Tet2 and Tet3 in B cells are required to repress CD86 and prevent autoimmunity.

A contribution of epigenetic modifications to B cell tolerance has been proposed but not directly tested. Here we report that deficiency of ten-eleven translocation (Tet) DNA demethylase family members Tet2 and Tet3 in B cells led to hyperactivation of B and T cells, autoantibody production and lupus-like disease in mice. Mechanistically, in the absence of Tet2 and Tet3, downregulation of CD86, which normally occurs following chronic exposure of self-reactive B cells to self-antigen, did not take place. The importance of dysregulated CD86 expression in Tet2- and Tet3-deficient B cells was further demonstrated by the restriction, albeit not complete, on aberrant T and B cell activation following anti-CD86 blockade. Tet2- and Tet3-deficient B cells had decreased accumulation of histone deacetylase 1 (HDAC1) and HDAC2 at the Cd86 locus. Thus, our findings suggest that Tet2- and Tet3-mediated chromatin modification participates in repression of CD86 on chronically stimulated self-reactive B cells, which contributes, at least in part, to preventing autoimmunity.

Publisher Correction: Tet2 and Tet3 in B cells are required to repress CD86 and prevent autoimmunity.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

T Follicular Helper Cell-Germinal Center B Cell Interaction Strength Regulates Entry into Plasma Cell or Recycling Germinal Center Cell Fate.

Higher- or lower-affinity germinal center (GC) B cells are directed either to plasma cell or GC recycling, respectively; however, how commitment to the plasma cell fate takes place is unclear. We found that a population of light zone (LZ) GC cells, Bcl6loCD69hi expressing a transcription factor IRF4 and higher-affinity B cell receptors (BCRs) or Bcl6hiCD69hi with lower-affinity BCRs, favored the plasma cell or recycling GC cell fate, respectively. Mechanistically, CD40 acted as a dose-dependent regulator for Bcl6loCD69hi cell formation. Furthermore, we found that expression of intercellular adhesion molecule 1 (ICAM-1) and signaling lymphocytic activation molecule (SLAM) in Bcl6loCD69hi cells was higher than in Bcl6hiCD69hi cells, thereby affording more stable T follicular helper (Tfh)-GC B cell contacts. These data support a model whereby commitment to the plasma cell begins in the GC and suggest that stability of Tfh-GC B cell contacts is key for plasma cell-prone GC cell formation.

Suppression of BMP signaling restores mitral cell development impaired by FGF signaling deficits in mouse olfactory bulb.

Fibroblast growth factors (FGFs) and bone morphogenic proteins (BMPs) play various important roles in the development of the central nervous system. However, the roles of FGF and BMP signaling in the development of the olfactory bulb (OB) are largely unknown. In this study, we first showed the expression of FGF receptors (FGFRs) and BMP receptors (BMPRs) in OB RGCs, radial glial cells (RGCs) in the developing OB, which generate the OB projection neurons, mitral and tufted cells. When the FGF signaling was inhibited by a dominant-negative form of FGFR1 (dnFGFR1), OB RGCs accelerated their state transition to mitral cell precursors without affecting their transcription cascade and fate. However, the mitral cell precursors could not radially migrate to form the mitral cell layer (MCL). In addition, FGF signaling inhibition reduced the expression of a BMP antagonist, Noggin, in the developing OB. When BMP signaling was suppressed by the ectopic expression of Noggin or a dominant-negative form of BMPR1a (dnBMPR1a) in the developing OB, the defect in MCL formation caused by the dnFGFR1 was rescued. However, the dnBMPR1a did not rescue the accelerated state transition of OB RGCs. These results demonstrate that FGF signaling is important for OB RGCs to maintain their self-renewal state and MCL formation. Moreover, the suppression of BMP signaling is required for mitral cells to form the MCL. This study sheds new light on the roles of FGFs and BMPs in OB development.

[A Case of Desmoid Fibromatosis of the Small Intestinal Mesentery Institutions].

The patient was a 27-year-old man. He was referred to our hospital because he was aware of a mass in his abdomen. An abdominal ultrasound showed a 70-mm mass lesion. Enhanced computed tomography showed a 70-mm mass with well- defined margins and heterogeneous internal enhancement near the proximal jejunum. The patient was diagnosed with a suspected primary submucosal tumor of the duodenum or small intestine, and surgery was planned to diagnose and treat the tumor. The tumor was located in the upper jejunal mesentery, and tumor resection and partial small bowel resection were performed. Histopathological examination revealed proliferation of spindle-shaped cells without karyomitosis, and mixed collagen fibers in the tissue. Immunohistochemistry showed ß-catenin(+), SMA(+), AE1/AE3(-), KIT(-), CD34(-), and S-100(-). Based on these findings, we diagnosed primary desmoid fibromatosis of the small intestinal mesentery. In this report, we describe a case of primary desmoid fibromatosis of the small intestinal mesentery with a review of the literature.

Incidental Bladder Cancer Found on Cystoscopy during Prostate Biopsy: Prevalence, Pathological Findings, and Oncological Outcome.

INTRODUCTION: We examined the prevalence, pathological findings, and oncological outcomes of incidental bladder cancer found on cystoscopy among patients eligible for prostate biopsy (PB). METHODS: We retrospectively reviewed 803 patients who underwent cystoscopy prior to PB between January 2010 and September 2020. In cases of bladder tumor-like findings on cystoscopy, biopsy or transurethral resection of the bladder tumor was performed. The primary and secondary outcomes were the prevalence of incidental bladder cancer and pathological and oncological outcomes of incidental bladder cancer, respectively. RESULTS: Incidental findings were observed in 31/803 patients (3.9%). Bladder tumor-like findings were found in 24/803 patients (3%), while 9/803 patients (1.1%) were pathologically diagnosed with urothelial carcinoma. The stage and grade of incidental bladder cancer were pTa in 8/9 patients and pT1 in 1/9 and low grade in 8/9 and high in 1/9, respectively. The median tumor size of the papillary pedunculated type was 0.5 cm. At 26-month median follow-up, no recurrence was observed. CONCLUSION: Cystoscopy during PB may yield incidental bladder cancer findings, although the prevalence is very low. Incidental bladder cancer was of low stage and grade, which seemed unrelated to survival. Moreover, performing routine cystoscopy in conjunction with PB is not recommended as it may lead to overdiagnosis of low-risk bladder cancer.

Bihormonal dysregulation of insulin and glucagon contributes to glucose intolerance development at one year post-delivery in women with gestational diabetes: a prospective cohort study using an early postpartum 75-g glucose tolerance test.

Gestational diabetes mellitus (GDM) is known to be a significant risk factor for the future development of type 2 diabetes. Here, we investigated whether a precise evaluation of ß- and α-cell functions helps to identify women at high risk of developing glucose intolerance after GDM. Fifty-six women with GDM underwent a 75-g oral glucose tolerance test (OGTT) at early (6-12 weeks) postpartum. We measured their concentrations of glucose, insulin, proinsulin and glucagon at fasting and 30, 60 and 120 min. At 1-year post-delivery, we classified the women into a normal glucose tolerance (NGT) group or an impaired glucose tolerance (IGT)/diabetes mellitus (DM) group. Forty-three of the 56 women completed the study. At 1-year post-delivery, 17 women had developed IGT/DM and 26 women showed NGT. In the early-postpartum OGTTs, the IGT/DM group showed a lower insulinogenic index, a less glucagon suppression evaluated by the change from fasting to 30 min (ΔGlucagon 30 min), and a higher glucagon-to-insulin ratio at 30 min compared to the NGT group. There were no significant between-group differences in proinsulin levels or proinsulin-to-insulin ratios. Insulinogenic index <0.6 and ΔGlucagon 30 min >0 pg/mL were identified as predictors for the development of IGT/DM after GDM, independent of age, body mass index, and lactation intensity. These results suggest that the bihormonal disorder of insulin and glucagon causes the postpartum development of glucose intolerance. The measurement of plasma insulin and glucagon during the initial OGTT at early postpartum period can help to make optimal decisions regarding the postpartum management of women with GDM.

Implication of Perifollicular Clusters and Folliculotropic Distribution of Dendritic Cells in the Pathogenesis of Seborrhoeic Dermatitis.

The pathogenesis of seborrhoeic dermatitis is controversial and remains unclear. Malassezia is considered to be a commensal fungi and is found not only in the stratum corneum but also in hair follicles. It is an important pathogenic factor in seborrhoeic dermatitis. The aim of this study was to clarify the pathogenesis of seborrhoeic dermatitis, morphologically, through comparison with psoriasis vulgaris. Fifteen cases of seborrhoeic dermatitis, 7 of psoriasis, and 6 of normal skin were examined using routine histopathology, immunohistochemistry, and electron microscopy. Macrophages were found to be diffusely distributed in the upper dermis of seborrhoeic dermatitis and psoriasis. In contrast, a significant increase in the number of dendritic cells in the follicular epithelium and dendritic cell clusters in the perifollicular dermis were found only in seborrhoeic dermatitis. Ultrastructural examination of the clusters demonstrated that dendritic cells interacted with lymphocytes, macrophages, and other dendritic cells. In conclusion, folliculotropic distribution of dendritic cells as well as dendritic cell-immune cell clusters play an important role in the pathogenesis of seborrhoeic dermatitis.

VISCERAL AND SUBCUTANEOUS FAT INCREASED AFTER TREATMENT OF GRAVES DISEASE.

Objective: Patients with Graves disease (GD) tend to gain weight after treatment, but it remains unknown if weight gain is associated with an increase in the visceral and/or subcutaneous fat areas (VFA, SFA). Methods: We enrolled 25 newly diagnosed GD patients (22 females, median age 33.0 years) and studied their clinical parameters, and VFA and SFA measured by a dual bioelectric impedance analysis. We divided them into 2 groups based on the rates of change in the VFA and SFA, and we compared clinical parameters at the baseline between the groups to evaluate factors that influence increases in the VFA and/or SFA with treatment. Results: The patients' body weight (BW), VFA, and SFA were significantly increased after a 6-month treatment (BW: from 54.3 ± 10.3 kg to 58.0 ± 11.2 kg; P<.001; VFA: from 47.1 ± 21.3 cm2 to 54.7 ± 23.4 cm2; P = .004; SFA: from 159.8 ± 85.9 cm2 to 182.2 ± 82.9 cm2; P = .008). The percent changes of BW correlated with the SFA (ρ = .591, P = .002), but not with the VFA. The patients with larger VFA increases had significantly less VFA at the baseline compared to those with smaller increases, expressed as median and interquartile range (33.9 cm2 [22.7 to 47.5 cm2] versus 54.5 cm2 [45.2 to 64.0], respectively; P = .011). A larger increase in the SFA was negatively associated with serum alkaline phosphatase. An increase in the SFA was associated with free triiodothyronine (T3) in a multivariate logistic analysis (odds ratio: 0.80 [0.59 to 0.97]; P = .013). Conclusion: The patients' BW, VFA, and SFA were increased after GD treatment. The increase in SFA seemed to contribute to weight gain and was associated with a low baseline level of free T3. Abbreviations: ALP = alkaline phosphatase; BMI = body mass index; BW = body weight; GD = Graves disease; SFA = subcutaneous fat area; T3 = triiodothyronine; T4 = thyroxine; TG = triglycerides; VFA = visceral fat areas.

RENAL FUNCTION AND PLASMA RENIN ACTIVITY AS POTENTIAL FACTORS CAUSING HYPERKALEMIA IN PATIENTS WITH THYROID CARCINOMA UNDERGOING THYROID HORMONE WITHDRAWAL FOR RADIOACTIVE IODINE THERAPY.

Objective: Hypothyroidism is not commonly considered a cause of hyperkalemia. We previously reported that hyperkalemia was observed mainly in elderly patients treated with renin-angiotensin-aldosterone system (RAS) inhibitors when levothyroxine treatment was withdrawn for the thyroidectomized patients with thyroid carcinoma to undergo radioactive iodine treatment. Here, we investigated whether acute hypothyroidism causes hyperkalemia in patients who were not treated with RAS inhibitors. We also investigated factors influencing potassium metabolism in hypothyroid patients. Methods: We conducted a single-center, prospective cohort study of 46 Japanese patients with thyroid carcinoma undergoing levothyroxine withdrawal prior to radioiodine therapy. All patients were normokalemic before levothyroxine withdrawal. Blood samples were analyzed 3 times: before, and at 3 and 4 weeks after levothyroxine withdrawal. We investigated factors that may be associated with the elevation of serum potassium levels from a euthyroid state to a hypothyroid state. Results: None of the patients developed symptomatic hyperkalemia. The mean serum potassium level was significantly higher at 4 weeks after levothyroxine withdrawal compared to baseline. The serum sodium levels, the estimated glomerular filtration rate (eGFR), and the plasma renin activity (PRA) decreased significantly as hypothyroidism advanced. In contrast, the plasma levels of adrenocorticotropic hormone, cortisol, aldosterone, and antidiuretic hormone were not changed, while serum thyroid hormone decreased. At 4 weeks after their levothyroxine withdrawal, the patients' serum potassium values were significantly correlated with the eGFR and the PRA. Conclusion: Acute hypothyroidism can cause a significant increase in the serum potassium level, which may be associated with a decreased eGFR and decreased circulating RAS. Abbreviations: ACTH = adrenocorticotropic hormone; ADH = antidiuretic hormone; ATPase = adenosine triphosphatase; eGFR = estimated glomerular filtration rate; HbA1c = glycated hemoglobin; K+ = potassium; Na+ = sodium; PRA = plasma renin activity; RAS = renin-angiotensin-aldosterone system; T4 = thyroxine; TSH = thyroid-stimulating hormone.

Usefulness of septal thickness measurement on endoscopic ultrasound as a predictor of malignancy of branched-duct and mixed-type intraductal papillary mucinous neoplasm of the pancreas.

BACKGROUND AND AIM: Septal thickness (ST) can predict a malignant branch-duct (BD) and mixed-type intraductal papillary mucinous neoplasm (IPMN) of the pancreas, but its cut-off value has not been established. The aim of the present study was to determine the optimal ST cut-off value to predict malignancy using endoscopic ultrasound (EUS). METHODS: We retrospectively identified 200 patients with IPMN, including 132 with BD- and mixed-IPMN, who underwent surgical resection between 1989 and 2017. ST was defined as the septum or lesion wall with the maximum diameter in BD- and mixed-IPMN. The possibility of ST as a malignant predictor was examined, as well as the diagnostic ability of ST combined with mural nodule (MN) height for malignant IPMN. RESULTS: Among the 132 IPMN patients, pathological diagnosis was benign in 81 (61.4%) and malignant in 51 (38.6%). Area under the curve for the diagnosis of malignancy using ST was 0.74 for pathological specimens, 0.70 for EUS and 0.56 for computed tomography. Multivariate analysis showed that the odds ratios for ST ≥2.5 mm and MN height ≥5 mm were 3.51 [95% confidence interval (CI), 1.55-7.97, P = 0.003] and 3.36 (95% CI, 1.52-7.45, P = 0.003), respectively. CONCLUSIONS: Septal thickness was an independent predictive factor similar to MN height for malignant IPMN in a multivariate analysis. The ST on EUS appeared to be the thickness of a fibrotic septum associated with the malignant transformation of IPMN. An ST cut-off value of 2.5 mm might provide an accurate prediction of malignant IPMN.

Efficacy of the 6-mm fully covered self-expandable metal stent during endoscopic ultrasound-guided hepaticogastrostomy as a primary biliary drainage for the cases estimated difficult endoscopic retrograde cholangiopancreatography: A prospective clinical study.

BACKGROUND AND AIM: Endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) is performed as an alternative to the percutaneous or surgical approach. Despite high success rates, the adverse events rate is high. Recently, we used 6-mm fully covered self-expandable metal stents to prevent adverse events and allow easy re-intervention. The purposes were to evaluate the safety, feasibility, and clinical efficacy. METHODS: A prospective study to confirm the safety of EUS-HGS was carried out in six patients, followed by a trial to evaluate the feasibility and efficacy of EUS-HGS in approximately 12 additional patients. We permitted a total of 18 to 20 patients in consideration of possibility such as the deviation after providing informed consent. RESULTS: Twenty patients underwent EUS-HGS. No treatment-related adverse events described in the safety assessment criteria were seen. The technical and clinical success rates were 100% and 95%. The adverse event rate was 15%. Focal cholangitis was seen in two patients and fever in one patient. All cases were treated conservatively. Stent dysfunction was seen in 10 patients. The causes of stent dysfunction were biliary sludge (n = 6) and stent dislocation (n = 4). In nine cases, a new stent was easily inserted. Percutaneous drainage was selected in only one patient because of worsening general condition. CONCLUSIONS: The 6-mm fully covered self-expandable metal stent is safe and effective, especially for avoiding serious adverse events and allowing easy re-intervention. (UMIN000006785).

Concurrent Double Fungal Infections of the Skin Caused by Phialemoniopsis endophytica and Exophiala jeanselmei in a Patient with Microscopic Polyangiitis.

is missing (Short communication).

Pseudocheckerboard pattern: an interesting histopathological finding in mechanic's hands.

BACKGROUND: Mechanic's hands are a well-known symptom often associated with dermatomyositis and are similar to hand eczema clinically. Histopathology of them usually shows hyperkeratosis, focal parakeratosis, psoriasiform acanthosis, basal vacuolar changes and necrotic keratinocytes in the epidermis and upper dermal mucin deposition. However, there have been few comparative histopathologic evaluations of mechanic's hands and palmoplantar eczema. METHODS: We evaluated the histopathology of mechanic's hands in 6 patients with dermatomyositis who visited our hospital between 2006 and 2014 comparing with histopathology of 27 patients with palmoplantar eczema, retrospectively. RESULTS: As previously reported, hyperkeratosis, basal vacuolar change and necrotic keratinocytes were seen in all cases of mechanic's hands. Basal vacuolar change was not observed in any cases of palmoplantar eczema. Three cases of mechanic's hands demonstrated a characteristic finding, a pseudocheckerboard pattern, in the hyperkeratotic horny layer; there were areas of alternating parakeratosis and orthokeratosis in a vertical arrangement and these areas alternated with the completely orthokeratotic areas in a horizontal arrangement. This pattern has not been focused in mechanic's hands so far. Same pattern was also observed in four patients with palmoplantar eczema. CONCLUSION: 'Pseudocheckerboard pattern' was not specific but may be a possible diagnostic clue for mechanic's hands.

The combinatorial guidance activities of draxin and Tsukushi are essential for forebrain commissure formation.

We have shown that draxin is a repulsive axon guidance molecule for a variety of neuron classes and that genetic deletion of draxin in mice results in the absence of all forebrain commissures. Moreover, we also identified a secreted molecule, Tsukushi (TSK), that belongs to the small leucine-rich proteoglycan family (SLRP) and inhibits signaling molecules, such as BMP and Wnt. TSK knockout mice show malformation of the corpus callosum (CC) and agenesis of the anterior commissure (AC), suggesting the importance of TSK function in forebrain commissure formation. There is a possibility that the combined function of these two proteins is essential for the formation of these commissures. In this study, we investigate this possibility by generating draxin/TSK doubly heterozygous mice and comparing their forebrain commissure phenotypes with those of singly heterozygous mice. We found that, although draxin and TSK did not interact directly, their genetic interaction was evident from the significantly higher prevalence of CC malformation and agenesis of the AC in the draxin/TSK doubly heterozygous mice. Importantly, in this study, we demonstrated a new function of TSK in guiding anterior olfactory neuronal (AON) and cortical axons. TSK bound to and provided growth inhibitory signals dose-dependently to AON and cortical axons in outgrowth assay. TSK also induced growth cone collapse when applied acutely to these cultured neurons. Furthermore, TSK and draxin had additive effects in inhibiting cortical and AON neurite outgrowth. Thus, based on a combination of genetic analyses and in vitro experiments, we propose that the combined guidance activities of draxin and TSK regulate forebrain commissure formation.

Tsukushi functions as a Wnt signaling inhibitor by competing with Wnt2b for binding to transmembrane protein Frizzled4.

The Wnt signaling pathway is essential for the development of diverse tissues during embryogenesis. Signal transduction is activated by the binding of Wnt proteins to the type I receptor low-density lipoprotein receptor-related protein 5/6 and the seven-pass transmembrane protein Frizzled (Fzd), which contains a Wnt-binding site in the form of a cysteine-rich domain. Known extracellular antagonists of the Wnt signaling pathway can be subdivided into two broad classes depending on whether they bind primarily to Wnt or to low-density lipoprotein receptor-related protein 5/6. We show that the secreted protein Tsukushi (TSK) functions as a Wnt signaling inhibitor by binding directly to the cysteine-rich domain of Fzd4 with an affinity of 2.3 × 10(-10) M and competing with Wnt2b. In the developing chick eye, TSK is expressed in the ciliary/iris epithelium, whereas Wnt2b is expressed in the adjacent anterior rim of the optic vesicle, where it controls the differentiation of peripheral eye structures, such as the ciliary body and iris. TSK overexpression effectively antagonizes Wnt2b signaling in chicken embryonic retinal cells both in vivo and in vitro and represses Wnt-dependent specification of peripheral eye fates. Conversely, targeted inactivation of the TSK gene in mice causes expansion of the ciliary body and up-regulation of Wnt2b and Fzd4 expression in the developing peripheral eye. Thus, we uncover a crucial role for TSK as a Wnt signaling inhibitor that regulates peripheral eye formation.