A Functional "Key" Amplified Piezoelectric Effect Modulates ROS Storm with an Open Source for Multimodal Synergistic Cancer Therapy

Chemodynamic therapy (CDT) is a non-invasive strategy for generating reactive oxygen species (ROS) and is promising for cancer treatment. However, increasing ROS in tumor therapy remains challenging. Therefore, exogenous excitation and inhibition of electron-hole pair recombination are attractive for modulating ROS storms in tumors. Herein, a Ce-doped BiFeO3 (CBFO) piezoelectric sonosensitizer to modulate ROS generation and realize a synergistic mechanism of CDT/sonodynamic therapy and piezodynamic therapy (PzDT) is proposed. The mixed Fe2+ and Ce3+ can implement a circular Fenton/Fenton-like reaction in the tumor microenvironment. Abundant ·OH can be generated by ultrasound (US) stimulation to enhance CDT efficacy. As a typical piezoelectric sonosensitizer, CBFO can produce O2 - owing to the enhanced polarization by the US, resulting in the motion of charge carriers. In addition, CBFO can produce a piezoresponse irradiated upon US, which accelerates the migration rate of electrons/holes in opposite directions and results in energy band bending, further achieving toxic ROS production and realizing PzDT. Density functional theory calculations confirmed that Ce doping shortens the diffusion of electrons and improves the conductivity and catalytic activity of CBFO. This distinct US-enhanced strategy emphasizes the effects of doping engineering and piezoelectric-optimized therapy and shows great potential for the treatment of malignant tumors.

An Active Strategy Based on Different Droplet Removal Modes on Polydimethylsiloxane Magnetic Microstructures

The efficient removal of droplets on solid surfaces holds significant importance in the field of fog collection, condensation heat transfer, and so on. However, on current typical surfaces, droplets are characterized by a passive and single removal mode, contingent on the traction force (e.g., capillary force, Laplace pressure, etc.) generated by the surface's physics and chemistry design, posing challenges for enhancing the efficiency of droplet removal. In this paper, an effective active strategy based on different removal modes is demonstrated on magnetic responsive polydimethylsiloxane (PDMS) superhydrophobic microplates (RM-MPSM). By regulating the parameters of microplates and droplet volume, different effective departure modes (top jumping and side departure) can be induced to facilitate the removal of droplets. Moreover, the removal volume of droplets through the side departure mode exhibits a significant reduction compared to that observed in the top jumping mode. The exceptional removal ability of RM-MPSM demonstrates adaptability to diverse functional applications: efficient fog collection, removal of condensation droplets and micro-particles. The efficient modes of droplet removal demonstrated in this work hold significant implications for broadening its application in many fields, such as droplet collection, heat transfer, and anti-icing.

Rapid profiling of transcription factor-cofactor interaction networks reveals principles of epigenetic regulation

Transcription factor (TF)-cofactor (COF) interactions define dynamic, cell-specific networks that govern gene expression; however, these networks are understudied due to a lack of methods for high-throughput profiling of DNA-bound TF-COF complexes. Here we describe the Cofactor Recruitment (CoRec) method for rapid profiling of cell-specific TF-COF complexes. We define a lysine acetyltransferase (KAT)-TF network in resting and stimulated T cells. We find promiscuous recruitment of KATs for many TFs and that 35% of KAT-TF interactions are condition specific. KAT-TF interactions identify NF-κB as a primary regulator of acutely induced H3K27ac. Finally, we find that heterotypic clustering of CBP/P300-recruiting TFs is a strong predictor of total promoter H3K27ac. Our data supports clustering of TF sites that broadly recruit KATs as a mechanism for widespread co-occurring histone acetylation marks. CoRec can be readily applied to different cell systems and provides a powerful approach to define TF-COF networks impacting chromatin state and gene regulation.

Forb stability, dwarf shrub stability and species asynchrony regulate ecosystem stability along an experimental precipitation gradient in a semi-arid desert grassland

Precipitation pattern changes may affect plant biodiversity, which could impact ecosystem stability. However, the effects of changes in precipitation regime on ecosystem stability and their potential mechanisms are still unclear. We conducted a 3-year field manipulation experiment with five precipitation treatments (-40%, -20%, 0% (CK), +20% and +40% of ambient growing season precipitation) in a semi-arid desert grassland to examine the effects of precipitation alterations on functional group stability, species asynchrony, and diversity, and the underlying mchanisms of ecosystem stability using structural equation modelling. Alterations in precipitation had different effects on community biomass and functional group biomass. Moreover, ecosystem stability was mainly driven by forb stability (path coefficient = 0.79). Changes in precipitation had significant effects on soil dissolved inorganic N (P < 0.01) further affecting ecosystem stability through species asynchrony (path coefficient = 0.25). Dwarf shrubs had a stabilizing effect on ecosystem stability (path coefficient = 0.32), mainly via deep roots. Ecosystem stability tended to be lower in the -40% (4.72) and +40% (2.74) precipitation treatments. The common reduction in species asynchrony and stability of forb and dwarf shrub functional groups resulted in lower ecosystem stability under the -40% treatment. The lower stability under the +40% treatment might be ascribed to unimproved dwarf shrub stability. Higher dwarf shrub and forb stability contributed to higher ecosystem stability under normal precipitation changes (±20% treatments) and CK. Species diversity was not a crucial driver of ecosystem stability. Our results indicate that precipitation alteration can regulate ecosystem stability via functional group stability (e.g. forb stability, dwarf shrub stability) and species asynchrony in a semiarid desert grassland.

Defect-Engineered Tin Disulfide Nanocarriers as "Precision-Guided Projectile" for Intensive Synergistic Therapy

Nanoformulations with endogenous/exogenous stimulus-responsive characteristics show great potential in tumor cell elimination with minimal adverse effects and high precision. Herein, an intelligent nanotheranostic platform (denoted as TPZ@Cu-SnS2-x /PLL) for tumor microenvironment (TME) and near-infrared light (NIR) activated tumor-specific therapy is constructed. Copper (Cu) doping and the resulting sulfur vacancies can not only improve the response range of visible light but also improve the separation efficiency of photogenerated carriers and increase the carrier density, resulting in the ideal photothermal and photodynamic performance. Density functional theory calculations revealed that the introduction of Cu and resulting sulfur vacancies can induce electron redistribution, achieving favorable photogenerated electrons. After entering cells through endocytosis, the TPZ@Cu-SnS2-x /PLL nanocomposites show the pH responsivity property for the release of the TPZ selectively within the acidic TME, and the released Cu2+ can first interact with local glutathione (GSH) to deplete GSH with the production of Cu+ . Subsequently, the Cu+ -mediated Fenton-like reaction can decompose local hydrogen peroxide into hydroxyl radicals, which can also be promoted by hyperthermia derived from the photothermal effect for tumor cell apoptosis. The integration of photoacoustic/computed tomography imaging-guided NIR phototherapy, TPZ-induced chemotherapy, and GSH-elimination/hyperthermia enhanced chemodynamic therapy results in synergistic therapeutic outcomes without obvious systemic toxicity in vivo.

Synergizing Pyroelectric Catalysis and Enzyme Catalysis: Establishing a Reciprocal and Synergistic Model to Enhance Anti-Tumor Activity

Nanozyme activity is greatly weakened by the microenvironment and multidrug resistance of tumor cells. Hence, a bi-catalytic nanoplatform, which promotes the anti-tumor activity through "charging empowerment" and "mutual complementation" processes involved in enzymatic and pyroelectric catalysis, by loading ultra-small nanoparticles (USNPs) of pyroelectric ZnSnO3 onto MXene nanozyme (V2 CTx nanosheets), is developed. Here, the V2 CTx nanosheets exhibit enhanced peroxidase activity by reacting V3+ with H2 O2 to generate toxic ·OH, accelerated by the near-infrared (NIR) light mediated heat effect. The resulting V4+ is then converted to V3+ by oxidizing endogenous glutathione (GSH), realizing an enzyme-catalyzed cycle. However, the cycle will lose its persistence once GSH is insufficient; nevertheless, the pyroelectric charges generated by ZnSnO3 USNPs continuously support the V4+ /V3+ conversion and ensure nanoenzyme durability. Moreover, the hyperthermia arising from the V2 CTx nanosheets by NIR irradiation results in an ideal local temperature gradient for the ZnSnO3 USNPs, giving rise to an excellent pyroelectric catalytic effect by promoting band bending. Furthermore, polarized charges increase the tumor cell membrane permeability and facilitate nanodrug accumulation, thereby resolving the multidrug resistance issue. Thus, the combination of pyroelectric and enzyme catalysis together with the photothermal effect solves the dilemma of nanozymes and improves the antitumor efficiency.

[Analysis of clinical data of necrotizing fasciitis secondary to intestinal fistulas and screening the mortality risk factors]

Objective: To analyze the clinical data and to screen the mortality risk factors of necrotizing fasciitis (NF) secondary to intestinal fistulas (NFsIF). Methods: This study was a retrospective observational study. The data of all NFsIF cases who met the inclusion criteria and were admitted into Shandong Provincial Hospital Affiliated to Shandong First Medical University (hereinafter referred to as our unit) from January 2000 to October 2023, and in PubMed, Web of Science, Scopus, China National Knowledge Infrastructure, and Chinese Medical Journal Network databases from its establishment to October 2023 were retrieved and screened. Based on clinical outcomes, the cases were divided into survival group (47 males and 24 females) and death group (16 males and 7 females), and the mortality rate was calculated. Clinical data of patients in the two groups including age, underlying diseases (most related to NF), symptom duration before presentation, white blood cell count, causes of NF, signs of peritonitis, scope of NF involvement, and intestinal management and wound management measures were compared and analyzed to screen the risk factors of death in 94 patients with NFsIF. Results: A total of 94 valid cases were collected, including 90 patients reported in the literature and 4 patients admitted to our unit, with the mortality rate of patients being 24.5% (23/94). Univariate analysis showed that there were no statistically significant differences in age, underlying diseases, symptom duration before presentation, white blood cell count, causes of NF, signs of peritonitis, scope of NF involvement between patients in the two groups (P>0.05); there were statistically significant differences in intestinal treatment and wound treatment between the two groups (with χ2 values of 17.97 and 8.33, respectively, P<0.05). Multivariate logistic regression analysis showed that both intestinal treatment measures and wound treatments measures were independent risk factors for death in 94 NFsIF patients, among which first-stage colostomy+late-stage reconstruction and negative presssure therapy had higher protective effects (with odds ratios of 0.05 and 0.27, respectively, 95% confidence intervals of 0.01-0.33 and 0.08-0.88, respectively, P<0.05). Conclusions: The mortality risk of patients with NFsIF is high. Based on comprehensive treatments, active intestinal and wound treatment may be the key to avoid death, with first-stage colostomy+late-stage reconstruction and negative pressure therapy having higher protective effects.

Three-Step Depletion Strategy of Glutathione: Tunable Metal-Organic-Framework-Engineered Nanozymes for Driving Oxidative/Nitrative Stress to Maximize Ferroptosis Therapy

Ferroptosis is a novel type of nonapoptotic programmed cell death involving the accumulation of lipid peroxidation (LPO) to a lethal threshold. Herein, we propose tunable zeolitic imidazolate framework (ZIFs)-engineered biodegradable nanozymes for ferroptosis mediated by both reactive oxygen species (ROS) and nitrogen species (RNS). l-Arginine is utilized as an exogenous nitric oxide donor and loaded into hollow ZIFs@MnO2 artificial nanozymes, which are formed by etching ZIFs with potassium permanganate and simultaneously generating a MnO2 shell in situ. The constructed nanozymes with multienzyme-like activities including peroxidase, oxidase, and catalase can release satisfactory ROS and RNS through a cascade reaction, consequently promoting the accumulation of LPO. Furthermore, it can improve the efficiency of ferroptosis through a three-step strategy of glutathione (GSH) depletion; that is, the outer MnO2 layer consumes GSH under slightly acidic conditions and RNS downregulates SLC7A11 and glutathione reductase, thus directly inhibiting GSH biosynthesis and indirectly preventing GSH regeneration.

Changes in brain susceptibility in Wilson's disease patients: a quantitative susceptibility mapping study

AIM

To assess changes in the susceptibility of the caudate nucleus (CN), putamen, and globus pallidus (GP) in patients with neurological and hepatic Wilson's disease (WD) by quantitative susceptibility mapping (QSM).

MATERIAL AND METHODS

The brain MRI images of 33 patients diagnosed with WD and 20 age-matched controls were analysed retrospectively. All participants underwent brain T1-weighted, T2-weighted, and QSM imaging using a 1.5 T magnetic resonance imaging (MRI) machine. QSM maps were evaluated with the STISuite toolbox. The quantitative susceptibility levels of the CN, putamen, and GP were analysed using region of interest analysis on QSM maps. Differences among neurological WD patients, hepatic patients, and controls were determined.

RESULTS

Susceptibility levels were significantly higher for all examined structures (CN, putamen and GP) in patients with neurological WD compared with controls (all p<0.05) and hepatic WD patients (all p<0.05). No statistically significant differences were found in susceptibility levels between patients with hepatic WD and controls (all p>0.05).

CONCLUSION

The QSM technique is a valuable tool for detecting changes in brain susceptibility in WD patients, indicating abnormal metal deposition. Notably, the current findings suggest that neurological WD patients exhibit more severe susceptibility changes compared with hepatic WD patients. Therefore, QSM can be utilised as a complementary method to detect brain injury in WD patients.

Architecture of Vanadium-Based MXene Dysregulating Tumor Redox Homeostasis for Amplified Nanozyme Catalytic/Photothermal Therapy

Taking the significance of the special microenvironment for tumor cell survival into account, disrupting tumor redox homeostasis is highly prospective for improving therapeutic efficacy. Herein, a multifunctional 2D vanadium-based MXene nanoplatform, V4 C3 /atovaquone@bovine albumin (V4 C3 /ATO@BSA, abbreviated as VAB) has been elaborately constructed for ATO-enhanced nanozyme catalytic/photothermal therapy. The redox homeostasis within the tumor cells is eventually disrupted, showing a remarkable anti-tumor effect. The VAB nanoplatform with mixed vanadium valence states can induce a cascade of catalyzed reactions in the tumor microenvironment, generating plenty of reactive oxygen species (ROS) with effective glutathione consumption to amplify oxidative stress. Meanwhile, the stable and strong photothermal effect of VAB under near-infrared irradiation not only causes the necrosis of tumor cells, but also improves its peroxidase-like activity. In addition, the release of ATO can effectively alleviate endogenous oxygen consumption to limit triphosadenine formation and inhibit mitochondrial respiration. As a result, the expression of heat shock proteins is effectively suppressed to overcome thermoresistance and the production of ROS can be further promoted due to mitochondrial injury. Moreover, VAB also presents high photoacoustic and photothermal imaging performances. In brief, the multifunctional nanoplatform can provide ATO-enhanced nanozyme catalytic/photothermal therapy with broadening the biomedical applications of vanadium-based MXene.

Biomineralized RuO2 Nanozyme with Multi-Enzyme Activity for Ultrasound-Triggered Peroxynitrite-Boosted Ferroptosis

Ferroptosis, as a non-apoptotic cell death pathway, has attracted increasing attention for cancer therapy. However, the clinical application of ferroptosis-participated modalities is severely limited by the low efficiency owing to the intrinsic intracellular regulation pathways. Herein, chlorin e6 (Ce6) and N-acetyl-l-cysteine-conjugated bovine serum albumin-ruthenium dioxide is elaborately designed and constructed for ultrasound-triggered peroxynitrite-mediated ferroptosis. Upon ultrasound stimulation, the sonosensitizers of Ce6 and RuO2 exhibit highly efficient singlet oxygen (1 O2 ) generation capacity, which is sequentially amplified by superoxide dismutase and catalase-mimicking activity of RuO2 with hypoxia relief. Meanwhile, the S-nitrosothiol group in BCNR breaks off to release nitric oxide (NO) on-demand, which then reacts with 1 O2 forming highly cytotoxic peroxynitrite (ONOO- ) spontaneously. Importantly, BCNR nanozyme with glutathione peroxidase-mimicking activity can consume glutathione (GSH), along with the generated ONOO- downregulates glutathione reductase, avoiding GSH regeneration. The two-parallel approach ensures complete depletion of GSH within the tumor, resulting in the boosted ferroptosis sensitization of cancer cells. Thus, this work presents a superior paradigm for designing peroxynitrite-boosted ferroptosis sensitization cancer therapeutic.

Application of omics technology to investigate the mechanism underlying the role of San Hua Tang in regulating microglia polarization and blood-brain barrier protection following ischemic stroke

ETHNOPHARMACOLOGY RELEVANCE

San Hua Tang (SHT) was first mentioned in the book "The Collection of Plain Questions about Pathogenesis, Qi, and Life." SHT has the effect of dispelling wind and dredging collaterals, dredging viscera, and guiding stagnation, and is used in the treatment of ischemic stroke (IS). SHT is composed of Rheum palmatum L., Magnolia officinalis Rehder & E.H.Wilson, Citrus assamensis S.Dutta & S.C.Bhattacharya, and Notopterygium tenuifolium M.L.Sheh & F.T.Pu, which is the traditional prescription of the Tongxia method for the treatment of stroke. Tongxia is one of the "eight methods" used in traditional Chinese medicine, which plays a role in treating diseases by promoting gastrointestinal peristalsis and defecation. Studies have demonstrated a close relationship between gut microbiota metabolism and cerebral stroke; however, the role of SHT in IS treatment through gut microbiota or intestinal metabolites is unclear.

AIM OF THE STUDY

To explore the connotation of the Xuanfu theory and clarify the mechanism underlying SHT-mediated opening Xuanfu methods. Through metabolomics, 16S rRNA gene sequencing, and molecular biology techniques, research on the changes in the gut microbiota and blood-brain barrier (BBB) will highlight greater strategies for the treatment of stroke.

MATERIALS AND METHODS

We used pseudo-germ-free (PGF) rats combined with an ischemia/reperfusion (I/R) rat model for the follow-up experimental research. PGF rats were prepared by the intragastric administration of an antibiotic cocktail for 6 days, following which SHT was administered for 5 consecutive days. The I/R model was performed 1 day following the concluding administration of SHT. We detected the neurological deficit score, cerebral infarct volume, serum inflammatory factor levels (interleukin IL-6, IL-10, IL-17, and tumor necrosis factor alpha), tight junction-related proteins (Zonula occludens-1, Occludin, and Claudin-5), and small glue plasma cell-associated proteins (Cluster of Differentiation 16/Cluster of Differentiation 206, Matrix metalloproteinase, ionized calcium-binding adapter molecule 1, and C-X3-C Motif Chemokine Ligand 1) 24 h following I/R. Using 16S rRNA gene sequencing and non-targeted metabolomics analysis, we explored the relationship between fecal microecology and serum metabolites. Eventually, we analyzed the correlation between the gut microbiota and plasma metabolic profile as well as the mechanism underlying the SHT-mediated regulation of gut microbiota to protect the BBB following stroke.

RESULTS

In IS treatment, SHT is principally involved in reducing neurological injury and the volume of cerebral infarction; protecting the intestinal mucosal barrier; increasing the levels of acetic acid, butyric acid, and propionic acid; promoting the transformation of microglia to the M2 state; reducing inflammatory reactions; and enhancing tight junctions. These therapeutic effects were not observed in the group treated with antibiotics alone or that treated with SHT in combination with antibiotics, thereby indicating SHT plays a therapeutic role through the gut microbiota.

CONCLUSION

SHT regulates the gut microbiota, inhibits pro-inflammatory factors in rats with IS, alleviates an inflammatory injury of the BBB, and plays a protective role in the brain.

The Role of Radiotherapy in Patients with Refractory Hodgkin Lymphoma after Brentuximab Vedotin and -/or Immune Checkpoint Inhibitors

PURPOSE/OBJECTIVE(S)

Brentuximab vedotin (BV) and immune checkpoint inhibitors (ICIs) had important roles in the treatment of relapse or refractory (R/R) Hodgkin lymphoma (HL). Treatment of refractory disease after BV and -/or ICIs remains a challenge. This study was conducted to evaluate the efficacy and safety of radiotherapy for R/R HL after failure to BV or ICIs.

MATERIALS/METHODS

We retrospectively analyzed patients in two institutions with R/R HL who had failed after first-line therapy, and were refractory to BV or ICIs, and received radiotherapy (RT) thereafter. The overall response rate (ORR), duration of response (DOR), progression-free survival (PFS) and overall survival (OS) were analyzed.

RESULTS

A total of 19 patients were enrolled. First-line systemic therapy consisted of ABVD (84.2%), AVD + ICIs (10.5%) and BEACOPP (5.3%), respectively. After first-line therapy, 15 patients (78.9%) were refractory, and 4 patients (21.1%) relapsed. After diagnosis of R/R HL, 8 patients (42.1%) received BV, and 17 patients (89.5%) received ICIs. RT was delivered in all 19 patients who failed after BV or ICIs. In 16 efficacy-evaluable patients, the ORR and CR rate were 100% and 100%. The median DOR was 17.2 months (range, 7.9 to 46.7 months). 3 patients progressed at outside of the radiation field. The in-field-response rate was 100%. The 12-month PFS and OS were 84.4% and 100%, respectively. No patients were reported with sever adverse events.

CONCLUSION

This study concluded that radiotherapy was effective and safe for refractory HL after BV or ICIs. Further prospective studies were warranted.

2D Piezoelectric BiVO4 Artificial Nanozyme with Adjustable Vanadium Vacancy for Ultrasound Enhanced Piezoelectric/Sonodynamic Therapy

Increasing the yield of reactive oxygen species (ROS) to enhance oxidative stress in cells is an eternal goal in cancer therapy. In this study, BiVO4 artificial nanozyme is developed with adjustable vanadium vacancy for ultrasound (US) enhanced piezoelectric/sonodynamic therapy. Under US excitation, the vanadium vacancy-rich BiVO4 nanosheets (abbreviated Vv -r BiVO4 NSs) facilitate the generation of a large number of electrons to improve the ROS yield. Meanwhile, the mechanical strain imposed by US irradiation makes the Vv -r BiVO4 NSs display a typical piezoelectric response, which tilts the conduction band to be more negative and the valance band more positive than the redox potentials of O2 /O2 •- and H2 O/·OH, boosting the efficiency of ROS generation. Both density functional theory calculations and experiments confirm that the introduction of cationic vacancy can improve the sonodynamic effect. As expected, Vv -r BiVO4 NSs have better peroxidase enzyme catalytic and glutathione depletion activities, resulting in increased intracellular oxidative stress. This triple amplification strategy of oxidative stress induced by US substantially inhibits the growth of cancer cells. The work may open an avenue to achieve a synergetic therapy by introducing cationic vacancy, broadening the biomedical use of piezoelectric materials.

[Efficacy of arteriovenous argatroban versus heparin flush anticoagulation after cardiovascular surgery]

Objective: To compare the effects of arteriovenous argatroban and heparin flushes on platelet count and assess the occurrence of heparin-induced thrombocytopenia (HIT) and other complications in patients undergoing cardiovascular surgeries. Methods: A single-center, prospective randomized control study was conducted. Patients who underwent cardiovascular surgery at Fuwai Hospital, Chinese Academy of Medical Sciences from March to December 2019 were randomly divided into the argatroban group (250 ml normal saline plus 2.5 mg of argatroban) and the heparin group (250 ml normal saline plus 10 mg of heparin). Platelet count, hemorrhage, and thrombosis were assessed. The 4T scores of HIT, the incidences of HIT and other complications were also evaluated. Results: A total of 491 patients (307 males and 184 females) were included in the study, with a mean age of (52.3±13.7) years. There were 245 cases in the argatroban group and 246 cases in the heparin group, respectively. There was no statistically significant difference in the preoperative platelet count between the argatroban and heparin groups [198.0 (161.0, 248.0)×10⁹/L vs 194.0 (157.2, 243.8)×10⁹/L, P=0.498]. Likewise, there were no statistically significant differences in the platelet count between the argatroban and heparin groups at 12 h, 1 day, and 5 days after operation [127.0 (100.0, 154.0)×10⁹/L vs 121.5 (90.2, 149.0)×10⁹/L, 126.0 (97.0, 162.0)×10⁹/L vs 123.5 (88.0, 151.0)×10⁹/L, 168.0 (130.0, 215.0) ×10⁹/L vs 161.0 (101.0, 210.5)×10⁹/L] (repeated measures ANOVA between groups: F=3.327, P=0.069; time comparison: F=532.523, P<0.001; time interaction between groups: F=0.675, P=0.512). The proportion of 4T scores of medium and high scores (≥4)[9.8% (24/245) vs 10.6% (26/246), P=0.777] and incidence of HIT antibody positive [1.63% (4/245) vs 1.63% (4/246), P=0.726] were similar between argatroban group and the heparin group. Mechanical ventilation time was shorter in the argatroban group than that in the heparin group [13.0 (11.0, 21.0) vs 15.5 (12.0, 21.0) h, P=0.020]. Conclusion: Compared with heparin, routine management with argatroban for arteriovenous flush in patients undergoing cardiovascular surgery does not affect the HIT incidence.

Revealing of Intracellular Antioxidants in Dendrobium nobile by High Performance Liquid Chromatography-Tandem Mass Spectrometry

The medicinal plant Dendrobium nobile is an important natural antioxidant resource. To reveal the antioxidants of D. nobile, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was employed for metabolic analysis. The H₂O₂-induced oxidative damage was used in human embryonic kidney 293T (H293T) cells to assess intracellular antioxidant activities. Cells incubated with flower and fruit extracts showed better cell survival, lower levels of reactive oxygen species (ROS), and higher catalase and superoxide dismutase activities than those incubated with root, stem, and leaf extracts (p < 0.01). A total of 13 compounds were newly identified as intracellular antioxidants by association analysis, including coniferin, galactinol, trehalose, beta-D-lactose, trigonelline, nicotinamide-N-oxide, shikimic acid, 5'-deoxy-5'-(methylthio)adenosine, salicylic acid, isorhamnetin-3-O-neohespeidoside, methylhesperidin, 4-hydroxybenzoic acid, and cis-aconitic acid (R² > 0.8, Log₂FC > 1, distribution > 0.1%, and p < 0.01). They showed lower molecular weight and higher polarity, compared to previously identified in vitro antioxidants in D. nobile (p < 0.01). The credibility of HPLC-MS/MS relative quantification was verified by common methods. In conclusion, some saccharides and phenols with low molecular weight and high polarity helped protect H293T cells from oxidative damage by increasing the activities of intracellular antioxidant enzymes and reducing intracellular ROS levels. The results enriched the database of safe and effective intracellular antioxidants in medicinal plants.

Dual Nanozyme-Driven PtSn Bimetallic Nanoclusters for Metal-Enhanced Tumor Photothermal and Catalytic Therapy

Specific generation of reactive oxygen species (ROS) within tumors in situ catalyzed by nanozymes is a promising strategy for cancer therapeutics. However, it remains a significant challenge to fabricate highly efficient nanozymes acting in the tumor microenvironment. Herein, we develop a bimetallic nanozyme (Pt₅₀Sn₅₀) with the photothermal enhancement of dual enzymatic activities for tumor catalytic therapy. The structures and activities of PtSn bimetallic nanoclusters (BNCs) with different Sn content are explored and evaluated systematically. Experimental comparisons show that the Pt₅₀Sn₅₀ BNCs exhibit the highest activities among all those investigated, including enzymatic activity and photothermal property, due to the generation of SnO_2-x with oxygen vacancy (O_vac) sites on the surface of Pt₅₀Sn₅₀ BNCs. Specifically, the Pt₅₀Sn₅₀ BNCs exhibit photothermal-enhanced peroxidase-like and catalase-like activities, as well as a significantly enhanced anticancer efficacy in both multicellular tumor spheroids and in vivo experiments. Due to the high X-ray attenuation coefficient and excellent light absorption property, the Pt₅₀Sn₅₀ BNCs also show dual-mode imaging capacity of computed tomography and photoacoustic imaging, which could achieve in vivo real-time monitoring of the therapeutic process. Therefore, this work will advance the development of noble-metal nanozymes with optimal composition for efficient tumor catalytic therapy.

Abstract 1785: Multi-step engineering of gene-edited CAR T cells using RNA lipid nanoparticles

Autologous chimeric antigen receptor (CAR) T therapies utilize patient cells and can be limited by cell quality, and the high manufacturing burden of viral vectors. As such, there is a need for allogeneic, “off-the-shelf” CAR T cells to make these transformative treatments widely available. However, allogeneic therapies require multiple genetic engineering steps to express CAR and to delete proteins responsible for graft-versus-host disease. Messenger RNA (mRNA) is a promising approach for expression of therapeutic proteins and gene editing nucleases. In this work, we demonstrate a new method for multi-step engineering of gene-edited CAR T cells using RNA lipid nanoparticles (LNPs).

LNPs encapsulating Spy-Cas9 mRNA, TCR and CD52 guide RNA (sgRNA), and CAR mRNA were produced using microfluidics. The CAR construct contained an anti-CD19 scFv binding domain and CD3ζ/4-1BB co-stimulatory domains. Microgram quantities of RNA LNPs were produced to optimize LNP packaging, cargo ratios, and sgRNA combinations. Lead candidates were scaled to milligrams. Purified human primary T cells were cultured, activated, and expanded in serum-free media in plates, flasks and bioreactors. CAR+, TCR− or CD52− cells were generated by addition of the corresponding LNP to activated cells. Cytotoxic killing was determined by co-culture assays with leukemia cells. Gene knockout, CAR expression, viability and cell killing were measured using flow-cytometry.

CD19 CAR was selected as a relevant protein for expression, with TCR and CD52 proteins as gene knockout targets. Single-step addition of CAR LNPs to T cells resulted in transfection efficiencies of 95.0 ± 2.1% and high protein expression. Upon TCR or CD52 LNP addition to T cells, the onset of gene editing was within 48 hours, reaching single target knockout efficiencies of 92.3 ± 3.0% (TCR−), and double knockouts (TCR−/CD52−) of 74.5 ± 6.1%. Similar results were obtained when comparing different LNP batch sizes (microgram to milligram RNA) and cell culture vessels (125,000 to 45 million cells), demonstrating scalability of both the LNP production and cell treatment. Cell viabilities above 90% were maintained at all steps and for all RNA LNPs. Finally, as proof-of-concept for multi-step engineering, sequential addition of TCR LNPs and CAR LNPs resulted in simultaneous CAR expression and TCR gene knockout. These “off-the-shelf” gene-edited CAR T cells were functionally equivalent to non-edited cells in a B cell killing assay, efficiently clearing over 80% of leukemia target cells at a 1:1 ratio.

Our findings demonstrate the advantages of LNPs for RNA delivery to T cells. The simple and gentle nature of LNP cell treatment allows for multiple genetic engineering steps for simultaneous expression and deletion of proteins. Furthermore, LNPs can be easily manufactured using microfluidics, enabling small-scale screening of RNA libraries and rapid scale-up of lead candidates for clinical translation.

Citation Format: Samuel Clarke, R Geczy, A Balgi, S Park, R Zhao, M Swaminathan, R Tieu, N Hoang, C Webb, E Watt, M Wong, M Fujisawa, N Jain, Angela Zhang, Anitha Thomas. Multi-step engineering of gene-edited CAR T cells using RNA lipid nanoparticles [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1785.

Paenibacillus dendrobii sp. nov., an indole-3-acetic acid-producing endophytic bacterium isolated from Dendrobium nobile

A novel rod-shaped, Gram-stain-positive, spore-forming and motile by peritrichous flagella strain, designated HJL G12^T, was isolated from the root of Chinese herb Dendrobium nobile. Strain HJL G12^T grew optimally at pH 7.0, 30 °C and in the presence of 1.0 % NaCl (w/v). Phylogenetic analysis based on 16S rRNA gene and genomic sequences showed that HJL G12^T clustered with Paenibacillus chibensis NBRC 15958^T and Paenibacillus dokdonensis YH-JAE5^T with 98.3 and 98.2 % sequence similarity. The DNA-DNA hybridization values between strain HJL G12^T and the two reference strains were 23.6 % and 24.9 %, respectively. Menaquinone-7 was the only respiratory quinone and meso-diaminopimelic acid was present in the cell-wall peptidoglycan. Antesio-C_15 : 0 and iso-C_16 : 0 were detected to be the major cellular fatty acids. The cellular polar lipid profile contained diphosphatidyglycerol, phosphatidylglycerol, phosphatidylethanolamine, lysyl-phospatidylglycerol and three unidentified aminophospholipids. Based on these results, strain HJL G12^T is considered to represent a novel species within the genus Paenibacillus, for which the name Paenibacillus dendrobii sp. nov. is proposed, with HJL G12^T (=NBRC 115617^T=CGMCC 1.18520^T) as the type strain.

Designable Electrical/Thermal Coordinated Dual-Regulation Based on Liquid Metal Shape Memory Polymer Foam for Smart Switch

Electronic components with tunable resistance, especially with synergistic regulation of thermal conductivity, play important roles in the fields of electronics, smart switch, soft robots, and so on. However, it is still a challenge to get the material with various resistance and thermal conductivity stably without lasting external force. Herein, a liquid metal shape memory polymer foam (LM-SMF) is developed by loading electrically and thermally conductive liquid metal (LM) on deformable foam skeleton. Based on thermal response shape memory effect, the foam skeleton can be reversibly pressed, the process of which enables LM to transfer between connected and disconnected states. As a result, obtained LM-SMF shows that the resistance stably changes from 0.8 Ω (conductor) to 200 MΩ (insulator), and the thermal conductivity difference is up to 4.71 times (0.108 to 0.509 W m^-1 K^-1 ), which indicates that LM-SMF can achieve the electrical and thermal dual-regulation. Moreover, LM-SMF can be used as a designable self-feedback/-warning integrated smart switch or tunable infrared stealth switch. This work proposes a novel strategy to get the material with electrical-thermal coordinated dual-regulation, which is possibly applied in intelligent heating system with real-time monitoring function, electrothermal sensor in the future.

Tumor-Specific NIR-Activatable Nanoreactor for Self-Enhanced Multimodal Imaging and Cancer Phototherapy

Responsive nanosystems for tumor treatment with high specificity and sensitivity have aroused great attention. Herein, we develop a tumor microenvironment responsive and near-infrared (NIR)-activatable theranostic nanoreactor for imaging-guided anticancer therapy. The nanoreactor (SnO2-x@AGP) is comprised of poly(vinylpyrrolidine) encapsulated hollow mesoporous black SnO2-x nanoparticles coloaded with glucose oxidase (GOx) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The constructed nanoreactor can be specifically activated through endogenous H2O2 by an NIR-mediated "bursting-like" process to enhance its imaging and therapeutic functions. Black SnO2-x with abundant oxygen vacancies expedites effective separation of electron-hole pairs from energy-band structure and endows them with strong hyperthermia effect upon NIR laser irradiation. The generating toxic H2O2 with the assistance of GOx provides SnO2-x@AGP with the capacity of oxidative stress therapy. Ascended H2O2 can activate ABTS into ABTS•+. ABTS•+ not only possesses significant NIR absorption properties, but also disrupts intracellular glutathione to generate excessive reactive oxygen species for improved phototherapy, leading to more effective treatment together with oxidative stress therapy. Thus, SnO2-x@AGP with NIR-mediated and H2O2-activated performance presents tumor inhibition efficacy with minimized damage to normal tissues. These outstanding characteristics of SnO2-x@AGP bring an insight into the development of activatable nanoreactors for smart, precise, and non-invasive cancer theranostics.

Liquid-like atoms in dense-packed solid glasses

Revealing the microscopic structural and dynamic pictures of glasses is a long-standing challenge for scientists^1,2. Extensive studies on the structure and relaxation dynamics of glasses have constructed the current classical picture^3-5: glasses consist of some 'soft zones' of loosely bound atoms embedded in a tightly bound atomic matrix. Recent experiments have found an additional fast process in the relaxation spectra^6-9, but the underlying physics of this process remains unclear. Here, combining extensive dynamic experiments and computer simulations, we reveal that this fast relaxation is associated with string-like diffusion of liquid-like atoms, which are inherited from the high-temperature liquids. Even at room temperature, some atoms in dense-packed metallic glasses can diffuse just as easily as they would in liquid states, with an experimentally determined viscosity as low as 10⁷ Pa·s. This finding extends our current microscopic picture of glass solids and might help establish the dynamics-property relationship of glasses⁴.

Fatty Acid Biosynthesis Pathways Are Downregulated during Stigma Development and Are Critical during Self-Incompatible Responses in Ornamental Kale

In Brassicaceae, the papillary cells of the stigma are the primary site of the self-incompatibility (SI) responses. SI preserves the genetic diversity by selectively rejecting irrelevant or incompatible pollen, thus promoting cross fertilization and species fitness. Mechanisms that regulate SI responses in Brassica have been studied mainly on the mature stigma that often undermines how stigma papillary cells attain the state of SI during development. To understand this, we integrated PacBio SMRT-seq with Illumina RNA-seq to construct a de novo full-length transcriptomic database for different stages of stigma development in ornamental kale. A total of 48,800 non-redundant transcripts, 31,269 novel transcripts, 24,015 genes, 13,390 alternative splicing, 22,389 simple sequence repeats, 21,816 complete ORF sequences, and 4591 lncRNAs were identified and analyzed using PacBio SMRT-seq. The Illumina RNA-seq revealed 15,712 differentially expressed genes (DEGs) and 8619 transcription factors. The KEGG enrichment analysis of 4038 DEGs in the “incompatibility” group revealed that the flavonoid and fatty acid biosynthesis pathways were significantly enriched. The cluster and qRT-PCR analysis indicated that 11 and 14 candidate genes for the flavonoid and fatty acid biosynthesis pathways have the lowest expression levels at stigma maturation, respectively. To understand the physiological relevance of the downregulation of fatty acid biosynthesis pathways, we performed inhibitor feeding assays on the mature stigma. The compatible pollination response was drastically reduced when mature stigmas were pre-treated with a fatty acid synthase inhibitor. This finding suggested that fatty acid accumulation in the stigmas may be essential for compatible pollination and its downregulation during maturity must have evolved as a support module to discourage the mounting of self-incompatible pollen.

[P2X7R promotes migration and invasion of Lewis lung cancer cells by activating the AKT signaling pathway]

OBJECTIVE

To explore the role of P2X7 receptor (P2X7R) in migration and invasion of mouse Lewis lung cancer (LLC) cells and examine the tumorigenic ability of LLC cells in P2X7R-knockout mice.

METHODS

RT-PCR was used to examine P2X7R mRNA expression in LLC cells. LLC cells were treated with ATP (as a P2X7R agonist) or 2'- 3'- O- (4-benzoyl- benzoyl)-ATP (BzATP) (a P2X7R agonist) with or without pretreatment with P2X7R antagonist oxATP or A438079. The changes in migration and invasive abilities of the cells were evaluated using wound healing assay and Transwell assay; Western blotting was performed to determine the activation level of the key proteins in the AKT signaling pathway. The effects of BzATP, A438079, and LY294002 (a inhibitor of the PI3K/AKT pathway) on migration and invasion of LLC cells were also examined. In wild-type (WT) and P2X7R knockout (P2X7^-/-) C57BL/6 mice, the growth of subcutaneous LLC cell xenografts were observed by measuring tumor volume and weight.

RESULTS

P2X7R expression was detected in LLC cells. Treatment with P2X7R agonist significantly enhanced migration and invasion abilities of LLC cells, and this effect was inhibited by application of P2X7R antagonists (P < 0.001). Western blotting showed that BzATP treatment of LLC cells significantly increased the expression level of p-AKT protein, which was obviously lowered by treatment with P2X7R antagonist (P < 0.01). P2X7R antagonist strongly inhibited BzATP-induced enhancement of LLC cell migration and invasion (P < 0.001). In the tumor- bearing mice, the tumor volume and weight were significantly lower in P2X7^-/- mice than in WT mice (P < 0.05).

CONCLUSION

P2X7R promotes migration and invasion of LLC cells by activating the AKT signaling pathway, and LLC cells show lowered tumorigenic capacity in P2X7^-/- mice.

Dual Glutathione Depletion Enhanced Enzyme Catalytic Activity for Hyperthermia Assisted Tumor Therapy on Semi-Metallic VSe2/Mn-CS

Semimetallic nanomaterials as photothermal agents for bioimaging and cancer therapy have attracted tremendous interest. However, the poor photothermal stability, low biocompatibility, and single component limit their therapeutic efficiency in cancer treatment. Here, manganese-doped VSe₂ semimetallic nanosheets were prepared and subsequently modified with chitosan (named VSe₂/Mn-CS NSs) for combined enzyme catalytic and photothermal therapy. VSe₂/Mn-CS NSs show high photothermal property with a photothermal conversion efficiency of 34.61% upon 808 nm near-infrared laser irradiation. In the tumor microenvironment, VSe₂/Mn-CS NSs can convert endogenous H₂O₂ into lethal hydroxyl radicals (•OH) to induce cancer cell apoptosis. The interaction between glutathione (GSH) and Se-Se bonds in VSe₂/Mn-CS NSs results in the depletion of GSH level, and the valence states transition of manganese ions is also beneficial for the GSH consumption. This dual depletion of GSH markedly enhances the peroxidase (POD) activity, leading to the high •OH production and the improved therapeutic effect. What is more, the T₁-weighted magnetic resonance and photoacoustic imaging endow VSe₂/Mn-CS NSs with the ability to guide and track the treatment process. Our study provides a research strategy for the application of semimetallic nanomaterials in cancer diagnosis and treatment.

[Study on mechanisms of Th17/Treg imbalance in patients with cystic echinococcosis based on miRNA expression profiles]

OBJECTIVE

To investigate the serum microRNA (miRNA) expression and examine the impact of miRNA expression profiles on T helper type 17 (Th17)/regulatory T cells (Treg) imbalance among patients with cystic echinococcosis, so as to provide insights into the illustration of the mechanisms underlying chronic Echinococcus granulosus infections, and long-term pathogenesis.

METHODS

Total RNA was extracted from the sera of cystic echinococcosis patients and healthy controls, and subjected to high-throughput sequencing with the Illumina sequencing platform. Known miRNAs were annotated and new miRNAs were predicted using the miRBase database and the miRDeep2 tool, and differentially expressed miRNAs were identified. The target genes of differentially expressed miRNAs were predicted using the software miRanda and TargetScan, and the intersection was selected for Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Among the differentially expressed miRNAs with the 20 highest fold changes, miRNAs that targeted genes relating to key transcription factors RORC and FOXP3 that determine the production of Th17 and Treg cells or their important regulatory pathways (PI3K-Akt and mTOR pathways) were matched.

RESULTS

A total of 53 differentially expressed miRNAs were screened in sera of cystic echinococcosis patients and healthy controls, including 47 up-regulated miRNAs and 6 down-regulated miRNAs. GO enrichment analysis showed that these differentially expressed miRNA were involved DNA transcription and translation, cell components, cell morphology, neurodevelopment and metabolic decomposition, and KEGG pathway analysis showed that the differentially expressed miRNA were mainly involved in MAPK, PI3K-Akt and mTOR signaling pathways. Among the differentially expressed miRNAs with the 20 highest fold changes, there were 3 miRNAs that had a potential for target regulation of RORC, and 15 miRNAs that had a potential to target the PI3K-Akt and mTOR signaling pathways.

CONCLUSIONS

Significant changes are found in serum miRNA expression profiles among patients with E. granulosus infections, and differentially expressed miRNAs may lead to Th17/Treg imbalance through targeting the key transcription factors of Th17/Treg or PI3K-Akt and mTOR pathways, which facilitates the long-term parasitism of E. granulosus in hosts and causes a chronic disease.

POS0811 CHARACTERISTICS OF INTESTINAL MICROBIOTA AND ITS RELATIONSHIP WITH LYMPHOCYTE SUBSETS AND CYTOKINES IN PATIENTS WITH VASCULITIS

Background

Vasculitis include a group of autoimmune inflammatory diseases with clinical heterogeneous characterized by inflammation of vascular wall, inflammation of perivascular tissues, and cell-like necrosis[1]. Disorder of gut microbiota, which plays a crucial role in regulating immune cells such as Th1, Th17 and Treg, is associated with other autoimmune diseases[2], and may also be involved in the pathogenesis of vasculitis.

Objectives

To investigate the changes of intestinal microbiota and its correlation with peripheral lymphocyte subsets and inflammatory factors levels in patients with vasculitis.

Methods

Combined with clinical manifestations and laboratory examination, 33 patients with vasculitis who met the 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides[3] and 33 of age- and gender- matched healthy controls (HCs) were selected from the Second Hospital of Shanxi Medical University. The demographic characteristics, general laboratory indicators such as erythrocyte sedimentation rate (ESR), C-reaction protein (CRP), levels of peripheral lymphocyte subpopulations and serum cytokines detected by modified flow cytometry. Fecal microbiota detected by 16S rRNA gene sequencing and compiled and processed using Qiime2 and OTU-profiling tables were collected and analyzed in this study.

Results

Compared with HCs, the richness and diversity of intestinal flora in patients with vasculitis tended to decrease with a statistically significant difference in β diversity (P = 0.025, Figure 1 A and B). More specifically, vasculitis patients had a lower frequency of Firmicutes while higher Proteobacteria and Bacteroidota at the phylum level (P < 0.001, Figure 1C). In vasculitis patients, the relative abundances of 23 bacteria differed from HCs at the genus level was all decreased, including Gemella, Anaeroglobus, Campylobacter, Fournierella, et al (P < 0.001, Figure 1D and E). More importantly, the relative abundance of Muribaculaceae were positively correlated with the absolute count of Th2 and the proportions of Th1 and CD4+T cells and negatively correlated with CRP and ESR, while relative abundance of [Eubacterium]_ventriosum were positively associated with the absolute number of Treg cells and negatively correlated with the percentages of Th2 and CD8+T cells (Figure 1F).

Figure 1.

Differences in α diversity (A), β diversity (B), phylum (C), genus (D), and microbial composition (E) between vasculitis patients and HC and correlation analysis between differential microflora and clinical data in patients with vasculitis (F).

Conclusion

Disturbance of intestinal flora, mainly manifested by decreased diversity and richness, may be involved in the occurrence and development of vasculitis by inducing disroders in lymphocyte subsets and cytokines. Consequently, further studies on the immune mechanisms and influencing factors of intestinal flora may provide new ideas for the diagnosis and treatment of the disease for vasculitis patients.

References

[1]Aierken X, Zhu Q, Wu T, et al. Increased Urinary CD163 Levels in Systemic Vasculitis with Renal Involvement[J]. Biomed Res Int, 2021, 2021: 6637235. DOI: 10.1155/2021/6637235.

[2]Zhang X, Zhang D, Jia H, et al. The oral and gut microbiomes are perturbed in rheumatoid arthritis and partly normalized after treatment[J]. Nat Med, 2015, 21(8): 895-905. DOI: 10.1038/nm.3914.

[3]Jennette JC, Falk RJ, Bacon PA, et al. 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides[J]. Arthritis Rheum, 2013, 65(1): 1-11. DOI: 10.1002/art.37715.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No.82001740).

Disclosure of Interests

None declared

AB0202 GUT MICROBIOTA DYSBIOSIS WERE CLOSELY CORRELATED WITH LYMPHOCYTE SUBSETS AND CYTOKINES IN PATIENTS WITH INFLAMMATORY ARTHRITIS

Background

Inflammatory arthritis includes a group of chronic conditions, particularly rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA)[1].Growing evidences link gut microbiota dysbiosis with the development of inflammatory arthritis[2].

Objectives

The aim of this study was to discover the characters of microbiota in inflammatory arthritis patients and compare the relationship between the microbiota and peripheral lymphocyte subsets and cytokines.

Methods

Fecal samples were collected from 73 arthritis patients (13 PsA, 30 AS, 30 RA patients) and 140 sex- and age-matched healthy controls (HCs). The gut microbiota was studied by sequencing the V3-V4 variable regions of bacterial 16S rRNA genes by the Illumina Miseq PE300 system. Peripheral lymphocyte subsets in these participants were assessed by flow cytometry. Measures of disease activity such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) were recorded. Alpha and Beta diversity was assessed using results from QIIME2 and gut microbiome profiles were compared using linear discriminant analysis (LDA) effect size (LEfSe). R (version 4.0.1) was used for comparative statistics, using pearson correlation analysis to assess the correlation between the relative abundance of genus in the sample and clinical parameters.

Results

Compared with HCs, the richness of gut microbiota (ACE and Chao 1) was significantly lower (p < 0.05) in arthritis patients, and bacterial diversity including Shannon and Simpson indices (p < 0.001) was also significant in arthritis decreased (Figure 1A). β-diversity analysis based on Bray-curtis distance revealed significant differences in microbial communities between arthritis and HCs (Figure 1B, r=0.098, p=0.001, ANOSIM). In addition, compared with HCs at the genus level, 9 bacterial groups were significantly different in PsA (p < 0.05), 19 bacterial groups in AS (p < 0.05), and 17 bacterial groups in RA(p < 0.05) (Figure 1C). There was a significant positive correlation between CD4+T and Prevotella(p<0.01), T and Prevotella(p<0.05), Blautia(p<0.05) as well as Megamonas(p<0.05), Th17 and Prevotella(p<0.01), CD8+T and Megamonas(p<0.01), Th1 and Megamonas(p<0.05), Prevotella(p<0.01),Coprococcus(p<0.05), B and Erysipelotricbaceae_UCG-003(p<0.01), and Erysipelotricbaceae_UCG-003(p<0.01), Anaerostipes(p<0.01), CRP and Fusobacterium(p<0.05) as well as Roseburia(p<0.05). There were negative correlations between T and Erysipelotricbaceae_UCG-003 (p<0.05),CD8+T and Fusobacterium(p<0.01), CD4+T and Fusobacterium(p<0.05), NK and Fusicatenibacter(p<0.05).

Conclusion

The gut microbiota of patients with inflammatory arthritis differs from HC and also varies among individual arthritis, which was closely related to lymphocyte subsets.

References

[1]Wu X. Innate Lymphocytes in Inflammatory Arthritis[J]. Front Immunol, 2020, 11: 565275.DOI: 10.3389/fimmu.2020.565275

[2]Breban M. Gut microbiota and inflammatory joint diseases[J]. Joint Bone Spine, 2016, 83(6): 645-649.DOI: 10.1016/j.jbspin.2016.04.005

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

POS0745 GUT DYSBIOSIS ASSOCIATED WITH PERIPHERAL LYMPHOCYTES AND CYTOKINES IN PATIENTS WITH SJÖGREN’S SYNDROME

Background

Primary Sjögren’s syndrome (pSS) is a systemic autoimmune disease characterized by disorders of lymphocyte subpopulations with various cytokines and auto-antibodies1. Growing evidences suggest that gut microbiome dysbiosis may contribute to the development of pSS2.

Objectives

To investigate the alterations to the gut microbiome and the correlation with peripheral lymphocytes and serum cytokines as well as inflammatory factors in pSS patients.

Methods

A total of 101 pSS patients and 101 age- and sex- matched healthy controls (HCs) were enrolled in this study from The Second Hospital of Shanxi Medical University (Taiyuan, Shanxi, China). Patients fulfilled the 2019 ACR/EULAR classification criteria. We conducted 16S rRNA gene sequencing using fecal microbiota samples and analyzed the peripheral lymphocyte subsets by flow cytometry. Serum cytokines, erythrocyte sedimentation rate (ESR), C-reaction protein (CRP), unstimulated and stimulated whole saliva (UWS and SWS) secretion rate was also collected, respectively. Sequence data were compiled and processed using Qiime2 and OTU-profiling tables were constructed. Correlations between different taxa and gut microbiome, as well as clinical variables, were calculated by Spearman’s rank test.

Results

Patients with pSS exhibited a significant reduction in the richness and diversity of gut microbiota compared with those of HCs (Figure 1A-B, p < 0.05). Detailly, at the phylum level, pSS patients had a lower frequency of Firmicutes while higher Proteobacteria (Figure 1C, p < 0.05). Compared with HCs, 11 species of flora were discovered to be distinctly different at the genus level (p < 0.05). Patients presented fewer Faecalibacterium and Roseburia but more Lactobacillus (Figure 1D, p < 0.05). Lactobacillus negatively correlated with T cells (r=-0.407), CD8+T (r=-0.417) and Th2 (r=-0.323). There was a significant positive correlation between Faecalibacterium and IL-2(r=0.312), IFN-γ(r=0.338), TNF-α levels(r=0.322) (Figure 1E, p < 0.05). As for clinical disease measures, IL-6 increases were in line with ESR and CRP, while IL-2 levels inversely related to CRP. Additional UWS secretion rate and SWS secretion rate had negative correlation with ESR (Figure 1F, p < 0.05).

Conclusion

The structural disorder of gut microbiota was distinct in pSS which were associated with peripheral lymphocyte subsets and cytokines. Disorders of gut microbiota and immune systems may contribute to the occurrence and development of pSS.

References

[1]Mariette X, Criswell LA. Primary Sjogren’s Syndrome. N Engl J Med 2018;378(10):931-39. doi: 10.1056/NEJMcp1702514

[2]Trujillo-Vargas CM, Schaefer L, Alam J, et al. The gut-eye-lacrimal gland-microbiome axis in Sjogren Syndrome. Ocul Surf 2020;18(2):335-44. doi: 10.1016/j.jtos.2019.10.006

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

POS0330 DIFFERENCES IN GUT MICROBIOTA ASSOCIATED WITH LYMPHOCYTE SUBSETS, CYTOKINES AND DISEASE ACTIVITY IN ANKYLOSING SPONDYLITIS

Background

Ankylosing spondylitis (AS), a common chronic inflammatory disease, is a prototype of spondyloarthritis affecting sacroiliac joints and spine with or without peripheral arthritis and other systemic symptoms[1]. Environmental factors, especially microorganisms have been suggested to implicate with AS pathogenesis[2].

Objectives

Utilizing 16S rRNA genes sequencing on the feces of untreated AS patients and healthy controls (HCs), our study aimed to provide an in-depth understanding of AS gut microbiota and identifying a feasible diagnostic strategy for AS.

Methods

Fecal samples were collected from 62 AS patients and 62 age-and-gender- matched HCs. Microbial genome was extracted from approximately 250mg fresh fecal samples from all participants using QIAamp PowerFecal DNA Kit (Qiagen). The V3-V4 variable regions of bacterial 16S rRNA genes were sequenced with the Illumina Miseq PE300 system. QIIME2 based pipeline was used to process the raw sequence data. Alpha and beta diversities were assessed using result from QIIME2, and comparisons of gut microbiome profile were performed using linear discriminant analysis (LDA) effect size (LEfSe) to examine differences between AS and HCs. R (version 4. 0.1) was used for comparative statistics, and pearson’s correlation was used to assess the correlations between the relative abundances of bacterial genera and clinical parameters; correlations with p<0.05 were considered significant.

Results

AS for alpha-diversity, ACE and Chao1 indices were lower in AS compared with those HCs(Figure 1A, p<0.05), though no significant differences observed in Shannon and Simpson index. Bray curtis distance-based beta-diversity analysis revealed significant differences in the microbial community between AS and HCs (Figure 1B, p=0.003, ANOSIM). Fecal microbial communities in AS differed significantly from those in HCs, driven by higher abundances of Escherichia-Shigella, Turicibacter, Enterococcus, et al. and a lower abundance of Agathobacter, Roseburia, Eubacterium_eligens_group, et al (Figure 1C, p<0.05). There was a significant positive correlation between ESR and Klebsiella, Butyricicoccus, Roseburia, CRP and Faecalibacterium, Muribaculaceae, ASDAS-CRP score and Faecalibacterium, Ruminococcus, total lymphocyte cells and Agathobacter, Ruminococcus, T cell and Agathobacter, CD4+T cell and Agathobacter, B cell and Agathobacter, Streptococcus, Th1 and Prevotella, CAG−352, Th2 and Agathobacter, Th17 and Prevotella, Agathobacter, IL-2 and Agathobacter, IL-4 and Agathobacter, IL-6 and Lachnospiraceae_UCG−004, Muribaculaceae, IL-17 and Eubacterium_hallii_group, IFN-gama and Phascolarctobacterium.There were negative correlations between total lymphocytes and Escherichia−Shigella, CD4+T cell and Enterobacteriaceae, Th2 cell and Escherichia−Shigella, IL-10 and CAG−352, Ruminococcus (Figure 2, p<0.05).

Figure 1.

Feature of gut microbiota in AS patients and HCs. (A) Alpha-diversity assessed by richness (Chao1, ACE) and diversity (Shannon, Simpson), Median estimates compared across cohorts. (B) PCoA plot based on the Bray curtis distance of gut microbiota samples from AS patients vs. HC group(p=0.003, ANOSIM). (C) Panel demonstrated the average relative abundance of different genus in AS and HCs. (D) Distribution of gut microbiota at genus level.

Figure 2.

Correlations between the relative abundance of significantly different bacteria and clinical variables. *p<0.05, **p < 0.01, ***p <0 .001, ****p < 0.0001.

Conclusion

Human gut microbiome in patients with AS differed from that of the HCs. Characters of bacteria communities were associated with disease activity.

References

[1]Simone D, Al Mossawi M H, Bowness P. Progress in our understanding of the pathogenesis of ankylosing spondylitis [J]. Rheumatology (Oxford), 2018, 57(suppl_6): vi4-vi9.

[2]Zhou C, Zhao H, Xiao X Y, et al. Metagenomic profiling of the pro-inflammatory gut microbiota in ankylosing spondylitis [J]. J Autoimmun, 2020, 107(102360.

Acknowledgements

This project was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

AB0492 INTESTINAL MICROBIOLOGICAL DISORDER CLOSELY ASSOCIATED WITH PERIPHERAL LYMPHOCYTE SUBSETS AND CYTOKINES IN SYSTEMIC LUPUS ERYTHEMATOSUS

Background

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by widespread inflammation and tissue damage in multiple organs[1]. Microbiome is one of environmental factors that has been suggested to contribute to the occurrence and development of SLE[2].

Objectives

This study aims to the understanding of the pathogenesis of SLE from the perspective of intestinal microorganisms and investigate the associations between flora and peripheral lymphocyte subpopulations and cytokines in SLE patients.

Methods

Fecal samples were collected from 96 patients with SLE, and 96 sex-and age-matched healthy controls (HCs). The gut microbiota were investigated via 16s rRNA sequencing and the peripheral T lymphocyte subsets of these participants were assessed by flow cytometry. Indicators of disease activity such as erythrocyte sedimentation rate (ESR), C-reaction protein (CRP), complement C3 and C4 were recorded. Differential abundance analysis was carried out using the edgeR algorithm. The Wilcoxon rank-sum test was used to compare alpha diversity indices, bacterial abundances, and the F/B ratio between groups. R (version 4.0.1) was used for comparative statistics, and pearson’s correlation analysis was used to assess the correlations between the relative abundances of bacterial genera and serum levels of ESR, CRP, C3 and C4 in the samples; correlations with p < 0.05 were considered significant.

Results

The alpha estimators of richness (ACE and Chao 1) were significantly reduced in SLE feces samples compared with those of HCs (p < 0.0001). Bacterial diversity estimators, including the Shannon (p < 0.001) and Simpson’s (p < 0.01) indices, were also significantly lower in SLE (Figure 1A-D). The microbial community structures of the SLE and HCs could be separated by unweighted UnFrac-based principal coordinates analysis (PCoA) (R = 0.186, and p = 0.001; Figure 1E). Significant differences in gut microbiota composition between SLE and HCs were found using the edgeR algorithm. Compared with HCs, 24 species of flora were discovered to be distinctly different(p < 0.05). Moreover, there was a significant positive correlation between Tregs and Corynebacterium(p < 0.05), CD8+T and Corynebacterium (p < 0.05), CD4+T and Corynebacterium (p < 0.05), T and Corynebacterium (p < 0.05), Th1 and Escherichia−Shigella (p < 0.01), Th2 and Dielma (P<0.001) as well as Eubacterium eligens group (p < 0.05), NK and Faecalibacterium (p < 0.01). as well as Corynebacterium (p < 0.001), IL-6 and Coprococcus (p < 0.05), IL-10 and Eubacterium eligens group (p < 0.001) as well as Veillonella (p < 0.05). and Lachnospira (p < 0.01). As for clinical disease measures, there were positive correlations between CRP and Eubacterium ventriosum (p < 0.05). and Coprococcus (p < 0.05), C4 and the abundance of Corynebacterium (p < 0.05) (Figure 1F).

Conclusion

Patients with gut dysbiosis that mainly characterized by reduced the diversity and impaired abundance of the intestinal flora. Abnormality of T cell subsets and cytokines, especially the level of CD4+T, CD8+T, NK, Treg, Th, IL-6 and IL-10 cells contributes to the occurrence and progression of SLE, which may be related to the disturbance of gut microbiota. The discovery of the associated intestinal microbiota of SLE may provide a new idea for treatment.

References

[1]Fava A, Petri M. Systemic lupus erythematosus: diagnosis and clinical management. J Autoimmun. (2019) 96:1–13. 10.1016/j.jaut.2018.11.001

[2]He Z, Shao T, Li H, Xie Z, Wen C: Alterations of the gut microbiome in Chinese patients with systemic lupus erythematosus. Gut pathogens 2016, 8:64.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

Hydrogen sulphide signalling in plant response to abiotic stress

Throughout their whole life cycle, higher plants are often exposed to diverse environmental stresses, such as drought, salinity, heavy metals and extreme temperatures. In response to such stress, plant cells initiate signalling transduction, resulting in downstream responses, such as specific gene transcription and protein expression. Accumulating evidence has revealed that hydrogen sulphide (H₂ S) serves as a signalling molecule in plant acclimation to stressful conditions. More important, H₂ S interacts with other signalling molecules and phytohormones, contributing to transcriptional regulation and post-translational modification. Overall, the H₂ S-mediated signalling pathway and its interaction with other signals remains elusive. Here, we describe the role of the H₂ S signalling network in regulating physiological and molecular processes under various abiotic stresses.

POS0556 ALTERATION OF THE GUT MICROBIOTA IN CHINESE POPULATION WITH RHEUMATOID ARTHRITIS

Background

Rheumatoid arthritis (RA) is an aggressive immune-mediated joint disease characterized by synovial proliferation and inflammation, cartilage destruction, and joint destruction. Growing evidences suggests a chronic inflammatory response induced by gut microbiome critically contribute to the development of rheumatoid arthritis.

Objectives

The aim of this study was to evaluate and quantify differences in the composition of gut microbiota in RA patients and investigate the associations between flora and clinical variables in RA patients.

Methods

Fecal samples from 145 RA patients and 145 age- and gender- matched healthy controls (HCs) were collected for bacterial 16S rRNA genes sequencing. The alpha-diversity, beta-diversity and the microbial composition (at the phylum and genus level) analysis of the gut microbiome were used to define the difference of gut microbiota profiles between RA patients and HCs. The peripheral lymphocytes of these patients were assessed by flow cytometry, and inflammatory biomarkers (ESR, CRP), auto-antibodies(ACPA, MCV) and cytokines measured by ELISA were recorded. Correlations between different taxa and clinical variables, were calculated by Spearman’s rank test.

Results

Consistent with trends observed for diversity, patients with RA had a lower richness compared with those of HCs (p < 0.01, Figure 1a), suggesting gut microbiome was markedly less diverse in composition in RA. Bray curtis distance-based beta diversity analysis revealed significant differences in the microbial community between RA and HCs (ANOSIM, R2=0.061, p=0.001, Figure 1b). Ten selected taxonomic biomarkers at different phylogenetic levels showed great discriminant ability, with Log10 LDA score > 4.0 (Figure 1e-g). Detailly, at the phylum level, RA patients had a lower frequency of Firmicutes while higher Proteobacteria. RA patients presented fewer Faecalibacterium but more Escherichia_Shigella at the genus level (Figure 1c-d). PICRUSt analysis found that in the KEGG pathways, the microbial gene functions related to Propanoate metabolism were higher in the fecal microbiome of RA patients (Figure 1h). Escherichia_Shigella positively correlated with ACPA antibodies (r=0.176, p < 0.05) and IL-4 (r=0.204, p < 0.05, Figure 1i), wheras Faecalibacterium as a probiotic showed no significant correlation with our clinical measures.

Figure 1.

Conclusion

Specific gut microbiota played an important role in the pathogenesis of RA, which may aid in the diagnosis or determination of the susceptibility of individuals to RA via detection of the gut microbiome.

References

[1]de Oliveira GLV, Leite AZ, Higuchi BS, et al. Intestinal dysbiosis and probiotic applications in autoimmune diseases. Immunology 2017;152(1):1-12. doi: 10.1111/imm.12765

[2]Chen J, Wright K, Davis JM, et al. An expansion of rare lineage intestinal microbes characterizes rheumatoid arthritis. Genome Med 2016;8(1):43. doi: 10.1186/s13073-016-0299-7

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared.

POS1153 CHARACTERISTICS OF GUT MICROBIOME AND THEIR ASSOCIATIONS WITH PERIPHERAL LYMPHOCYTE SUBPOPULATIONS AND CYTOKINES IN RHEUMATOID ARTHRITIS PATIENTS COMPLICATED WITH OSTEOPOROSIS

Background

Osteoporosis(OP) is one of the major comorbidities of rheumatoid arthritis(RA) which is associated with immune disorders[1]. The gut microbiota has been highlighted to be an important environmental factor to influence immune system in maintaining bone health and regulating bone remodeling[2]. However, the alterations of intestinal flora and its relationship with immune system in RA patients with OP are unclear.

Objectives

To investigate the characteristics of gut microbiome as well as the associations between flora and peripheral lymphocyte subpopulations and cytokines in rheumatoid arthritis patients complicated with osteoporosis.

Methods

Total 28 RA patients were divided into 14 RA-non-OP and 14 gender- and age-matched RA-OP groups according to their bone mineral density (BMD) and the history of fragility fracture. Gut microbiota of participants were investigated by 16s rRNA and peripheral lymphocyte subsets and cytokines were assessed via flow cytometry. Indicators like erythrocyte sedimentation rate (ESR), C-reaction protein (CRP), anti-cyclic citrullinated peptide antibody (ACPA) and anti-mutated citrullinated vimentin (MCV) antibody were recorded meanwhile. Alpha diversity (ACE, Chao1, Simpson, Shannon) and beta diversity indices were analyzed using QIIME2. Biomarker species were recognized based on STEMP. Spearman analysis was adopted for correlation of two variables. All P-values reported herein were two-tailed and P-value<0.05 was taken as statistically significant.

Results

The alpha-diversity have no significant difference between RA-non-OP and RA-OP groups (P >0.05, Figure 1A). The community structure of microflora differed between two groups (P <0.05, Figure 1B). As for the composition of intestinal flora at genus level, Faecalibacterium, Proteus, Catenibacterium, Enterobacter and Erysipelatoclostridium in RA-OP group as well as Lachnospiraceae_ND3007_group, Parasutterella, Megasphaera, Tyzzerella, UCG-005, Clostridium_sensu_stricto_1, UCG-002, Lachnospiraceae_NK4A136_group, Christensenellaceae_R-7_group, Prevotella, Parabacteroides in RA-non-OP group were significantly increased (Figure 1C). There were positive correlations between Lachnospiraceae_NK4A136_group and the level of T, Th1 and Th17 cells, but negative relevance with ESR, CRP and IL-10 (P <0.05). The relative abundance of Faecalibacterium was negatively correlated with IL-2, IL-4, TNF-α and positively with MCV (P <0.05). Clostridium_sensu_stricto_1 and Lachnospiraceae_ND3007_group were negatively correlated with ACPA and MCV respectively as well as IL-2 (P <0.05, Figure 1D-E).

Conclusion

Abnormality of immune system may contribute directly or indirectly to OP in RA, which may be related to the disturbance of gut microbiota.

References

[1]Horta-Baas G, Romero-Figueroa MDS, Montiel-Jarquín AJ, et al. Intestinal Dysbiosis and Rheumatoid Arthritis: A Link between Gut Microbiota and the Pathogenesis of Rheumatoid Arthritis. J Immunol Res. 2017;2017:4835189.

[2]Raterman HG, Bultink IE, Lems WF. Osteoporosis in patients with rheumatoid arthritis: an update in epidemiology, pathogenesis, and fracture prevention. Expert Opin Pharmacother. 2020 Oct;21(14):1725-1737.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

AB0844 Characterizing Gut Microbial Enterotypes in undifferentiated spondyloarthritis

Background

The presence of dysbiosis in the gut microbiome is responsible for the initiation of autoinflammatory and autoimmune diseases. However, such dysbiosis is difficult to characterize in sweeping generalization owing to the high dimensional complexity of the gut microbiota.

Objectives

This study designed to characterize the gut microbial enterotype in patients with undifferentiated spondyloarthritis (USpA) from lower dimensionality and describe the dysbiosis.

Methods

The Fecal samples of 105 patients were diagnosed with USpA and gender- and age- matched 105 healthy controls (HC) were included in the intestinal microbiota composition analyses via Illumina sequencing of bacterial 16S rRNA genes. Microbiota-derived clustering was performed using Dirichlet multinomial mixtures (DMM) modeling. To identify discriminative features in abundance between enterotypes, the Linear Discriminant Analysis Effect Size (LEfSe) algorithm was used with the online interface Galaxy (Log10 LDA score > 4.0). The phyloseq R package to compute alpha diversity (ACE, Chao1, Shannon and Simpson indices), beta diversity (Bray-Curtis dissimilarity) and the microbial composition (at the genus level) to describe the richness and diversity of the microbiota between two enterotypes.

Results

As showed in Figure 1A and C, by evaluating the Laplace approximation to the negative log mode, 2 distinctly enterotypes were identified in the USpA and HC microbiota dataset. LEfSe Analysis indicated the distinctive abundant microbial clades between the 2 enterotypes (LDA score >4) in both the USpA and HC group respectively. At the genus level, Faecalibacterium and Prevotella was the driving genus of enterotype 1 and Bacteroides contributed to enterotype 2 (Figure 1B, D). The alpha-diversity and beta diversity between the distinctive enterotypes was highly significantly different (P < 0.01, Figure 1E, F). Distinct bacterial profiles were also observed in enterotype 1 and 2 (Figure 1G). Interestingly, no significant differences were found between USpA patients and HC for the corresponding same intestinal type. This may be because USpA was at a comparatively early stage of spondyloarthritis (SpA).

Conclusion

Two significantly distinct bacterial microbiota structures existed in the USpA patients which was consistent with the general healthy population.

References

[1]Belkaid Y, Hand TW: Role of the microbiota in immunity and inflammation. Cell 2014, 157(1):121-141.

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared

OP0087 INTEGRATED SYSTEMS ANALYSIS OF THE GUT MICROBIOTA PHENOTYPES IN THE RHEUMATOID ARTHRITIS

Background

Patients with rheumatoid arthritis (RA) displays extreme dysbiosis in microbiota. However, such dysbiosis is difficult to characterize owing to the high dimensional complexity of the gut microbiota1,2.

Objectives

The aim of this study was to discover the enterotype characters of intestinal flora in RA.

Methods

Fecal samples from 145 RA patients were collected for bacterial 16S rRNA genes sequencing. Mathematical modeling using Dirichlet multinomial mixtures (DMM) was applied to describe the variability in the microbiome data and cluster samples into enterotypes. The alpha-diversity, beta-diversity and the microbial composition analysis of the gut microbiome were used to define the difference of gut microbiota profiles between different enterotypes. The nonredundant taxonomic biomarkers for each enterotype were selected by using LEfSe. Inflammatory biomarkers (ESR, CRP), auto-antibodies(ACPA, MCV), peripheral lymphocytes subsets and cytokines were analyzed in our cohort using the Kruskal-Wallis test.

Results

Laplace approximation of DMM indicated two significantly distinct bacterial microbiota structures (RAE1 and RA E2) existed in the dataset (Figure 1a). Principal co-ordinates analyses confirmed that these two microbiota states explained a reasonable proportion of observed variance in microbiota composition(ANOSIM R2 = 0.267, p = 0.001; Figure 1b), with distinct bacterial genus distribution of in each enterotype (Figure 1c). RA E1 were primarily dominated by Prevotella while RA E2 by Bacteroides. Interestingly, Chao1, ACE, Shannon and Simpson revealed a higher alpha diversity in Prevotella-enriched enterotype (p< 0.001, Figure 1d). Fourteen selected taxonomic biomarkers at different phylogenetic levels showed great discriminant ability, with Log10 LDA score > 4.0 (Figure 1e-g). Further, inflammatory biomarkers (ESR, CRP) and auto-antibodies(ACPA, MCV) as well as the number of T, B and CD4+T, Th1, Th2, Th17, and Treg were consistent in RA E1 and RA E2 (p > 0.05, Figure 2h). But CD8+T were significantly higher in RA E2 than in RA E2 (p < 0.05).

Conclusion

Despite RA gut microbiota being of different dysbiosis, two patterns of dysbiosis, designated as RA-enterotypes, were predominant among the RA patient cohort. RA E2 exhibited a loss of Prevotella but a growth of Bacteroides, while RA E1 presented the opposite results.

References

[1]Arumugam M, Raes J, Pelletier E, et al. Enterotypes of the human gut microbiome. Nature 2011;473(7346):174-80. doi: 10.1038/nature09944

[2]Costea PI, Hildebrand F, Arumugam M, et al. Enterotypes in the landscape of gut microbial community composition. Nat Microbiol 2018;3(1):8-16. doi: 10.1038/s41564-017-0072-8

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 82001740).

Disclosure of Interests

None declared.

[Effect of maternal exposure to lipopolysaccharide during pregnancy on allergic asthma in offspring in mice]

Objective: To investigate the effect of maternal exposure to lipopolysaccharide during pregnancy on allergic asthma in offspring in mice. Methods: Animal experimental research was carried out from June 2019 to June 2021.Pregnant C57BL/6J mice were randomly divided into 2 groups by intraperitoneal injection with 7 μg/kg lipopolysaccharide (LPS) or phosphate buffered saline (PBS) at day 15.5 of gestation. After birth, 6 offspring were randomly chosen from each group at the age of 4 weeks, and stimulated with house dust mites (HDM) or PBS, further divided into 4 groups, such as LPS+PBS group, LPS+HDM group, PBS+PBS group, PBS+HDM group, with 3 mice in each group. The cough and wheezing were observed, the histological changes in lung tissue were examined after HE staining, and the expression of inflammatory factors including interleukin (IL)-4, IL-6, IL-17A, IL-23, interferon (IFN)-α and IFN-β in the lung tissue were detected by high-throughput liquid protein chip detection. T test or rank sum test was used for the comparison among these groups. Results: The asthma-like airway inflammation was more obvious in PBS+HDM group after stimulated by HDM than that in PBS+PBS group, nevertheless, this manifestation in LPS+HDM group was milder than that in PBS+HDM group. HE staining showed that inflammatory cell aggregation in the lung tissue in PBS+HDM group was significantly higher than that in PBS+PBS group (4.0 (3.5, 4.0) vs. 0 (0, 0.5), Z=2.02, P=0.043), while it was much lower in LPS+HDM group compared to PBS+HDM group (1.0 (0.5, 1.5) vs. 4.0 (3.5, 4.0), Z=1.99, P=0.046). High-throughput liquid protein chip detection of lung tissue showed that IL-6, IL-23 and IFN-β levels were significantly higher in PBS+HDM group when compared to those in PBS+PBS group ((114±3) vs. (94±4) ng/L, (210±4) vs. (173±7) ng/L, (113±2) vs. (94±4) ng/L, t=4.37, 4.84, 3.96, all P<0.05), while the levels of IL-6, IL-23, IFN-α, IFN-β in LPS+HDM group were significantly lower than those in PBS+HDM group ((87±5) vs. (114±3) ng/L, (171±7) vs. (210±4) ng/L, (16.1±0.6) vs. (20.9±0.3) ng/L, (95±1) vs. (113±2) ng/L, t=5.07, 5.07, 7.28, 7.47, all P<0.05). Conclusions: Prenatal low dose LPS exposure can reduce offspring's airway inflammatory reactions and prevent the development of allergic disease. Maternal infection during pregnancy may affect the occurrence and development of allergic asthma in offspring.

[Ferroptosis in laryngeal squamous cell carcinoma and its regulation by M2 macrophage-derived exosomes]

Objective: To investigate ferroptosis in laryngeal squamous cell carcinoma (LSCC) and its regulation by M2 macrophage-derived exosomes. Methods: LSCC and adjacent noncancerous tissue samples were collected from 32 patients treated in the Department of Otorhinolaryngology, Head and Neck Surgery of the Second Affiliated Hospital of Harbin between September 2018 and April 2021, including 26 males and 6 females, aged 43-79 years. The expressions of ferroptosis marker glutathione peroxidase 4(GPX4) in LSCC and adjacent noncancerous tissues were detected by immunohistochemistry and reverse transcriptase-polymerase chain reaction(RT-PCR). The correlations between GPX4 expression and clinicopathological factors in LSCC were analyzed. Biological changes of TU212 cells after treated with ferroptosis-induced agent erastin were detected by transmission electron microscope, cell counting kit-8(CCK-8), clone test, reactive oxygen species(ROS), malondialdehyde(MDA), glutathione(GSH), JC-1, RT-PCR and western blot. Exosomes were isolated from the supernatant of M0/M2 macrophages (M0-exos/M2-exos) and co-incubated with erastin-treated TU212 cells to detect the change of ferroptosis in cells of each group. The data were analyzed by SPSS software of version19.0. Results: GPX4 expression in LSCC tissues was significantly higher than that in adjacent noncancerous tissues (2.04±0.65 vs. 0.99±0.09, F=30.36, P<0.001), and was closely related to T stage and clinical stage (Ⅰ-Ⅱvs.Ⅲ-Ⅳ: 1.75±0.39 vs. 2.18±0.71, F=2.25, P<0.05; T1-2 vs. T3-4: 1.71±0.42 vs. 2.20±0.69, F=2.06, P<0.05). In TU212 cells treated with erastin, mitochondrial crest became smaller, membrane density increased, proliferation rate decreased, intracellular ROS level increased, mitochondrial membrane potential depolarized, GSH content decreased, intracellular MDA level increased and expressions of GPX4 mRNA and protein decreased. Change of M0 into M2 macrophages was induced by IL-4 stimulation. When erastin-treated TU212 cells were incubated with M2-exos, cell proliferation was partially restored and GPX4 expression was enhanced, and also with the recoveries of levels of ROS, MDA and GSH (all P<0.05). Conclusions: Ferroptosis is one of the cell death ways of LSCC. M2-exos may inhibit ferroptosis of LSCC cells.