Pancreatic Lymph Nodes Research Articles

Insights From Single Cell RNA Sequencing Into the Immunology of Type 1 Diabetes- Cell Phenotypes and Antigen Specificity.

In the past few years, huge advances have been made in techniques to analyse cells at an individual level using RNA sequencing, and many of these have precipitated exciting discoveries in the immunology of type 1 diabetes (T1D). This review will cover the first papers to use scRNAseq to characterise human lymphocyte phenotypes in T1D in the peripheral blood, pancreatic lymph nodes and islets. These have revealed specific genes such as IL-32 that are differentially expressed in islet –specific T cells in T1D. scRNAseq has also revealed wider gene expression patterns that are involved in T1D and can predict its development even predating autoantibody production. Single cell sequencing of TCRs has revealed V genes and CDR3 motifs that are commonly used to target islet autoantigens, although truly public TCRs remain elusive. Little is known about BCR repertoires in T1D, but scRNAseq approaches have revealed that insulin binding BCRs commonly use specific J genes, share motifs between donors and frequently demonstrate poly-reactivity. This review will also summarise new developments in scRNAseq technology, the insights they have given into other diseases and how they could be leveraged to advance research in the type 1 diabetes field to identify novel biomarkers and targets for immunotherapy.

S2623 Chronic Lymphoid Leukemia With Extensive Liver Infiltration in the Absence of Leukemic Transformation

Introduction: Chronic lymphoid leukemia (CLL) is the most common hematologic cancer diagnosed in the elderly. Its association with liver dysfunction secondary to leukemic infiltration ranges from mild elevations in liver enzymes (LE) to acute liver failure. Severe hepatic infiltration is typically associated with acute leukemic transformation. Here we report an atypical manifestation of CLL with rising LE and white blood cell (WBC) count mimicking leukemic transformation. Case Description/Methods: 62-year-old male with history of CLL not on therapy presented to clinic for abnormal LE and rising leukocytosis. Patient reported fatigued, jaundice, right upper quadrant pain and 25lb weight loss over five months attributed to dietary modifications. Patient reported taking glimepiride, atorvastatin and herbal supplements (GNC50+ multivitamin, fertility and prostate multivitamin) that were stopped five months prior to encounter due to concerns of drug-induced liver injury (DILI). Labs were significant for absolute lymphocytosis >53,000/uL, AST 156U/L, ALT 336U/L, total bilirubin 4.4 mg/dl, direct bilirubin 3.57mg/dl and gamma-glutamyl transferase of 94U/L from previously normal LE. Additional work up was negative for viral and autoimmune etiologies. NASH Fibrosure was consistent with F4 Fibrosis. Computer tomography (CT) of abdomen did not demonstrate fatty changes but did show significant abdominal lymphadenopathy. Patient was hospitalized for rapidly rising WBC and LE. Abdominal ultrasound doppler showed patent liver vasculature. Transjugular liver biopsy was negative for acute leukemic transformation, but did identify extensive, >60% sinusoidal infiltration by CLL with hepatic venous pressure gradient (HVPG) of 11 mmHG attributed to periportal and peripancreatic adenopathy observed on CT imaging (Imaging A-D). Patient was initiated on Venetoclax and Obinutuzumab as an outpatient. LE peaked two months after chemotherapy initiation. Liver synthetic function remained normal (Table 1). Discussion: After ruling out DILI with failed improvement upon discontinuation of suspected agents and liver biopsy, extensive CLL extranodal liver involvement was attributed to have caused liver dysfunction and subsequent portal hypertension. Severe pattern of involvement is rare without Richter Transformation, which can be seen in 8% of CLL patients. Due to severe pattern of liver infiltration, worsening LE, portal hypertension, and hepatosplenomegaly it was ultimately decided to start patient on chemotherapy.Figure 1.: Image A:CT abdomen and pelvis with IV contrast depicting an enlarged 33.4x42.9mm periportal lymph node Image B: CT abdomen and pelvis with IV contrast depicting 11.7x18.3mm pancreatic lymph node Image C: : H&E (400x) section demonstrates an atypical lymphoid follicle surrounding bile ductules, with adjacent liver parenchyma. Characteristic immunohistochemical staining of the neoplastic cells shows positivity for CD20 (dim), CD5, CD23, and is negative for CD3 Image D: ZAP 70 (400x) staining (brown) of neoplastic cells has been associated with a poor prognosis.Table 1.: Patient laboratory information from date of diagnosis to most recent outpatient follow up. Footnote: *Represents laboratory data for time of hospital admission for elevated liver enzyme work up **Represents the laboratory data prior to initiation of chemotherapy ***Represents peak liver enzyme abnormality ****Represents most recent outpatient follow up laboratory data.

Coreceptor therapy has distinct short- and long-term tolerogenic effects intrinsic to autoreactive effector T cells.

Immunotherapies are needed in the clinic that effectively suppress β cell autoimmunity and reestablish long-term self-tolerance in type 1 diabetes. We previously demonstrated that nondepleting anti-CD4 (αCD4) and αCD8α antibodies establish rapid and indefinite remission in recent-onset diabetic NOD mice. Diabetes reversal by coreceptor therapy (CoRT) is induced by suppression of pathogenic effector T cells (Teffs) and the selective egress of T cells from the pancreatic lymph nodes and islets that remain free of infiltration in the long term. Here, we defined CoRT-induced events regulating early Teff function and pancreatic residency, and long-term tolerance. TCR-driven gene expression controlling autoreactive Teff expansion and proinflammatory activity was suppressed by CoRT, and islet T cell egress was dependent on sphingosine-1 phosphate. In both murine and human T cells, CoRT upregulated the Foxo1 transcriptional axis, which in turn was required for suppression and efficient pancreatic egress of Teffs. Interestingly, long-term tolerance induced in late-preclinical NOD mice was marked by reseeding of the pancreas by a reduced CD8+ Teff pool exhibiting an exhausted phenotype. Notably, PD-1 blockade, which rescues exhausted Teffs, resulted in diabetes onset in protected animals. These findings demonstrate that CoRT has distinct intrinsic effects on Teffs that impact events early in induction and later in maintenance of self-tolerance.

EUS-Guided Biopsy with a Novel Puncture Biopsy Forceps Needle—Feasibility Study

Endoscopic ultrasound (EUS) with fine needle aspiration (FNA) or biopsy (FNB) to diagnose lesions in the gastrointestinal tract is common. Demand for histology sampling to identify treatment-specific targets is increasing. Various core biopsy FNB needles to obtain tissue for histology are currently available, however, with variable (37–97%) histology yields. In this multicenter study, we evaluated performance, safety, and user experience of a novel device (the puncture biopsy forceps (PBF) needle). Twenty-four procedures with the PBF needle were performed in 24 patients with a suspected pancreatic lesion (n = 10), subepithelial lesion (n = 10), lymph node (n = 3), or pararectal mass (n = 1). In 20/24 (83%) procedures, the PBF needle yielded sufficient material for interpretation (sample adequacy). In 17/24 (71%), a correct diagnosis was made with the material from the PBF needle (diagnostic accuracy). All participating endoscopists experienced a learning curve. (Per)procedural technical issues occurred in four cases (17%), but there were no adverse events. The PBF needle is a safe and potentially useful device to obtain an EUS-guided biopsy specimen. As the design of the PBF needle is different to core biopsy FNB needles, specific training will likely further improve the performance of the PBF needle. Furthermore, the design of the needle needs further improvement to make it more robust in clinical practice.

Recent Advances in Endosonography-Elastography: Literature Review.

Ultrasonographic elastography is a modality used to visualize the elastic properties of tissues. Technological advances in ultrasound equipment have supported the evaluation of elastography (EG) in endosonography (EUS). Currently, the usefulness of not only EUS-strain elastography (EUS-SE) but also EUS-shear wave elastography (EUS-SWE) has been reported. We reviewed the literature on the usefulness of EUS-EG for various diseases such as chronic pancreatitis, pancreatic solid lesion, autoimmune pancreatitis, lymph node, and gastrointestinal and subepithelial lesions. The importance of this new diagnostic parameter, “tissue elasticity” in clinical practice might be applied not only to the diagnosis of liver fibrosis but also to the elucidation of the pathogeneses of various gastrointestinal diseases, including pancreatic diseases, and to the evaluation of therapeutic effects. The most important feature of EUS-EG is that it is a non-invasive modality. This is an advantage not found in EUS-guided fine needle aspiration (EUS-FNA), which has made remarkable progress in the field of diagnostics in recent years. Further development of artificial intelligence (AI) is expected to improve the diagnostic performance of EUS-EG. Future research on EUS-EG is anticipated.

Oral probiotic promotes indoleamine 2,3-dioxygenase- and TGF-β–Producing plasmacytoid dendritic cells to initiate protection against type 1 diabetes

Colonization factor antigen I (CFA/I) fimbria, an adhesin from enterotoxigenic Escherichia coli, confers protection in murine autoimmune models for type 1 diabetes (T1D), multiple sclerosis, and rheumatoid arthritis. Although CFA/I fimbriae's initial mode of action is in a bystander or in an antigen (Ag)-independent fashion, protection is ultimately dependent upon the induction and/or activation of auto-Ag-specific regulatory T cells (Tregs). However, little is known about how protection transitions from bystander suppression to Ag-specific Tregs. Since dendritic cells (DCs) play an integral role in fate decisions for T cells becoming inflammatory or tolerogenic, the described study tests the hypothesis that Lactococcus lactis expressing CFA/I (LL-CFA/I) stimulates DCs to establish a regulatory microenvironment. To this end, bone marrow-derived dendritic cells (BMDCs) were infected in vitro with LL-CFA/I. Results revealed increased production of IL-10, TGF-β, and indoleamine 2,3-deoxygenase (IDO). Although co-culture of LL-CFA/I infected BMDCs with naïve T cells did not promote Foxp3 expression, TNF-α and IFN-γ production was suppressed. NOD mice orally dosed with LL-CFA/I showed an increase in regulatory plasmacytoid DCs (pDCs) expressing IDO and TGF-β in pancreatic lymph nodes (PaLNs) and spleen three days post-treatment. However, Tregs did not appear in the mucosal inductive sites until much later. These findings show that LL-CFA/I influences specific DC populations to establish tolerance.

Endoscopic ultrasound fine needle aspiration vs fine needle biopsy for pancreatic masses, subepithelial lesions, and lymph nodes.

Endoscopic ultrasound tissue acquisition, in the form of both fine needle aspiration (EUS-FNA) and fine needle biopsy (EUS-FNB), is utilized for pancreatic mass lesions, subepithelial lesions, and lymph node biopsy. Both procedures are safe and yield high diagnostic value. Despite its high diagnostic yield, EUS-FNA has potential limitations associated with cytological aspirations, including inability to determine histologic architecture, and a small quantitative sample for further immunohistochemical staining. EUS-FNB, with its larger core biopsy needle, was designed to overcome these potential limitations. However, it remains unclear which technique should be used and for which lesions. Comparative trials are plagued by heterogeneity at every stage of comparison; including variable needles used, and different definitions of endpoints, which therefore limit generalizability. Thus, we present a review of prospective trials, systematic reviews, and meta-analyses on studies examining EUS-FNA vs EUS-FNB. Prospective comparative trials of EUS-FNA vs EUS-FNB primarily focus on pancreatic mass lesions, and yield conflicting results in terms of demonstrating the superiority of one method. However, consistent among trials is the potential for diagnosis with fewer passes, and a larger quantity of sample achieved for next generation sequencing. With regard to subepithelial lesions and lymph node biopsy, fewer prospective trials exist, and larger prospective studies are necessary. Based on the available literature, we would recommend EUS-FNB for peri-hepatic lymph nodes.

Pharmacokinetics of preoperative intraperitoneal 5-FU in patients with pancreatic ductal adenocarcinoma

PurposeThe aim was to investigate the pharmacokinetics of preoperatively administered intraperitoneal (IP) 5-FU in patients with resectable pancreatic ductal adenocarcinoma (PDAC) by analyzing levels of 5-FU and target metabolites in peritoneal fluid, plasma, liver, lymph nodes, pancreatic tumour, and pancreatic tissue. These results were correlated to expression of genes encoding enzymes of the 5-FU pathway and cell membrane transporters of 5-FU and FdUMP.MethodsTwenty-two patients with PDAC were treated with IP 5-FU before surgery. The postoperative treatment followed a routine clinical protocol. 5-FU and its metabolites were analyzed by LC–MS/MS. The expression of genes encoding enzymes and transporters in the 5-FU pathway was analyzed by qPCR.ResultsAfter IP treatment, 5-FU could be detected in plasma, lymph nodes, liver, pancreatic tumour, and pancreatic tissue. The highest 5-FU concentration was found in the liver, also expressing high levels of the 5-FU transporter OAT2. 5-FU was converted to active FdUMP in all tissues and the highest concentration was measured in lymph nodes, liver and pancreatic tumour (18.5, 6.1 and 6.7 pmol/g, respectively). There was a correlation between the FdUMP and dUr levels in lymph nodes (r = 0.70, p = 0.0076). In tumours, there was an association between OAT2 expression and FdUMP concentration.ConclusionThe study shows uptake of IP 5-FU and drug metabolism to active FdUMP in pancreatic tumour, liver, and lymph nodes. Extended studies are warranted to evaluate the IP route for 5-FU administration in PDAC patients.

Function, Failure, and the Future Potential of Tregs in Type 1 Diabetes

Critical insights into the etiology of type 1 diabetes (T1D) came from genome-wide association studies that unequivocally connected genetic susceptibility to immune cell function. At the top of the susceptibility are genes involved in regulatory T-cell (Treg) function and development. The advances in epigenetic and transcriptional analyses have provided increasing evidence for Treg dysfunction in T1D. These are well supported by functional studies in mouse models and analysis of peripheral blood during T1D. For these reasons, Treg-based therapies are at the forefront of research and development and have a tangible probability to deliver a long-sought-after successful immune-targeted treatment for T1D. The current challenge in the field is whether we can directly assess Treg function at the tissue site or make informative interpretations based on peripheral data. Future studies focused on Treg function in pancreatic lymph nodes and pancreas could provide key insight into the ultimate mechanisms underlying Treg failure in T1D. In this Perspective we will provide an overview of current literature regarding Treg development and function in T1D and how this knowledge has been applied to Treg therapies.

Arrest in the Progression of Type 1 Diabetes at the Mid-Stage of Insulitic Autoimmunity Using an Autoantigen-Decorated All-trans Retinoic Acid and Transforming Growth Factor Beta-1 Single Microparticle Formulation.

Type 1 diabetes (T1D) is a disorder of impaired glucoregulation due to lymphocyte-driven pancreatic autoimmunity. Mobilizing dendritic cells (DC) in vivo to acquire tolerogenic activity is an attractive therapeutic approach as it results in multiple and overlapping immunosuppressive mechanisms. Delivery of agents that can achieve this, in the form of micro/nanoparticles, has successfully prevented a number of autoimmune conditions in vivo. Most of these formulations, however, do not establish multiple layers of immunoregulation. all-trans retinoic acid (RA) together with transforming growth factor beta 1 (TGFβ1), in contrast, has been shown to promote such mechanisms. When delivered in separate nanoparticle vehicles, they successfully prevent the progression of early-onset T1D autoimmunity in vivo. Herein, we show that the approach can be simplified into a single microparticle formulation of RA + TGFβ1 with surface decoration with the T1D-relevant insulin autoantigen. We show that the onset of hyperglycemia is prevented when administered into non-obese diabetic mice that are at the mid-stage of active islet-selective autoimmunity. Unexpectedly, the preventive effects do not seem to be mediated by increased numbers of regulatory T-lymphocytes inside the pancreatic lymph nodes, at least following acute administration of microparticles. Instead, we observed a mild increase in the frequency of regulatory B-lymphocytes inside the mesenteric lymph nodes. These data suggest additional and potentially-novel mechanisms that RA and TGFβ1 could be modulating to prevent progression of mid-stage autoimmunity to overt T1D. Our data further strengthen the rationale to develop RA+TGFβ1-based micro/nanoparticle “vaccines” as possible treatments of pre-symptomatic and new-onset T1D autoimmunity.

Diagnosis of Pancreatic Solid Lesions, Subepithelial Lesions, and Lymph Nodes Using Endoscopic Ultrasound.

Currently, endoscopic ultrasound (EUS) has become widely accepted and has considerable advantages over computed tomography (CT) and other imaging modalities, given that it enables echostructure assessment in lesions with <1 cm diameter and permits high resolution imaging. EUS-guided tissue acquisition (EUS-TA) provides consistent results under ultrasound guidance and has been considered more effective compared to CT- or ultrasound-guided lesion biopsy. Moreover, complication rates, including pancreatitis and bleeding, have been extremely low, with <1% morbidity and mortality rates, thereby suggesting the exceptional overall safety of EUS-TA. The aggressive use of EUS for various lesions has been key in facilitating early diagnosis and therapy. This review summarizes the diagnostic ability of EUS for pancreatic solid lesions, subepithelial lesions, and lymph nodes where it is mainly used. EUS has played an important role in diagnosing these lesions and planning treatment strategies. Future developments in EUS imaging technology, such as producing images close to histopathological findings, are expected to further improve its diagnostic ability. Moreover, tissue acquisition via EUS is expected to be used for precision medicine, which facilitates the selection of an appropriate therapeutic agent by increasing the amount of tissue collected and improving genetic analysis.

Application of three-dimensional reconstruction with a Hisense computer-assisted system in upper pancreatic lymph node dissection during laparoscopic-assisted radical gastrectomy

Background/objectiveTo investigate the feasibility of three-dimensional (3D) reconstruction with an interactive Hisense computer-assisted system (CAS) for preoperative planning and intraoperative guidance during laparoscopic-assisted upper pancreatic lymph node dissection in distal gastrectomy for gastric cancer. MethodsThis study included 28 patients who underwent preoperative 3D reconstruction of the upper border of the pancreas using Hisense CAS (3D reconstruction group) for preoperative planning and intraoperative navigation. To determine its efficacy, the clinical data of these patients were compared with those of 28 patients who did not undergo 3D reconstruction (control group). ResultsFifty-six cases of laparoscopic-assisted distal gastrectomy were performed. Three-dimensional reconstruction was successful in all the patients in the 3D reconstruction group, and real-time navigation was performed during the operation. The rate of correspondence between the 3D reconstruction images and intraoperative findings was 100%. The time taken for upper pancreatic lymph node dissection, number of upper pancreatic lymph node dissections, and number of unnecessary injuries during surgery were superior in the 3D reconstruction group than in the control group. The results of the remaining parameters were not statistically significant. ConclusionPreoperative planning with interactive Hisense CAS 3D reconstruction technology can improve surgeons’ understanding of each patient’s individual anatomy and can reveal anatomical variations, which is helpful for accurate preoperative planning and intraoperative navigation. This technique is helpful for the implementation of the precise dissection of lymph nodes at the upper edge of the pancreas and improves the quality and safety of the surgery.

Butyrate induced Tregs are capable of migration from the GALT to the pancreas to restore immunological tolerance during type-1 diabetes

Type-1 diabetes (T1D) is an autoimmune disease caused by progressive loss of insulin-producing beta cells in the pancreas. Butyrate is a commensal microbial-derived metabolite, implicated in intestinal homeostasis and immune regulation. Here, we investigated the mechanism of diabetes remission in non-obese diabetic (NOD) mice following butyrate administration. Sodium butyrate (150 mM) was administered to female NOD mice in drinking water after the onset of hyperglycemia (15–25 weeks age) and at 4 weeks of age (early-intervention group). Butyrate administration reduced the progression of hyperglycemia in diabetic mice and delayed onset of diabetes in the early-intervention group with a reduction in insulitis. Butyrate administration increased regulatory T cells (Tregs) in the colon, mesenteric lymph nodes, Peyer’s patches, and its protective effects diminished upon depletion of Tregs. Further, an increase in α4β7, CCR9, and GPR15 expressing Tregs in the pancreatic lymph nodes (PLN) and pancreas in butyrate-treated mice suggested migration of gut-primed Tregs towards the pancreas. Finally, the adoptive transfer experiments demonstrated that induced Tregs from gut-associated lymphoid tissue can migrate towards the pancreas and PLN and delay the onset of diabetes. Our results thus suggest that early administration of butyrate can restore immunological tolerance during T1D via induction of Tregs with migratory capabilities.

Endoscopic Ultrasound-Guided Fine-Needle Aspiration (EUS-FNA) with Image Enhancement.

Although endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is useful in the differential diagnosis of solid pancreatic lesions, lymph nodes, and liver lesions, inadequate sampling may result in an incorrect pathological diagnosis. The accuracy of EUS for the evaluation of pancreatobiliary lesions may be increased by image enhancement technologies, including contrast-enhanced harmonic (CH)-EUS and EUS-elastography. These methods can provide information that complement EUS-FNA for the diagnosis and staging of pancreatobiliary cancer, and can help to identify the EUS-FNA target, reducing the requirement for repeat FNA.

InsB9-23 Gene Transfer to Hepatocyte-Based Combined Therapy Abrogates Recurrence of Type 1 Diabetes After Islet Transplantation.

The induction of antigen (Ag)-specific tolerance represents a therapeutic option for autoimmune diabetes. We demonstrated that administration of a lentiviral vector enabling expression of insulin B chain 9-23 (InsB9-23) (LV.InsB) in hepatocytes arrests β-cell destruction in prediabetic NOD mice by generating InsB9-23-specific FoxP3+ T regulatory cells (Tregs). LV.InsB in combination with a suboptimal dose of anti-CD3 monoclonal antibody (combined therapy [CT], 1 × 5 μg [CT5]) reverts diabetes and prevents recurrence of autoimmunity after islet transplantation in ∼50% of NOD mice. We investigated whether CT optimization could lead to abrogation of recurrence of autoimmunity. Therefore, alloislets were transplanted after optimized CT tolerogenic conditioning (1 × 25 μg [CT25]). Diabetic NOD mice conditioned with CT25 when glycemia was <500 mg/dL remained normoglycemic for 100 days after alloislet transplantation and displayed reduced insulitis, but independently from the graft. Accordingly, cured mice showed T-cell unresponsiveness to InsB9-23 stimulation and increased Treg frequency in islet infiltration and pancreatic lymph nodes. Additional studies revealed a complex mechanism of Ag-specific immune regulation driven by CT25, in which both Tregs and PDL1 costimulation cooperate to control diabetogenic cells, while transplanted islets play a crucial role, although transient, recruiting diabetogenic cells. Therefore, CT25 before alloislet transplantation represents an Ag-specific immunotherapy to resolve autoimmune diabetes in the presence of residual endogenous β-cell mass.

CD226 Deletion Reduces Type 1 Diabetes in the NOD Mouse by Impairing Thymocyte Development and Peripheral T Cell Activation.

The costimulatory molecule CD226 is highly expressed on effector/memory T cells and natural killer cells. Costimulatory signals received by T cells can impact both central and peripheral tolerance mechanisms. Genetic polymorphisms in CD226 have been associated with susceptibility to type 1 diabetes and other autoimmune diseases. We hypothesized that genetic deletion of Cd226 in the non-obese diabetic (NOD) mouse would impact type 1 diabetes incidence by altering T cell activation. CD226 knockout (KO) NOD mice displayed decreased disease incidence and insulitis in comparison to wild-type (WT) controls. Although female CD226 KO mice had similar levels of sialoadenitis as WT controls, male CD226 KO mice showed protection from dacryoadenitis. Moreover, CD226 KO T cells were less capable of adoptively transferring disease compared to WT NOD T cells. Of note, CD226 KO mice demonstrated increased CD8+ single positive (SP) thymocytes, leading to increased numbers of CD8+ T cells in the spleen. Decreased percentages of memory CD8+CD44+CD62L– T cells were observed in the pancreatic lymph nodes of CD226 KO mice. Intriguingly, CD8+ T cells in CD226 KO mice showed decreased islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP)-tetramer and CD5 staining, suggesting reduced T cell receptor affinity for this immunodominant antigen. These data support an important role for CD226 in type 1 diabetes development by modulating thymic T cell selection as well as impacting peripheral memory/effector CD8+ T cell activation and function.

Amelioration of Autoimmune Diabetes of NOD Mice by Immunomodulating Probiotics.

Type 1 autoimmune diabetes is an autoimmune disease characterized by specific destruction of pancreatic β-cells producing insulin. Recent studies have shown that gut microbiota and immunity are closely linked to systemic immunity, affecting the balance between pro-inflammatory and regulatory immune responses. Altered gut microbiota may be causally related to the development of immune-mediated diseases, and probiotics have been suggested to have modulatory effects on inflammatory diseases and immune disorders. We studied whether a probiotic combination that has immunomodulatory effects on several inflammatory diseases can reduce the incidence of diabetes in non-obese diabetic (NOD) mice, a classical animal model of human T1D. When Immune Regulation and Tolerance 5 (IRT5), a probiotic combination comprising Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus reuteri, Bifidobacterium bifidium, and Streptococcus thermophiles, was administered 6 times a week for 36 weeks to NOD mice, beginning at 4 weeks of age, the incidence of diabetes was significantly reduced. Insulitis score was also significantly reduced, and β-cell mass was conversely increased by IRT5 administration. IRT5 administration significantly reduced gut permeability in NOD mice. The proportion of total regulatory T cells was not changed by IRT5 administration; however, the proportion of CCR9+ regulatory T (Treg) cells expressing gut-homing receptor was significantly increased in pancreatic lymph nodes (PLNs) and lamina propria of the small intestine (SI-LP). Type 1 T helper (Th1) skewing was reduced in PLNs by IRT5 administration. IRT5 could be a candidate for an effective probiotic combination, which can be safely administered to inhibit or prevent type 1 diabetes (T1D).

Prognostic value of positive histological margins in patients with pancreatic head ductal adenocarcinoma and lymph node involvement: an international multicentric study

BackgroundResection margin status and lymph node (LN) involvement are known prognostic factors for patients who undergo pancreatoduodenectomy for pancreatic ductal adenocarcinoma (PDAC). This study aimed to compare overall survival (OS) and disease-free survival (DFS) by resection margin status in patients with PDAC and LN involvement. MethodsA retrospective international multicentric study was performed including four Western centers. Multivariable Cox analysis was performed to identify prognostic factors of OS and DFS. Median OS and DFS were calculated using Kaplan–Meier curves and compared using log-rank tests. ResultsA cohort of 814 PDAC patients with pancreatoduodenectomy were analyzed. A total of 651 patients had LN involvement (80%). On multivariable analysis R1 resection was not an independent factor of worse OS and DFS in patients with LN involvement (HR 1.1, p = 0.565; HR 1.2, p = 0.174). Only tumor size, grade, and adjuvant chemotherapy were associated with OS and DFS. Median OS and DFS were similar between patients with R0 and R1 resections (23 vs. 20 months, p = 0.196; 15 vs. 14 months, p = 0.080). ConclusionResection status was not identified as predictor of OS or DFS in PDAC patients with LN involvement. Extensive surgery to achieve R0 resection in such patients might not influence the disease course.

UBASH3A deficiency accelerates type 1 diabetes development and enhances salivary gland inflammation in NOD mice

Recent advances in genetic analyses have significantly refined human type 1 diabetes (T1D) associated loci. The goal of such effort is to identify the causal genes and have a complete understanding of the molecular pathways that independently or interactively influence cellular processes leading to the destruction of insulin producing pancreatic β cells. UBASH3A has been suggested as the underlying gene for a human T1D associated region on chromosome 21. To further evaluate the role of UBASH3A in T1D, we targeted Ubash3a in NOD mice using zinc-finger nuclease mediated mutagenesis. In both 10-week-old females and males, significantly more advanced insulitis was observed in UBASH3A-deficient than in wild-type NOD mice. Consistently, UBASH3A-deficient NOD mice developed accelerated T1D in both sexes, which was associated with increased accumulation of β-cell autoreactive T cells in the spleen and pancreatic lymph node. Adoptive transfer of splenic T cells into NOD.Rag1-/- mice demonstrated that UBASH3A deficiency in T cells was sufficient to promote T1D development. Our results provide strong evidence to further support a role of UBASH3A in T1D. In addition to T1D, UBASH3A deficiency also promoted salivary gland inflammation in females, demonstrating its broad impact on autoimmunity.

Su1306 DOES SIZE MATTER? COMPARISON OF 22G VERSUS 25G FINE NEEDLE ASPIRATION IN THE DIAGNOSIS OF SOLID LESIONS

While endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) is considered a first-line strategy for sampling solid gastrointestinal tract lesions, choice of needle size remains highly variable. Therefore, the primary aim of this study was to compare the impact of needle size (22G versus 25G) in the diagnosis of solid lesions. This was a multi-center, retrospective observational study to evaluate the outcomes of EUS-guided FNA of solid lesions over a 3-year duration. Patient and lesion information as well as diagnostic test characteristics (i.e., sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV] and diagnostic accuracy), as well as adverse events were analyzed. Specimens with rapid on-site evaluation (ROSE) were excluded to avoid over-estimation of diagnostic yield. Surgical resection pathology or immunohistochemistry were considered the reference standard for diagnostic yield. A bivariate model was used to compute diagnostic characteristics, and two-sample t-tests for binomial proportions were utilized to compare strategies. A total of 284 patients underwent EUS-guided sampling of solid lesions (22G: n=169 and 25G: n=115). Baseline lesion and sampling characteristics as well as diagnostic test results are shown in Table 1. Lymph nodes (31.34%), pancreatic lesions (24.65%), subepithelial lesions (31.34%), and other lesions (12.67%) were included. Mean age of all patients was 62.83±11.67 years with no difference between groups (P=0.90). Mean lesion size was also similar [20.08±12.62 versus 18.12±11.16; P=0.21] as was number of needle passes performed [2.55±1.25 versus 2.74±1.64; P=0.26]. Route of tissue acquisition was also not different between groups (P=0.75). Overall there was no difference in sensitivity, specificity, or diagnostic accuracy between 22G versus 25G needles (P>0.05). On subgroup analyses by type of lesion, there was no difference in diagnostic yield by needle size for pancreatic lesions and lymph nodes; however, larger 22G needles demonstrated a higher accuracy for subepithelial lesions [84.62% versus 62.50%; P=0.0246]. No adverse events occurred in either group. Based upon this study, 22G needle size outperformed 25G for accurate diagnosis of subepithelial lesions. Needle size did not impact sampling of pancreatic lesions or lymph nodes. These results suggest 22G be the preferred needle size for FNA of subepithelial lesions.