Glucose Requirement of Antigen-Specific Autoreactive B Cells and CD4+ T Cells.

The activation of lymphocytes in patients with lupus and in mouse models of the disease is coupled with an increased cellular metabolism in which glucose plays a major role. The pharmacological inhibition of glycolysis with 2-deoxy-d-glucose (2DG) reversed the expansion of follicular helper CD4+ T cells and germinal center B cells in lupus-prone mice, as well as the production of autoantibodies. The response of foreign Ags was however not affected by 2DG in these mice, suggesting that B and CD4+ T cell activation by autoantigens is uniquely sensitive to glycolysis. In this study, we tested this hypothesis with monoclonal B cells and CD4+ T cells specific for lupus-relevant autoantigens. AM14 Vκ8R (AM14) transgenic B cells are activated by IgG2a/chromatin immune complexes and they can receive cognate help from chromatin-specific 13C2 CD4+ T cells. We showed that activation of AM14 B cells by their cognate Ag PL2-3 induced glycolysis, and that the inhibition of glycolysis reduced their activation and differentiation into Ab-forming cells, in the absence or presence of T cell help. The dependency of autoreactive B cells on glycolysis is in sharp contrast with the previously reported dependency of 4-hydroxy-3-nitrophenyl acetyl-specific B cells on fatty acid oxidation. Contrary to AM14 B cells, the activation and differentiation of 13C2 T cells into follicular helper CD4+ T cells was not altered by 2DG, which differs from polyclonal CD4+ T cells from lupus-prone mice. These results further define the role of glycolysis in the production of lupus autoantibodies and demonstrate the need to evaluate the metabolic requirements of Ag-specific B and T cells.

Pharmacologically Inferred Glycolysis and Glutaminolysis Requirement of B Cells in Lupus-Prone Mice.

Several studies have shown an enhanced metabolism in the CD4+ T cells of lupus patients and lupus-prone mice. Little is known about the metabolism of B cells in lupus. In this study, we compared the metabolism of B cells between lupus-prone B6.Sle1.Sle2.Sle3 triple-congenic mice and C57BL/6 controls at steady state relative to autoantibody production, as well as during T cell-dependent (TD) and T cell-independent (TI) immunizations. Starting before the onset of autoimmunity, B cells from triple-congenic mice showed an elevated glycolysis and mitochondrial respiration, which were normalized in vivo by inhibiting glycolysis with a 2-deoxy-d-glucose (2DG) treatment. 2DG greatly reduced the production of TI-Ag-specific Abs, but showed minimal effect with TD-Ags. In contrast, the inhibition of glutaminolysis with 6-diazo-5-oxo-l-norleucine had a greater effect on TD than TI-Ag-specific Abs in both strains. Analysis of the TI and TD responses in purified B cells in vitro suggests, however, that the glutaminolysis requirement is not B cell-intrinsic. Thus, B cells have a greater requirement for glycolysis in TI than TD responses, as inferred from pharmacological interventions. B cells from lupus-prone and control mice have different intrinsic metabolic requirements or different responses toward 2DG and 6-diazo-5-oxo-l-norleucine, which mirrors our previous results obtained with follicular Th cells. Overall, these results predict that targeting glucose metabolism may provide an effective therapeutic approach for systemic autoimmunity by eliminating both autoreactive follicular Th and B cells, although it may also impair TI responses.

Metabolic determinants of lupus pathogenesis.

The metabolism of healthy murine and more recently human immune cells has been investigated with an increasing amount of details. These studies have revealed the challenges presented by immune cells to respond rapidly to a wide variety of triggers by adjusting the amount, type, and utilization of the nutrients they import. A concept has emerged that cellular metabolic programs regulate the size of the immune response and the plasticity of its effector functions. This has generated a lot of enthusiasm with the prediction that cellular metabolism could be manipulated to either enhance or limit an immune response. In support of this hypothesis, studies in animal models as well as human subjects have shown that the dysregulation of the immune system in autoimmune diseases is associated with a skewing of the immunometabolic programs. These studies have been mostly conducted on autoimmune CD4+ T cells, with the metabolism of other immune cells in autoimmune settings still being understudied. Here we discuss systemic metabolism as well as cellular immunometabolism as novel tools to decipher fundamental mechanisms of autoimmunity. We review the contribution of each major metabolic pathway to autoimmune diseases, with a focus on systemic lupus erythematosus (SLE), with the relevant translational opportunities, existing or predicted from results obtained with healthy immune cells. Finally, we review how targeting metabolic programs may present novel therapeutic venues.

Three-port approach vs conventional laparoscopic radical cystectomy with orthotopic neobladder: a single-center retrospective study.

BACKGROUND: This study aimed to compare the clinical outcomes of patients who underwent three-port laparoscopic radical cystectomy (LRC) with orthotopic neobladder (ONB) and traditional five-port method. METHODS: From January 2017 to November 2020, 100 patients underwent LRC + ONB at a third-level grade A hospital. RESULTS: Our study included 55 patients who underwent three-port LRC and 45 patients who underwent the five-port method. There were no significant differences in perioperative data such as operation time (253.00 ± 43.89 vs. 259.07 ± 52.31 min, P = 0.530), estimated blood loss (EBL)(97.64 ± 59.44 vs. 106.67 ± 55.35 min, P = 0.438), day to flatus (2.25 ± 1.49 vs. 2.76 ± 1.77 days, P = 0.128), day to regular diet (7.07 ± 2.99 vs. 7.96 ± 3.32 days, P = 0.165), day to pelvic drain removal (9.58 ± 3.25 vs. 10.53 ± 3.80 days, P = 0.180), and hospital stay after operation (11.62 ± 3.72 vs. 11.84 ± 4.37 days, P = 0.780) between the two groups. The only significant difference was in the treatment cost (P = 0.035). Similarly, postoperative complications, quality of life, and tumor outcomes were not significantly different between the two groups (P > 0.05). CONCLUSIONS: The three-port method is safe and feasible for patients suitable for traditional five-port LRC with an orthotopic neobladder.

Attaining treat-to-target endpoints with metformin in lupus patients: a pooled analysis.

OBJECTIVES: Low disease activity status and remission are crucial treat-to-target (T2T) endpoints in systemic lupus erythematosus (SLE). To evaluate the efficacy of metformin add-on in attaining T2T among Chinese patients with mild-to-moderate lupus, a post-hoc analysis combining our previous two randomised trials was carried out. METHODS: Data from the open-labeled proof-of-concept trial (ChiCTR-TRC-12002419) and placebo-controlled trial (NCT02741960) were integrated together. Disease flares were compared between patients attaining T2T or not at baseline. The efficacy of metformin versus placebo/nil add-on to standard therapy in SLE patients who did not meet the T2T criteria at baseline was evaluated in terms of attaining T2T at 12-month follow-up. RESULTS: Of 253 SLE patients, 43.8% (n=89) attained T2T at baseline. During the 12 months, 15 patients flared in the T2T group, which was significantly lower than that in the non-T2T group (16.9% vs. 36.0%, p=0.001). For 164 patients who did not meet the T2T criteria at entry, 59.0% and 43.6% of the 78 patients taking metformin in this population attained the lupus low disease activity status (LLDAS) and remission endpoints at last visit, respectively, as compared to 37.2% and 24.4% of the 86 patients in the placebo/nil group (LLDAS p=0.008; remission p=0.013). Over time, metformin helped patients achieving T2T earlier and maintain longer T2T duration over placebo/nil (LLDAS duration: 44.9% vs. 26.4%, p=0.002; remission duration:19.1% vs. 10.7%, p=0.014). CONCLUSIONS: This post-hoc analysis suggested that metformin might be an adjuvant therapy in achieving treat-to-target in SLE patients.

D-mannose ameliorates autoimmune phenotypes in mouse models of lupus.

BACKGROUND: Systemic lupus erythematosus is an autoimmune disease characterized by an overproduction of autoantibodies resulting from dysregulation in multiple immune cell types. D-mannose is a C- 2 epimer of glucose that exhibits immunoregulatory effects in models of autoimmune diseases, such as type 1 diabetes, induced rheumatoid arthritis, and airway inflammation. This study was conducted to evaluate the efficacy of D-mannose treatment in mouse models of lupus. RESULTS: Firstly, the effect of D-Mannose was evaluated by flow cytometry on the in vitro activation of non-autoimmune C57BL/6 (B6) bone marrow-derived dendritic cells (BMDCs) and their ability to induce antigen-specific CD4+ T cell proliferation and activation. D-mannose inhibited the maturation of BMDCs and their induction of antigen-specific T cell proliferation and activation. In vivo, D-mannose increased the frequency of Foxp3+ regulatory T cells in unmanipulated B6 mice. To assess the effect of D-mannose in mouse models of lupus, we used the graft-versus-host disease (cGVHD) induced model and the B6.lpr spontaneous model. In the cGVHD model, D-mannose treatment decreased autoantibody production, with a concomitant reduction of the frequency of effector memory and follicular helper T cells as well as germinal center B cells and plasma cells. These results were partially validated in the B6.lpr model of spontaneous lupus. CONCLUSION: Overall, our results suggest that D-mannose ameliorates autoimmune activation in models of lupus, at least partially due to its expansion of Treg cells, the induction of immature conventional dendritic cells and the downregulation of effector T cells activation. D-Mannose showed however a weaker immunomodulatory effect in lupus than in other autoimmune diseases.

Acetylation Rather than H50Q Mutation Impacts the Kinetics of Cu(II) Binding to α-Synuclein.

The interaction between α-synuclein (αSyn) and Cu2+ has been suggested to be closely linked to brain copper homeostasis. Disruption of copper levels could induce misfolding and aggregation of αSyn, and thus contribute to the progression of Parkinson's disease (PD). Understanding the molecular mechanism of αSyn-Cu2+ interaction is important and controversies in Cu2+ coordination geometry with αSyn still exists. Herein, we find that the pathological H50Q mutation has no impact on the kinetics of Cu2+ binding to the high-affinity site of wild type αSyn (WT-αSyn), indicating the non-involvement of His50 in high-affinity Cu2+ binding to WT-αSyn. In contrast, the physiological N-terminally acetylated αSyn (NAc-αSyn) displays several orders of magnitude weaker Cu2+ binding affinity than WT-αSyn. Cu2+ coordination mode to NAc-αSyn has also been proposed based on EPR spectrum. In addition, we find that Cu2+ coordinated WT-αSyn is reduction-active in the presence of GSH, but essentially inactive towards ascorbate. Our work provides new insights into αSyn-Cu2+ interaction, which may help understand the multifaceted normal functions of αSyn as well as pathological consequences of αSyn aggregation.

Acetylation Rather than H50Q Mutation Impacts the Kinetics of Cu(II) Binding to α-Synuclein.

The front cover artwork is provided by the group of Liming Ying at Imperial College London. The image shows that N-terminal acetylation of α-synuclein shifts the binding from the N-terminus to His50 and significantly slows down the binding reaction. Read the full text of the Article at 10.1002/cphc.202100651.

Redox Kinetics of the Amyloid-ß-Cu Complex and Its Biological Implications.

The ability of the amyloid-ß peptide to bind to redox active metals and act as a source of radical damage in Alzheimer's disease has been largely accepted as contributing to the disease's pathogenesis. However, a kinetic understanding of the molecular mechanism, which underpins this radical generation, has yet to be reported. Here we use a sensitive fluorescence approach, which reports on the oxidation state of the metal bound to the amyloid-ß peptide and can therefore shed light on the redox kinetics. We confirm that the redox goes via a low populated, reactive intermediate and that the reaction proceeds via the Component I coordination environment rather than Component II. We also show that while the reduction step readily occurs (on the 10 ms time scale) it is the oxidation step that is rate-limiting for redox cycling.

Kinetics of the Interactions between Copper and Amyloid-ß with FAD Mutations and Phosphorylation at the N†terminus.

Mutations and post-translational modifications of amyloid-ß (Aß) peptide in its N terminus have been shown to increase fibril formation, yet the molecular mechanism is not clear. Here we investigated the kinetics of the interactions of copper with two Aß peptides containing Familial Alzheimer's disease (FAD) mutations (English (H6R) and Tottori (D7N)), as well as with Aß peptide phosphorylated at serine 8 (pS8). All three peptides bind to copper with a similar rate as the wild-type (wt). The dissociation rates follow the order pS8>H6R>wt>D7N; the interconversion between the two coordinating species occurs 50 % faster for H6R and pS8, whereas D7N had only a negligible effect. Interestingly, the rate of ternary complex (copper-bridged heterodimer) formation for the modified peptides was significantly faster than that for wt, thus leading us to propose that FAD and sporadic AD might share a kinetic origin for the enhanced oligomerisation of Aß.

Novel Isolating Approaches to Circulating Tumor Cell Enrichment Based on Microfluidics: A Review.

Circulating tumor cells (CTCs), derived from the primary tumor and carrying genetic information, contribute significantly to the process of tumor metastasis. The analysis and detection of CTCs can be used to assess the prognosis and treatment response in patients with tumors, as well as to help study the metastatic mechanisms of tumors and the development of new drugs. Since CTCs are very rare in the blood, it is a challenging problem to enrich CTCs efficiently. In this paper, we provide a comprehensive overview of microfluidics-based enrichment devices for CTCs in recent years. We explore in detail the methods of enrichment based on the physical or biological properties of CTCs; among them, physical properties cover factors such as size, density, and dielectric properties, while biological properties are mainly related to tumor-specific markers on the surface of CTCs. In addition, we provide an in-depth description of the methods for enrichment of single CTCs and illustrate the importance of single CTCs for performing tumor analyses. Future research will focus on aspects such as improving the separation efficiency, reducing costs, and increasing the detection sensitivity and accuracy.

Interplay between Copper, Phosphatidylserine, and α-Synuclein Suggests a Link between Copper Homeostasis and Synaptic Vesicle Cycling.

Copper homeostasis is critical to the functioning of the brain, and its breakdown is linked with many brain diseases. Copper is also known to interact with the negatively charged lipid, phosphatidylserine (PS), as well as α-synuclein, an aggregation-prone protein enriched in the synapse, which plays a role in synaptic vesicle docking and fusion. However, the interplay between copper, PS lipid, and α-synuclein is not known. Herein, we report a detailed and predominantly kinetic study of the interactions among these three components pertinent to copper homeostasis and neurotransmission. We found that synaptic vesicle-mimicking small unilamellar vesicles (SUVs) can sequester any excess free Cu2+ within milliseconds, and bound Cu2+ on SUVs can be reduced to Cu+ by GSH at a nearly constant rate under physiological conditions. Moreover, we revealed that SUV-bound Cu2+ does not affect the binding between wild-type α-synuclein and SUVs but affect that between N-terminal acetylated α-synuclein and SUVs. In contrast, Cu2+ can effectively displace both types of α-synuclein from the vesicles. Our results suggest that synaptic vesicles may mediate copper transfer in the brain, while copper could participate in synaptic vesicle docking to the plasma membrane via its regulation of the interaction between α-synuclein and synaptic vesicle.

Policy choices for China to reduce carbon emissions in coping with extreme weather: Applying a dynamic two-stage undesirable non-radial directional distance function.

China is the world's largest carbon emitter and also one of many countries most affected by extreme weather. Although its government has set carbon reduction targets, the public has not established a connection between carbon reduction and coping with extreme weather. This study aims to help establish the above connection and applies a dynamic two-stage undesirable non-radial directional distance function to evaluate energy performance in the first stage while establishing CO2 emissions as a link to evaluate coping with extreme weather performance in the second stage. From empirical results, the average efficiency of 30 provinces in China in coping with extreme weather from 2011 to 2020 is only 0.484, or far lower than the energy efficiency value of 0.709. Based on the differences in performance between the two stages and the changing trends in the room for improvement of CO2 emissions, this study proposes policy options to promote the participation of the entire society in the emission reduction process.

A bionic mimosa soft robot based on a multi-responsive PNIPAM-PEGDA hydrogel composition.

Deformation plays a vital role in the survival of natural organisms. One example is that plants deform themselves to face the sun for sufficient sunlight exposure, which allows them to produce nutrients through photosynthesis. Drawing inspiration from nature, researchers have been exploring the development of 3D deformable materials. However, the traditional approach to manufacturing deformable hydrogels relies on complex technology, which limits their potential applications. In this study, we simulate the stress variations observed in the plant tissue to create a 3D structure from a 2D material. Using UV curing technology, we create a single-layer poly(N-isopropylacrylamide) hydrogel sheet with microchannels that exhibit distinct swelling rates when subjected to stimulation. After a two-step curing process, we produce a poly(N-isopropylacrylamide)-polyethylene glycol diacrylatedouble-layer structure that can be manipulated to change its shape by controlling the light and solvent content. Based on the double-layer structure, we fabricate a dual-response driven bionic mimosa robot that can perform a variety of functions. This soft robot can not only reversibly change its shape but also maintain a specific shape without continuous stimulation. Its capacity for reversible deformation, resulting from internal stress, presents promising application prospects in the biomedical and soft robotics domain. This study delivers an insightful framework for the development of programmable soft materials.

Recent Advances in Microrobots Powered by Multi-Physics Field for Biomedical and Environmental Applications.

Microrobots powered by multi-physics fields are becoming a hotspot for micro-nano manufacturing. Due to the small size of microrobots, they can easily enter small spaces that are difficult for ordinary robots to reach and perform a variety of special tasks. This gives microrobots a broad application prospect in many fields. This paper describes the materials, structures, and driving principles of microrobots in detail and analyzes the advantages and limitations of their driving methods in depth. In addition, the paper discusses the detailed categorization of the action forms of microrobots and explores their diversified motion modes and their applicable scenarios. Finally, the article highlights the wide range of applications of microrobots in the fields of biomedicine and environmental protection, emphasizing their great potential for solving real-world problems and advancing scientific progress.

Clinical characteristics of testicular torsion and factors influencing testicular salvage in children: A 12-year study in tertiary center.

BACKGROUND: Testicular torsion is the most common acute scrotum worldwide and mainly occurs in children and adolescents. Studies have demonstrated that the duration of symptoms and torsion grade lead to different outcomes in children diagnosed with testicular torsion. AIM: To predict the possibility of testicular salvage (TS) in patients with testicular torsion in a tertiary center. METHODS: We reviewed the charts of 75 pediatric patients with acute testicular torsion during a 12-year period from November 2011 to July 2023 at the Suzhou Hospital of Anhui Medical University. Univariate and multivariate logistic regression analyses were used to determine independent predictors of testicular torsion. The data included clinical findings, physical examinations, laboratory data, color Doppler ultrasound findings, operating results, age, presenting institution status, and follow-up results. RESULTS: Our study included 75 patients. TS was possible in 57.3% of all patients; testicular torsion occurred mostly in winter, and teenagers aged 11-15 years old accounted for 60%. Univariate logistic regression analyses revealed that younger age (P = 0.09), body mass index (P = 0.004), torsion angle (P = 0.013), red blood cell count (P = 0.03), neutrophil-to-lymphocyte ratio (P = 0.009), and initial presenting institution (P < 0.001) were associated with orchiectomy. In multivariate analysis, only the initial presenting institution predicted TS (P < 0.05). CONCLUSION: The initial presenting institution has a predictive value for predicting TS in patients with testicular torsion. Children with scrotal pain should be admitted to a tertiary hospital as soon as possible.

Exploring the crosstalk of immune cells: The impact of dysregulated RUNX family genes in kidney renal clear cell carcinoma.

Background: Abnormally expressed Runt-associated transcription factor (RUNX) family has been reported in multiple tumors. Nevertheless, the immunological role of RUNX family in kidney renal clear cell carcinoma (KIRC) remains unknown. Methods: We studied the RNA-seq data regarding tumor and healthy subjects from several public databases in detail for evaluating the prognostic and immunological functions owned by three RUNX genes in cancer patients. Quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemical (IHC) staining served for detecting their expressions in tumor and normal samples. Results: We observed that KIRC patients presented high expressions of RUNX1, RUNX2, and RUNX3. The expressions of three genes were validated by qRT-PCR, which was same as bioinformatical results. Prognostic analysis indicated that the overexpression of RUNX1 and RUNX2 negatively affects the outcomes in patients with KIRC. Related functional predictions indicated that the RUNXs and co-expression genes were significantly related to the immune response pathway. Moreover, three RUNX members were associated with immune infiltration cells and their related gene markers. The expression of RUNX family in several immune cells is positively or negatively correlated, and its dysregulation is obviously associated with the differential distribution of immune cells. RUNX family genes were abnormally expressed in KIRC patients, and were closely related to the crosstalk of immune cells. Conclusions: Our findings may help to understand the pathogenesis and immunologic roles of the RUNX family in KIRC patients from new perspectives.

Anti-synthetase syndrome is associated with a higher risk of hospitalization among patients with idiopathic inflammatory myopathy and COVID-19.

Background: Data with fine granularity about COVID-19-related outcomes and risk factors were still limited in the idiopathic inflammatory myopathies (IIMs) population. This study aimed to investigate clinical factors associated with hospitalized and severe COVID-19 in patients with IIMs, particularly those gauged by myositis-specific antibodies. Methods: This retrospective cohort study was conducted in the Renji IIM cohort in Shanghai, China, under an upsurge of SARS-CoV-2 omicron variant infections from December 2022 to January 2023. Clinical data were collected and analyzed by multivariable logistic regression to determine risk factors. High-dimensional flow cytometry analysis was performed to outline the immunological features. Results: Among 463 infected patients in the eligible cohort (n=613), 65 (14.0%) were hospitalized, 19 (4.1%) suffered severe COVID-19, and 10 (2.2%) died. Older age (OR=1.59/decade, 95% CI 1.18 to 2.16, p=0.003), requiring family oxygen supplement (2.62, 1.11 to 6.19, 0.028), patients with anti-synthetase syndrome (ASyS) (2.88, 1.12 to 7.34, 0.027, vs. other dermatomyositis), higher IIM disease activity, and prednisone intake >10mg/day (5.59, 2.70 to 11.57, <0.001) were associated with a higher risk of hospitalization. Conversely, 3-dose inactivated vaccination reduced the risk of hospitalization (0.10, 0.02 to 0.40, 0.001, vs. incomplete vaccination). Janus kinase inhibitor (JAKi) pre-exposure significantly reduced the risk of severe COVID-19 in hospitalized patients (0.16, 0.04 to 0.74, 0.019, vs. csDMARDs). ASyS patients with severe COVID-19 had significantly reduced peripheral CD4+ T cells, lower CD4/CD8 ratio, and fewer naive B cells but more class-switched memory B cells compared with controls. Conclusion: ASyS and family oxygen supplement were first identified as risk factors for COVID-19-related hospitalization in patients with IIMs. JAKi pre-exposure might protect IIM patients against severe COVID-19 complications.

Molecular mechanism of α-synuclein aggregation on lipid membranes revealed.

The central hallmark of Parkinson's disease pathology is the aggregation of the α-synuclein protein, which, in its healthy form, is associated with lipid membranes. Purified monomeric α-synuclein is relatively stable in vitro, but its aggregation can be triggered by the presence of lipid vesicles. Despite this central importance of lipids in the context of α-synuclein aggregation, their detailed mechanistic role in this process has not been established to date. Here, we use chemical kinetics to develop a mechanistic model that is able to globally describe the aggregation behaviour of α-synuclein in the presence of DMPS lipid vesicles, across a range of lipid and protein concentrations. Through the application of our kinetic model to experimental data, we find that the reaction is a co-aggregation process involving both protein and lipids and that lipids promote aggregation as much by enabling fibril elongation as by enabling their initial formation. Moreover, we find that the primary nucleation of lipid-protein co-aggregates takes place not on the surface of lipid vesicles in bulk solution but at the air-water and/or plate interfaces, where lipids and proteins are likely adsorbed. Our model forms the basis for mechanistic insights, also in other lipid-protein co-aggregation systems, which will be crucial in the rational design of drugs that inhibit aggregate formation and act at the key points in the α-synuclein aggregation cascade.

Dehydroepiandrosterone-sulfate (DHEAS) promotes MIN6 cells insulin secretion via inhibition of AMP-activated protein kinase.

Derived from adrenal cortical, dehydroepiandrosterone-sulfate (DHEAS) is a precursor to androgens and estrogens, with various bioactivities. Although it has the property of anti-diabetes, the long-term effect of DHEAS on insulin secretion in beta-cells is still unclear. In this study, the effect of DHEAS on the insulin secretion activity in MIN6 cell lines in vitro was assessed. Insulin biosynthesis and secretion were stimulated by DHEAS for 24h. DHEAS inhibited the AMPK activation and upregulated the expression of ACC-1. These findings indicate that DHEAS may exert prominent stimulatory effects on insulin secretion partly via AMPK inhibition and ACC-1 upregulation.