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There have been no systematic epidemiological evaluations of the relationship between thyroid autoimmunity and the clinical background of young patients with thyroid nodules. We aimed to clarify the clinical features associated with thyroglobulin or thyroperoxidase antibodies (thyroid autoantibodies [Tabs]) in children and young adults with nodules. We performed a cross-sectional study using data from 3,018 participants of 3–29 years of age with nodules, including thyroid cancer, from the Fukushima Health Management Survey. After stratification of the data for body mass index (BMI) and the bilateral width and thickness of the area (BWTAR) as indicators of thyroid volume for age, sex, body surface area (BSA), and sex-adjusted standard deviation score (SDS), trend analyses were performed. A logistic regression analysis was performed using tab-positivity as an objective variable. The overall prevalence of tab-positivity is 13.9%. It was high in females (17%), participants with diffuse goiter (DG) (19.2%), and those with papillary thyroid carcinoma (PTC) (12.8%). The age- and sex-adjusted odds ratios (95% confidence intervals) for BMI-SDS, BWTAR-SDS, presence of DG, diagnosis of PTC, and TSH concentrations were 0.962 (0.863–1.073), 1.263 (1.171–1.361), 7.357 (4.816–11.239), 2.787 (1.965–4.014), and 1.403 (1.257–1.564), respectively. Tab positivity was independently associated with a large thyroid, the presence of DG, the presence of PTC, and a high TSH concentration in patients with nodules. Based on the systematic epidemiologic evidence shown in young patients, Tab positivity might complement ultrasonography for the assessment of the thyroid function and identification of malignancy in younger patients with asymptomatic thyroid nodules.

Background & Aims: Hepatitis B virus (HBV)-DNA integration into the host genome contributes to hepatocellular carcinoma (HCC) development. KMT2B is the second most frequent locus of HBV-DNA integration in HCC; however, its role and function remain unclear. We aimed to clarify the impact of HBV-KMT2B integration in HCC development using a human genome-edited induced pluripotent stem cell (iPSCs) model. Methods: Based on the genetic information on HBV-KMT2B integration in HCC, we determined its complete DNA sequence and transcript variants. To exclude the effect of other oncogenic mutations, we reproduced HBV integration in healthy donor iPSCs with an intact genome and analyzed its effects using iPSC-derived hepatic progenitor cells (HPCs) and hepatocytes (iPS-Heps). Results: The reproduced HBV-KMT2B integration significantly upregulated the proliferation of hepatic cells. Comprehensive transcriptional and epigenetic analyses revealed enhanced expression of cell cycle-related genes in hepatic cells with HBV-KMT2B integration based on perturbation of histone 3 lysine 4 tri-methylation (H3K4me3), mimicking that in the original HCC sample. Long-read RNA-sequence detected the common KMT2B transcript variants in the HCC sample and HPCs. Overexpression of the truncated variant significantly enhanced proliferation of hepatic cells, whereas HBV-KMT2B fusion transcripts did not enhance proliferation. HBV-KMT2B-integrated HPCs exhibited replication stress and DNA damage, indicating that our model initiated the process of hepatocarcinogenesis due to abnormally promoted KMT2B function. Conclusions: Our disease model using genetically engineered iPSCs provides the first insight into both the KMT2B function in HCC development and the oncogenic processes by HBV-KMT2B integration. We clarified the novel oncogenic mechanism in HBV-related HCC due to aberrant KMT2B function.

Background: Adults with food-protein-induced enterocolitis syndrome (FPIES) often develop severe abdominal symptoms after eating seafood. However, no investigation of a food elimination strategy for adult FPIES patients has been performed to date. Methods: We conducted a retrospective cohort study of seafood–avoidant adults by telephone interview, based on the diagnostic criteria for adult FPIES reported by González et al. We compared the clinical profiles, abdominal symptoms, and causative seafoods between FPIES and immediate-type food allergy (IgE-mediated FA) patients. We also profiled the detailed intake-status of seafoods in adult FPIES patients. Results: Twenty-two (18.8 %) of 117 adults with seafood-allergy were diagnosed with FPIES. Compared with the IgE-mediated FA patients, FPIES patients had an older age of onset, more pre-existing gastrointestinal and atopic diseases, more episodes, longer latency and duration of symptoms, more nausea, abdominal distention, and severe abdominal pain, and more frequent vomiting and diarrhea. In particular, abdominal distention—reflecting intestinal edema and luminal fluid retention—may be the most distinctive characteristic symptom in adult FPIES (p

The main cause of diffuse thyroid goiter is autoimmune chronic thyroiditis, otherwise known as Hashimoto’s thyroiditis. Thyroid hormones play pivotal roles in growth and development during childhood. However, the prevalence of diffuse goiter and the relationships between diffuse goiter, thyroid volume, cysts and nodules, and anthropometric measurements in children are not well known. Among 789,459 participants who participated in thyroid ultrasound examinations, 320,206 participants (male: 161,728; female: 158,478) aged 1–23 years were analyzed. Logistic regression analyses were conducted to calculate the odds ratios of the standard deviation score of body mass index (BMI-SDS), the SDS of bilateral width multiplied thickness area (BWTAR-SDS) as a provisional determination of thyroid volume, and the presence of nodules or cysts for positive diffuse goiter compared with negative diffuse goiter after correction for sex and age. The prevalence of diffuse goiter increased in a female-dominant manner with aging. Compared with the absence of diffuse goiter, the age- and sex-adjusted odds ratios (95% confidence intervals) for BMI-SDS (1 SD), BWTAR-SDS (1 SD), cysts, and nodules were 1.24 (1.21–1.27), 3.21 (3.13–3.29), 0.53 (0.50–0.58), and 1.38 (1.17–1.64), respectively. The odds ratios of nodules for positive diffuse goiter were 4.18 (1.08–16.08), 1.76 (1.01–3.07), 1.80 (1.32–2.45), and 1.34 (1.08–1.67) in the age groups 1–7, 8–11, 12–15, and 16–23 years, respectively. The age-dependent increase in the prevalence of diffuse goiter was independently associated with increased BMI and positive prevalence of nodules in young individuals.

Background: Internal carotid artery stenosis is primarily attributed to atherosclerosis in the carotid artery bifurcation. Previous studies have detected oral bacteria in atherosclerotic lesions, suggesting an association between oral bacteria and atherosclerosis. In this study, we compared the bacterial flora of the atherosclerotic plaque in the carotid artery and dental plaque of patients with internal carotid artery stenosis using 16S ribosomal RNA (16S rRNA) metagenomic sequencing. Methods: Fifty-four patients who underwent internal carotid endarterectomy for internal carotid artery stenosis at the Showa University Hospital between April 2016 and February 2018 were included. Polymerase chain reaction targeting the 16S rRNA gene detected bacterial DNA in the carotid plaques of 11 cases, of which only 5 could be further analyzed. Thereafter, DNA extracted from the carotid and oral plaques of these 5 cases were analyzed using metagenomic sequencing targeting 16S rRNA. In addition, their general condition and oral conditions were evaluated. The patients were classified into symptomatic and asymptomatic groups based on the presence or absence of symptoms of transient ischemic attack, and their bacterial flora was evaluated. Results: The results demonstrated that the microflora of carotid plaques (n = 5) contained bacterial species from 55 families and 78 genera. In addition, 86.5% of the bacteria detected in the carotid plaques were also detected in oral plaques. Cariogenic and periodontopathic bacteria accounted for 27.7% and 4.7% of the bacteria in the carotid plaques, respectively. Conclusions: These results suggest that oral bacteria are directly or indirectly involved in the pathogenesis of atherosclerosis. More extensive studies of oral commensal bacteria detected in extra-oral lesions are warranted to comprehensively investigate the role of oral bacteria in the pathogenesis of systemic diseases.

Introduction Since May 2019, comprehensive genomic profiling (CGP) has been covered by Japan’s health insurance system for patients with solid tumours that have progressed on standard chemotherapy, rare tumours or tumours of unknown primary origin. Although CGP has the potential to identify actionable mutations that can guide the selection of genomically matched therapies for patients with advanced cancer and limited treatment options, less than 10% of patients benefit from CGP testing, which may have a negative impact on patients’ mental status. The aim of this study is to investigate the prevalence of psychological distress and associated factors among patients with advanced cancer who are undergoing CGP testing across Japan.Methods and analysis This multicentre, prospective cohort study will enrol a total of 700 patients with advanced cancer undergoing CGP testing. Participants will be asked to complete questionnaires at three timepoints: at the time of consenting to CGP testing (T1), at the time of receiving the CGP results (T2; 2–3 months after T1) and 4–5 months after T2 (T3). Primary outcome is the prevalence of depression as measured by the Patient Health Questionnaire-9 at the three timepoints. Secondary outcomes are the prevalence of anxiety and Quality of Life Score. Associated factors with psychological distress will also be examined, including knowledge about CGP, attitudes, values and preferences towards CGP, satisfaction with oncologists’ communication and patient characteristics as well as medical information including CGP test results and genomically matched therapies if provided. The prevalence of depression and anxiety will be estimated using the unadjusted raw rates observed in the total sample. Longitudinal changes in measures will be explored by calculating differences between the timepoints. Multivariate associations between variables will be examined using multiple or logistic regression analysis depending on the outcomes to adjust for confounders and to identify outcome predictors.Ethics and dissemination This study was approved by the Institutional Review Board of the National Cancer Center Japan on 5 January 2023 (ID: 2022-228). Study findings will be disseminated through peer-reviewed journals and conference presentations.Trial status The study is currently recruiting participants and the enrolment period will end on 31 March 2025, with an expected follow-up date of 31 March 2026.Trial registration number UMIN000049964.

Abstract The clinical symptoms of an immune checkpoint inhibitor (ICI)‐induced colitis are similar to those of ulcerative colitis. ICI‐induced colitis, like ulcerative colitis, may be complicated by other colitis, such as Clostridioides difficile infection (CDI). A 72‐year‐old man was admitted because of watery and bloody stools 10 times a day after three courses of nivolumab (antibodies against programmed death 1) and ipilimumab (cytotoxic T‐lymphocyte‐associated antigen‐4) for stage IV renal cell carcinoma. Colonoscopy revealed erythema and multiple erosions in the colon. Histopathological examination of colonic mucosa revealed diffuse inflammatory cell infiltration and apoptosis. The initial cytomegalovirus antigen test and C. difficile detection assay results were negative. Based on these findings, we diagnosed the patient with ICI‐induced colitis and discontinued ICI therapy. The symptoms did not improve despite the administration of Prednisolone and infliximab. A repeat colonoscopy revealed a new appearance of pseudomembranes from the sigmoid colon to the rectum one month after the start of these treatments. At this point, the patient tested positive for C. difficile. With treatment with vancomycin for CDI, the abdominal symptoms gradually decreased. Nivolumab alone was cautiously restarted. However, no colitis recurrence and further tumor reduction were observed. Here, we report our experience of a case of refractory ICI‐induced colitis complicated by CDI. ICI‐induced colitis may be complicated by CDI and should be carefully treated with repeated CDI testing if refractory to treatment. We believe that our observation will provide helpful information for determining an appropriate treatment strategy for ICI‐induced colitis.

We have previously reported that the expression of p53-binding protein 1 (53BP1) in nuclear foci (NF), a marker reflecting DNA damage response (DDR) , detected using immunofluorescence (IF) is useful to estimate the malignant pote ncy of diverse cancers. In this prospective study, we clarified the impact of 53BP1 express ion via IF as a biomarker to differentiate thyroid follicular tumors (FTs) with liquid-bas ed cytology (LBC). A total of 183 consecutively obtained-LBC samples, which were preoperatively suspected as FTs, were analyzed. Before histological diagnosis, the type of 53BP1 immunoreactivity in LBC was classified as follows: low DDR type, one or two NF; high DDR type, three or more NF; large foci type, larger than 1.0 μm; abnormal type, intense nuclear staining. Among the 183 cases, 136 cases were postoperatively diagnosed as FTs, including adenomatous goiter (AG, n = 30), follicular adenoma (FA, n = 60), FT-uncertain malignant potency (FT-UMP, n = 18), and follicular carcinoma (FC, n = 28), and 47 cases were diagnosed as tumors other than FTs or technically inadequate materials. Total 136 F T cases were collated with the type of 53BP1 immunoreactivity in LBC. The mean incidence e xpressing abnormal 53BP1 expression was significantly higher in FC than FA (9.5% vs 2.6%, P-value < 0.001). When adopting 4.3% as a cut-off value to distinguish FC from FA, the sensitivity, specificity, positive predictive value, and negative predictive value were 8 9.3, 83.3, 71.4, and 94.3%, respectively. Therefore, IF analysis of 53BP1 expression can be employed as a novel technique to diagnose FTs and to distinguish between different t ypes of FTs using LBC.

Acute duodenal perforation during endoscopic ultrasound (EUS) is a serious complication. The conventional endoscopic treatment for duodenal perforations such as endoscopic clipping is unsatisfactory; recently, the effectiveness of over-the-scope clipping (OTSC) has been reported. A 91-year-old woman was referred to our hospital with the chief complaint of jaundice. Contrast-enhanced computed tomography showed a 2-cm mass in the pancreatic head; we planned EUS-guided fine-needle aspiration. During exploration for a puncture route from the duodenal bulb using a linear echoendoscope under carbon dioxide insufflation, the duodenal lumen was suddenly filled with blood. A perforation

Abstract Background Young adult cancer patients often face unique challenges and have potential unmet needs. This study aimed (1) to describe unmet supportive care needs among young adults with cancer in Japan, and (2) to identify its associated factors. Methods In a cross-sectional web-based survey, 206 young adults with cancer were assessed for supportive care needs. Multiple regression analysis examined whether demographics, clinical variables and social support were associated with unmet supportive care needs. Results A total of 206 patients (180 female) with a mean age of 33.7 years (SD = 4.3, range: 22–39) participated. One hundred and fifty-eight participants (76.7%) reported at least one unmet supportive care needs. The top 20 unmet needs included 9 of the 10 psychological needs, 3 of the 5 physical and daily living needs, 8 of the 11 health system and information needs and 1 of the 5 sexuality needs. Multiple regression analysis revealed that perceived poorer PS, experience of change in work/school after a cancer diagnosis and poor social support were significantly associated with higher supportive care needs. The total score of supportive care needs was significantly associated with both psychological distress and QOL. Conclusions More than 70% of young adult cancer patients reported unmet supportive care needs and most of those were psychological needs. The findings suggest potential opportunities for intervention in addressing psychological needs rather than physical and information needs.

Formation of intrahepatic bile ducts (IHBDs) proceeds in accordance with their microenvironment. Particularly, mesenchymal cells around portal veins regulate the differentiation and ductular morphogenesis of cholangiocytes in the developing liver; however, further studies are needed to fully understand the arrangement of IHBDs into a continuous hierarchical network. This study aims to clarify the interaction between biliary and liver mesenchymal cells during IHBD formation. To identify candidate factors contributing to this cell–cell interaction, mesenchymal cells were isolated from embryonic day 16.5 matrix metalloproteinase 14 (MMP14)‐deficient (knockout [KO]) mice livers, in which IHBD formation is retarded, and compared with those of the wild type (WT). WT mesenchymal cells significantly facilitated the formation of luminal structures comprised of hepatoblast‐derived cholangiocytes (cholangiocytic cysts), whereas MMP14‐KO mesenchymal cells failed to promote cyst formation. Comprehensive analysis revealed that expression of vasoactive intestinal peptide (VIP) was significantly suppressed in MMP14‐KO mesenchymal cells. VIP and VIP receptor 1 (VIPR1) were mainly expressed in periportal mesenchymal cells and cholangiocytic progenitors during IHBD development, respectively, in vivo. VIP/VIPR1 signaling significantly encouraged cholangiocytic cyst formation and up‐regulated tight junction protein 1, cystic fibrosis transmembrane conductance regulator, and aquaporin 1, in vitro. VIP antagonist significantly suppressed the tight junction assembly and the up‐regulation of ion/water transporters during IHBD development in vivo. In a cholestatic injury model of adult mice, exogenous VIP administration promoted the restoration of damaged tight junctions in bile ducts and improved hyperbilirubinemia. Conclusion: VIP is produced by periportal mesenchymal cells during the perinatal stage. It supports bile duct development by establishing tight junctions and up‐regulating ion/water transporters in cholangiocytes. VIP contributes to prompt recovery from cholestatic damage through the establishment of tight junctions in the bile ducts.

Abstract Background Growth curves have been widely used in genetic analyses to gain insights into the growth characteristics of both animals and plants. However, several questions remain unanswered, including how the initial phenotypes affect growth and what is the duration of any such impact. For beef cattle production in Japan, calves are procured from farms that specialize in reproduction and then moved to other farms where they are fattened to achieve their market/purchase value. However, the causal effect of growth, while calves are on the reproductive farms, on their growth during fattening remains unclear. To investigate this, we developed a model that combines a structural equation with a growth curve model. The causal effect was modeled with B-splines, which allows inference of the effect as a curve. We fitted the proposed structural growth curve model to repeated measures of body weight from a Japanese beef cattle population (n = 3831) to estimate the curve of the causal effect of the calves’ initial weight on their trajectory of growth when they are on fattening farms. Results Maternal and reproduction farm effects explained 26% of the phenotypic variance of initial weight at fattening farms. The structural growth curve model was fitted to remove the effects of these factors in growth curve analysis at fattening farms. The estimated curve of causal effects remained at approximately 0.8 for 200 d after the calves entered the fattening farms, which means that 64% of the phenotypic variance was explained by the initial weight. Then, the effect decreased linearly and disappeared approximately 620 d after entering the fattening farms, which corresponded to an average age of 871.5 d. Conclusions The proposed model is expected to provide more accurate estimates of genetic values for growth patterns because the confounding causal factors such as maternal and reproduction farm effects are removed. Moreover, examination of the inferred curve of the causal effect enabled us to estimate the effect of a calf’s initial weight at arbitrary times during growth, which could provide suitable information for decision-making when shifting the time of slaughter, building models for genetic evaluation, and selecting calves for market.

Sporadic adenoma or adenocarcinoma is often detected during endoscopic surveillance of patients with ulcerative colitis (UC). However, it is occasionally difficult to distinguish these neoplasms from dysplasia or colitis-associated cancers because of the influence of inflammation. However, the influence of inflammation on sporadic neoplasms is not well characterised. To assess this influence, we established a long-term inflammation model of colon cancer cells by inflammatory stimulation with tumour necrosis factor-α, flagellin and interleukin-1β for 60 weeks. Then, the malignant phenotypes were evaluated using the MTS assay, Annexin V fluorescence assay, cell migration assay and sphere formation assay. The influence of P53 function on these phenotypes was assessed with a TP53 mutation model using the CRISPR/Cas9 system. A long-term inflammation model of LS174T cells was established for the first time with continuous inflammatory signalling. Chronic inflammation induced apoptosis and suppressed the proliferation and stemness of these cancer cells via the action of P53. It also enhanced the invasiveness of LS174T cells. Moreover, these phenotypic changes and changes in inflammatory signalling were recoverable after the removal of inflammatory stimuli, suggesting that colon cancer cells have higher plasticity than normal intestinal epithelial cells. In conclusion, our results suggest that sporadic neoplasms in patients with UC are affected by chronic inflammation but are not essentially altered.

Introduction Communication is an essential aspect of care for patients with progressive serious illnesses. This study aims to evaluate the efficacy of a new, integrated communication support program for oncologists, patients with rapidly progressing advanced cancer and their caregivers.Methods and analysis The proposed integrated communication support programme is in the randomised control trial stage. It comprises a cluster of oncologists from comprehensive cancer centre hospitals in a metropolitan area in Japan. A total of 20 oncologists, 200 patients with advanced pancreatic cancer and the patients’ caregivers are enrolled in this study as of the writing of this protocol report. Oncologists are randomly assigned to the intervention group (IG) or control group (CG). Patients and caregivers are allocated to the same group as their oncologists. The IG oncologists receive a 2.5-hour individual communication skills training, and patients and caregivers receive a half-hour coaching intervention to facilitate prioritising and discussing questions and concerns; the CG participants do not receive any training. Follow-up data will be collected quarterly for 6 months for a year and then annually for up to 3 years. The primary endpoint is the intergroup difference between before-intervention and after-intervention patient-centred communication behaviours during oncology visits.Ethics and dissemination This study is conducted in accordance with the ethical guidelines for clinical studies published by Japan’s Ministry of Education, Cultural, Sports, Science and Technology, the Ministry of Health, Labour and Welfare, and the ethical principles established for research on humans stipulated in the Declaration of Helsinki and further amendments thereto. The protocol was approved by the Institutional Review Board of National Cancer Center, Japan on 4 July 2018 (ID: 2017-474).Trial status This study is currently enrolling participants. Enrolment period ends 31 July 2020; estimated follow-up date is 31 March 2023.Trial registration number UMIN Clinical Trial Registry (UMIN000033612); pre-results.

Ribosomal RNA (rRNA), the most abundant non-coding RNA species, is a major component of the ribosome. Impaired ribosome biogenesis causes the dysfunction of protein synthesis and diseases called “ribosomopathies,” including genetic disorders with cancer risk. However, the potential role of rRNA gene (rDNA) alterations in cancer is unknown. We investigated germline and somatic single-nucleotide variants (SNVs) in the rDNA promoter region (positions −248 to +100, relative to the transcription start site) in 82 lung adenocarcinomas (LUAC). Twenty-nine tumors (35.4%) carried germline SNVs, and eight tumors (9.8%) harbored somatic SNVs. Interestingly, the presence of germline SNVs between positions +1 and +100 (n = 12; 14.6%) was associated with significantly shorter recurrence-free survival (RFS) and overall survival (OS) by univariate analysis (p < 0.05, respectively), and was an independent prognostic factor for RFS and OS by multivariate analysis. LUAC cell line PC9, carrying rDNA promoter SNV at position +49, showed significantly higher ribosome biogenesis than H1650 cells without SNV. Upon nucleolar stress induced by actinomycin D, PC9 retained significantly higher ribosome biogenesis than H1650. These results highlight the possible functional role of SNVs at specific sites of the rDNA promoter region in ribosome biogenesis, the progression of LUAC, and their potential prognostic value.

The initial step of bone regeneration requires the migration of osteogenic cells to defective sites. Our previous studies suggest that a salmon DNA-based scaffold can promote the bone regeneration of calvarial defects in rats. We speculate that the salmon DNA may possess osteoinductive properties, including the homing of migrating osteogenic cells. In the present study, we investigated the influence of the salmon DNA on osteoblastic differentiation and induction of osteoblast migration using MG63 cells (human preosteoblasts) in vitro. Moreover, we analyzed the bone regeneration of a critical-sized in vivo calvarial bone defect (CSD) model in rats. The salmon DNA enhanced both mRNA and protein expression of the osteogenesis-related factors, runt-related transcription factor 2 (Runx2), alkaline phosphatase, and osterix (OSX) in the MG63 cells, compared with the cultivation using osteogenic induction medium alone. From the histochemical and immunohistochemical assays using frozen sections of the bone defects from animals that were implanted with DNA disks, many cells were found to express aldehyde dehydrogenase 1, one of the markers for mesenchymal stem cells. In addition, OSX was observed in the replaced connective tissue of the bone defects. These findings indicate that the DNA induced the migration and accumulation of osteogenic cells to the regenerative tissue. Furthermore, an in vitro transwell migration assay showed that the addition of DNA enhanced an induction of osteoblast migration, compared with the medium alone. The implantation of the DNA disks promoted bone regeneration in the CSD of rats, compared with that of collagen disks. These results indicate that the salmon DNA enhanced osteoblastic differentiation and induction of migration, resulting in the facilitation of bone regeneration.

Background: Parvalbumin is the major and cross-reactive allergen in fish. Sufficient amounts of IgE-reactive recombinant fish parvalbumin are needed for diagnosis and immunotherapy of fish allergy. Methods: A DNA fragment corresponding to parvalbumin of the Pacific mackerel Scomber japonicus was synthesized and cloned into the expression vector pGEX-6p-3 to produce glutathione S-transferase (GST)-fusion parvalbumin in Escherichia coli. The GST-free recombinant parvalbumin was purified using the RediPack GST Purification Module (Amersham Pharmacia Biotech, Buckinghamshire, UK). Parvalbumins of seven species of fish (Japanese eel, horse mackerel, red sea bream, Pacific mackerel, skipjack, bigeye tuna and Japanese flounder) were purified by gel filtration and reverse-phase HPLC. The IgE-binding capacity was examined by ELISA and antigenic cross-reactivity by inhibition ELISA. Results: The GST-free recombinant Pacific mackerel parvalbumin was obtained in an electrophoretically pure state. Data from ELISA and inhibition ELISA revealed that the recombinant parvalbumin contains most of the IgE-binding epitopes of the natural counterpart. In addition, the recombinant parvalbumin inhibited the IgE reactivities of the pooled patient serum to parvalbumins purified from six species of fish in almost the same magnitude as the natural Pacific mackerel parvalbumin. Conclusions: Because the recombinant Pacific mackerel parvalbumin bearing the IgE-binding capacity of the natural counterpart is cross-reactive with various fish parvalbumins, it can be a useful tool for the diagnosis and immunotherapy of fish allergy.

Interaction of Fas and Fas ligand (FasL) plays an important role in the regulation of immune responses by inducing apoptosis of activated cells; however, a possible role of FasL in DNA vaccination has not been well understood. We examined whether administration of DNA encoding FasL gene enhanced antitumor effects in mice that were vaccinated with DNA expressing a putative tumor antigen gene, β-galactosidase (β-gal). Growth of β-gal-positive Colon 26 tumors was retarded in the syngeneic mice immunized with β-gal and FasL DNA compared with those vaccinated with β-gal or FasL DNA. We did not detect increased numbers of β-gal-specific CD8+ T cells in lymph node of mice that received combination of β-gal and FasL DNA, but amounts of anti-β-gal antibody increased with the combination but not with β-gal or FasL DNA injection alone. Subtype analysis of anti-β-gal antibody produced by the combination of β-gal and FasL DNA or β-gal DNA injection showed that IgG2a amounts were greater in mice injected with both DNA than those with β-gal DNA alone, but IgG2b amounts were lower in both DNA-injected than β-gal DNA-injected mice. These data suggest that FasL is involved in boosting humoral immunity against a gene product encoded by coinjected DNA and enhances the vaccination effects.

The effect of the synthetic extracellular matrix (ECM) in a diffusion chamber for a bioartificial endocrine pancreas (Bio-AEP) on pancreatic endocrine cells in vitro and its biocompatibility in dogs were investigated. Two different types of ECM were used: type I collagen treated with low antigen (type I LA), and reconstituted basement membrane matrix (Matrigel) derived from Englbreth-Holm-Swarm (EHS) mouse sarcoma. Matrigel contains growth and differentiation factors and cell adhesion molecules such as laminin, heparan sulfate proteoglycan, and entactin. Purified porcine pancreatic endocrine (PE) cells were suspended in type I LA or Matrigel and then placed into a 12-well culture plate (4 × 107 cells/ml · gel/well). The insulin accumulation from PE cells in Matrigel was significantly greater than that in type I LA (9.3 ± 3.6 mU/well vs. 2.3 ± 1.3 mU/well). When Bio-AEP with Matrigel and PE cells was implanted into the abdominal cavity of a pancreatectomized diabetic dog, the exogenous insulin requirement for maintaining normoglycemia was reduced for the first 4 weeks. However, after 6 weeks of implantation, fasting blood glucose levels suddenly increased. Laparotomy revealed encapsulated Bio-AEP with thick fibrous tissue. Following removal of the Bio-AEP from the abdominal cavity, another Bio-AEP containing type I LA and PE cells was implanted into the same dog. The exogenous insulin requirement was gradually decreased to almost half that of preim-plantation levels. Bio-AEPs containing type I LA or Matrigel, but not PE cells, were implanted into the abdominal cavities of four healthy dogs. After 4 weeks of implantation, the Bio-AEP with Matrigel was encapsulated with fibrous tissue similar to that in the diabetic dog, but the Bio-AEP with type I LA was not. These results indicate that Matrigel may be incompatible with dogs and that the type I LA is more suitable for Bio-AEP.