Dendritic cell vaccination in combination with erlotinib in a patient with inoperable lung adenocarcinoma: a case report.

BACKGROUND: Satisfactory treatment for patients with unresectable advanced lung cancer has not yet been established. We report a case of unresectable advanced lung cancer (stage IIIb: T2aN3M0) treated with a total of 15 doses of dendritic cells pulsed with a Wilms' tumor 1 and mucin 1 vaccine in combination with erlotinib, a small molecule epidermal growth factor receptor tyrosine kinase inhibitor, for more than 699 days without recurrence or metastasis. CASE PRESENTATION: A 63-year-old Korean woman was diagnosed with lung adenocarcinoma by pathology and computed tomography. The adenocarcinoma showed an epidermal growth factor receptor (EGFR) mutation, no anaplastic lymphoma kinase expression, and less than 1% expression of programmed death ligand 1. She received erlotinib alone for approximately 1 month. She then received erlotinib and the dendritic cells pulsed with Wilms' tumor 1 and mucin 1 vaccine. The diameter of the erythema at the vaccinated sites was 30 mm at 48 hours after the first vaccination. Moreover, it was maintained at more than 20 mm during the periods of vaccination. These results suggested the induction of antitumor immunity by the vaccine. Remarkably, the tumor size decreased significantly to 12 mm, a 65.7% reduction, after combined therapy with eight doses of the dendritic cells pulsed with Wilms' tumor 1 and mucin 1 vaccine and erlotinib for 237 days based on fluorodeoxyglucose uptake by positron emission tomography/computed tomography and computed tomography. Interestingly, after 321 days of combination therapy, the clinical findings improved, and no tumor was detected based on computed tomography. Validation of the tumor's disappearance persisted for at least 587 days after treatment initiation, without any indication of recurrence or metastasis. CONCLUSION: Standard anticancer therapy combined with the dendritic cells pulsed with Wilms' tumor 1 and mucin 1 vaccine may have therapeutic effects for such patients with unresectable lung adenocarcinoma.

Analysis of the NUDT15 gene and metabolites of azathioprine in Japanese patients with inflammatory bowel disease.

BACKGROUND: Thiopurines continue to play an important role in the treatment of inflammatory bowel disease (IBD). It is well known that thiopurines can cause several adverse reactions. Especially, hematopoietic toxicity may lead to severe agranulocytosis. In a previous prospective study, we investigated the relationship between inosine triphosphate pyrophosphatase (ITPA) c.94c > a polymorphism, 6-thioguanine nucleotide (6-TGN) concentration and toxicity. METHODS: To clarify the cause of thiopurine toxicity, we analysed nucleoside disphosphate-linked moiety X-type motif 15 (NUDT15) gene polymorphisms, i.e., R139C, V18I, and V19_V19insGV, and measured 6-mercaptopurines and 6-methylmercaptopurines (6-MMP) using the archived blood samples collected from 49 IBD patients for our previous study. RESULTS: The ITPA c.94c > a polymorphism was detected in 19 patients (38.7%, all heterozygous). The R139C polymorphism was found in 10 patients (20.4%, 1 homozygous, 9 heterozygous), V18_V19insGV in 7 patients (14.3%, all heterozygous), and V18I in 2 patients (4.08%, all heterozygous). Although R139C was more strongly associated with leukopenia than c.94c > a, there were no significant correlations with 6-TGN and 6-MMP levels, as for c.94c > a. The leukopenia incidence rates for each gene polymorphism were 0% in those with all wild-type genes, 21.4% for c.94c > a only, 42.9% for NUDT15 polymorphism (s) only, and 80.0% for both polymorphisms. CONCLUSIONS: All cases of leukopenia were associated with ITPA c.94c > a and/or polymorphism of NUDT15 and the risk of developing leukopenia was synergistically increased by ITPA and NUDT15 gene polymorphism. However, there was no association between the level of azathioprine metabolites and these polymorphisms.

Impact of Bifidobacterium adolescentis in patients with abdominal aortic aneurysm: a cross-sectional study.

The relationships between various diseases and the human gut microbiota (GM) have been revealed. However, the relationships between the human abdominal aortic aneurysm (AAA) and GM remains unknown. The aim of this cross-sectional study was to clarify the association between the human AAA and GM. Stool samples from 30 consecutive patients with AAA before aneurysm repair and those of 30 controls without vascular diseases were analyzed by 16S rRNA gene (V3-4) sequencing using an Illumina MiSeq system and QIIME 2. There was no significant difference in age (75 vs. 75 years) or gender (80% vs. 87% males) between the groups. No significant difference in GM composition was observed in principal coordinate analysis between the two groups, whereas the AAA group showed a significantly lower abundance of Bifidobacterium adolescentis (p<0.01) at the species level than the controls. This study demonstrated that the abundance of B. adolescentis decreased in patients with AAA. This is the first study to show the characteristics of the GM in patients with AAA. Studies are needed to reveal if causal relationships exists between the human AAA and GM.

Clinical features, therapeutic outcomes, and recovery period of long COVID.

To characterize the clinical features of long COVID, 286 patients who received care in our outpatient clinic for long COVID from May to December 2021 were surveyed. The recovery periods of each symptom and the key factors contributing to early recovery were statistically analysed. The median age of the patients was 35.8 years, with 137 men and 149 women. The median number of symptoms was 2.8. The most frequent symptoms were respiratory manifestations (52.1%), followed by fatigue (51.4%). Respiratory symptoms, fatigue, and headache/arthralgia were major complaints in the initial phase, whereas hair loss was a major complaint in the late phase, suggesting that the chief complaint of patients with long COVID may vary temporally. The best treatment outcome was observed for pulmonary symptoms, and hair loss had the worst outcome. COVID-19 severity, the number of manifestations, and the delay in starting treatment exerted a negative effect on the recovery period of long COVID. In addition, the smoking habit was an independent risk factor for slowing the recovery period from long COVID. This study provides insights into the clinical course of each manifestation and therapeutic options with a more certain future of long COVID to meet the unmet medical needs.

Usefulness of Bifidobacterium longum BB536 in Elderly Individuals With Chronic Constipation: A Randomized Controlled Trial.

INTRODUCTION: Few reports exist regarding the therapeutic effects of probiotics on chronic constipation in elderly individuals. This study evaluated the effects of Bifidobacterium longum BB536 in elderly individuals with chronic constipation. METHODS: This was a randomized, double-blind placebo-controlled, parallel-group superiority trial in Japan (UMIN 000033031). Eighty older adults diagnosed with chronic constipation were randomly assigned (1:1) to receive either probiotics ( B. longum BB536, 5 × 10 10 colony-forming unit, n = 39) or placebo (n = 41) once daily for up to 4 weeks. The severity of constipation was evaluated using the Constipation Scoring System. The primary end point was the difference in the changes from baseline in the constipation scoring system total score between the 2 groups at week 4. RESULTS: A total of 79 patients (mean age of 77.9 years), including 38 patients in the BB536 group and 41 in the placebo group, completed the study. The primary end point was not significant ( P = 0.074), although there was significant improvement ( P < 0.01) in the BB536 group from baseline to week 4, but there were no significant changes in the placebo group. There was a significant difference and a tendency toward a difference in the changes from baseline on the stool frequency ( P = 0.008) and failure of evacuation ( P = 0.051) subscales, respectively, at week 4 between the 2 groups. Few adverse events related to the probiotics were observed. DISCUSSION: The primary end points were not significant. However, probiotic supplementation significantly improved bowel movements. These results suggest that B. longum BB536 supplementation is safe and partially effective for improving chronic constipation in elderly individuals.

Dysbiosis of the Fecal and Biliary Microbiota in Biliary Tract Cancer.

Characteristic bile duct and gut microbiota have been identified in patients with chronic biliary tract disease. This study aimed to characterize the fecal and bile microbiota in biliary tract cancer (BTC) patients and their relationship. Patients with BTC (n = 30) and benign biliary disease (BBD) without cholangitis (n = 11) were included. Ten healthy, age-matched subjects were also recruited for fecal microbiota comparison. The fecal and bile duct microbiotas were analyzed by sequencing the 16S rRNA gene V3-V4 region. Live bacteria were obtained in the bile from three BTC patients by culture, and metagenomics-based identification was performed. Linear discriminant analysis effect size showed a higher Enterobacteriaceae abundance and a lower Clostridia abundance, including that of Faecalibacterium and Coprococcus, in the BTC patients than in the other subjects. Ten of 17 operational taxonomic units (OTUs) assigned to Enterobacteriaceae in the bile were matched with the OTUs found in the BTC subject fecal samples. Furthermore, a bile-isolated strain possessed the carcinogenic bacterial colipolyketide synthase-encoding gene. Enterobacteriaceae was enriched in the BTC feces, and more than half of Enterobacteriaceae in the bile matched that in the feces at the OTU level. Our data suggests that fecal microbiota dysbiosis may contribute to BTC onset.

The Detection of Immunity against WT1 and SMAD4P130L of EpCAM+ Cancer Cells in Malignant Pleural Effusion.

Malignant pleural effusion (MPE) provides a liquid tumor microenvironment model that includes cancer cells and immune cells. However, the characteristics of tumor antigen-specific CD8+ T cells have not been investigated in detail. Here, we analyzed MPE samples taken from a patient with pancreatic cancer who received a dendritic cell vaccine targeting Wilms' Tumor 1 (WT1) antigen over the disease course (two points at MPE1st and 2nd, two months after MPE1st). Epithelial cell adhesion molecule (EpCAM)+ cancer cells (PD-L1- or T cell immunoglobulin mucin-3, TIM-3-), both PD-1 or TIM-3 positive CD8+ T cells, and CD14+CD68+CD163+TIM-3+ macrophages increased from the MPE1st to MPE2nd. The ratio of WT1-specific cytotoxic lymphocytes (WT1-CTLs) to MPE CD8+ T cells and IFN-γ secretion of WT1-CTLs were reduced with disease progression. Coincidentally, the fraction of central memory T (TCM) of WT1-CTLs was decreased. On the other hand, CD8+ T cells in response to SMAD4P130L, which is homogeneously expressed in EpCAM+ cancer cells, were detected using in vitro expansion with the HLA-A*11:01 restrictive SVCVNLYH neoantigen. Furthermore, the CD8+ T cell response to SMAD4P130L was diminished following remarkably decreased numbers of CD8+ TCM in MPE samples. In conclusion, CD8+ T cells responding to WT1 or SMAD4P130L neoantigen expressed in EpCAM+ pancreatic cancer cells were detected in MPE. A tumor antigen-specific immune response would provide novel insight into the MPE microenvironment.

The insoluble excretion of multi-matrix system mesalazine preparations in patients with ulcerative colitis.

BACKGROUND: Multi-matrix mesalazine (MMX) is an important treatment for ulcerative colitis (UC); however, it is often excreted intact, which increases the risk of relapse. This study aimed to clarify the risk factors for insoluble MMX excretion. METHODS: The subjects were 102 UC patients who were newly prescribed MMX alone to induce remission. Their stools were evaluated on the Bristol Stool Form Scale (BSFS), the presence/absence of insoluble MMX excretion was investigated in interviews, and defecation frequency at the start of treatment and disease type were retrospectively investigated by examining their medical records. RESULTS: The insoluble excretion rate (IER) was 14.7%. It tended to be higher in the patients with left-sided colitis or extensive colitis, although the differences among the disease types were not significant (p = 0.053). The mean defecation frequency of the patients that reported insoluble MMX excretion was significantly higher than that of the patients that did not report it (6.27 ± 5.28 vs. 3.69 ± 3.17, p < 0.05). The IER tended to be higher among the patients with soft stools (4.5%, 21.9%, and 23.1% in those with BSFS scores of ≤ 4, 5, and ≥ 6, respectively). In ROC analysis of defecation frequency, ≥ 3.5 defecations was found to exhibit sensitivity and specificity of 66.7% and 65.5%, respectively, for predicting insoluble MMX excretion. CONCLUSIONS: The likelihood of insoluble MMX excretion is influenced by defecation frequency and the extent of inflammation. It is important to keep the possibility of insoluble excretion in mind when prescribing MMX.

Growth of various obligate and facultative anaerobic intestinal bacteria in cell culture medium under aerobic and anaerobic culture conditions.

Eight bacterial strains were used in this study to examine the survival of intestinal bacteria in immune cell cultures under aerobic and anaerobic culture conditions. With the addition of penicillin G and streptomycin, viable Clostridium clostridioforme and Fusobacterium varium cells did not decrease after 6 or 24 hr, even under aerobic conditions. Without antibiotics, eight bacterial strains did not decrease until 4 or 6 hr later, under both aerobic and anaerobic conditions. Escherichia coli numbers increased by more than 10 times under both conditions. In order to examine the effects of live gut bacteria on various immune cells, the viability of bacteria should be checked in cell culture media and under different conditions.

The stimulatory effect of fusobacteria on dendritic cells under aerobic or anaerobic conditions.

Fusobacteria have been suspected to be pathobionts of colon cancer and inflammatory bowel disease. However, the immunomodulatory properties that affect these inflammatory reactions in dendritic cells (DCs) under anaerobic and aerobic conditions have not yet been characterized. We directly assessed the stimulatory effects of anaerobic commensal bacteria, including fusobacteria, on a human DC line through coculture under aerobic or anaerobic conditions. Under aerobic or anaerobic conditions, stimulation of the DC line with all live commensal bacteria examined, except the probiotic Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus), significantly increased the geometric mean fluorescent intensity (MFI) of marker proteins (HLA-ABC, HLA-DR, CD80, CD86, CD83, or CCR7) on the DC surface. In particular, both Fusobacterium nucleatum (F. nucleatum) and Escherichia coli (E. coli) significantly increased the expression of DC-associated molecules, except for CD83 under both aerobic and anaerobic conditions. The DC line stimulated with Fusobacterium varium (F. varium) significantly increased only CD80, HLA-ABC, and HLA-DR expression under anaerobic conditions. Moreover, differences in the levels of proinflammatory cytokines, such as IL-6, IL-8, and TNF-α, were detected in the DC line stimulated by all live commensal bacteria under either aerobic or anaerobic conditions. Under aerobic conditions, the DC line stimulated with E. coli produced significantly more IL-6, IL-8, and TNF-α than did the cells stimulated with any of the bacteria examined. When E. coli were used to stimulate the DC line under anaerobic conditions, TNF-α was predominantly produced compared to stimulation with any other bacteria. Compared to the DC line stimulated with any other bacteria, the cells stimulated with F. nucleatum showed significantly increased production of IL-6, IL-8 and TNF-α only under anaerobic conditions. In particular, E. coli, F. nucleatum, and F. varium strongly stimulated the DC line, resulting in significantly increased expression of surface molecules associated with DCs and production of inflammatory cytokines.

Effect of Probiotic Bifidobacterium breve in Improving Cognitive Function and Preventing Brain Atrophy in Older Patients with Suspected Mild Cognitive Impairment: Results of a 24-Week Randomized, Double-Blind, Placebo-Controlled Trial.

BACKGROUND: Probiotics have been reported to ameliorate cognitive impairment. OBJECTIVE: We investigated the effect of the probiotic strain Bifidobacterium breve MCC1274 (A1) in enhancing cognition and preventing brain atrophy of older patients with mild cognitive impairment (MCI). METHODS: In this RCT, 130 patients aged from 65 to 88 years old with suspected MCI received once daily either probiotic (B. breve MCC1274, 2×1010 CFU) or placebo for 24 weeks. Cognitive functions were assessed by ADAS-Jcog and MMSE tests. Participants underwent MRI to determine brain atrophy changes using Voxel-based Specific Regional Analysis System for Alzheimer's disease (VSRAD). Fecal samples were collected for the analysis of gut microbiota composition. RESULTS: Analysis was performed on 115 participants as the full analysis set (probiotic 55, placebo 60). ADAS-Jcog subscale "orientation" was significantly improved compared to placebo at 24 weeks. MMSE subscales "orientation in time" and "writing" were significantly improved compared to placebo in the lower baseline MMSE (< 25) subgroup at 24 weeks. VSRAD scores worsened in the placebo group; probiotic supplementation tended to suppress the progression, in particular among those subjects with progressed brain atrophy (VOI Z-score ≥1.0). There were no marked changes in the overall composition of the gut microbiota by the probiotic supplementation. CONCLUSION: Improvement of cognitive function was observed on some subscales scores only likely due to the lower sensitiveness of these tests for MCI subjects. Probiotics consumption for 24 weeks suppressed brain atrophy progression, suggesting that B. breve MCC1274 helps prevent cognitive impairment of MCI subjects.

Impact of qualitative endoscopic ultrasonography on fatty pancreas at a referral medical center.

BACKGROUND: Taking advantage of the current advances in diagnostic imaging modalities, including endoscopic ultrasonography (EUS), and due to the increased attention to ectopic fat accumulation in the pancreas following the rising trend of metabolic syndrome, we qualitatively assessed the clinical implication of pancreatic steatosis by EUS in this study. METHODS: The study included 243 patients that were divided into four groups. The correlation between the average echogenicity of the pancreas and that of the control organs and the key clinical data of all study patients were collectively analyzed. The cut-off point of the pancreas-control (PC) ratio in EUS and liver-control (LC) ratio on abdominal ultrasound were determined from the population distribution and the obtained median values. RESULTS: With the cut-off point of 1.30 for the PC ratio and 1.20 for the LC ratio, sex, the Brinkman index, habitual alcohol drinkers, and fatty pancreas were significant factors. The associations between each relevant factor in fatty pancreas, metabolic syndrome in the fatty liver group, and age in the pancreatic cancer group were all significant in the analysis. In addition, we investigated whether the PC ratio differed according to age and staging in pancreatic cancer patients. Interestingly, the PC ratio was lower in the advanced stage group than in the early-stage group. CONCLUSION: Our results suggest that, irrespective of the degree, ectopic fat infiltration in the pancreas could be a specific clinical phenotype of serious pancreatic diseases, including pancreatic cancer, especially in high-risk patients.

Pancreatic tuberculosis in an immunocompetent young female mimicking a malignant tumor: A case report and diagnostic radiological investigation.

Tuberculosis remains the leading cause of infectious disease related death worldwide with extrapulmonary tuberculosis being particularly difficult to diagnose. Here, we report a case of pancreatic tuberculosis (PTB) in an immunocompetent young female, which mimicked a malignant tumor diagnosed by endoscopic ultrasound-guided fine needle aspiration and biopsy (EUS-FNAB). A 19-year-old Japanese female with no prior medical history presented with abdominal epigastralgia and appetite loss lasting 2 months. A solid lobular mass was observed in the pancreatic head with enhanced abdominal computed tomography and magnetic resonance imaging suggested it was a malignant pancreatic tumor. Using EUS-FNAB, granulomas with caseous necrosis and acid-fast bacilli were observed. Polymerase chain reaction results were positive for Mycobacterium tuberculosis but negative for Mycobacterium avium complex. Therefore, the patient was diagnosed with PTB. Her symptoms and radiological findings improved with a standard antituberculosis therapy. PTB is difficult to differentiate from other pancreatic diseases with Magnetic resonance imaging (MRI) patterns of T1, T2 weighted, or diffusion-weighted image (DWI) images. To investigate novel radiological diagnostics for PTB, we focused on MRI apparent diffusion coefficient (ADC) values, which have not been investigated in this context. The present case showed 0.52 × 10-3 mm2/s; additionally, the mean value of other mass-forming pancreatic diseases, such as pancreatic cancer was 1.592 × 10-3 mm2/s (the range: 1.015-3.025 × 10-3 mm2/s). The range does not overlap with the present PTB case or other pancreatic diseases. Therefore, ADC values may be useful as a noninvasive radiological diagnostic method for PTB.

Prognostic value of immune factors in the tumor microenvironment of patients with pancreatic ductal adenocarcinoma.

BACKGROUND: Both activated tumor-infiltrating lymphocytes (TILs) and immune-suppressive cells, such as regulatory T cells (Tregs), in the tumor microenvironment (TME) play an important role in the prognosis of patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: The densities of TILs, programmed death receptor 1 (PD-1) + T cells, and forkhead box P3 (Foxp3) + T cells were analyzed by immunohistochemical staining. The associations of the immunological status of the PDAC microenvironment with overall survival (OS) time and disease-free survival (DFS) time were evaluated. RESULTS: PDAC patients with a high density of TILs in the TME or PD-1-positive T cells in tertiary lymphoid aggregates (TLAs) demonstrated a significantly better prognosis than those with a low density of TILs or PD-1-negativity, respectively. Moreover, PDAC patients with high levels of Foxp3-expressing T cells showed a worse prognosis than those with low levels of Foxp3-expressing T cells. Importantly, even with a high density of the TILs in TME or PD-1-positive T cells in TLAs, PDAC patients with high levels of Foxp3-expressing T cells showed a worse prognosis than patients with low levels of Foxp3-expressing T cells. A PDAC TME with a high density of TILs/high PD-1 positivity/low Foxp3 expression was an independent predictive marker associated with superior prognosis. CONCLUSION: Combined assessment of TILs, PD-1+ cells, and Foxp3+ T cells in the TME may predict the prognosis of PDAC patients following surgical resection.

Long-term outcomes of antibiotic combination therapy for ulcerative colitis.

AIMS: An antibiotic combination of amoxicillin, tetracycline and metronidazole (ATM) is effective for ulcerative colitis (UC), but this regimen is discontinued in some cases due to adverse events. This study aimed to assess a revised combination, namely, amoxicillin, fosfomycin and metronidazole (AFM), in UC patients with the goal of reducing side effects while maintaining therapeutic efficacy. METHODS: A prospective open-label trial was undertaken in 104 adult UC patients. A combination of oral amoxicillin (1500 mg), fosfomycin (3000 mg) and metronidazole (750 mg) was administered to patients daily for 2-4 weeks in addition to their conventional medication. Clinical assessment was performed using the Lichtiger index before treatment and at 0, 3, 6, 9 and 12 months and 2 and 3 years. Endoscopic evaluation was performed using the Mayo score before treatment and at 3 and 12 months. RESULTS: The compliance rate was 99.2%. Response and remission rates were 80.8% and 63.5% at completion, 73.1% and 64.4% at 3 months, and 39.4% for both at 12 months, respectively. Of the 41 patients who were in remission at 12 months, 63.4% maintained that status until the 2-year follow-up. Similarly, 69.2% of those in remission at 2 years remained relapse free at the 3-year follow-up. Side effects were observed in 44.2% of the participants. Fever occurred in one patient (1.0%), which was lower than the rate observed with ATM therapy. CONCLUSION: These results indicate that AFM therapy induces remission and is appropriate for long-term maintenance of UC while producing fewer and milder adverse events than ATM therapy. CLINICAL TRIALS: This study was registered in the University Hospital Medical Information Network (No. R000046546).

Cancerous pericarditis presenting as cardiac tamponade in a 68-year-old man with pancreatic adenocarcinoma: a case report.

INTRODUCTION: Pericardial effusion is a rare complication of pancreatic cancer. We report a case of cardiac tamponade secondary to pancreatic cancer. CASE PRESENTATION: A 68-year-old Japanese man was diagnosed as having pancreatic cancer during surgery and received chemotherapy for 28 months after the diagnosis. He was admitted to the emergency room with severe dyspnea. Echocardiography revealed pericardial effusion with severe hypofunction. Emergency pericardial drainage was performed to maintain hemodynamics, which resulted in the elimination of 450 mL of blood and the maintenance of circulatory dynamics. Cytological examination of the pericardial fluid revealed atypical cells and tumor cells suggesting adenocarcinoma. CONCLUSIONS: To our knowledge, pancreatic cancer complicated with cancerous pericarditis has not been previously documented. This case highlights the extreme severity of pericardial effusion, a sign of progressive disease, secondary to pancreatic cancer. In the case of neoplastic pericardial effusion, an extremely poor prognosis must be considered.

Impact of mature dendritic cells pulsed with a novel WT1 helper peptide on the induction of HLA­A2­restricted WT1­reactive CD8+ T cells.

The proliferation and activation of CD4+ T helper 1 (Th1) cells and CD8+ cytotoxic T lymphocytes (CTLs) that produce interferon­Î³ (IFN­Î³) is an essential action of effective cancer vaccines. Recently, a novel Wilms' tumor 1 (WT1) helper peptide (WT1 HP34­51; amino acid sequence, WAPVLDFAPPGASAYGSL) applicable for various human leukocyte antigen (HLA) subtypes (HLA­DR, HLA­DP and HLA­DQ) was reported to increase peptide immunogenicity; however, the function of WT1 HP34­51 remains unclear. In the present study, mature dendritic cells (mDCs) pulsed with WT1 HP34­51 (mDC/WT1 HP34­51) activated not only WT1­specific CD4+ T cells but also CD8+ T cells that produced IFN­Î³ following stimulation with immature dendritic cells (imDCs) pulsed with WT1 killer peptide (imDC/WT1 KP37­45) in an HLA­A*02:01­ or HLA­A*02:06­restricted manner. Furthermore, the activated WT1­reactive CD4+ Th1 cells were predominantly effector memory (EM) T cells. In 5 of 12 (41.7%) patients with cancer carrying the HLA­A*02:01 or HLA­A*02:06 allele, WT1­reactive CD8+ T cells stimulated with mDC/WT1 HP34­51 enhanced their levels of WT1 KP37­45­specific IFN­Î³ production, with an increase >10%. Simultaneous activation of CD4+ and CD8+ T cells occurred more often when stimulation with mDC/WT1 HP34­51 was combined with imDC/WT1 KP37­45 restimulation. These results indicated that the novel mDC/WT1 HP34­51 combination induced responses by WT1­specific EM CD4+ Th1 cells and HLA­A*02:01­ or HLA­A*02:06­restricted CD8+ CTLs, suggesting its potential as a WT1­targeting cancer vaccine.

Dendritic Cells Pre-Pulsed with Wilms' Tumor 1 in Optimized Culture for Cancer Vaccination.

With recent advances in cancer vaccination therapy targeting tumor-associated antigens (TAAs), dendritic cells (DCs) are considered to play a central role as a cell-based drug delivery system in the bioactive immune environment. Ex vivo generation of monocyte-derived DCs has been conventionally applied in adherent manufacturing systems with separate loading of TAAs before clinical use. We developed DCs pre-pulsed with Wilms' tumor (WT1) peptides in low-adhesion culture maturation (WT1-DCs). Quality tests (viability, phenotype, and functions) of WT1-DCs were performed for process validation, and findings were compared with those for conventional DCs (cDCs). In comparative analyses, WT1-DCs showed an increase in viability and recovery of the DC/monocyte ratio, displaying lower levels of IL-10 (an immune suppressive cytokine) and a similar antigen-presenting ability in an in vitro cytotoxic T lymphocytes (CTLs) assay with cytomegalovirus, despite lower levels of CD80 and PD-L2. A clinical study revealed that WT1-specific CTLs (WT1-CTLs) were detected upon using the WT1-DCs vaccine in patients with cancer. A DC vaccine containing TAAs produced under an optimized manufacturing protocol is a potentially promising cell-based drug delivery system to induce acquired immunity.

In Vivo Administration of Recombinant Human Granulocyte Colony-Stimulating Factor Increases the Immune Effectiveness of Dendritic Cell-Based Cancer Vaccination.

Significant recent advances in cancer immunotherapeutics include the vaccination of cancer patients with tumor antigen-associated peptide-pulsed dendritic cells (DCs). DC vaccines with homogeneous, mature, and functional activities are required to achieve effective acquired immunity; however, the yield of autologous monocyte-derived DCs varies in each patient. Priming with a low dose of recombinant human granulocyte colony-stimulating factor (rhG-CSF) 16-18 h prior to apheresis resulted in 50% more harvested monocytes, with a significant increase in the ratio of CD11c+CD80+ DCs/apheresed monocytes. The detection of antigen-specific cytotoxic T lymphocytes after Wilms' tumor 1-pulsed DC vaccination was higher in patients treated with rhG-CSF than those who were not, based on immune monitoring using tetramer analysis. Our study is the first to report that DC vaccines for cancer immunotherapy primed with low-dose rhG-CSF are expected to achieve higher acquired immunogenicity.