Patent blue interferes with the measurement of lipemia index in a patient with sentinel lymph node.

Lipids interfere with absorbance measurements conducted using colorimetric methods. To monitor lipemia, some systems measure absorbance using an analyzer. This report describes a novel case of interference with the lipemia index without lipemia. A 64-year-old woman with giant basal cell carcinoma underwent resection and sentinel lymph node biopsy. The patient had been subcutaneously injected with patent blue during sentinel lymph node resection. After surgery, her serum and urine were yellow-green, and the lipemia index, calculated by measuring absorbance at 658 nm (main wavelength) and 694 nm (secondary wavelength) using a JCA-BM8040 chemistry analyzer, was high. The absorbance spectrum of the patient's serum and patent blue solution were compared to determine the cause of the high lipemia index. The patient's serum and the patent blue solution showed absorption at wavelengths between 540 and 698 nm. Moreover, the absorbance was concentration-dependent for patent blue. These results thus indicated that the patient's serum contained patent blue. Here, we report a case wherein patent blue affected the lipemia index. Thus, it must be noted that patent blue injection may yield inaccurate results when evaluating lipemia index.

IgG4-IgE complex interferes with measurement of IgE concentration.

BACKGROUND AND AIMS: Patients with immunoglobulin G4 (IgG4)-related disease (IgG4-RD) have elevated immunoglobulin E (IgE) concentration compared to that in healthy individuals, which suggests the occurrence of IgE-mediated allergic reactions. We have previously shown that IgG4 and IgE form a complex in some patients with IgG4-RD. However, it is currently unknown whether and how the presence of the IgG4-IgE complex affects IgE concentration measurements by different assays. MATERIALS AND METHODS: Twenty patients with confirmed presence or absence of IgG4-IgE complex were evaluated. We compared IgE concentrations measured by ST AIA-PACK IgE II (AIA-PACK), Elecsys IgE II Immunoassay (Elecsys), and Iatroace IgE (Iatroace) and evaluated to what extent the IgG4-IgE complex interfered with these measurements. RESULTS: In patients with the IgG4-IgE complex, IgE concentrations measured using Iatroace were significantly lower than those measured using Elecsys and tended to be lower than those measured using AIA-PACK. IgE concentrations determined by Iatroace were significantly different in patients with and without the IgG4-IgE complex, whereas no significant differences between these groups were detected when IgE concentrations were measured by AIA-PACK or Elecsys. CONCLUSION: The formation of the IgG4-IgE complex underestimates measured IgE concentrations depending on the method used. Therefore, caution should be exercised when selecting a specific IgE assay for patients with IgG4-RD.

Abnormal glomerular basement membrane maturation impairs mesangial cell differentiation during murine postnatal nephrogenesis.

Although mesangial cell-glomerular basement membrane (GBM) connections play a key role in maintaining the glomerular capillary loop structure, information remains limited about how these connections are formed during glomerulogenesis. We have previously shown that weakened podocyte-GBM interactions owing to tensin 2 (Tns2) deficiency lead to abnormal GBM maturation during postnatal glomerulogenesis. Here, we investigated whether abnormal GBM maturation affected mesangial cell-GBM connections and mesangial cell differentiation. Histological analysis of the outer cortical glomeruli in Tns2-deficient mice revealed that GBM materials overproduced by stressed immature podocytes accumulated in the mesangium and interrupted the formation of mesangial cell-GBM connections, resulting in fewer capillary loops compared with that of normal glomeruli. In addition, expression of α-smooth muscle actin, an immature mesangial cell marker, persisted in mesangial cells of Tns2-deficient outer cortical glomeruli even after glomerulogenesis was completed, resulting in mesangial expansion. Furthermore, analysis of mouse primary mesangial cells revealed that mesangial cell differentiation depended on the type of extracellular matrix components to which the cells adhered, suggesting the participation of mesangial cell-GBM connections in mesangial cell differentiation. These findings suggest that abnormal GBM maturation affects mesangial cell differentiation by impairing mesangial cell-GBM connections.NEW & NOTEWORTHY Mesangial cell-glomerular basement membrane (GBM) connections play an important role in maintaining the structural integrity of the glomerular tuft. However, information remains scarce about how GBM maturation affects the formation of these connections during glomerular development. Here, we show that abnormal GBM maturation due to tensin 2 deficiency affects mesangial cell differentiation by impairing mesangial cell-GBM connections during postnatal glomerulogenesis.

Frequencies of Anti-Troponin I vs Anti-Troponin T Autoantibodies and Degrees of Interference on Troponin Assays.

OBJECTIVE: Presence of autoantibodies against troponin I (cTnI) or T (cTnT) has been reported to interfere with troponin assays. However, the extent of the interference with the measurement has not been explored sufficiently. The aims of this study were to examine the frequencies of autoantibodies against troponin I and troponin T and how much these antibodies would affect the measurement. METHODS: The study comprised 52 subjects who visited Hokkaido University Hospital with suspected ischemic heart diseases. To evaluate the presence of autoantibodies, we calculated the recoveries of cTnI or cTnT after immunoglobulin G depletion, and the distributions of peaks reactive with cTnI or cTnT by high-performance liquid chromatography were examined. RESULTS: Autoantibodies against cTnI and cTnT were identified in 8 subjects (15.4%) and 1 subject (1.9%), respectively. Although the greatest difference between cTnI and cTnT was 32-fold, the distributions of cTnI-to-cTnT ratios in groups with and without anti-cTnI were not statistically different. CONCLUSION: Autoantibodies against cTnI were more frequent by several fold than those against cTnT. Their presence did not significantly expand the discrepancy between cTnI and cTnT assays.

Enhancement of Regnase-1 expression with stem loop-targeting antisense oligonucleotides alleviates inflammatory diseases.

Regnase-1 is an ribonuclease that plays essential roles in restricting inflammation through degrading messenger RNAs (mRNAs) involved in immune reactions via the recognition of stem-loop (SL) structures in the 3' untranslated regions (3'UTRs). Dysregulated expression of Regnase-1 is associated with the pathogenesis of inflammatory and autoimmune diseases in mice and humans. Here, we developed a therapeutic strategy to suppress inflammatory responses by blocking Regnase-1 self-regulation, which was mediated by the simultaneous use of two antisense phosphorodiamidate morpholino oligonucleotides (MOs) to alter the binding of Regnase-1 toward the SL structures in its 3'UTR. Regnase-1-targeting MOs not only enhanced Regnase-1 expression by stabilizing mRNAs but also effectively reduced the expression of multiple proinflammatory transcripts that were controlled by Regnase-1 in macrophages. Intratracheal administration of Regnase-1-targeting MOs ameliorated acute respiratory distress syndrome and chronic fibrosis through suppression of inflammatory cascades. In addition, intracranial treatment with Regnase-1-targeting MOs attenuated the development of experimental autoimmune encephalomyelitis by promoting the expansion of homeostatic microglia and regulatory T cell populations. Regnase-1 expression was inversely correlated with disease severity in patients with multiple sclerosis, and MOs targeting human Regnase-1 SL structures were effective in mitigating cytokine production in human immune cells. Collectively, MO-mediated disruption of the Regnase-1 self-regulation pathway is a potential therapeutic strategy to enhance Regnase-1 abundance, which, in turn, provides therapeutic benefits for treating inflammatory diseases by suppressing inflammation.

IgG4-IgE complex in patients with IgG4-related disease.

BACKGROUND: IgG4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory disease characterized by high IgE levels; however, the physiological significance of elevated IgE levels in patients with IgG4-RD is unclear. Previously, we reported the formation of IgG4-IgE complex in IgG4-RD patients with elevated IgE levels. In this study, we examined the frequency of this complex formation and its relationship with the clinical features in IgG4-RD patients. METHODS: The IgG4-IgE complex was evaluated in 33 and 17 patients with and without IgG4-RD, respectively. The IgG4-IgE complex was evaluated by performing the immunoadsorption of IgG4 using anti-IgG4 antibody-conjugated matrices. RESULTS: The frequency of IgG4-IgE complex formation in patients with IgG4-RD was significantly higher than that in those without IgG4-RD (21.2% vs. 0%). No significant differences were observed between the groups in terms of clinical characteristics and laboratory data. However, the IgG4-IgE complex-positive group had a significantly higher frequency of pancreatic lesions (85.7% vs. 42.3%) and a significantly lower rate of retroperitoneal fiber/periarterial lesions (0% vs. 38.5%) than the IgG4-IgE complex-negative group. CONCLUSION: The IgG4-IgE complex was found only in patients with IgG4-RD which may provide some clues to the pathogenesis and etiology of IgG4-RD.

IgG4-IgE complex in a patient with IgG4-related disease.

BACKGROUND: IgE concentrations are occasionally elevated in patients with IgG4-related disease (IgG4-RD). In this report, we describe a novel case of IgG4-RD in which IgE concentrations were discordant between measuring reagents. CASE: An 81-year-old man was diagnosed with IgG4-RD and histological autoimmune pancreatitis, which ensued without treatment. The IgE concentrations measured using Elecsys IgE II Immunoassay and Iatroace IgE were 1287.0 IU/mL and 60.9 IU/mL, respectively. IgG4 concentration was 675 mg/dL. METHODS: To identify IgG and IgG4 directly bound to IgE, purification using protein G and anti-IgG4 antibody-conjugated matrixes and size-exclusion high-performance liquid chromatography (HPLC) were performed. RESULTS: In purification analysis, the IgE concentration of the flow-through and bound fractions were 6.8 IU/mL (10.8%) and 56.2 IU/mL (89.2%) for IgG purification and 6.8 IU/mL (12.2%) and 49.0 IU/mL (87.8%) for IgG4 purification. IgE was eluted as a single peak (640 kDa) using size-exclusion HPLC. In the elution pattern of IgG4, a minor peak (640 kDa) and a major peak (170 kDa) were observed. These results indicate that IgG4 binds to IgE and forms a complex, resulting in a discrepancy between reagents. CONCLUSIONS: In this report, we present an IgG4-IgE complex in a patient with IgG4-RD, which affected the discrepancy in IgE concentrations between IgE reagents. This report points to the significance of increased IgE production in IgG4-RD.

Performance of Qualitative and Quantitative Antigen Tests for SARS-CoV-2 Using Saliva.

The rapid detection of SARS-CoV-2 is critical for the prevention of disease outbreaks. Antigen tests such as immunochromatographic assay (ICA) and chemiluminescent enzyme immunoassay (CLEIA) can yield results more quickly than PCR. We evaluated the performance of ICA and CLEIA using 34 frozen PCR-positive (17 saliva samples and 17 nasopharyngeal swabs [NPS]) and 309 PCR-negative samples. ICA detected SARS-CoV-2 in only 14 (41%) samples, with positivity rates of 24% in saliva and 59% in NPS. Notably, ICA detected SARS-CoV-2 in 5 of 6 samples collected within 4 days after symptom onset. CLEIA detected SARS-CoV-2 in 31 (91%) samples, with a positivity of 82% in saliva and 100% in NPS. These results suggest that the use of ICA should be limited to an earlier time after symptom onset and CLEIA is more sensitive and can be used in situations where quick results are required.

Distinct Foxp3 enhancer elements coordinate development, maintenance, and function of regulatory T cells.

The transcription factor Foxp3 plays crucial roles for Treg cell development and function. Conserved non-coding sequences (CNSs) at the Foxp3 locus control Foxp3 transcription, but how they developmentally contribute to Treg cell lineage specification remains obscure. Here, we show that among Foxp3 CNSs, the promoter-upstream CNS0 and the intergenic CNS3, which bind distinct transcription factors, were activated at early stages of thymocyte differentiation prior to Foxp3 promoter activation, with sequential genomic looping bridging these regions and the promoter. While deletion of either CNS0 or CNS3 partially compromised thymic Treg cell generation, deletion of both completely abrogated the generation and impaired the stability of Foxp3 expression in residual Treg cells. As a result, CNS0 and CNS3 double-deleted mice succumbed to lethal systemic autoimmunity and inflammation. Thus, hierarchical and coordinated activation of Foxp3 CNS0 and CNS3 initiates and stabilizes Foxp3 gene expression, thereby crucially controlling Treg cell development, maintenance, and consequently immunological self-tolerance.

Tensin2 is important for podocyte-glomerular basement membrane interaction and integrity of the glomerular filtration barrier.

Tensin2 (Tns2), an integrin-linked protein, is enriched in podocytes within the glomerulus. Previous studies have revealed that Tns2-deficient mice exhibit defects of the glomerular basement membrane (GBM) soon after birth in a strain-dependent manner. However, the mechanisms for the onset of defects caused by Tns2 deficiency remains unidentified. Here, we aimed to determine the role of Tns2 using newborn Tns2-deficient mice and murine primary podocytes. Ultrastructural analysis revealed that developing glomeruli during postnatal nephrogenesis exhibited abnormal GBM processing due to ectopic laminin-α2 accumulation followed by GBM thickening. In addition, analysis of primary podocytes revealed that Tns2 deficiency led to impaired podocyte-GBM interaction and massive expression of laminin-α2 in podocytes. Our study suggests that weakened podocyte-GBM interaction due to Tns2 deficiency causes increased mechanical stress on podocytes by continuous daily filtration after birth, resulting in stressed podocytes ectopically producing laminin-α2, which interrupts GBM processing. We conclude that Tns2 plays important roles in the podocyte-GBM interaction and maintenance of the glomerular filtration barrier.

Identification of a New Theca/Interstitial Cell-Specific Gene and Its Biological Role in Growth of Mouse Ovarian Follicles at the Gonadotropin-Independent Stage.

Theca/interstitial cells are responsible for the growth and maturation of ovarian follicles. However, little is known about the theca/interstitial cell-specific genes and their functions. In this study, we explored transcriptomes of theca/interstitial cells by RNA-seq, and the novel biological roles of a theca cell marker, asporin (Aspn)/periodontal ligament-associated protein 1 (PLAP-1). RNA-seq detected 432 and 62 genes expressed specifically in theca/interstitial cells and granulosa cells isolated from 3-weeks old mouse ovaries. Gene ontology analysis demonstrated that these genes were largely categorized into four major groups: extracellular matrix organization-related terms, chemotaxis-related terms, the angiogenesis-related terms, and morphogenesis-related terms. In situ hybridization demonstrated that the newly detected representative gene, Aspn/PLAP-1, was detected specifically in the outer layer of theca cells in contrast with the expression of the basal lamina-specific gene, Nidgen-1. Intriguingly, an Aspn/PLAP-1 antibody completely arrested the growth of secondary follicles that is the gonadotropin-independent follicle developmental stage. Furthermore, transforming growth factor-ß (TGF-ß)-triggered signaling was induced by the Aspn/PLAP-1 antibody treatment, which is consistent with the inhibitory effect of Aspn/PLAP-1 on TGF-ß. Altogether, these results suggest that theca cells are classified into subpopulations on the basis of new marker genes and their biological functions, and provide evidence that Aspn/PLAP-1 is expressed exclusively in the outer layer of theca cells and plays a pivotal role in the growth of secondary follicles via downregulation of the canonical TGF-ß signaling cascade.

Dynamics of D-serine reflected the recovery course of a patient with rapidly progressive glomerulonephritis.

We experienced a case of a 36-year-old female with rapidly progressive glomerulonephritis (RPGN) due to anti-neutrophil cytoplasmic antibody (ANCA)-associated nephritis and systemic lupus erythematosus (SLE) nephritis. Chiral amino acid metabolomics revealed a prominent profile of D-serine in this patient. At the fulminant period of RPGN, the level of plasma D-serine, a potential biomarker in CKD that reflects actual glomerular filtration ratio (GFR), was extremely high. On the other hand, urinary fractional excretion (FE) of D-serine, which was usually much higher than that of L-isoform, was 0% in this patient. These abnormal D-serine profiles normalized in response to the intensive treatment. Normalizations of blood D-serine levels were in parallel with those of blood creatinine levels and potentially reflect the recovery of GFR. FE of D-serine increased transiently before the normalization of D-serine profile, suggesting that kidney promotes urinary excretion of D-serine for the normalization of plasma D-serine level. These unexplored clinical features of D-serine well reflected the clinical course of this patient. Blood D-serine level can also serve as a biomarker in acute kidney injury (AKI) or RPGN, and, in combination with FE of D-serine, may render the clinical practitioners to judge the efficacy of intensive treatments.

Identification of a genomic enhancer that enforces proper apoptosis induction in thymic negative selection.

During thymic negative selection, autoreactive thymocytes carrying T cell receptor (TCR) with overtly strong affinity to self-MHC/self-peptide are removed by Bim-dependent apoptosis, but how Bim is specifically regulated to link TCR activation and apoptosis induction is unclear. Here we identify a murine T cell-specific genomic enhancer EBAB (Bub1-Acoxl-Bim), whose deletion leads to accumulation of thymocytes expressing high affinity TCRs. Consistently, EBAB knockout mice have defective negative selection and fail to delete autoreactive thymocytes in various settings, with this defect accompanied by reduced Bim expression and apoptosis induction. By contrast, EBAB is dispensable for maintaining peripheral T cell homeostasis via Bim-dependent pathways. Our data thus implicate EBAB as an important, developmental stage-specific regulator of Bim expression and apoptosis induction to enforce thymic negative selection and suppress autoimmunity. Our study unravels a part of genomic enhancer codes that underlie complex and context-dependent gene regulation in TCR signaling.

Correction to: The pathogenicity of Th17 cells in autoimmune diseases.

Unfortunately, an error occurred in the following passus of the article. The word "receptor" was missing in the sentence "Because T cells do not express GM-CSF receptor [41], GM-CSF affects non-T cells."

The pathogenicity of Th17 cells in autoimmune diseases.

IL-17-producing T helper (Th17) cells have been implicated in the pathogenesis of many inflammatory and autoimmune diseases. Targeting the effector cytokines IL-17 and GM-CSF secreted by autoimmune Th17 cells has been shown to be effective for the treatment of the diseases. Understanding a molecular basis of Th17 differentiation and effector functions is therefore critical for the regulation of the pathogenicity of tissue Th17 cells in chronic inflammation. Here, we discuss the roles of proinflammatory cytokines and environmental stimuli in the control of Th17 differentiation and chronic tissue inflammation by pathogenic Th17 cells in humans and in mouse models of autoimmune diseases. We also highlight recent advances in the regulation of pathogenic Th17 cells by gut microbiota and immunometabolism in autoimmune arthritis.

Satb1 regulates the effector program of encephalitogenic tissue Th17 cells in chronic inflammation.

The genome organizer, special AT-rich sequence-binding protein-1 (Satb1), plays a pivotal role in the regulation of global gene networks in a cell type-dependent manner and is indispensable for the development of multiple cell types, including mature CD4+ T, CD8+ T, and Foxp3+ regulatory T cells in the thymus. However, it remains unknown how the differentiation and effector program of the Th subsets in the periphery are regulated by Satb1. Here, we demonstrate that Satb1 differentially regulates gene expression profiles in non-pathogenic and pathogenic Th17 cells and promotes the pathogenic effector program of encephalitogenic Th17 cells by regulating GM-CSF via Bhlhe40 and inhibiting PD-1 expression. However, Satb1 is dispensable for the differentiation and non-pathogenic functions of Th17 cells. These results indicate that Satb1 regulates the specific gene expression and function of effector Th17 cells in tissue inflammation.

Prognostic Significance of Asymptomatic Brain Natriuretic Peptide Elevation at Nephrology Referral in Patients with Chronic Kidney Disease.

BACKGROUND: It is unclear whether asymptomatic elevation of brain natriuretic peptide (BNP) is associated with cardiovascular events (CVEs) or heart failure (HF) in predialysis chronic kidney disease (CKD) patients. METHODS: We measured BNP in 482 asymptomatic predialysis patients with CKD stages 2-5 at nephrology referral between August 2004 and October 2010, and followed them prospectively to investigate the prognostic significance of BNP using Cox models and receiver operating characteristic (ROC) analyses. The primary composite end point was the time to death or the first nonfatal CVEs. Secondary end points included CVEs including sudden death, HF and all-cause death. RESULTS: The median age was 67 years (male, 67.4%; diabetic nephropathy, 33.4%), and estimated glomerular filtration rate was 20.1 mL/min/1.73 m2. The primary end point occurred in 92 patients. CVEs including sudden death, HF and all-cause death occurred in 66, 35, and 54 patients, respectively during a median follow-up period of 37.7 months. Multivariate analyses showed that BNP level was significantly associated with the primary end point (hazard ratio [HR] 1.241; 95% CI 1.020-1.511; p = 0.031), CVEs (HR 1.337; 95% CI 1.067-1.675; p = 0.012) and HF (HR 1.489; 95% CI 1.059-2.091; p = 0.022), but not associated with all-cause death (HR 1.081; 95% CI 0.829-1.410; p = 0.565). The ROC curves showed that the optimal predictive BNP levels for the primary end point, CVEs and HF were 92.5, 127.0, and 274.6 (pg/mL) respectively. CONCLUSION: Asymptomatic elevation of BNP is strongly predictive for CVEs and HF, which might help to integrate cardio-renal risk stratification in predialysis CKD patients.

Autoimmune Th17 Cells Induced Synovial Stromal and Innate Lymphoid Cell Secretion of the Cytokine GM-CSF to Initiate and Augment Autoimmune Arthritis.

Despite the importance of Th17 cells in autoimmune diseases, it remains unclear how they control other inflammatory cells in autoimmune tissue damage. Using a model of spontaneous autoimmune arthritis, we showed that arthritogenic Th17 cells stimulated fibroblast-like synoviocytes via interleukin-17 (IL-17) to secrete the cytokine GM-CSF and also expanded synovial-resident innate lymphoid cells (ILCs) in inflamed joints. Activated synovial ILCs, which expressed CD25, IL-33Ra, and TLR9, produced abundant GM-CSF upon stimulation by IL-2, IL-33, or CpG DNA. Loss of GM-CSF production by either ILCs or radio-resistant stromal cells prevented Th17 cell-mediated arthritis. GM-CSF production by Th17 cells augmented chronic inflammation but was dispensable for the initiation of arthritis. We showed that GM-CSF-producing ILCs were present in inflamed joints of rheumatoid arthritis patients. Thus, a cellular cascade of autoimmune Th17 cells, ILCs, and stromal cells, via IL-17 and GM-CSF, mediates chronic joint inflammation and can be a target for therapeutic intervention.

Development of a Formula to Correct Particle-Enhanced Turbidimetric Inhibition Immunoassay Values so That it More Precisely Reflects High-Performance Liquid Chromatography Values for Mycophenolic Acid.

BACKGROUND: Mycophenolic acid (MPA) concentration measured by homogeneous particle-enhanced turbidimetric inhibition immunoassay (PETINA) may be overestimated due to its cross-reactivity with pharmacologically inactive MPA glucuronide (MPAG), as well as other minor metabolites, accumulated with renal function impairment or co-administered cyclosporine A. In contrast, high-performance liquid chromatography (HPLC) is precise because it can exclude the cross-reactivity. In this study, we assumed HPLC values for MPA (HPLC-MPA) as a reference and aimed to develop a formula correcting PETINA values for MPA (PETINA-MPA) to more precisely reflect HPLC-MPA. METHODS: MPA trough concentrations were measured both by HPLC-UV and PETINA in 39 samples issued from 39 solid-organ transplant recipients. MPAG concentrations were also measured using HPLC UV assay. We determined the impacts of renal function and coadministered calcineurin inhibitor on concentrations of MPA and MPAG measured by HPLC. Then, we evaluated the difference between PETINA-MPA and HPLC-MPA. Finally, we develop a formula to reflect HPLC-MPA by using multilinear regression analysis. RESULTS: MPAG concentration was negatively correlated with estimated glomerular filtration rate (eGFR) (R2 = 0.376, P < 0.001), although MPA was not correlated with eGFR. There were no significant differences in MPA or MPAG concentrations per dose between the patients who were co-administered tacrolimus versus cyclosporine A. Finally, we developed the formulas to reflect HPLC-MPA:Formula 1: Estimated MPA concentration = 0.048 + 0.798 × PETINA-MPAFormula 2: Estimated MPA concentration = - 0.059 + 0.800 × PETINA-MPA + 0.002 × eGFRHowever, there was no significant improvement in the coefficient of determination with addition of eGFR in the formula, suggesting that HPLC-MPA can be well predicted by only 1 variable, PETINA-MPA. CONCLUSIONS: This study developed a formula so that PETINA-MPA can be corrected to more precisely reflect HPLC-MPA.