GLP-1 receptor agonists alleviate colonic inflammation by modulating intestinal microbiota and the function of group 3 innate lymphoid cells.

Glucagon-like peptide-1 receptor agonists (GLP-1RAs), which are drugs used for treating type 2 diabetes, have been reported to exert anti-inflammatory effects on inflammatory bowel disease (IBD), the mechanism of which remains elusive. Here, we report that GLP-1RAs ameliorate dextran sulfate sodium (DSS)-induced colitis in both wild-type and T/B-cell-deficient mice through modulating group 3 innate lymphoid cells (ILC3s), a subset of innate lymphoid cells that regulate intestinal immunity. GLP-1RAs promote IL-22 production by ILC3, and the protective effect of GLP-1RAs on DSS-induced colitis was abrogated in ILC3-deficient RORgtgfp/gfp mice. Furthermore, the treatment effect of GLP-RAs on colitis, as well as the generation of IL-22-producing ILC3s by GLP-RAs, is dependent on the gut microbiota. GLP-1RAs increase the abundance of Firmicutes and Proteobacteria in the gut, particularly beneficial bacteria such as Lactobacillus reuteri, and decrease the abundance of enteropathogenic Staphylococcus bacteria. The untargeted gas chromatography (GC)/liquid chromatography (LC)-mass spectrometry (MS) of faecal metabolites further revealed enrichment of N,N-dimethylsphingosine (DMS), an endogenous metabolite derived from sphingosine, in the GLP-1RA-treated group. Strikingly, DMS ameliorates colitis while promoting intestinal IL-22-producing ILC3s. Taken together, our findings show that GLP-1RAs exert a therapeutic effect on colitis possibly by regulating the microbiota-DMS-IL-22+ILC3 axis, highlighting the potential beneficial role of GLP-RAs in inflammatory intestinal disorders with diabetes complications.

Metagenomic next-generation sequencing reveals co-infection with Legionella pneumophila and Fusobacterium necrophorum in a patient with severe pneumonia: a case report.

BACKGROUND: Legionella pneumonia is one of the most severe types of atypical pneumonia, impairing multiple organ systems, posing a threat to life. Diagnosing Legionella pneumonia is challenging due to difficulties in culturing the bacteria and limitations in immunoassay sensitivity and specificity. CASE PRESENTATION: This paper reports a rare case of sepsis caused by combined infection with Legionella pneumophila and Fusobacterium necrophorum, leading to respiratory failure, acute kidney injury, acute liver injury, myocardial damage, and electrolyte disorders. In addition, we systematically reviewed literature on patients with combined Legionella infections, analyzing their clinical features, laboratory results and diagnosis. CONCLUSIONS: For pathogens that require prolonged incubation periods and are less sensitive to conventional culturing methods, metagenomic next-generation sequencing (mNGS) can be a powerful supplement to pathogen screening and plays a significant role in the auxiliary diagnosis of complex infectious diseases.

Quantitative detection of anti-PLA2R antibodies targeting different epitopes and its clinical application in primary membranous nephropathy.

OBJECTIVES: This study aimed to establish time-resolved fluorescence immunoassays to quantitatively detect the autoantibodies targeting different epitopes of M-type phospholipase A2 receptor (PLA2R) and evaluate its clinical application in primary membranous nephropathy (PMN). METHODS: PLA2R and its reactive epitope-specific IgG/IgG4 time-resolved fluorescence immunoassays (TRFIAs) were established using europium-labeled anti-human IgG/IgG4 antibodies, recombinant proteins, and patient serum. The levels of IgG/IgG4 targeting PLA2R and its epitopes in PMN patient serum were detected, and the relationship between epitope spreading of PLA2R and the severity of patients with PMN was evaluated. RESULTS: The TRFIAs established in this study could quantitatively detect PLA2R and its epitope-specific IgG and IgG4. Sera from 59 patients with PMN were subjected to detection using anti-PLA2R IgG and anti-PLA2R IgG4. Among them, 46 and 54 patients were found positive for PLA2R antibodies, respectively. Moreover, the levels of PLA2R antibodies were strongly correlated with the severity of patients with PMN. Patients who were detected to have two or more epitopes had more serious renal injury. CONCLUSIONS: PLA2R domain-specific IgG/IgG4 TRFIAs were established in this study, and detection with anti-PLA2R IgG4 could more sensitively screen the reactivity of patients to the PLA2R domain. Moreover, detection epitope spreading of PLA2R was confirmed which is related to the severity of patients with PMN.

Antagonizing EZH2 combined with vitamin D3 exerts a synergistic role in anti-fibrosis through bidirectional effects on hepatocytes and hepatic stellate cells.

BACKGROUND AND AIM: Whether vitamin D3 (VD3) supplementation is associated with improved liver fibrosis is controversial. METHODS: Liver fibrosis models were treated with VD3, active VD (1,25-OH2 Vitamin D3), or collaboration with GSK126 (Ezh2 inhibitor), respectively. Hepatic stellate cells (HSCs) were co-cultured with hepatocytes and then stimulated with TGF-ß. Autophagy of hepatocytes was determined after the intervention of 1,25-OH2 Vitamin D3 and GSK126. Also, the active status of HSCs and the mechanism with 1,25-OH2 Vitamin D3 and GSK126 intervention were detected. RESULTS: 1,25-OH2 Vitamin D3, but not VD3, is involved in anti-fibrosis and partially improves liver function, which might be associated with related enzymes and receptors (especially CYP2R1), leading to decreased of its biotransformation. GSK126 plays a synergistic role in anti-fibrosis. The co-culture system showed increased hepatocyte autophagy after HSCs activation. Supplementation with 1,25-OH2 Vitamin D3 or combined GSK126 reduced these effects. Further studies showed that 1,25-OH2 Vitamin D3 promoted H3K27 methylation of DKK1 promoter through VDR/Ezh2 due to the weakening for HSCs inhibitory signal. CONCLUSIONS: VD3 bioactive form 1,25-OH2 Vitamin D3 is responsible for the anti-fibrosis, which might have bidirectional effects on HSCs by regulating histone modification. The inhibitor of Ezh2 plays a synergistic role in this process.

Aberrant alteration of peripheral B lymphocyte subsets in hepatocellular carcinoma patients.

Although B lymphocytes are widely known to participate in the immune response, the conclusive roles of B lymphocyte subsets in the antitumor immune response have not yet been determined. Single-cell data from GEO datasets were first analyzed, and then a B cell flow cytometry panel was used to analyze the peripheral blood of 89 HCC patients and 33 healthy controls recruited to participate in our research. Patients with HCC had a higher frequency of B10 cells and a lower percentage of MZB cells than healthy controls. And the changes in B cell subsets might occur at an early stage. Moreover, the frequency of B10 cells decreased after surgery. Positively correlated with B10 cells, the elevated IL-10 level in HCC serum may be a new biomarker in HCC identification. For the first time, our results suggest that altered B cell subsets are associated with the development and prognosis of HCC. Increased B10 cell percentage and IL-10 in HCC patients suggest they might augment the development of liver tumors. Hence, B cell subsets and related cytokines may have predictive value in HCC patients and could be potential targets for immunotherapy in HCC.

Variation in vitamin D status in infants and children: a two-year cross-sectional study in Shanghai, China.

BACKGROUND: Vitamin D deficiency (VDD) is a public health problem. The variation in vitamin D status across regions and populations remains unclear, and there is a lack of consensus regarding the screening for VDD in individuals. METHODS: Children who visited the hospital from January 2019 to December 2020 were included in this study. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were measured using an enzyme-linked immunosorbent assay. The cutoffs for serum 25(OH)D concentrations to define deficiency, insufficiency, and sufficiency were < 20 ng/mL, 20-30 ng/mL, and ≥ 30 ng/mL, respectively. RESULTS: A total of 7285 children aged 0-11 years were assessed; the mean 25(OH)D level was 31.4 ng/mL, and the median 25(OH)D level was 30.7 (interquartile range 24.4, 37.5) ng/mL. The 25(OH)D level declined with age in clinical visiting children aged 0-11 years, but maintained a consistently high level in health examination children aged 4-11 years. The percentages of 25(OH)D < 20 ng/mL and 25(OH)D < 30 ng/mL were 10.0% and 43.8%, respectively. Higher percentages of VDD were found in clinical visiting children than in health examination children within the 6-11-year group (53.3% vs. 14.7%) and winter (44.3% vs. 15.4%). CONCLUSION: Low vitamin D status (deficiency and insufficiency) was more common in clinic-visiting children than in health examinations, especially in schoolchildren and in the winter. The study implies the positive effects of vitamin D assessments included in child health checkups to optimize vitamin D status.

Involvement of Qa-1/HLA-E-Restricted CD8+ T Cells in Anti-Microbe and Anti-Cancer Immunity as Well as in Immune Regulation.

The TCR-mediated recognition of self and microbial protein antigens by CD8+ T cells presented by the relatively nonvariable, class Ib MHC molecule, Qa-1 in mice and HLA-E in humans, is emerging as an important arm of the immune response. In this brief review, we will cover key examples of Qa1/HLA-E-restricted CD8+ T cells and their role in immunity against microbes and in cancer, but also as an important immunoregulatory pathway complementary to the FoxP3+CD4+ Treg. Although much remains to be learned, increased understanding of HLA-E-targeted immune responses can be potentially exploited in the development of broader and complementary immunotherapeutics against bacteria/viruses, tumors, and autoimmune diseases.

The Effects of Different Blood Sample Types on Quantitative Detection of Procalcitonin.

BACKGROUND: Procalcitonin (PCT) has been recommended and widely used for the prognosis, diagnosis, and monitoring of sepsis. Currently, a majority of PCT detection products are limited to using serum samples, which requires the tedious pre-treatment process, as well as a large sample volume for analysis. Hence, there is an increasing need to replace serum with plasma or whole blood samples. In this work, we evaluated the effects of different blood sample types on PCT quantitative detection by measuring PCT levels in clinically homogenous whole blood, plasma, and serum samples, in hope of extending the application of PCT detection in more sample types. METHODS: Ninety patients from Tong Ren Hospital of Shanghai Jiao Tong University, School of Medicine with different PCT levels volunteered for this study. Clinically homogenous samples, including EDTA- K2 anticoagulant whole blood, centrifuged serum and procoagulant plasma, were collected and analyzed using i-Reader S automatic immunoanalyzer and its supporting reagent kits. Passing and Bablok regression analysis, Bland-Altman plotting, and Kappa test were used for consistency analysis and the determination of consistency intensity, respectively. RESULTS: Correlation analysis showed that PCT concentrations measured from EDTA-K2 anticoagulated plasma samples had a good linear regression relationship with PCT from serum samples, with a slope of 0.8741, r = 0.958, p < 0.05. A similar correlation was observed between whole blood and serum, with a slope of 0.9234, r = 0.965, p < 0.05. A good correlation was found from the quantitative results of different sample types obtained from the same patient. In detail, PCT levels in EDTA-K2 anticoagulant whole blood and plasma are well correlated with that in the serum (r = 0.831, p < 0.05; r = 0.814, p < 0.05). There was no significant difference among different sample types (p > 0.05). Variation in PCT quantification induced by different sample types has no statistical influence on positive/negative decision (p > 0.05). Bland-Altman analysis for assessing PCT concentration agreement showed there was no outlier ratio between whole blood and plasma within the range of the detection system, as well as no outlier between serum and plasma. Kappa coefficient of PCT concentration between serum and homologous EDTA-K2 anticoagulated plasma was 0.8942 (p < 0.001), and for serum and homologous whole blood it was 0.6954 (p < 0.001). CONCLUSIONS: We concluded that quantitative PCT detection can be conducted in different sample types with good correlation and consistency, which means that it is feasible to replace serum samples with whole blood and/or plasma samples for PCT detection in clinical use. These findings reduce the sample volume and turnover time of PCT detection in clinical labs, greatly improving the process of PCT detection and promoting the application of PCT as an important inflammatory biomarker for disease diagnosis.

Distinct PLZF+CD8αα+ Unconventional T Cells Enriched in Liver Use a Cytotoxic Mechanism to Limit Autoimmunity.

Hepatic immune system is uniquely challenged to mount a controlled effector response to pathogens while maintaining tolerance to diet and microbial Ags. We have identified a novel population of innate-like, unconventional CD8αα+TCRαß+ T cells in naive mice and in human peripheral blood, called CD8αα Tunc, capable of controlling effector T cell responses. They are NK1.1+ (CD161+ in human), express NK-inhibitory receptors, and express the promyelocytic leukemia zinc finger (PLZF) transcription factor that distinguishes them from conventional CD8+ T cells. These cells display a cytotoxic phenotype and use a perforin-dependent mechanism to control Ag-induced or T cell-mediated autoimmune diseases. CD8αα Tunc are dependent upon IL-15/IL-2Rß signaling and PLZF for their development and/or survival. They are Foxp3-negative and their regulatory activity is associated with a functionally distinct Qa-1b-dependent population coexpressing CD11c and CD244. A polyclonal TCR repertoire, an activated/memory phenotype, and the presence of CD8αα Tunc in NKT- and in MAIT-deficient as well as in germ-free mice indicates that these cells recognize diverse self-protein Ags. Our studies reveal a distinct population of unconventional CD8+ T cells within the natural immune repertoire capable of controlling autoimmunity and also providing a new target for therapeutic intervention.

Circulating Cysteine Rich Protein 61 (Cyr61, CCN1) in Chinese Adults: Distribution and Reference Intervals.

BACKGROUND: The circulating levels of Cyr61 (also known as CCN1) may prove to have great clinical value in the diagnosis, monitoring and prognosis of many disorders in humans. However, the reference intervals (RIs) for this analyte in human subjects have not previously been well established. Therefore, establishing RIs and determining the distribution of circulating Cyr61 levels are very important for future clinical studies and could provide an orientation value for exploring its clinical usefulness. METHODS: The Cyr61 levels in 2,514 healthy Chinese Han subjects (1,250 males and 1,264 females, aged 18 - 88 years, recruited from 4 hospitals in Shanghai and Fujian) were measured with a sandwich ELISA (R&D Systems, USA). The RIs were determined in a manner consistent with the Clinical and Laboratory Standards Institute guidelines. RESULTS: The levels of serum Cyr61 showed a non-Gaussian distribution. A statistically significant difference was observed between the males and females such that the median level of Cyr61 in the males was significantly higher than that in the females. Furthermore, the Cyr61 levels significantly increased with age in the female group whereas no difference was observed among the different age groups among the males. The RIs for serum Cyr61 were 3.3 - 184 pg/mL and 5.0 - 182 pg/mL in females aged 18 - 45 and 46 - 88 years, respectively. The RI for serum Cyr61 was 4.0 - 198 pg/mL in the males. CONCLUSIONS: The RIs for serum Cyr61 were established among Chinese Han individuals. The effects of age and gender on the distribution characteristics of serum Cyr61 were studied, revealing that the RIs were gender and, in females, age-specific, which may suggest that a female hormone, estrogen plays a role in the regulation of Cyr61 expression in vivo.

Establishment of time-resolved fluoroimmunoassay of IgG4 based on magnetic microspheres.

BACKGROUND: The abnormal increase in serum IgG4 level is an important clinical symptom of IgG4-related disease (IgG4-RD), and the detection of serum IgG4 level is a powerful tool for the diagnosis of IgG4-RD. This study was conducted to establish a simple and rapid immunoassay for the determination of human serum IgG4 levels. METHODS: Based on the competition method, a novel immunoassay was established for the determination of human serum IgG4 using a combination of time-resolved fluoroimmunoassay (TRFIA) and magnetic microspheres. IgG4 was coupled with magnetic microspheres and competed with IgG4 in the samples to bind the Eu3+ -labeled anti-IgG4 antibody. The immunocomplex was separated and washed in a magnetic field, and the fluorescence counts were measured according to the number of dissociated europium ions. RESULTS: The analytical sensitivity of IgG4-TRFIA based on magnetic microspheres was 0.006 g/L, and the detection range was 0.006-20 g/L under optimal conditions. The precision, recovery, and specificity of this immunoassay were demonstrated to be acceptable. The clinical application of IgG4-TRFIA based on magnetic microspheres was evaluated and compared with that of immunonephelometry. The results showed that the two detection methods had a good correlation, with a correlation coefficient of .9871. CONCLUSION: IgG4-TRFIA based on magnetic microspheres has the advantages of high sensitivity, wide detection range, and short analysis time and has the potential to become a useful tool for the diagnosis of IgG4-RD.

Bartonella quintana type IV secretion effector BepE-induced selective autophagy by conjugation with K63 polyubiquitin chain.

Bartonella effector proteins (named Beps) are substrates of VirB type IV secretion system for translocation into host cells evolved in Bartonella spp. Among these, BepE has been shown to protect cells from fragmentation effects triggered by other Beps and to promote in vivo dissemination of bacteria from the dermal site of inoculation to the bloodstream. Bacterial pathogens secreted effectors to modulate the interplay with host autophagy, either to combat autophagy to escape its bactericidal effect or to exploit autophagy to benefit intracellular replication. Here, we reported a distinct phenotype that selective autophagy in host cells is activated as a countermeasure, to attack BepE via conjugation with K63 polyubiquitin chain on BepE. We found that ectopic expression of Bartonella quintana BepE specifically induced punctate structures that colocalised with an autophagy marker (LC3-II) in host cells, in addition to filopodia and membrane ruffle formation. Two tandemly arranged Bartonella Intracellular Delivery (BID) domains in the BepE C-terminus, where ubiquitination of sister pairs of lysine residues was confirmed, were essential to activate host cell autophagy. Multiple polyubiquitin chain linkages of K27, K29, K33, and K63 were found to be conjugated at sites of K222 and K365 on BepE, of which K63 polyubiquitination on BepE K365 determined the selective autophagy (p62/SQSTM1 positive autophagy) independent of the PI3K pathway. Colocalisation of BepE with LAMP1 confirmed the maturation of BepE-induced autophagosomes in which BepE were targeted for degradation. Moreover, host cells employed selective autophagy to counter-attack BepE to rescue cells from BepE-induced endocytosis deficiency.

IL-17-producing ST2+ group 2 innate lymphoid cells play a pathogenic role in lung inflammation.

BACKGROUND: IL-17 plays a pathogenic role in asthma. ST2- inflammatory group 2 innate lymphoid cells (ILC2s) driven by IL-25 can produce IL-17, whereas ST2+ natural ILC2s produce little IL-17. OBJECTIVE: We characterized ST2+IL-17+ ILC2s during lung inflammation and determined the pathogenesis and molecular regulation of ST2+IL-17+ ILC2s. METHODS: Lung inflammation was induced by papain or IL-33. IL-17 production by lung ILC2s from wild-type, Rag1-/-, Rorcgfp/gfp, and aryl hydrocarbon receptor (Ahr)-/- mice was examined by using flow cytometry. Bone marrow transfer experiments were performed to evaluate hematopoietic myeloid differentiation primary response gene-88 (MyD88) signaling in regulating IL-17 production by ILC2s. mRNA expression of IL-17 was analyzed in purified naive ILC2s treated with IL-33, leukotrienes, and inhibitors for nuclear factor of activated T cells, p38, c-Jun N-terminal kinase, or nuclear factor κ light-chain enhancer of activated B cells. The pathogenesis of IL-17+ ILC2s was determined by transferring wild-type or Il17-/- ILC2s to Rag2-/-Il2rg-/- mice, which further induced lung inflammation. Finally, expression of 106 ILC2 signature genes was compared between ST2+IL-17+ ILC2s and ST2+IL-17- ILC2s. RESULTS: Papain or IL-33 treatment boosted IL-17 production from ST2+ ILC2s (referred to by us as ILC217s) but not ST2- ILC2s. Ahr, but not retinoic acid receptor-related orphan receptor γt, facilitated the production of IL-17 by ILC217s. The hematopoietic compartment of MyD88 signaling is essential for ILC217 induction. IL-33 works in synergy with leukotrienes, which signal through nuclear factor of activated T-cell activation to promote IL-17 in ILC217s. Il17-/- ILC2s were less pathogenic in lung inflammation. ILC217s concomitantly expressed IL-5 and IL-13 but expressed little GM-CSF. CONCLUSION: During lung inflammation, IL-33 and leukotrienes synergistically induce ILC217s. ILC217s are a highly pathogenic and unexpected source for IL-17 in lung inflammation.

Phospholipase A2 Receptor Antibody IgG4 Subclass Improves Sensitivity and Specificity in the Diagnosis of Idiopathic Membranous Nephropathy.

AIMS: The aim of this study was to develop a new method for detecting anti-phospholipase A2 receptor-IgG4 to improve the sensitivity and specificity in the diagnosis of idiopathic membranous nephropathy (IMN). METHODS: A highly sensitive quantitative assay was developed for the detection of serum anti-phospholipase A2 receptor-IgG4 with europium chelation by time-resolved fluoroimmunoassay (TRFIA), and a mouse anti-human IgG4 tracer was prepared using europium chelation for detection. The specificity and sensitivity of anti-phospholipase A2 receptor-IgG4 in the diagnosis of IMN were further assessed in patients with different kidney diseases. RESULTS: The detection limit of anti-PLA2R-IgG4 was 0.69 ng/mL. The measurement range of anti-PLA2R-IgG4 TRFIA was 0.69-2,500 ng/mL. Mean serum anti-PLA2R-IgG4 was 21.27 ± 15.15 ng/mL in 45 healthy volunteers, 31.08 ± 18.17 ng/mL in 29 IgA nephropathy patients, 49.10 ± 34.32 ng/mL in 8 lupus nephropathy patients, and 10,324.11 ± 17,030.40 ng/mL in 30 IMN patients. The anti-PLA2R-IgG4 cutoff concentration was >161.2 ng/mL with the sensitivity of 90.0% and specificity of 100% in the diagnosis of IMN. However, the cutoff for other kidney diseases was lower than 161.2 ng/mL. CONCLUSION: The serum anti-phospholipase A2 receptor IgG4 detected with the method developed in this study has higher sensitivity and higher specificity than total IgG in the diagnosis of IMN.

Chlamydia trachomatis, Ureaplasma urealyticum and Neisseria gonorrhoeae among Chinese women with urinary tract infections in Shanghai: A community-based cross-sectional study.

AIM: This study explored chlamydia trachomatis (CT), ureaplasma urealyticum (UU) and/or neisseria gonorrhoeae (NG) in 5893 women with urinary tract infections (UTIs) in Shanghai. METHODS: From January 2009 to December 2014, 5893 women with UTIs in Shanghai were selected to undergo CT, UU and NG detection. Baseline characteristics including age, education level, occupation, reproductive history, sexual behavior and contraceptive method were obtained for epidemiological analysis. RESULTS: The total CT, UU and/or NG infection rate in the urine samples of 5893 patients was 50.69% (2987/5893), while the infection rate in vaginal secretion samples was 56.22% (3313/5893). The two detection methods were consistent. Patients aged 21-30, service personnel and unemployed persons had the highest rates of CT, UU and/or NG infection, while patients with higher education levels exhibited lower rates. As the number of previous pregnancies, natural births, abortions, sexual partners and the frequency of sexual intercourse increased, the rates of CT, UU and/or NG infection were elevated. Sexual intercourse during the menstruation period, a lack of cleaning before sexual intercourse and the use of intrauterine devices could all lead to an increased rate of CT, UU and/or NG infection. CONCLUSIONS: These data revealed that the rate of CT, UU and/or NG infection may be associated with age, education level, occupation, reproductive history, sexual behavior and type of contraceptive method in female patients with UTI in Shanghai.

Autoimmune Responses to Exosomes and Candidate Antigens Contribute to Type 1 Diabetes in Non-Obese Diabetic Mice.

PURPOSE OF REVIEW: The initial autoimmune trigger of type 1 diabetes (T1D) remains unclear. In non-obese diabetic (NOD) mice, islet inflammation starts early in life, suggesting the presence of an endogenous trigger for the spontaneous autoimmune response in this T1D mouse model. In this review, we argue that abnormal release of exosomes might be the trigger of the early inflammatory and autoimmune responses in the islets. RECENT FINDINGS: Exosomes are nano-sized membrane complexes that are secreted by cells following fusion of late endosomes and/or multivesicular bodies with the plasma membrane. They are known extracellular messengers, communicating among neighboring cells via transporting large molecules from parent cells to recipient cells. Recent evidence demonstrates that these extracellular vesicles can modulate immune responses. It has been shown that insulinoma and islet mesenchymal stem cell-released exosomes are potent immune stimuli that can induce autoreactive B and T cells. Searching for candidate antigens in the exosomes identified endogenous retrovirus (ERV) Env and Gag antigens, which are homologous to an endogenous murine leukemia retrovirus. Autoantibodies and autoreactive T cells spontaneously developed in NOD mice can react to these retroviral antigens. More importantly, expression of the retroviral antigens in the islet mesenchymal stem cells is associated with disease susceptibility, and the expression is restricted to T1D-susceptible but not resistant mouse strains. Exosomes are novel autoimmune targets, carrying autoantigens that can stimulate innate and adaptive immune responses. An abnormal or excess release of exosomes, particularly those ones containing endogenous retroviral antigens might be responsible for triggering tissue-specific inflammatory and autoimmune responses.

Urinary exosomes as a novel biomarker for evaluation of α-lipoic acid's protective effect in early diabetic nephropathy.

BACKGROUND: Long-term administration of α-lipoic acid (α-LA) is proved to ameliorate renal impairment. Herein we assessed serum, urinary biomarkers and vascular endothelium function to evaluate its short-period therapeutic effect and identify novel biomarkers for diabetic nephropathy (DN). METHODS: Sixty-two microalbuminuria-stage DN patients were randomly divided into two groups and received the following treatment for 8 weeks: (1) routine treatment(DM group); (2) routine treatment with 600 mg/d α-lipoic acid intravenously (α-LA group). Another total of 21 patients were recruited for the second-stage study and randomly divided into two groups: normoalbuminuria (UAER <30 mg/24 h) and microalbuminuria (UAER from 30-300 mg/24 h). RESULTS: With α-LA treatment, urinary albumin excretion rates (UAER), serum creatinine (SCr) and malonaldehyde (MDA) declined significantly, whereas plasma superoxide dismutase (SOD)activity increased and endothelium-dependent flow mediated vasodilation (FMD) flexibility improved dramatically. Furthermore, the improvement of FMD showed positive correlation with the variation in MDA and SOD as well (r values are .516 and .435, P<.01 and P<.05, respectively). In contrast, these markers have no significant difference in the DM group with routine treatment. Notably, the CD63 expressing of exosomes in urine was found higher in the normoalbuminuria patients compared with those in microalbuminuria, parallelly only declined markedly after α-LA administration in normoalbuminuria patients. CONCLUSION: In summary, we emphasize short-term α-LA could protect the kidney in the early DN against general oxidative stress, particularly the urinary CD63-positive exosome could be a potential sensitive and therapeutic indicator.

Cyr61 participates in the pathogenesis of rheumatoid arthritis via promoting MMP-3 expression by fibroblast-like synoviocytes.

OBJECTIVES: The aim of this study was to investigate the effect and potential mechanism of Cysteine-rich 61 (Cyr61) on stimulating MMP-3 expression by fibroblast-like synoviocytes (FLS) from rheumatoid arthritis (RA) patients. METHODS: Primarily cultured RA FLS were treated with exogenous Cyr61 protein or Cyr61-siRNA, then, MMP-3 expression was analyzed by real-time PCR, western blotting and ELISA. Signal transduction pathways in Cyr61-induced MMP-3 production were examined by real-time PCR, western blotting, confocal microscopy, luciferase reporter assay. Mice with collagen-induced arthritis (CIA) were treated with anti-Cyr61 monoclonal antibodies (mAb), or IgG1 as control and MMP-3 in the joint was detected by IHC, real-time PCR and western blotting. RESULTS: High expressed MMP-3 and Cyr61 were positively correlated in RA ST; Cyr61 stimulated MMP-3 production in FLS of RA patients in an IL-1ß and TNF-α independent manner. Cyr61 induced MMP-3 could further enhance the invasive ability of RA FLS. Mechanistically, we found that Cyr61 promoted MMP-3 production via the P38, JNK-dependent AP-1 signaling pathway. Blockage of Cyr61 function with monoclonal antibody could decrease MMP-3 expression in the joints of CIA mice. CONCLUSION: This study provides new evidence that Cyr61 participates in RA pathogenesis not only as a pro-inflammatory factor but also plays a key role in bone erosion via promoting MMP-3 expression. We suggest that targeting of Cyr61 may represent a potential strategy in RA treatment.

Inhibition of type I natural killer T cells by retinoids or following sulfatide-mediated activation of type II natural killer T cells attenuates alcoholic liver disease in mice.

UNLABELLED: Innate immune mechanisms leading to liver injury subsequent to chronic alcohol ingestion are poorly understood. Natural killer T (NKT) cells, enriched in the liver and comprised of at least two distinct subsets, type I and II, recognize different lipid antigens presented by CD1d molecules. We have investigated whether differential activation of NKT cell subsets orchestrates inflammatory events leading to alcoholic liver disease (ALD). We found that after chronic plus binge feeding of Lieber-DeCarli liquid diet in male C57BL/6 mice, type I, but not type II, NKT cells are activated, leading to recruitment of inflammatory Gr-1(high) CD11b(+) cells into the liver. A central finding is that liver injury after alcohol feeding is dependent upon type I NKT cells. Thus, liver injury is significantly inhibited in Jα18(-/-) mice deficient in type I NKT cells as well as after their inactivation by sulfatide-mediated activation of type II NKT cells. Furthermore, we have identified a novel pathway involving all-trans retinoic acid (ATRA) and its receptor (RARγ) signaling that inhibits type I NKT cells and, consequently, ALD. A semiquantitative polymerase chain reaction analysis of hepatic gene expression of some of the key proinflammatory molecules shared in human disease indicated that their up-regulation in ALD is dependent upon type I NKT cells. CONCLUSIONS: Type I, but not type II, NKT cells become activated after alcohol feeding. Type I NKT cell-induced inflammation and neutrophil recruitment results in liver tissue damage whereas type II NKT cells protect from injury in ALD. Inhibition of type I NKT cells by retinoids or by sulfatide prevents ALD. Given that the CD1d pathway is highly conserved between mice and humans, NKT cell subsets might be targeted for potential therapeutic intervention in ALD.

Identification of inflammatory mediators in patients with rhegmatogenous retinal detachment associated with choroidal detachment.

PURPOSE: To investigate the expression profile of intravitreous cytokines, chemokines, and growth factors in patients with rhegmatogenous retinal detachment associated with choroidal detachment (RRDCD) in comparison with patients with only rhegmatogenous retinal detachment (RRD). METHODS: Twenty RRDCD patients and 30 RRD patients were included in this case-control study. A multiplex bead-based immunoassay was performed to determine the expression of a wide range of 29 inflammatory mediators in undiluted vitreous from the patients. Data were analyzed using the Mann-Whitney U-test for nonparametric values and multivariate logistic regression analysis. RESULTS: Compared with the patients with RRD, intravitreous inflammatory mediators, including migration inhibitor factor (MIF), interleukin-6 (IL-6), CCL4, CCL11, CCL17, CCL19, CCL22, CXCL9, CXCL8, soluble inter-cellular adhesion molecule 1 (sICAM-1), transforming growth factor ß3 (TGF-ß3), and platelet-derived growth factor AA (PDGF-AA), were upregulated in patients with RRDCD. After calibrating the factors duration of detachment, preoperative proliferative vitreoretinopathy grade, and presence or absence of macular hole, the PDGF-AA concentrations were not significantly different according to the multivariate logistic regression analysis. MIF and sICAM-1 markers were significantly different between the two groups and represented a forward stepwise logistic regression trend. CONCLUSIONS: This is the first report to use multiplex bead analysis to investigate inflammatory mediators related to RRDCD. We proposed that the upregulated expression of these mediators may be involved in the inflammation process of RRDCD and that regulation of their expression may be potentially therapeutic by altering local inflammation.