of ascites cells was also higher in responders (3943+/-1247 pg/ml) than in non-responders (1217+/-939 pg/ml) (p=0.0002). There was a significant positive correlation (p=0.0085) between the levels of DTH reaction and TNF-alpha production of ascites cells, but not of blood cells. Responders appeared to polarize on the Th1 axis when clinical responses were plotted on Th1-Th2 dimensions according to the cytokine production profiles of TNF-alpha, IFN-gamma, IL-4 and IL-6 of ascites cells. In vitro culture with IL-2 of ascites cells after OK-432 administration demonstrated an almost clonal expansion of CD4+ lymphocytes, which produced TNF-alpha and IFN-gamma, but did not produce IL-4 or IL-6. IL-10 mRNA expression was detectable in ascites cells from non-responders before treatment. These results suggest that the DTH-oriented locoregional administration of OK-432 may be both effective and less toxic in treating malignant ascites from gastric cancer, showing a possibility of the tailored immunotherapy for malignant ascites. Th1 dysfunction exists in the microenvironment of malignant ascites from gastric cancer, in which IL-10 may, in part, play a role. The up-regulation of Th1 responses by OK-432 may result in positive clinical responses. The DTH reaction to OK-432 may be a useful tool not only for predicting clinical response but also for selecting the optimal dose of OK-432.

[Generation of TRiDAK (tumor RNA-introduced dendritic cell-activated killer) cells].

Tumor-reactive effector lymphocytes were generated using tumor-derived amplified RNA and cultured dendritic cells (DC). Tumor RNAs were extracted from gastric cancer cell line MKN45 or cancer cells of malignant effusions, and were processed with T7 amplification. DCs were induced from an adherent cell population of peripheral blood mononuclear cells (PBMCs) with GM-CSF and IL-4. Tumor-RNA was introduced into DCs using electroporation. Effector cells were generated by stimulating a non-adherent fraction of PBMCs with tumor RNA-introduced DCs. It was observed that milligram RNA could efficiently be amplified from microgram RNA. The effector cells, designated as tumor-RNA-introduced DC-activated killer (TRiDAK) cells, showed IFN-gamma spots in a tumor-specific manner when examined using ELISPOT analysis, and demonstrated cytotoxic activities against tumor cells from which RNA was extracted. TRiDAK cells produced more tumor-specific IFN-gamma spots when stimulated repeatedly. These results suggest that TRiDAK cells are practical and may be effective lymphocytes for adoptive cancer immunotherapy.

[Tumor RNA introduction into dendritic cells and Epstein-Barr virus transformed B cells].

In induction of autologous tumor-reactive antigen (TRA) specific cytotoxic T lymphocytes (CTLs) using antigenic peptides and cultured dendritic cells (DCs), identification of the adequate tumor antigens and HLA typing of individuals are required. These restrictions have promoted the use of tumor cells themselves, including tumor cell lysates and tumor cell-DC fusion cells. However, it is very difficult to obtain enough tumor cells for treatment in the clinical setting. We have studied the use of RNA derived from tiny tumor cells. RNA was reverse-transcribed into cDNA, after which T7-amplification and in vitro transcription were carried out. The amplified RNA was successfully electroporated into DCs, and polyclonal polyspecific CTLs could be generated. EBV transformed B cells were also good candidates to be electroporated with the RNA. This suggests that tumor RNA amplification followed by introduction into DCs or EBV transformed B cells is a feasible and practical method to prepare potent APCs.

Adoptive immunotherapy of cancer using activated autologous lymphocytes--current status and new strategies.

After the discovery of interleukin-2 (IL-2), lymphokine-activated killer (LAK) cells, tumor-infiltrating lymphocytes (TILs), and cytotoxic T lymphocytes (CTLs) sensitized with the mixed lymphocyte-tumor culture (MLTC) system have been conducted in adoptive immunotherapy (AIT) trials during past 15 years. Although the overall response rate of tumor shrinkage was marginal (9%), locoregional administration of TILs for malignant effusions was effective (77%) for a decrease or disappearance of the effusions even in terminally-ill patients, resulting in an improvement of QOL. Recent advances for molecular understanding of antigen presentation and recognition have promoted us to enhance the efficacy of AIT by using cultured dendritic cells (DCs) for generating antigen-specific CTLs in vitro. The peptide-pulsed DC-activated killer (PDAK) cells showed tumor recognition against antigen-expressing cells, and were efficiently propagated with the IL2 plus immobilized anti-CD3 antibody (IL-2/CD3) culture system. Clinical trials using PDAK cells against patients with lung metastases are now progressed, in which peptides suitable for generating CTLs were chosen in individual patients using the method designated as host-oriented peptide evaluation (HPOE) approach. Moreover, DCs were introduced with tumor-derived RNA, which was amplified with the T7 promoter system, and then were used for stimulating lymphocytes. The tumor RNA-introduced DC-activated killer (TRiDAK) cells showed tumor-specific interferon-gamma spots even in a patient in whom we failed to generate PDAK cells using DCs and peptides, suggesting that the clinical trial of AIT using TRiDAK cells is warranted for the treatment of patients with metastatic cancer. Thus, more understanding of antigen-presentation and -recognition mechanisms and immune regulation systems may promote clinical applications of AIT to establish a novel modality of cancer treatment.