[Efficacy and safety of various doses of hybutimibe monotherapy or in combination with atorvastatin for primary hypercholesterolemia: a multicenter, randomized, double-blind, double-dummy, parallel-controlled phase Ⅲ clinical trial]

Objective: To evaluate the efficacy and safety of hybutimibe monotherapy or in combination with atorvastatin in the treatment of primary hypercholesterolemia. Methods: This was a multicenter, randomized, double-blind, double-dummy, parallel-controlled phase Ⅲ clinical trial of patients with untreated primary hypercholesterolemia from 41 centers in China between August 2015 and April 2019. Patients were randomly assigned, at a ratio of 1∶1∶1∶1∶1∶1, to the atorvastatin 10 mg group (group A), hybutimibe 20 mg group (group B), hybutimibe 20 mg plus atorvastatin 10 mg group (group C), hybutimibe 10 mg group (group D), hybutimibe 10 mg plus atorvastatin 10 mg group (group E), and placebo group (group F). After a dietary run-in period for at least 4 weeks, all patients were administered orally once a day according to their groups. The treatment period was 12 weeks after the first dose of the study drug, and efficacy and safety were evaluated at weeks 2, 4, 8, and 12. After the treatment period, patients voluntarily entered the long-term safety evaluation period and continued the assigned treatment (those in group F were randomly assigned to group B or D), with 40 weeks' observation. The primary endpoint was the percent change in low density lipoprotein cholesterol (LDL-C) from baseline at week 12. Secondary endpoints included the percent changes in high density lipoprotein cholesterol (HDL-C), triglyceride (TG), apolipoprotein B (Apo B) at week 12 and changes of the four above-mentioned lipid indicators at weeks 18, 24, 38, and 52. Safety was evaluated during the whole treatment period. Results: Totally, 727 patients were included in the treatment period with a mean age of (55.0±9.3) years old, including 253 males. No statistical differences were observed among the groups in demographics, comorbidities, and baseline blood lipid levels. At week 12, the percent changes in LDL-C were significantly different among groups A to F (all P<0.01). Compared to atorvastatin alone, hybutimibe combined with atorvastatin could further improve LDL-C, TG, and Apo B (all P<0.05). Furthermore, there was no significant difference in percent changes in LDL-C at week 12 between group C and group E (P=0.991 7). During the long-term evaluation period, there were intergroup statistical differences in changes of LDL-C, TG and Apo B at 18, 24, 38, and 52 weeks from baseline among the statins group (group A), hybutimibe group (groups B, D, and F), and combination group (groups C and E) (all P<0.01), with the best effect observed in the combination group. The incidence of adverse events was 64.2% in the statins group, 61.7% in the hybutimibe group, and 71.0% in the combination group during the long-term evaluation period. No treatment-related serious adverse events or adverse events leading to death occurred during the 52-week study period. Conclusions: Hybutimibe combined with atorvastatin showed confirmatory efficacy in patients with untreated primary hypercholesterolemia, which could further enhance the efficacy on the basis of atorvastatin monotherapy, with a good overall safety profile.

Development of a laser-based angle-resolved-photoemission spectrometer with sub-micrometer spatial resolution and high-efficiency spin detection

Angle-resolved photoemission spectroscopy with sub-micrometer spatial resolution (μ-ARPES), has become a powerful tool for studying quantum materials. To achieve sub-micrometer or even nanometer-scale spatial resolution, it is important to focus the incident light beam (usually from synchrotron radiation) using x-ray optics, such as the zone plate or ellipsoidal capillary mirrors. Recently, we developed a laser-based μ-ARPES with spin-resolution (LMS-ARPES). The 177 nm laser beam is achieved by frequency-doubling a 355 nm beam using a KBBF crystal and subsequently focused using an optical lens with a focal length of about 16 mm. By characterizing the focused spot size using different methods and performing spatial-scanning photoemission measurement, we confirm the sub-micron spatial resolution of the system. Compared with the μ-ARPES facilities based on the synchrotron radiation, our LMS-ARPES system is not only more economical and convenient, but also with higher photon flux (>5 × 10¹³ photons/s), thus enabling the high-resolution and high-statistics measurements. Moreover, the system is equipped with a two-dimensional spin detector based on exchange scattering at a surface-passivated iron film grown on a W(100) substrate. We investigate the spin structure of the prototype topological insulator Bi₂Se₃ and reveal a high spin-polarization rate, confirming its spin-momentum locking property. This lab-based LMS-ARPES will be a powerful research tool for studying the local fine electronic structures of different condensed matter systems, including topological quantum materials, mesoscopic materials and structures, and phase-separated materials.

Association of non-alcoholic fatty liver disease with total testosterone in non-overweight/obese men with type 2 diabetes mellitus

PURPOSE

Non-alcoholic fatty liver disease (NAFLD) is considered as both a vital risk factor and a consequence of type 2 diabetes mellitus (T2DM). Low total testosterone (TT) is common in men with T2DM, contributing to increased risks of metabolic diseases. This study aimed to investigate the association between TT levels and the prevalence of NAFLD in men with T2DM.

METHODS

In this cross-sectional study, 1005 men with T2DM were enrolled in National Metabolic Management Center (MMC) of First Affiliated Hospital of Wenzhou Medical University between January 2017 and August 2021. NAFLD was diagnosed using ultrasound as described by the Chinese Liver Disease Association. Overweight/obesity was defined as body mass index (BMI) ≥ 25 kg/m² according to WHO BMI classifications.

RESULTS

Individuals without NAFLD had higher serum TT levels than those with NAFLD. After adjustments for potential confounding factors, the top tertile was significantly associated with lower prevalence of NAFLD compared with the bottom tertile of TT level [odds ratio (OR) 0.303, 95% confidence interval (CI) 0.281-0.713; P < 0.001]. The association between TT with NAFLD in individuals with normal weight (OR 0.175, 95% CI 0.098-0.315; P < 0.001) was stronger than in individuals with overweight/obesity (OR 0.509, 95% CI 0.267-0.971; P = 0.040). There was a significant interaction of TT with overweight/obesity (P for interaction = 0.018 for NAFLD).

CONCLUSION

Higher serum TT was significantly associated with a lower prevalence of NAFLD in men with T2DM. We found that the relationship of TT and NAFLD was stronger in individuals with non-overweight/obesity.

Association between Iodized Salt Intake and Cognitive Function in Older Adults in China

OBJECTIVES

To investigate the association between iodized salt intake and cognitive function in older adults.

DESIGN

A cross-sectional study.

SETTINGS

Individuals from the Zhejiang Major Public Health Surveillance Program (ZPHS).

PARTICIPANTS

Data of 10,217 participants (including 4,680 coastal residents and 5,537 inland residents) aged ≥ 60 years were analyzed.

MEASUREMENTS

Salt intake was evaluated using a questionnaire, and participants were stratified into the following three groups: iodized salt, non-iodized salt, and mixed salt. Cognitive function was assessed through the Mini-Mental State Examination and defined using education-specific cut-off points. Logistic regression models controlling for an extensive range of potential confounders were generated to examine the association between salt intake and cognitive function among all participants.

RESULTS

Data from 10,217 participants with a 16.1% prevalence of cognitive impairment were analyzed. Compared with non-iodized salt intake, consumption of iodized salt was inversely associated with cognitive impairment (odds ratio [OR], 0.410; 95% confidence interval [CI], 0.351-0.480; P < 0.001) in all participants after multivariable adjustment. An association between iodized salt intake and cognitive impairment was observed in coastal (OR, 0.441; 95% CI, 0.340-0.572; P < 0.001) and inland residents (OR, 0.569; 95% CI, 0.439-0.738; P < 0.001). Despite the insufficient sample size, the results for individuals consuming mixed salt suggested an inverse association between mixed salt intake and cognitive impairment among coastal residents (OR, 0.598; 95% CI, 0.405-0.885; P = 0.010) after multivariable adjustment.

CONCLUSION

Our results indicate that iodized salt intake may reduce the risk of cognitive impairment in older adults living in coastal or inland areas, and the protective effect of iodized salt intake is greater in coastal areas than in inland areas.

CRISPR-Cas and catalytic hairpin assembly technology for target-initiated amplification detection of pancreatic cancer specific tsRNAs

Transfer RNA-derived small RNAs (tsRNAs) tRF-LeuCAG-002 (ts3011a RNA) is a novel class of non-coding RNAs biomarker for pancreatic cancer (PC). Reverse transcription polymerase chain reaction (RT-qPCR) has been unfit for community hospitals that are short of specialized equipment or laboratory setups. It has not been reported whether isothermal technology can be used for detection, because the tsRNAs have rich modifications and secondary structures compared with other non-coding RNAs. Herein, we have employed a catalytic hairpin assembly (CHA) circuit and clustered regularly interspaced short palindromic repeats (CRISPR) to develop an isothermal and target-initiated amplification method for detecting ts3011a RNA. In the proposed assay, the presence of target tsRNA triggers the CHA circuit that transforms new DNA duplexes to activate collateral cleavage activity of CRISPR-associated proteins (CRISPR-Cas) 12a, achieving cascade signal amplification. This method showed a low detection limit of 88 aM at 37 °C within 2 h. Moreover, it was demonstrated for the first time that, this method is less likely to produce aerosol contamination than RT-qPCR by simulating aerosol leakage experiments. This method has good consistency with RT-qPCR in the detection of serum samples and showed great potential for PC-specific tsRNAs point-of-care testing (POCT).

MicroRNAs in extracellular vesicles: Sorting mechanisms, diagnostic value, isolation, and detection technology

MicroRNAs (miRNAs) are a class of short, single-stranded, noncoding RNAs, with a length of about 18–22 nucleotides. Extracellular vesicles (EVs) are derived from cells and play a vital role in the development of diseases and can be used as biomarkers for liquid biopsy, as they are the carriers of miRNA. Existing studies have found that most of the functions of miRNA are mainly realized through intercellular transmission of EVs, which can protect and sort miRNAs. Meanwhile, detection sensitivity and specificity of EV-derived miRNA are higher than those of conventional serum biomarkers. In recent years, EVs have been expected to become a new marker for liquid biopsy. This review summarizes recent progress in several aspects of EVs, including sorting mechanisms, diagnostic value, and technology for isolation of EVs and detection of EV-derived miRNAs. In addition, the study reviews challenges and future research avenues in the field of EVs, providing a basis for the application of EV-derived miRNAs as a disease marker to be used in clinical diagnosis and even for the development of point-of-care testing (POCT) platforms.

Highly efficient and automated isolation technology for extracellular vesicles microRNA

MicroRNA (miRNA) in extracellular vesicles (EVs) has great potential to be a promising marker in liquid biopsy. However, the present EV isolation methods, such as ultracentrifugation, have complicated and long-time operation, which impedes research on EV miRNA. The downstream complex miRNA extraction process will also significantly increase the detection cycle and loss. We first established a simple automated technique to efficiently extract target miRNAs in EVs from plasma based on Fe₃O₄@TiO₂ beads with high affinity and capture efficiency. We combined a heat-lysis method for quick and simple EV miRNA extraction and detection. The results indicated that our method has more RNA yield than TRIzol or a commercial kit and could complete EV enrichment and miRNA extraction in 30 min. Through the detection of miRNA-21, healthy people and lung cancer patients were distinguished, which verified the possibility of the application in clinical detection. The automated isolation technology for EV miRNA has good repeatability and high throughput, with great application potential in clinical diagnosis.

Novel MSH6 mutation predicted metastasis in eyelid and periocular squamous cell carcinoma

BACKGROUND

Our previous research revealed the relative local aggressiveness of eyelid and periocular squamous cell carcinoma (EPSCC), but its distinct genetic characteristics involved remain unknown.

OBJECTIVES

We conducted this study based on next-generation sequencing to identify the genetic distinctiveness of EPSCC and damaging mutations for possible etiology and poor prognosis.

METHODS

We performed sequencing using a 556-gene panel (smartonco) in 48 EPSCCs. Cox hazards model was applied to explore mutated genes that increase risk of metastasis and death. Pathogenesis of the mutations was predicted by sequence alignment algorithms.

RESULTS

The most commonly mutated genes were KMT2C (N=17, 35%), LRP1B (N=14, 29%), KMT2D (N=12, 25%), PTCH1(N=10, 21%) and TP53(N=10, 21%). DNA mismatch repair (MMR) genes (42%) like MSH6(19%) and MLH3(12%) were among the most frequently mutated genes. Cell cycle regulators including TP53(21%) and CDKN2A (10%) were less frequently mutated than in other squamous cell carcinomas (SCCs). Ultra violet exposure, MMR deficiency and aging were the main etiology. Of note, KMT2C has a deleterious mutation hotspot. Patients burdened with MSH6 mutation has a higher risk of overall metastasis (P=0.045, HR=5.165) and nodal metastasis (P=0.022, HR=14.038). Moreover, a hotspot mutation MSH6^E52A brought an even higher risk of nodal metastasis (P=0.011, HR=18.745).

CONCLUSIONS

EPSCCs displayed a unique mutation profile from cutaneous SCCs and mucosal SCCs. We have identified novel damaging mutations in epigenetic regulators like KMT2C boosted early onset of EPSCCs in addition to UVR, aging or MMR deficiency. And malfunction of MMR genes worsened prognosis.

Morphological classification and measurement of the glenoid cavity using three-dimensional reconstruction in a Chinese population

BACKGROUND

The purpose of this study was to examine the various shapes and record the morphometric data of the glenoid cavity in a Chinese population.

MATERIALS AND METHODS

A total of 501 scapulae, 247 left and 254 right, were analyzed. We classified the shape of the glenoid cavity as type Ⅰ (pear-shaped), type Ⅱ (oval-shaped), type Ⅲ (teardrop-shaped), type Ⅳ (calabash-shaped) or type Ⅴ (inverted comma-shaped). Four defined parameters, the superior-inferior glenoid diameter (AB), upper anterior-posterior glenoid diameter (CD), lower anterior-posterior glenoid diameter (EF) and glenoid index (GI), were measured, and five shapes were classified via three-dimensional reconstruction.

RESULTS

The mean AB, CD, EF and GI values of the glenoid were 3.51±0.41 cm, 1.95±0.28 cm, 2.60±0.34 cm, and 1.35±0.12 cm, respectively. The AB value of type Ⅱ glenoid cavities was significantly smaller than that of type Ⅰ and Ⅲ glenoid cavities (P<0.05), but the GI value of type Ⅱ glenoid cavities was larger than that of type Ⅲ cavities (P<0.05). The CD value showed a difference between type Ⅰ and type Ⅲ glenoid cavities (P<0.05). For the EF parameter, the values of type Ⅲ glenoid cavities were significantly larger than those of type Ⅰ and Ⅱ glenoid cavities (P<0.05).

CONCLUSIONS

Measuring and observing the variety of shapes and sizes of the glenoid cavity in Chinese people is conducive to for better understand its morphological features. This information can also guide surgeons in the design and selection of suitable prostheses for total shoulder arthroplasty in the Chinese population in order to reduce postoperative complications.

[Retrospective analysis on 77 cases of T4b hypopharyngeal carcinoma treated by non-surgical treatments]

Objective: To analyze the effectiveness, safety and factors influencing the clinical prognosis of patients with hypopharyngeal carcinoma in T4b by nonsurgical treatments. Methods: The clinical data of 77 patients with T4b hypopharyngeal cancer treated in the College of Otolaryngology Head and Neck Surgery of the Chinese People's Liberation Army General Hospital from January 2010 to June 2021 were analyzed retrospectively. All were males, aged(57.0±8.0)years old. Patients were treated with induction chemotherapy plus concurrent chemoradiotherapy. Kaplan Meier survival analysis was used to compare the effects of different factors on prognosis. Adverse reactions during treatments and the causes of death were analyzed. Results: 98.7% of 77 patients with T4b hypopharyngeal cancer completed the chemotherapy plan and 94.8% completed the radiotherapy plan. The most common adverse reactions were grade 2 radiation oral mucositis (50/77, 64.9%) and grade 2 leukopenia (50/77, 64.9%). The incidence of grade 3 severe hoarseness was 7.8% (6/77), one patient (1.3%) underwent gastrostomy due to dysphagia, and pronunciation and swallowing function were effectively preserved in other patients. The overall survival rate was 71.9% at 1 year, 45.6% at 3 years and 29.7% at 5 years. The location of tumor, the presence of liquefaction necrosis in tumor, the use of molecular targeted drugs and the approach of radiotherapy were independent factors,each of which that affected the prognosis of T4b patients with advanced hypopharyngeal cancer [HR (95%CI) were 1.867(1.085-3.213), 3.018 (1.437-6.335), 0.372 (0.181-0.764) and 2.158 (1.015-4.588), respectively, P<0.05]. The two leading causes of death with high incidence were disease recurrence (12/32, 37.5%) and cervical large vessel rupture and hemorrhage (11/32, 34.4%). Conclusions: Non-surgical comprehensive treatment offers a high laryngeal preservation rate in patients with T4b hypopharyngeal cancer. The location of tumor, the liquefaction necrosis within tumor, the use of molecular targeted drugs, and the approach of radiotherapy are independent prognostic factors.

Eggs Consumption in Relation to Lower Risk of Cognitive Impairment in Elderly: Findings from a 6-Year Cohort Study

OBJECTIVES

To evaluate the longitudinal association of eggs consumption with cognitive function in Chinese elderly.

DESIGN

Prospective cohort study.

PARTICIPANTS

9028 participants aged ≥60 years from Zhejiang Ageing and Health Cohort Study without cognitive impairment at baseline survey.

MEASUREMENTS

Cognitive function was assessed through the Mini-Mental State Examination (MMSE) at baseline and three waves of follow-up (2015, 2016, and 2019-2020). Data on eggs consumption was collected in the diet habits section within the questionnaire at baseline. Log-binomial regression models with the Generalized Estimating Equations, controlled for an extensive range of potential confounders, were used to evaluate the association and estimate relative risks (RRs).

RESULTS

After 6 years of follow-up, 3266 (36.18%) participants were indicated as cognitive impairment by MMSE at least once. Compared with non-consumers or less-than-weekly consumers, participants consuming 0.1-2.9 eggs/week and 3.0-5.9 eggs/week had 18% (RR=0.82, 95%CI 0.76-0.89) and 9% (RR=0.91, 95%CI 0.84-0.99) lower risks of cognitive impairment respectively, whereas no association was found in those consuming ≥6.0 eggs/week (P=0.32). Moreover, infrequent lower-quantity consumption (1-2 days/week and 0.1-1.9 eggs/day), infrequent higher-quantity consumption (1-2 days/week and ≥2.0 eggs/day), and frequent lower-quantity consumption (≥3 days/week and 0.1-1.9 eggs/day) were associated with better cognitive performance, whereas null association was found among frequent higher-quantity consumers (≥3 days/week and ≥2.0 eggs/day). The sensitivity analyses yielded consistent results to the main analysis.

CONCLUSION

Limited eggs consumption is prospectively related to a lower risk of cognitive impairment in Chinese elderly.

Band-selective Holstein polaron in Luttinger liquid material A0.3MoO3 (A = K, Rb)

(Quasi-)one-dimensional systems exhibit various fascinating properties such as Luttinger liquid behavior, Peierls transition, novel topological phases, and the accommodation of unique quasiparticles (e.g., spinon, holon, and soliton, etc.). Here we study molybdenum blue bronze A_0.3MoO₃ (A = K, Rb), a canonical quasi-one-dimensional charge-density-wave material, using laser-based angle-resolved photoemission spectroscopy. Our experiment suggests that the normal phase of A_0.3MoO₃ is a prototypical Luttinger liquid, from which the charge-density-wave emerges with decreasing temperature. Prominently, we observe strong renormalizations of band dispersions, which are recognized as the spectral function of Holstein polaron derived from band-selective electron-phonon coupling in the system. We argue that the strong electron-phonon coupling plays an important role in electronic properties and the charge-density-wave transition in blue bronzes. Our results not only reconcile the long-standing heavy debates on the electronic properties of blue bronzes but also provide a rare platform to study interesting excitations in Luttinger liquid materials.

[Transcranial sonographic characteristics of Parkinson's disease with symptoms of restless legs syndrome]

Objective: To evaluate the transcranial sonographic characteristics in patients with Parkinson's disease (PD) with symptoms of restless legs syndrome (RLS). Methods: Patients with diagnosis of definite PD from the Second Affiliated Hospital of Soochow University and 3 other participating hospitals between September 2018 and December 2019 were consecutively enrolled. Concurrent RLS symptoms were determined using Non-motor Symptoms Questionnaire. Transcranial sonography (TCS) and clinical assessments were performed during the same time and the related variables were compared between the two groups using t-test, non-parametric test, Chi-square test and Spearman correlation analysis, respectively. Results: Among 349 patients with PD, the prevalence of RLS symptoms was 22.6%. Compared to patients without RLS symptoms, those with RLS had longer disease duration (43.0 (24.0, 91.0) months vs 37.0 (20.0, 60.0) months, P<0.05) and higher Hoehn-Yahr stage (2.5 (2.0, 3.0) vs 2.0 (1.5, 2.5), P<0.01).TCS revealed that patients with RLS symptoms were more likely to have abnormality in the raphe nucleus (21.50% vs 7.78%, χ²=15.9, P<0.001) and increased third ventricle width ((6.22±1.97) mm vs (5.16±1.90) mm, P<0.001). No significant differences were found regarding parameters of substantia nigra. Conclusions: Concurrent RLS symptoms are common in PD patients. Abnormal echogenicity of raphe nucleus and increased third ventricle width could be characteristics of TCS in PD patients with RLS symptoms.

AB0343 THE CHARACTERISTICS OF T CELLS IN SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS WITH ANXIETY BASED ON MACHINE LEARNING

Background:

Systemic lupus erythematosus (SLE) is an autoimmune disease, the immune system of patients to be disordered, especially in T cell subsets1. They were prone to mental diseases, anxiety particularly, which lead to suicide2. The recent study had reported that CD4+ T cells in the peripheral blood played the key role in like anxiety behavior of mice3. Although there showed that the level of serum TNF-α in SLE patients with anxiety was higher than without anxiety4, finding the important special mediators especially in T cell subsets was still necessary for the prevention of anxiety in SLE patients.

Objectives:

In total, 108 SLE patients, which met the diagnostic criteria of the American Society of rheumatology (v1997), were enrolled in this study from Affilliated Hospital of Nantong University, China. Exclusion criteria included other autoimmune diseases and active infection (including hepatitis B or C virus, Epstein-Barr virus, human immunodeficiency virus or Mycobacterium tuberculosis infection).

Methods:

We surveyed the abundance of 74 immune cell subpopulations from 108 SLE patients using flow cytometry, and investigated their differences between patients with and without anxiety (24 versus 84). Moreover, machine learning including Lasso regression, Random forest (RF) and Sparsity partial least squares discriminant analysis (sPLS-DA) was employed to build models and futher selected important features for the classification of SLE patients with anxiety.

Results:

SLE patients with anxiety showed higher body mass index (BMI) and lower quality of life. In their peripheral blood, the proportion of internal cell subsets composition of Th cell and Treg cells changed. By machine learning, we finally found that BMI and PD1-CD28- Treg played important rules to developing lupus anxiety.

Conclusion:

In this study, machine learning was applied to build models to select the most important T cell subset in SLE patients with anxiety. These findings suggested that BMI and imbalance of PD1-CD28- Treg containing effector memory Treg cells and effector Treg cells mostly played important roles in the development of SLE anxiety.

Disclosure of Interests:

None declared

OP0073 SINGLE-CELL TRANSCRIPTOMICS UNCOVERS DEFECTIVE BONE MARROW EARLY B CELL DEVELOPMENT IN A SUBSET OF LUPUS PATIENTS ASSOCIATED WITH AGGRAVATED INFLAMMATION

Background:

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that occurs when the body’s immune system attacks own tissues and organs. B cells play a central role in SLE pathogenesis by producing autoantibodies as well as antibody-independent functions. Peripheral B cell abnormality is well known in lupus patients such as expansions of plasmablasts and atypical memory B cells, which are associated with active diseases. However, little is known about the B cell development in the bone marrow of lupus patients.

Objectives:

We conduct this survey to explore the disorder of the B cell development in the bone marrow of lupus patients.

Methods:

In this study, we have performed the scRNASeq to profile the bone marrow B cell compartment in lupus patients and healthy donors.

Results:

We identified that in a subset of lupus patients, the early B cells (proB and preB cells) were strongly decreased, which were confirmed by flow cytometry in an expanded cohort. Furthermore, bone marrow B cells from these patients showed a strong proinflammatory signature revealed by pathway analysis. Interestingly, BCR repertoire analysis showed that the IGHV-4-34 was highly enriched in these patients, indicating an enhanced B cell tolerance defect. Finally, a panel of proinflammatory cytokines (TNF-a, IL-1a, IL-12p70, IFN-g, et al.) were strongly increased in the bone marrow plasma of these patients compared with early B normal patients and healthy donors, confirming a localized proinflammatory microenvironment.

Conclusion:

Altogether, the current study has revealed that a defective early B cell development in lupus patients is associated with a more severe B cell tolerance defect and aggravated inflammation, which may shed new light on developing novel therapies by targeting relevant pathways.

References:

[1]Min Wang, Hua Chen, Jia Qiu, et al. Antagonizing miR-7 suppresses B cell hyperresponsiveness and inhibits lupus development. J Autoimmun 2020.

[2]A M Jacobi, D M Goldenberg, F Hiepe, et al. Differential effects of epratuzumab on peripheral blood B cells of patients with systemic lupus erythematosus versus normal controls. Ann Rheum Dis, 2008.

Acknowledgements:

This work was funded by Special project of clinical medicine of Nantong University (Grant/Award number: 2019LQ001), National Natural Science Foundation of China (Grant/Award number: 81671616, 81871278 and 82071838).

Disclosure of Interests:

None declared

POS0002 PI16 REPRESSES FOXP3 EXPRESSION IN T REGULATORY CELLS AND EXACERBATES AUTOIMMUNE ARTHRITIS VIA INHIBITING THE K48-LINKED POLYUBIQUITIN DEGRADATION OF BMI-1

Background:

Regulatory T cells (Tregs) play an essential role in maintaining self-tolerance and immune homeostasis. Abnormalities in the quantity or function of Treg cells are believed in RA patients, contributing to the inability to suppress autoimmunity and proinflammatory cytokines. Forkhead box P3 (Foxp3) is a crucial transcription factor for the development and differentiation of Tregs. How Tregs lose Foxp3 expression under inflammatory milieu remains largely unknown. Peptidase inhibitor 16 (PI16) is a member of the CAP (Cysteine-rich secretory proteins, Antigen 5, and Pathogenesis-related 1) protein family and its function are largely poor understood. In a genome-wide expression profiling study for identifying human Foxp3 target genes revealed PI16 was expressed on the cell surface of >80% of resting human CD25+ Foxp3+ Tregs. In the inflamed joint of juvenile idiopathic arthritis revealed a low number of PI16+ Tregs but high number of Th17 cells. However, little is known the function role of PI16 on Tregs or on RA development.

Objectives:

To investigate the role of peptidase inhibitor 16 (PI16) on the key T regulatory (Tregs) cells transcription factor Foxp3 expression and on the development of autoimmune arthritis.

Methods:

The expression of PI16 in blood, synovial fluid, inflamed joints were examined in Rheumatoid arthritis (RA) patients and in arthritic mice. Arthritis symptom, histological features and Foxp3 expression in PI16 transgenic (PI16Tg) arthritic mice were examined. Posttranslational mechanisms on PI16-mediated Foxp3 expression were analyzed. The specific role PI16 on Foxp3 expression was validated in conditional knockout (KO) mice.

Results:

The expression of PI16 was significantly increased in PBMC, serum, synovial tissue from RA patients or arthritic mice compared with controls. PI16Tg arthritic mice exhibited obvious inflammation, synovial hyperplasia and articular cartilage destruction in the joints compared with those in wild-type mice (WT) arthritic mice.

Foxp3 is downregulated in splenic T cells and synovial tissue from PI16Tg arthritic mice. Naïve T cells derived from PI16Tg arthritic mice showed the decreased capacity to differentiate into Tregs. Polycomb-group (PcG) proteins complex molecule of Bmi-1 was significant increase in Tregs and joint tissue from PI16Tg arthritic mice. A direct interaction between 1-95AA domains of PI16 and 169 and 436 domains of Bmi-1 in Tregs promoter was observed. The binding of PI16 with Bmi-1 in the Foxp3 promoter inhibit the K48-linked polyubiquitin degradation of Bmi-1 at lysine site 72 and 153 region, which prompts the repressive histone modification of H3K27me3 and H2AK119ub, and inhibits the active histone modification of H3K4me3. Furthermore, conditional knockout of PI16 in Tregs retarded Foxp3 loss and blunted disease progression in experimental arthritis.

Conclusion:

PI16 represses Foxp3 expression by mediating histone modification via inhibiting K48-linked polyubiquitin degradation of Bmi-1 in Foxp3 promoter, contributing to disease progression in arthritic mice.

Disclosure of Interests:

None declared.