Extrasynaptic GABAA receptors in central medial thalamus mediate anesthesia in rats

Neuronal depression in the thalamus underlies anesthetic-induced loss of consciousness, while the precise sub-thalamus nuclei and molecular targets involved remain to be elucidated. The present study investigated the role of extrasynaptic GABAA receptors in the central medial thalamic nucleus (CM) in anesthesia induced by gaboxadol (THIP) and diazepam (DZP) in rats. Local lesion of the CM led to a decrease in the duration of loss of righting reflex induced by THIP and DZP. CM microinjection of THIP but not DZP induced anesthesia. The absence of righting reflex in THIP-treated rats was consistent with the increase of low frequency oscillations in the delta band in the medial prefrontal cortex. CM microinjection of GABAA receptor antagonist SR95531 significantly attenuated the anesthesia induced by systemically-administered THIP, but not DZP. Moreover, the rats with declined expression of GABAA receptor δ-subunit in the CM were less responsive to THIP or DZP. These findings explained a novel mechanism of THIP-induced loss of consciousness and highlighted the role of CM extrasynaptic GABAA receptors in mediating anesthesia.

Sub-region based radiomics analysis for prediction of isocitrate dehydrogenase and telomerase reverse transcriptase promoter mutations in diffuse gliomas

AIM

To enhance the prediction of mutation status of isocitrate dehydrogenase (IDH) and telomerase reverse transcriptase (TERT) promoter, which are crucial for glioma prognostication and therapeutic decision-making, via sub-regional radiomics analysis based on multiparametric magnetic resonance imaging (MRI).

MATERIALS AND METHODS

A retrospective study was conducted on 401 participants with adult-type diffuse gliomas. Employing the K-means algorithm, tumours were clustered into two to four subregions. Sub-regional radiomics features were extracted and selected using the Mann-Whitney U-test, Pearson correlation analysis, and least absolute shrinkage and selection operator, forming the basis for predictive models. The performance of model combinations of different sub-regional features and classifiers (including logistic regression, support vector machines, K-nearest neighbour, light gradient boosting machine, and multilayer perceptron) was evaluated using an external test set.

RESULTS

The models demonstrated high predictive performance, with area under the receiver operating characteristic curve (AUC) values ranging from 0.918 to 0.994 in the training set for IDH mutation prediction and from 0.758 to 0.939 for TERT promoter mutation prediction. In the external test sets, the two-cluster radiomics features and the logistic regression model yielded the highest prediction for IDH mutation, resulting in an AUC of 0.905. Additionally, the most effective predictive performance with an AUC of 0.803 was achieved using the four-cluster radiomics features and the support vector machine model, specifically for TERT promoter mutation prediction.

CONCLUSION

The present study underscores the potential of sub-regional radiomics analysis in predicting IDH and TERT promoter mutations in glioma patients. These models have the capacity to refine preoperative glioma diagnosis and contribute to personalised therapeutic interventions for patients.

Effects of olanzapine on hippocampal CA3 and the prefrontal cortex local field potentials

Olanzapine is an antipsychotic drug applied in psychiatry to treat psychoses, especially schizophrenia and schizoaffective disorders with similar or better improvement than haloperidol and risperidone in the treatment of depressive and negative symptoms. The effect of olanzapine on neural synchrony remains to be explored. We investigated the effects of olanzapine on gamma oscillations in the CA3 region of the hippocampus and frontal association cortex. Olanzapine reduced carbachol (CCh)-induced gamma oscillation power in CA3 slice and gamma oscillation power in the frontal association cortex in vivo. The power of theta oscillations was increased in the presence of olanzapine. The phase amplitude coupling of theta and gamma wave was strengthened by the administration of olanzapine in the frontal association cortex in vivo. Taken together, these results show that olanzapine modulates local field potential and the neuronal activity.

Modulation of DOM-Induced Head-Twitch Response by mGluR2 Agonist/Inverse Agonist is Associated with 5-HT2AR-Mediated Gs Signaling Pathway

Hallucinogenic 5-HT2A receptor (5-HT2AR) agonists-induced head-twitch response (HTR) is regulated by Gs signaling pathway. Formation of heterodimers between 5-HT2AR and metabotropic glutamate mGlu2 receptor (mGluR2) is essential for the hallucinogenic 5-HT2AR agonist-induced HTR. In order to investigate the effects of mGluR2 agonists and inverse agonists on hallucinogenic 5-HT2AR agonists DOM-induced HTR, C57BL/6 mice were pretreated with mGluR2 agonists (LY379268, LY354740, LY404039) or the inverse agonist LY341495, and the HTR was manually counted after administering DOM immediately. IP-One (IP1) HTRF assay and cAMP assay were performed to evaluate the effect of LY341495 or LY354740 on DOM-induced Gq and Gs activation in Human Embryonic Kidney-293 (HEK-293) T-type cells co-expressing 5-HT2AR and mGluR2. The results showed that DOM-induced HTR in mice was dose-dependently inhibited by LY379268, LY354740, and LY404039, while it was dose-dependently enhanced by LY341495. Moreover, LY341495 reversed the inhibitory effect of LY354740 on DOM-induced HTR. In HEK-293T cells co-expressing 5-HT2AR and mGluR2, DOM-induced cAMP level was decreased by LY354740 and increased by LY341495, but DOM-induced IP1 level was not regulated by LY354740 or LY341495. The regulation of DOM-induced HTR by mGluR2 agonists and inverse agonists is closely related to 5-HT2AR-mediated Gs signaling pathway. In HEK-293T cells co-expressing 5-HT2AR and mGluR2 A677S/A681P/A685G mutant (mGluR2 3 A mutant), DOM-induced cAMP level was not regulated by LY354740, but was significantly enhanced by LY341495. The 5-HT2AR/mGluR2 heterodimers is critical for DOM-induced HTR and cAMP level, both of which are inhibited by mGluR2 agonists and enhanced by mGluR2 inverse agonists.

Novel Scaffold Agonists of the α2A Adrenergic Receptor Identified via Ensemble-Based Strategy

The α2A adrenergic receptor (α2A-AR) serves as a critical molecular target for sedatives and analgesics. However, α2A-AR ligands with an imidazole ring also interact with an imidazoline receptor as well as other proteins and lead to undesirable effects, motivating us to develop more novel scaffold α2A-AR ligands. For this purpose, we employed an ensemble-based ligand discovery strategy, integrating long-term molecular dynamics (MD) simulations and virtual screening, to identify new potential α2A-AR agonists with novel scaffold. Our results showed that compounds SY-15 and SY-17 exhibited significant biological effects in the preliminary evaluation of protein kinase A (PKA) redistribution assays. They also reduced levels of intracellular cyclic adenosine monophosphate (cAMP) in a dose-dependent manner. Upon treatment of the cells with 100 μM concentrations of SY-15 and SY-17, there was a respective decrease in the intracellular cAMP levels by 63.43% and 53.83%. Subsequent computational analysis was conducted to elucidate the binding interactions of SY-15 and SY-17 with the α2A-AR. The binding free energies of SY-15 and SY-17 calculated by MD simulations were -45.93 and -71.97 kcal/mol. MD simulations also revealed that both compounds act as bitopic agonists, occupying the orthosteric site and a novel exosite of the receptor simultaneously. Our findings of integrative computational and experimental approaches could offer the potential to enhance ligand affinity and selectivity through dual-site occupancy and provide a novel direction for the rational design of sedatives and analgesics.

Clinical consequence of vessel perforations during endovascular treatment of acute ischemic stroke

PURPOSE

Endovascular treatment (EVT) of acute ischemic stroke can be complicated by vessel perforation. We studied the incidence and determinants of vessel perforations. In addition, we studied the association of vessel perforations with functional outcome, and the association between location of perforation on digital subtraction angiography (DSA) and functional outcome, using a large EVT registry.

METHODS

We included all patients in the MR CLEAN Registry who underwent EVT. We used DSA to determine whether EVT was complicated by a vessel perforation. We analyzed the association with baseline clinical and interventional parameters using logistic regression models. Functional outcome was measured using the modified Rankin Scale at 90 days. The association between vessel perforation and angiographic imaging features and functional outcome was studied using ordinal logistic regression models adjusted for prognostic parameters. These associations were expressed as adjusted common odds ratios (acOR).

RESULTS

Vessel perforation occurred in 74 (2.6%) of 2794 patients who underwent EVT. Female sex (aOR 2.0 (95% CI 1.2-3.2)) and distal occlusion locations (aOR 2.2  (95% CI 1.3-3.5)) were associated with increased risk of vessel perforation. Functional outcome was worse in patients with vessel perforation (acOR 0.38 (95% CI 0.23-0.63)) compared to patients without a vessel perforation. No significant association was found between location of perforation and functional outcome.

CONCLUSION

The incidence of vessel perforation during EVT in this cohort was low, but has severe clinical consequences. Female patients and patients treated at distal occlusion locations are at higher risk.

[Analysis on the use of HIV post-exposure prophylaxis and related factors in men who have sex with men in Qingdao]

Objective: To understand the use of post-exposure prophylaxis (PEP) and analyze related factors among men who have sex with men (MSM) in Qingdao, and provide a reference for the AIDS prevention and control in this population. Methods: A cross-sectional survey conducted from April 2022 to February 2023. Relying on MSM social groups in Qingdao, a snowball sampling method was applied to recruit research subjects who met the inclusion criteria of age ≥18 years old, having had homosexual anal or oral sex in the past six months, and HIV-negative or infection status unknown. The sample size was estimated at 566. Data on demographic characteristics, sexual behavior characteristics, PEP use, and others of the research subjects was collected through on-site questionnaires. The logistic regression model was used to analyze the factors associated with using PEP. Results: A total of 811 participants were recruited, mainly aged 25-34 (53.6%, 435/811), unmarried (74.7%, 606/811), with an average monthly income of ≥5 000 yuan (52.2%, 423/811), and having lived in Qingdao for ≥10 years (75.6%, 613/811). The proportion of those who knew the HIV status of their sexual partners in the last six months was 67.1% (544/811), and those with HIV-positive partners were 3.6% (29/811). In the last six months, the proportion of participants who had group sex (86.4%, 701/811), unprotected anal sex (98.2%, 796/811), and use of club drugs (80.3%, 651/811) was high. Moreover, 28.4% (230/811) had used PEP. The multivariate logistic regression analysis showed that the factors related to the use of PEP included divorced or widowed (aOR=5.46,95%CI:1.96-15.17), average monthly income ≥5 000 yuan (aOR=2.04,95%CI:1.44-2.89), same-sex sexual orientation (aOR=0.40,95%CI:0.22-0.71), having HIV-positive sexual partners in the last six months (aOR=2.54,95%CI:1.13-5.71) and having been tested for HIV ≥3 times in the last six months (aOR=1.46,95%CI:1.04-2.06). Conclusions: The prevalence of risk behaviors among MSM in Qingdao was high, and the use of PEP was low. In the future, it is essential to increase HIV/AIDS prevention education among MSM, promote MSM to know the HIV status of their sexual partners, and reduce the prevalence of risk behaviors among this population. Additionally, explore medical insurance reimbursement plans for PEP to reduce utilization costs and promote the use of PEP by MSM after HIV exposure occurs as soon as possible.

Gβγ subunit inhibitor decreases DOM-induced head twitch response via the PLCβ/IP3/Ca2+/ERK and cAMP signaling pathways

AIMS

(-)-2,5-dimethoxy-4-methylamphetamine (DOM) induces the head-twitch response (HTR) primarily by activating the serotonin 5-hydroxytryptamine 2A receptor (5-HT2A receptor) in mice. However, the mechanisms underlying 5-HT2A receptor activation and the HTR remain elusive. Gβγ subunits are a potential treatment target in numerous diseases. The present study investigated the mechanism whereby Gβγ subunits influence DOM-induced HTR.

MAIN METHODS

The effects of the Gβγ inhibitor 3',4',5',6'-tetrahydroxyspiro[2-benzofuran-3,9'-xanthene]-1-one (gallein) and antagonistic peptide βARKct (β-adrenergic receptor kinase C-terminal fragment) on DOM-induced HTR were studied via an HTR test. The activation of the phospholipase C β (PLCβ)/inositol triphosphate (IP3)/calcium (Ca2+) signaling pathway and extracellular signal-regulated kinase (ERK) following Gβγ subunit inhibition was detected by western blotting, Homogeneous Time-Resolved Fluorescence (HTRF) inositol phosphate (IP1) assay and Fluorometric Imaging Plate Reader (FLIPR) calcium 6 assay. The Gβγ subunit-mediated regulation of cyclic adenosine monophosphate (cAMP) was assessed via a GloSensor™ cAMP assay.

KEY FINDINGS

The Gβγ subunit inhibitors gallein and βARKct reduced DOM-induced HTR in C57BL/6J mice. Like the 5-HT2A receptor-selective antagonist (R)-[2,3-di(methoxy)phenyl]-[1-[2-(4-fluorophenyl)ethyl]piperidin-4-yl]methanol (M100907), gallein inhibited PLCβ phosphorylation (pPLCβ), IP1 production, Ca2+ transients, ERK1/2 phosphorylation (pERK1/2) and cAMP accumulation induced by DOM in human embryonic kidney (HEK) 293T cells stably or transiently transfected with the human 5-HT2A receptor. Moreover, PLCβ protein inhibitor 1-[6-[[(8R,9S,13S,14S,17S)-3-methoxy-13-methyl-6,7,8,9,11,12,14,15,16,17-decahydrocyclopenta[a]phenanthren-17-yl]amino]hexyl]pyrrole-2,5-dione (U73122) (10 nmol/mouse), intracellular Ca2+ blocker 6-[6-[6-[5-acetamido-4,6-dihydroxy-2-(sulfooxymethyl)oxan-3-yl]oxy-2-carboxy-4-hydroxy-5-sulfooxyoxan-3-yl]oxy-2-(hydroxymethyl)-5-(sulfoamino)-4-sulfooxyoxan-3-yl]oxy-3,4-dihydroxy-5-sulfooxyoxane-2-carboxylic acid (heparin) (5 nmol/mouse), L-type Ca2+ channel blocker 3-O-(2-methoxyethyl) 5-O-propan-2-yl 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate (nimodipine) (4 mg/kg), mitogen extracellular regulating kinase 1/2 (MEK1/2) inhibitor (Z)-3-amino-3-(4-aminophenyl)sulfanyl-2-[2-(trifluoromethyl)phenyl]prop-2-enenitrile (SL327) (30 mg/kg), and Gαs protein selective antagonist 4,4',4″,4‴-(Carbonylbis-(imino-5,1,3-benzenetriylbis(carbonylimino)))tetrakisbenzene-1,3-disulfonic acid (NF449) (10 nmol/mouse) reduced DOM-induced HTR in C57BL/6J mice.

SIGNIFICANCE

The Gβγ subunits potentially mediate the HTR after 5-HT2A receptor activation via the PLCβ/IP3/Ca2+/ERK1/2 and cAMP signaling pathways. Inhibitors targeting the Gβγ subunits potentially inhibit the hallucinogenic effects of 5-HT2A receptor agonists.

Clinical application of laparoscopic continuous interposition jejunostomy with double-tract anastomosis and esophagogastric anastomosis: a retrospective study

OBJECTIVE

The aim of this study was to compare the early clinical outcomes of laparoscopic-assisted proximal gastrectomy with continuous interposition of jejunal cis-peristaltic dual-channel anastomosis and esophagogastric anastomosis.

PATIENTS AND METHODS

A retrospective analysis of 130 patients who underwent laparoscopic-assisted radical resection of proximal gastric cancer in the Department of Gastrointestinal Surgery at the Affiliated Hospital of Chengde Medical College between June 2018 and October 2022 was conducted. Continuous interposition jejunal double-channel anastomosis (double-tract anastomosis) was used in 71 patients and esophagogastric anastomosis (esophagogastrostomy) in 59 patients. The basic clinical data, preoperative and postoperative clinical test indexes, postoperative complications and improvement of symptoms compared to preoperative ones, basic nutritional status and Visick classification of esophageal reflux symptoms at 6 months after surgery were compared between the two groups. Postoperative contrast images of patients in the continuous interposition jejunal double-tract group were collected and analyzed for the ratio of contrast agent remaining in the stomach to that remaining in the small intestinal channel.

RESULTS

A total of 130 cases meeting the criteria were included in this study, including 71 cases involving the double-tract (DT) anastomosis method and 59 cases involving the esophagogastrostomy (EG) anastomosis method. There was no significant difference in preoperative information and perioperative safety between the two groups. Visick score of the DT group was significantly better than that of the EG group.

CONCLUSIONS

Double-tract jejunal anastomosis can effectively improve esophageal reflux symptoms after proximal gastrectomy. At the same time, its anastomotic method also improves the nutritional status in the short term compared to the esophagogastric anastomosis and is a more ideal procedure for reconstructing the digestive tract after proximal gastrectomy.

Acute psilocybin increased cortical activities in rats

Psilocybin, a naturally occurring hallucinogenic component of magic mushrooms, has significant psychoactive effects in both humans and rodents. But the underlying mechanisms are not fully understood. Blood-oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) is a useful tool in many preclinical and clinical trials to investigate psilocybin-induced changes of brain activity and functional connectivity (FC) due to its noninvasive nature and widespread availability. However, fMRI effects of psilocybin on rats have not been carefully investigated. This study aimed to explore how psilocybin affects resting-state brain activity and FC, through a combination of BOLD fMRI and immunofluorescence (IF) of EGR1, an immediate early gene (IEG) closely related to depressive symptoms. Ten minutes after psilocybin hydrochloride injection (2.0 mg/kg, i.p.), positive brain activities were observed in the frontal, temporal, and parietal cortex (including the cingulate cortex and retrosplenial cortex), hippocampus, and striatum. And a region-of-interest (ROI) -wise FC analysis matrix suggested increased interconnectivity of several regions, such as the cingulate cortex, dorsal striatum, prelimbic, and limbic regions. Further seed-based analyses revealed increased FC of cingulate cortex within the cortical and striatal areas. Consistently, acute psilocybin increased the EGR1 level throughout the brain, indicating a consistent activation thought the cortical and striatal areas. In conclusion, the psilocybin-induced hyperactive state of rats is congruent to that of humans, and may be responsible for its pharmacological effects.

[Progress in research on HIV self-testing and associated factors among men who have sex with men in China]

HIV testing is the first step in HIV prevention and control, the rate of HIV infection is high and the rate of HIV testing is low among men who have sex with men (MSM) in China. HIV self-testing provides MSM with a new choice and plays a vital role in expanding the coverage of HIV testing in this population. This paper reviews HIV self-testing and associated factors among MSM in China and provides a reference for promoting HIV self-testing in this population.

Effects of Ketanserin, M100907 and Olanzapine on hallucinogenic like action induced by 2,5-dimethoxy-4-methylamphetamine

2,5-dimethoxy-4-methylamphetamine (DOM) is a kind of hallucinogen of phenylalkylamine. Psychedelic effects mainly include audiovisual synesthesia, complex imagery, disembodiment etc. that can impair control and cognition leading to adverse consequences such as suicide. By now, there are no specific drugs regarding the management of classic hallucinogen use clinically. We evaluated the effects of three 5-HT 2A receptor antagonists ketanseirn, M100907 and olanzapine on hallucination-like behavior in therapeutic and preventive administration with male C57BL/6J mice. Two models were used to evaluate the therapeutic potential of antagonists, one is head-twitch response (HTR) and the other is locomotion. Effects of ketanserin, M100907 and olanzapine on DOM-induced HTR were studied in preventive and therapeutic administration, respectively. In the preventive administration, the ID 50 values of ketanseirn, M100907 and olanzapine were 0.4 mg/kg, 0.005 mg/kg and 0.25 mg/kg. In the therapeutic administration, the ID 50 values of ketanseirn, M100907 and olanzapine were 0.04 mg/kg, 0.005 mg/kg and 0.03 mg/kg. Secondly, locomotor activity induced by DOM was performed to further evaluate the efficacy of three compounds. In locomotion, M100907(0.005 mg/kg) whenever in preventive or therapeutic administration, reduced the increase of movement distance induced by DOM. Although ketanserin (0.4 mg/kg) in the preventive administration also decreased the movement distance induced by DOM, it was alone administrated to influence the locomotor activity. Through HTR and locomotion, we compared the efficacy and latent side effects of ketanserin, M100907 and olanzapine against hallucinogenic like action induced by DOM. Our study provided additional experimental evidence on specific therapeutic drugs against hallucinogenic behavior induce by representative hallucinogen DOM.

Rearing behaviour in the mouse behavioural pattern monitor distinguishes the effects of psychedelics from those of lisuride and TBG

Psychedelics alter consciousness and may have potential for drug development. As psychedelics are likely therapeutically active, it is important to study their effects and mechanisms using preclinical models. Here, we examined the effects of phenylalkylamine and indoleamine psychedelics on locomotor activity and exploratory behaviour using the mouse Behavioural Pattern Monitor (BPM). DOM, mescaline, and psilocin reduced locomotor activity at high doses and influenced rearings, an exploratory behaviour, in a characteristic inverted U-shaped dose-response function. Pretreatment with the selective 5-HT_2A antagonist M100907 reversed the drug-induced alterations in locomotor activity, rearings, and jumps after systemic administration of DOM at low doses. However, holepoking at the full range of doses tested was not blocked by M100907. Administration of the hallucinogenic 5-HT_2A agonist 25CN-NBOH induced striking similarities in response to that to psychedelics; these alterations were significantly diminished by M100907, whereas the putatively non-hallucinogenic 5-HT_2A agonist TBG did not affect locomotor activity, rearings, or jumps at the most effective doses. The nonhallucinogenic 5-HT_2A agonist lisuride failed to increase rearing. The results of these experiments provide strong evidence that DOM-elicited increases in rearing are due to mediation by the 5-HT_2A receptor. Finally, discriminant analysis was able to distinguish all four psychedelics from lisuride and TBG based on behavioural performance alone. Thus, increased rearing in mice could provide additional evidence of behavioural differences between hallucinogenic and nonhallucinogenic 5-HT_2A agonists.

Contrasting effects of DOI and lisuride on impulsive decision-making in delay discounting task

RATIONALE

The 5-HT2A receptor is the major target of classic hallucinogens. Both DOI (2,5-dimethoxy-4-iodoamphetamine) and lisuride act at 5-HT2A receptors, and lisuride shares comparable affinity with DOI and acts as a partial agonist at 5-HT2A receptors. However, not like DOI, lisuride lacks hallucinogenic properties. Impulsive decision-making refers to the preference for an immediate small reinforcer (SR) over a delayed large reinforcer (LR).

OBJECTIVES

The current study aims to compare the effects of DOI and lisuride on impulsive decision-making and further to investigate the possible receptor mechanisms responsible for the actions of the two drugs.

METHODS

Impulsive decision-making was evaluated in male Sprague-Dawley rats by the percentage of choice for the LR in delay discounting task (DDT). Delay to the LR changed in an ascending order (0, 4, 8, 16, and 32 s) across one session.

RESULTS

DOI (0.5 and 1.0 mg/kg) increased impulsive decision-making, and the effects of DOI (1.0 mg/kg) were blocked by the 5-HT2A receptor antagonist ketanserin (1.0 mg/kg) rather than the 5-HT2C receptor antagonist SB-242084 (1.0 mg/kg). Contrarily, lisuride (0.1, 0.3, and 0.5 mg/kg) decreased impulsive decision-making. The effects of lisuride (0.3 mg/kg) were not antagonized by ketanserin (1.0 mg/kg), selective 5-HT1A antagonist WAY-100635 (1.0 mg/kg), or selective dopamine D4 receptor antagonist L-745870 (1.0 mg/kg) but were attenuated by the selective dopamine D2/D3 receptor antagonist tiapride (40 mg/kg).

CONCLUSIONS

DOI and lisuride have contrasting effects on impulsive decision-making via distinct receptors. DOI-induced increase of impulsivity is mediated by the 5-HT2A receptor, while lisuride-induced inhibition of impulsivity is regulated by the dopamine D2/D3 receptor.

Tyrosine 7.43 is important for mu-opioid receptor downstream signaling pathways activated by fentanyl

G protein–coupled receptors can signal through both G proteins and ß-arrestin2. For the µ-opioid receptor (MOR), early experimental evidence from a single study suggested that G protein signaling mediates analgesia and sedation, whereas ß-arrestin signaling mediates respiratory depression and constipation. Then, receptor mutations were used to clarify which residues interact with ligands to selectively regulate signals in a ligand-specific manner. However, there is no systematic study on how to determine these residues and clarify the molecular mechanism of their influence on signal pathways. We have therefore used molecular docking to predict the amino acid sites that affect the binding of ligands and MOR. Then, the corresponding sites were mutated to determine the effect of the structural determinant of MOR on G_i/o protein and ß-arrestin pathways. The pharmacological and animal behavioral experiments in combination with molecular dynamics simulations were used to elucidate the molecular mechanism of key residues governing the signaling. Without affecting ligand binding to MOR, MOR^Y7.43A attenuated the activation of both G_i/o protein and ß-arrestin signaling pathways stimulated by fentanyl, whereas it did not change these two pathways stimulated by morphine. Likewise, the activation peak time of extracellular regulated protein kinases was significantly prolonged at MOR^Y7.43A compared with that at MOR^wildtype stimulated by fentanyl, but there was no difference stimulated by morphine. In addition, MOR^Y7.43A significantly enhanced analgesia by fentanyl but not by morphine in the mice behavioral experiment. Furthermore, the molecular dynamics simulations showed that H6 moves toward the cellular membrane. H6 of the fentanyl–Y7.43A system moved outward more than that in the morphine–Y7.43A system. Y7.43 mutation disrupted hydrophobic interactions between W6.48 and Y7.43 in the fentanyl–Y7.43A system but not in the morphine–Y7.43A system. Our results have disclosed novel mechanisms of Y7.43 mutation affecting MOR signaling pathways. Y7.43 mutation reduced the activation of the G_i/o protein pathway and blocked the ß-arrestin2 recruitment, increased the H6 outward movement of MOR, and disrupted hydrophobic interactions. This may be responsible for the enhanced fentanyl analgesia. These findings are conducive to designing new drugs from the perspective of ligand and receptor binding, and Y7.43 is also expected to be a key site to structure optimization of synthesized compounds.

Role of 5-HT2A receptor in modulating glutamatergic activity in the ventrolateral orbital cortex: implication in trigeminal neuralgia

5-HT_2A receptors (5-HT_2ARs) are widely expressed in the central nervous system, including in the ventrolateral orbital cortex (VLO). The VLO is an important cortical component for pain processing. Brain 5-HT_2ARs are implicated in both pro- and anti- nociceptive functions. However, the roles of 5-HT_2ARs in the VLO in trigeminal neuralgia and neuronal synaptic function remain to be understood. We used chronic constriction injury of infraorbital nerve (IoN-CCI) model and shRNA mediated gene knockdown in mice to investigate the role of 5-HT_2ARs in the VLO in trigeminal neuralgia. We found that knockdown of 5-HT_2ARs in the VLO aggravated spontaneous pain and mechanical allodynia in mice after IoN-CCI. At the synaptic level, decreasing 5-HT_2AR expression by shRNA or inhibition of 5-HT_2AR activity by its antagonist ketanserin decreased the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs) of the neurons in the VLO, whereas 5-HT_2AR partial agonist 2,5-Dimethoxy-4-iodoamphetamine (DOI) enhanced sEPSCs of the neurons in the VLO. In summary, 5-HT_2ARs in the VLO modulate the trigeminal pain by regulating neuronal glutamatergic activity.

Unveiling the Enhancement of Spontaneous Emission at Exceptional Points

Exceptional points (EPs), singularities of non-Hermitian physics where complex spectral resonances degenerate, are one of the most exotic features of nonequilibrium open systems with unique properties. For instance, the emission rate of quantum emitters placed near resonators with EPs is enhanced (compared to the free-space emission rate) by a factor that scales quadratically with the resonance quality factor. Here, we verify the theory of spontaneous emission at EPs by measuring photoluminescence from photonic-crystal slabs that are embedded with a high-quantum-yield active material. While our experimental results verify the theoretically predicted enhancement, they also highlight the practical limitations on the enhancement due to material loss. Our designed structures can be used in applications that require enhanced and controlled emission, such as quantum sensing and imaging.

AB0933 Development and Validation of a Nomogram for Prediction of Nonalcoholic Fatty Liver Disease in Psoriatic arthritis

Background

Psoriatic arthritis (PsA) has been linked to an increased risk of metabolic syndrome (MetS). Non-alcoholic fatty liver disease (NAFLD), the hepatic manifestation of MetS, is now the commonest liver disease worldwide. About 65% of PsA patients suffer from NAFLD, and chronic systemic inflammation may be an important predisposing factor.

Objectives

The purpose of this study was to establish and validate a diagnostic model nomogram for predicting the occurrence of NAFLD in patients with PsA.

Methods

A total of 127 PsA patients (46 had NAFLD and 81 had no NAFLD) were enrolled in this study. Retrospectively collected clinical and serological parameters of these patients. The percentage and absolute number of lymphocytes and CD4+T cells were determined by Flow cytometry. The independent risk factors for NAFLD were screened in the PsA patients using univariate and multivariate binary logistic regression analyses and were used for construction of the nomogram prediction model. The AUROC (C index) was used to verify the model discrimination; the calibration curve and Hosmer-Lemeshow test were used to verify the model calibration; and the DCA curve was used to verify the clinical validity of the model.

Results

Univariate and multivariate logistic regression analyses showed that Body Mass Index (BMI) (OR=1.25, P=0.001), serum triglyceride (TG) (OR=3.51，P=0.015) and peripheral blood Th1 cell percentage (OR=1.12, P < 0.001) is an independent risk factor for NAFLD in PsA patients, and an individualized nomogram prediction model was successfully established. The prediction model had a good discrimination power with AUROC (C-index) of 0.83 (95% CI: 0.76-0.90); the P value in the Hosmer-Lemeshow test was 0.683, suggesting a high reliability of the predicted probability by the model; the DCA curve indicating a good clinical efficiency of the model.

Conclusion

Our study shows that the establishment of a nomogram prediction model of PsA complicated with NAFLD patients is helpful for early clinical screening and identification of such high-risk patients.

Figure 1.

A. Example of prediction nomogram for risk of PsA complicated with NAFLD patients; B. The ROC curve of the prediction model; C. The calibration curve of the prediction model; D. The decision curve analysis of the prediction model.

Disclosure of Interests

None declared

AB0506 PRELIMINARY STUDY ON IMBALANCE BETWEEN Th17 AND REGULATORY T CELLS IN ANTIPHOSPHOLIPID SYNDROME

Background

Antiphospholipid syndrome (APS) is a typical autoimmune disease, which can be classified into primary antiphospholipid syndrome (PAPS) and secondary antiphospholipid syndrome (SAPS) based on the presence or not of other autoimmune diseases. Disorders of peripheral blood lymphocyte and CD4+T cell subsets, especially Th17 and Treg cell subsets, may be involved in the pathogenesis of APS.

Objectives

To investigate the differences of peripheral blood lymphocyte and CD4+T cell subsets between patients with primary and secondary antiphospholipid syndrome and healthy controls, and to evaluate the correlation of antiphospholipid antibody titers and Th17/Treg values in PAPS and SAPS groups, as well as the correlation of cytokines and clinical characteristics in APS patients.

Methods

A total of 67 APS patients (12 PAPS patients, 55 SAPS patients) and 40 healthy controls were enrolled in this study. Retrospectively collected clinical and laboratory data of these patients. The absolute numbers of peripheral blood lymphocyte subsets and CD4+ T cell subsets were detected by flow cytometry, and serum cytokine levels were detected by flow cytometry bead array.

Results

Compared with healthy control group, the absolute values of T [689.26 vs. 1239.00, p＜0.001], B (104.69 vs. 177.50, p＜0.001), NK (98.97 vs. 300.00, p＜0.001) and CD4+T (330.16 vs. 628.50, p＜0.001) cells in SAPS group were decreased. While only the NK cells (151.30 vs. 300.00, p＝0.002) in the PAPS group were lower than that in healthy control group. However, the absolute values of T (1295.41 vs. 689.26, p＝0.001), B (184.44 vs. 104.69, p＝0.012), NK (151.30 vs. 98.97, p＝0.023) and CD4+T cells (698.34 vs. 330.16, p＝0.002) in PAPS group were significantly higher than those in SAPS group. For CD4+T cell subsets, PAPS patients and SAPS patients showed the same trend compared with healthy controls, showing increased Th1(111.50 vs. 23.47, p=0.002 and 71.43 vs. 23.47, p=0.001, respectively), decreased Th2(6.97vs.12.43, p=0.037 and 2.49 vs. 12.43, p＜0.001, respectively) and, more importantly, decreased Treg (18.77 vs. 29.53, p=0.031 and 12.01 vs. 29.53, p＜0.001, respectively), with increased Th17/Treg ratio (0.39 vs. 0.17, p=0.001 and 0.42 vs. 0.17, p＜0.001, respectively). Meanwhile, Th2(6.97 vs. 2.46, p＝0.006), Th17 (8.42 vs. 4.00, p＝0.042) and Treg (18.77 vs. 12.01, p＝0.020) cells in PAPS group were higher than those in SAPS group. As for the correlation study, we concluded that both aCL (r=0.6061, p=0.0405) and aβ2GPI (r=0.6900, p=0.0158) were positively correlated to Th17/Treg ratio in PAPS group. In addition, for APS patients, IL-2 (r=-0.420, p=0.010), IL-4 (r=-0.392, p=0.016), IL-10 (r=-0.331, p=-0.046), IL-17 (r=-0.479, p=0.006), and IFN-γ (r=-0.339, p=0.040) were negatively correlated with titers of aCL. And IL-6 is also associated with ESR (r=0.469, p=0.004) and CRP (r=0.670, p＜0.001).

Conclusion

Whether PAPS or SAPS patients, detection and balancing of lymphocyte and CD4+T subsets, especially Th17 and Treg subsets, may help correct immune disorders. Of course, the immune function of primary and secondary APS patients is not completely consistent, at least in terms of immune cells. Also, the role of cytokines in the pathogenesis of APS should not be ignored.

Figure 1.

Comparison of lymphocyte absolute values and CD4+ T cell subsets in PAPS group, SAPS group and healthy control group.

Figure 2.

The correlation analysis between the value of Th17/Treg and the titer of aCL and aβ2GPI in PAPS group and SAPS group, respectively.

Figure 3.

Heatmap of correlation of the serum cytokine levels of a variety of cytokines with clinical and laboratory characteristics of APS patients.

Disclosure of Interests

None declared

AB0017 T HELPER /REGULATORY T CELLS RATIOS IMBALANCE IN DIFFERENT STAGING RHEUMATOID ARTHRITIS

Background

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that results in the destruction of the bone and cartilage of the joints[1].The imbalance between Th17 and Treg cells has been demonstrated to play a role in RA pathogenesis[2].With the advances in the RA field, curing and even preventing RA has become a new direction of efforts. To explore the immune characteristics in multi-staging RA is helpful for the development of accurate strategies.

Objectives

To observe the immune characteristics in different staging rheumatoid arthritis patients

Methods

A total of 127 patients with RA were recruited for this study, in cluding 30 early RA(newly diagnosed and treatment-naive,duration of disease ≤3months), 30 midddle RA (newly diagnosed and treatment-naive, duration of disease >3months and≤1 year), 30 advanced RA(newly diagnosed and treatment-naive,duration of disease >1 year) and 37 active treated RA (remissioned after target treatment and this time due to disease recurrence in hospital). All patients were hospitalized in the second hospital of Shanxi medical university and diagnosed with RA fulfilled the ACR 1987 or 2010 criteria.The percentage and absolute numbers of lymphocyte phenotypes and CD4+ T subsets in peripheral blood were examined by flow cytometry.

Results

There were no significant difference in the percentage and value of T,B,NK,CD4+T,CD8+T andCD4+T subsets. But the Th1/Th2 cell ratios in active treated RA group were increased than that in early RA, middle RA and advanced RA group.The Th17/Treg cell ratios in middle RA and advanced RA group were higher when compared with those of active treated RA group.In addition, the Th1/ Treg cell ratios were decreased in middle and advanced RA group as compared with those in active treated RA.

Conclusion

Th1/Th2,Th17/Treg and Th1/Treg imbalance varied with disease staging.The different disease staging in RA, the immune function is different. Providing targeted immunotherapy according to disease staging is helpful to improve remission rates and even prevent disease.

References

[1]Petrovská N, Prajzlerová K, Vencovský J, Šenolt L, Filková M.The pre-clinical phase of rheumatoid arthritis: From risk factors to prevention of arthritis.Autoimmun Rev.2021, 20(5):102797.

[2]Alison M Gizinski, David A Fox.T cell subsets and their role in the pathogenesis of rheumatic disease.Curr Opin Rheumatol,2014;26(2):204-10.

Figure 1.

The comparsion about the lymphocyte subsets and cell ratios in peripheral blood of different stage RA patients.(*p<0.05)

Disclosure of Interests

None declared

AB1073 HIGH INCIDENCE OF VIRUSES INFECTION IN CONNECTIVE TISSUE DISEASES PATIENTS

Background

Connective tissue diseases (CTDs) are a group of diseases with a variety of clinical manifestations. The main drug was glucocorticoids and immunosuppressive drugs, but the results are not satisfactory and the side effects are obvious, increased the incidence of infection, especially opportunistic infections. Infections becomes important causes of morbidity and mortality in CTD patients.

Objectives

To evaluate the incidence of infection in CTD patients who were clinically considered for co-infection by a combination of metagenomic next-generation sequencing (mNGS) and conventional diagnostic testing methods.

Methods

We analyzed 126 connective tissue diseases (CTD)patients with suspected infections admitted to The Second Hospital of Shanxi Medical University. All patients with CTD were diagnosed according to relevant diagnostic criteria, including 34 systemic lupus erythematosus (SLE), 24 dermatomyositis and polymyositis (DM/PM), 19 rheumatoid arthritis (RA), 10 undifferentiated connective tissue disease(UCTD),16 Sjogren syndrome (SS), 5 mixed connective tissue disease (MCTD), 5 ANCA associated systemtc vasculitis (AAV), 5 adult onset Stillystemtc isease disease(tic criteria, including 34nfections admitted to The Second Hospital of Shanxi (TA), 1 systemic sclerosis (SSC), 1retroperitoneal fibrosis (RPF). All enrolled patients were tested for conventional diagnostic testing methods(CDT) and mNGS.

Results

Among the 126 patients with CTD who were clinically considered for co-infection, 31 patients were negative for mNGS, and pathogens were detected in 99 of them. In our results, the mNGS and CDT were both positive for pathogens detection in 28 individuals.Of both positive individuals, 2 cases were perfect matches,12 cases were partly matched, 14 cases were totally mismatched. A total of 23 cases were negative for both mNGS and CDT. 70 cases were positive for mNGS only.There were only 5 cases positive for pathogens detection by CDT only. In addition, the results of mNGS showed that 131 patients were virus-positive(54%), 78 patients were prokaryotes-positive (37%) inculding bacteria, mycoplasma and 14 patients were eukaryotes-positive (9%). Of course, someones have mixed infections among these patinets some of these patients, with two or more pathogens. In the mixed infection, 5 cases have no viruses infection, 38 cases with virus infection, including 20 cases of bacteria and viruses infection, 4 cases of bacteria,fungi and viruses infection, 9 cases of viruses mixed infection, 1 case of bacteria,viruses,fungi and mycoplasma infection, 1 case of bacteria,viruses and mycoplasma infection, 1 case of viruses and mycoplasma infection, 1 case of viruses and fungi infection. According to the results, viruses were the most common pathogens identified, followed by prokaryotes and eukaryotes. It is noteworthy that the incidence of Human gammaherpesvirus 4(EBV), Human betaherpesvirus 5(CMV) and Human alphaherpesvirus 1 are more common in virus-positive. The most frequently detected prokaryotes were Acinetobacter baumannii, Mycobacterium tuberculosis complex, followed by Staphylococcus aureus, Prevotella melaninogenica,Staphylococcus homini and Helicobacter pylori. The major pathogens were Pneumocystis jirovecii and Candida albicans among eukaryotes-positive individuals.

Conclusion

As a complementary approach to conventional methods, mNGS could help improving the identification of infection in CTD patients.The incidence of viral infection is high in patients with connective tissue disease and close attention should be paid to it in clinical works.

Figure 1.

A. Comparison of test results between mNGS and conventional diagnostic testing methods(CDT) in CTD patients. B. The classification of mixed infections with or without viruses infection detected by mNGS and conventional diagnostic testing methods(CDT).

Figure 2.

Distribution of pathogens detected by mNGS. A. Type distribution of pathogens identified by mNGS. Species distribution of viruses of B.viruses, C.Prokayote, D. Eucayon detected by mNGS.

Disclosure of Interests

None declared

POS0549 IMBALANCED Tfr/Tfh IN PERIPHERAL BLOOD OF NEW-ONSET RHEUMATOID ARTHRITIS

Background

Rheumatoid arthritis (RA) is a kind of autoimmune disease characterized with chronic aggressive arthritis, presence of abnormal antibodies and persistent synovitis[1]. However, the pathogenesis of RA remained unclear by now. Several observations have showed that the breakdown of immune tolerance was involved in the development of RA. T follicular regulatory (Tfr) cells and T follicular helper (Tfh) cells, as a new subset of CD4+T cell, can exert an opposite effect in the regulation of humoral immunity[2]. Intensive researches have showed that the imbalance of Tfr/Tfh cell is related to the pathogenesis and development of autoimmune disease. There is still a lack of understanding of the relationship between Tfr/Tfh and RA, which needs further exploration.

Objectives

To detect the expression of Tfh and Tfr cells in thr peripheral blood of patients with new-onset RA and healthy controls, and to explore the role of Tfh and Tfr cells in the pathogenesis and development of RA.

Methods

We enrolled 26 patients with new-onset RA who hospitalized at the Second Hospital of Shanxi Medical University from the June 2021 to the November 2021. And 17 age and gender-matched healthy adults were anticipated as controls. The absolute number of Tfh and Tfr cells in peripheral blood was detected by flow cytometry. Disease activity indicators were collected including erythrocyte sedimentation rate (ESR, mm/h) and Disease Activity Score in 28 joints (DAS28). Then we compared the expression of Tfh and Tfr cells between the patients and healthy controls and conducted the correlation analysis with disease activity.

Results

There was significant decreased level of Tfr cells in the patients with new-onset RA compared with healthy controls (P<0.001) and a lower ratio of Tfr/Tfh in the patients (P<0.01). The reduced Tfr cells and Tfr/Tfh were significant negative correlation with the disease activity indicators including ESR and DAS28 (r=-0.305, P=0.033). There was no statistically significant in the absolute number of Tfh cells between patients and healthy controls, but the level of Tfh cell showed an increasing trend in new-onset RA.

Conclusion

The results we investigated here showed that new-onset RA exhibited an imbalance of Tfr/Tfh, specifically reduced Tfr cells, compared with healthy controls, which were negatively correlated with higher disease activity in RA. It was likely that the imbalance of Tfr/Tfh in peripheral blood played an important role in the development of RA, which may be a target to treat RA.

Table 1.

A summary of data of all enrolled patients with RA and healthy controls

HC(n=17)New-onset RA(n=26)P valueAge(years)51.94±13.0355.88±13.56P=0.35Sex(male/female)4/137/19P=0.81ESR(mm/h) a-54.85±32.71-DAS28 a-5.09±1.56-Tfh cell count(cell/UL)b43.156(23.277,106.638)83.914(38.133,119.662)0.214Tfr cell count(cell/UL)b1.422(0.882,1.893)0.441(0.116,2.888)0.025*Tfr/Tfhb0.030(0.014,0.049)0.011(0.001,0.024)0.001**

a Results are expressed as the mean ± standard error. b Results are expressed as the median(Q1,Q3).

Normally distributed continuous variables were analyzed by the independent-samples Student’s t-test. And nonparametric variables were analyzed by Mann–Whitney U test

Figure 1.

The differences of Tfr and Tfh cells in peripheral blood between the healthy controls and patients with RA. Tfr cells were higher in new-onset RA leading to an imbalance of Tfr/Tfh. Statistical analyses were performed by the Mann-Whitney U test. (*P<0.05, **P<0.01)

Figure 2.

The correlation of disease activity with the level of Tfr cells and Tfr/Tfh. Tfr cells and Tfr/Tfh were negative associated with ESR and DAS28. Statistical analyses were performed by the Spearman correlation analysis.

References

[1]Sparks, J.A. Rheumatoid Arthritis [J]. Ann Intern Med, 2019, 170(1).DOI: 10.7326/AITC201901010.

[2]Deng, J., Y. Wei, V.R. Fonseca, L. Graca, and D. Yu. T follicular helper cells and T follicular regulatory cells in rheumatic diseases [J]. Nat Rev Rheumatol, 2019, 15(8): 475-490.DOI: 10.1038/s41584-019-0254-2.

Disclosure of Interests

None declared.

Gs signaling pathway distinguishes hallucinogenic and nonhallucinogenic 5-HT2AR agonists induced head twitch response in mice

5- HT2A receptor is a member of the family A G-protein-coupled receptor. It is involved in many psychiatric disorders, such as depression, addiction and Parkinson's disease. 5-HT2AR targeted drugs play an important role in regulating cognition, memory, emotion and other physiological function by coupling G proteins, and their most notable function is stimulating the serotonergic hallucination. However, not all 5-HT2AR agonists exhibit hallucinogenic activity, such as lisuride. Molecular mechanisms of these different effects are not well illustrated. This study suggested that 5-HT2AR coupled both Gs and Gq protein under hallucinogenic agonists DOM and 25CN-NBOH stimulation, but nonhallucinogenic agonist lisuride and TBG only activates Gq signaling. Moreover, in head twitch response (HTR) model, we found that cAMP analogs 8-Bromo-cAMP and PDE4 inhibitor Rolipram could increase HTR, while Gs protein inhibitor Melittin could reduce HTR. Collectively, these results revealed that Gs signaling is a key signaling pathway that may distinguish hallucinogenic agonists and nonhallucinogenic agonists.

Genome-wide association study of fleece traits in Inner Mongolia Cashmere goats

Inner Mongolia Cashmere goat is a well-known local cashmere goat breed in China. It is famous for excellent fleece quality and a significant advantage in cashmere yield compared to other cashmere goat breeds. In this study, a genome-wide association study was used to investigate fiber length, fiber diameter, and cashmere yield of 192 Inner Mongolia Cashmere goats using the Illumina GoatSNP52K Beadchip panel. We discovered that four single nucleotide polymorphisms (SNPs) reached genome-wide significance levels. These SNPs were located in some genes, e.g. FGF12, SEMA3D, EVPL, and SOX5, possibly related to fleece traits in Inner Mongolia Cashmere goat. Gene ontology enrichment analysis revealed that these genes were enriched in several biological pathways that were involved in hair follicle development in cashmere goats. In summary, the identified significant SNPs and genes provide useful information to explore genetic mechanisms underlying the variation in fleece traits and genomic selection of Chinese cashmere goat.

AB0017 IMMUNE CHARACTERISTICS OF PERIPHERAL BLOOD IN SECONDARY SJOGREN’S SYNDROME PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Secondary Sjogren’s Syndrome (sSS) is diagnosed when symptoms of SS coexist with other systemic connective tissue disease, often secondary to rheumatoid arthritis(RA).The occurrence of SS secondary with RA will worsen the course of disease and increase the high incidence and mortality of RA. At present, the immune characteristics of peripheral blood of sSS with RA are not clear.

Objectives:

To observe the difference of immune Immune characteristics in peripheral blood between sSS secondary to RA, primary Sjogren’s syndrome(pSS) and RA patients.

Methods:

20 sSS with RA patients, 20 pSS paients and 20 RA pateints hospitalized in ShanXi medical university the second Hospital were enrolled. The percentage and absolute numbers of lymphocyte phenotypes and CD4+ T subsets in peripheral blood were examined by flow cytometry.

Results:

As for the percentage and absolute number of total T, B, NK, CD4+T,CD8+ T and the ratio of CD4 + T to CD8+ T cells, there was no significant difference between the sSS with RA, RA, and SS group. There was also no statistical difference in the percentage of CD4+T subsets(Th1,Th2,Th17 and Treg) between the three groups. But the ratio of Th17 and Treg in sSS with RA group was increased than pSS group.About comparison of absolute number of CD4+T subsets, there was no statistical difference among the three groups except that the Th1 cells in RA group was significantly higher than SS group.

Conclusion:

Elevated Th17/Treg may be an immunological feature that differentiates sSS with RA patients from pSS patients. In addition, in general, peripheral blood of patients with RA and SS have similar immune characteristics.

References:

[1]Wei W,Ahmad S S, Chi S. From Molecular Mechanism to the Etiology of Sjogren Syndrome.Curr Pharm Des. 2018;24(35):4177-4185.

[2]Hajiabbasi A, Masooleh I S,Alizadeh Y, Secondary Sjogren’s Syndrome in 83 Patients With Rheumatoid Arthritis.Acta Med Iran.2016;54(7):448-53.

Figure 1.

The comparsion about the lymphocyte phenotypes and CD4+ T subsets in peripheral blood of sSS with RA(n=20), pSS(n=20) and RA patients(n=20).(*p<0.05,**p<0.001,*p<0.0001)

Disclosure of Interests:

None declared

POS1006 ABERRANT Th17 CELLS EXPANSION AND RISK FACTORS IN ANKYLOSING SPONDYLITIS PATIENTS COMPLICATED WITH CARDIOVASCULAR EVENTS

Background:

The incidence of Ankylosing Spondylitis (AS) complicated with cardiovascular diseases (CVD) has increased in recent years [1]. However, identification of risk factors indicating the development of CAD in AS patients is lacking. Th17 cells are increasingly recognized to be important in atherogenesis [2]. However, the role of these cells in the pathogenesis of ankylosing spondylitis patients complicated with cardiovascular events remains elusive.

Objectives:

This study aimed to assess the level of circulating Th17 cells as well as other lymphocyte subsets such as Treg, Th, Ts, and NK cells in AS combined with CVD, and further to evaluate whether elevations in special PBMC subpopulations in AS patients indicate an increased risk of CVD.

Methods:

Samples were assessed from 141 AS patients hospitalized at the Second Hospital of Shanxi Medical University (60 AS patients combined with CVD and 81 AS patients without CVD) and 100 healthy controls. The absolute numbers of lymphocytes and CD4+ T cells in peripheral blood were determined using Flow Cytometer. The association between PBMC subpopulations and CVD development in AS patients were analyzed using multivariable logistic regression.

Results:

1. Compared with AS group, AS with CVD group exhibited significant increases in the number of Th17 cells (P=0.001) and Treg cells (P=0.046). The ratio of Th17/Treg was also increased (P=0.085).

2. Analogous increases in the absolute number (P<0.001) and frequency (P<0.001) of Th1 cells, as well as the ratio of Th1/Th2 (P<0.001) and Th1/Treg (P=0.004) were also present in AS with CVD patients, compared to those without CVD.

3. Compared to HCs, 141 AS patients showed significantly decreased Treg cells (P<0.012) and increased Th17/Treg (P=0.001).

4. Logistic regression showed age (odds ratio: 1.09; 95% CI: 1.035-1.137), hypertension (odds ratio: 3.31; 95% CI: 1.152-9.528), diabetes (odds ratio: 8.03; 95% CI: 1.251-51.503), and elevated level of Th1 number (odds ratio: 1.01; 95% CI: 1.003-1.016) and DD (D-dimer) (odds ratio: 1.00; 95% CI: 1.000-1.002) were significantly correlated with the onset of CVD in AS patients.

5. Smoke, increased Th17 level, and use of NSAIDS were also positively correlated with the onset of CVD although the P-values did not reach significant.

Conclusion:

Our data indicates aberrant expansion of Th17 cells in AS with CVD patients. Moreover, age, hypertension, diabetes, and increased level of Th1 in PBMC and DD are single independent risk factors for the presence of CVD in AS. The mechanisms of atherogenesis in AS may associate with the elevations in Th1 and Th17 cells. Imbalance of Th1/Th2 and Th17/Treg may be shared etiologic pathways of AS and CVD, providing attractive targets for the prevention and therapy of CVD development in AS patients.

References:

[1]Kim JH, Choi IA. Cardiovascular morbidity and mortality in patients with spondyloarthritis: A meta-analysis. Int J Rheum Dis (2020). doi: 10.1111/1756-185x.13970.

[2]Saigusa R, Winkels H, Ley K. T cell subsets and functions in atherosclerosis. Nat Rev Cardiol. 2020 Jul;17(7):387-401. doi: 10.1038/s41569-020-0352-5.

Figure 1.

Compared with AS group, AS with CVD group exhibited significant increases in the number of Th17 cells (P=0.001) and Treg cells (P=0.046). The ratio of Th17/Treg was also increased (P=0.085). The absolute number (P<0.001) and frequency (P<0.001) of Th1 cells, as well as the ratio of Th1/Th2 (P<0.001) and Th1/Treg (P=0.004) were also present in AS with CVD patients.

Disclosure of Interests:

None declared.

AB0762 THE CHARACTERISTICS OF PERIPHERAL LYMPHOCYTE SUBSETS IN PATIENTS WITH IGG4-RELATED DISEASE

Background:

Immunoglobulin G4-related disease (IgG4-RD) is an autoimmune disease with chronic systemic inflammation and fibrosis. The main feature of the disease was diffuse swell of the affected organs, and the serum IgG4 level was increased. Histopathology of the lesions showed infiltration of IgG4+ plasma cells. However, the pathogenesis of IgG4-RD is still unclear[1].

Objectives:

To explore the clinical characteristic of lymphocyte subsets of IgG4-related disease patients, and make comparisons with healthy controls.

Methods:

A total of 31 patients with IgG4-RD who were admitted to the Rheumatic Immunology Department of the Second Hospital of Shanxi Medical University from January 2016 to June 2020 were included. We collected their Clinical and laboratory data, and selected 30 age and sex matched healthy people as the control group. Flow cytometry was used to detect the percentage and absolute number of lymphocyte subsets (T, B, NK, CD4+T, CD8+T) and CD4+T subsets (Th1, Th2, Th17, CD4+CD25+Foxp3+Treg) in peripheral blood of IgG4-RD patients and healthy controls.

Results:

(1)The percentage of CD4+T cells in peripheral blood of IgG4-RD patients was higher than that of healthy controls [45.00(33.97-51.48) vs. 39.36(33.78-43.30), P<0.05]. (2)The percentage and absolute number of Th17 cells was increased in IgG4-RD patients [1.13(0.70-1.55) vs. 0.77(0.43-1.07), P<0.05; 7.90(5.20-12.23) vs. 5.60(3.12-8.47), P<0.05], while the percentage of Treg cells was decreased [3.37(2.82-5.65) vs. 4.96(4.18-6.34), P<0.01]. But Treg cells number showed no difference between the two groups. (3) Th17/Treg ratio was significantly increased in IgG4-RD patients [0.29(0.16-0.46) vs. 0.15(0.08-0.23), P<0.01], and it was positively correlated with IgG4-RD response index score(r=0.491, P<0.01). (Table 1).

Table 1.

Comparation of absolute number and percentage of peripheral blood lymphocyte subsets between IgG4-RD patients(n=31) and healthy controls (n=30).

cell subsetsIgG4-RD (n=31)HC(n=30)P valueB150.59(120.14-212.38)203.27(152.90-244.27)0.089B%8.74(6.46-11.45)10.03(8.26-13.21)0.059NK261.98(178.82-303.08)290.83(179.93-451.45)0.175NK%13.14(9.92-18.10)16.50(11.24-21.75)0.105CD3+T1357.44(992.00-1844.82)1305.81(978.24-1597.94)0.708 CD3+T%72.62(69.32-76.96)71.62(64.97-75.25)0.135CD8+T436.40(342.71-596.86)513.50(359.73-620.53)0.665CD8+T%24.26(19.48-31.27)26.50(20.67-32.90)0.535CD4+T741.00(562.78-1095.52)664.50(585.52-789.97)0.428CD4+T%45.00(33.97-51.48)39.36(33.78-43.30)0.032Th1162.32(108.11-216.61)144.27(81.52-161.66)0.094Th1%19.00(15.24-25.54)18.46(14.86-24.27)0.644Th27.82(5.35-11.78)8.25(5.32-10.87)0.817Th2%1.00(0.76-1.27)1.24(0.89-1.64)0.399Th177.90(5.20-12.23)5.60(3.12-8.47)0.010Th17%1.13(0.70-1.55)0.77(0.43-1.07)0.026Treg24.45(19.76-44.79)34.55(27.29-46.57)0.076Treg%3.37(2.82-5.65)4.96(4.18-6.34)0.003Th1/Th220.00(13.78-36.36)14.97(10.31-21.58)0.135Th1/Treg5.72(2.92-8.86)3.68(2.53-4.77)0.021Th2/Treg0.27(0.16-0.52)0.22(0.15-0.32)0.199Th17/Treg0.29(0.16-0.46)0.15(0.08-0.23)0.002

Conclusion:

Th17/Treg immune disorder exists in IgG4-RD patients, and it is related to the disease activity, indicating that Th17/Treg imbalance may be an important pathogenesis of IgG4-RD.

References:

[1]Kamisawa T, Zen Y, Pillai S, et al. IgG4-related disease[J]. Lancet, 2015, 385(9976): 1460-1471.

Disclosure of Interests:

None declared

A20-Binding Inhibitor of Nuclear Factor-κB Targets β-Arrestin2 to Attenuate Opioid Tolerance

Opioids play an important role in pain relief, but repeated exposure results in tolerance and dependence. To make opioids more effective and useful, research in the field has focused on reducing the tolerance and dependence for chronic pain relief. Here, we showed the effect of A20-binding inhibitor of nuclear factor-κB (ABIN-1) in modulating morphine function. We used hot-plate tests and conditioned place preference (CPP) tests to show that overexpression of ABIN-1 in the mouse brain attenuated morphine dependence. These effects of ABIN-1 are most likely mediated through the formation of ABIN-1-β-arrestin2 complexes, which accelerate β-arrestin2 degradation by ubiquitination. With the degradation of β-arrestin2, ABIN-1 overexpression also decreased μ opioid receptor (MOR) phosphorylation and internalization after opioid treatment, affecting the β-arrestin2-dependent signaling pathway to regulate morphine tolerance. Importantly, the effect of ABIN-1 on morphine tolerance was abolished in β-arrestin2-knockout mice. Taken together, these results suggest that the interaction between ABIN-1 and β-arrestin2 inhibits MOR internalization to attenuate morphine tolerance, revealing a novel mechanism for MOR regulation. Hence, ABIN-1 may be a therapeutic target to regulate MOR internalization, thus providing a foundation for a novel treatment strategy for alleviating morphine tolerance and dependence. SIGNIFICANCE STATEMENT: A20-binding inhibitor of nuclear factor-κB (ABIN-1) overexpression in the mouse brain attenuated morphine tolerance and dependence. The likely mechanism for this finding is that ABIN-1-β-arrestin2 complex formation facilitated β-arrestin2 degradation by ubiquitination. ABIN-1 targeted β-arrestin2 to regulate morphine tolerance. Therefore, the enhancement of ABIN-1 is an important strategy to prevent morphine tolerance and dependence.

A large dose of methamphetamine inhibits drug‑evoked synaptic plasticity via ER stress in the hippocampus

Drug addiction is a chronic and recurrent disease associated with learning and memory. Shaped by drug use and cues from the environment, drug memory serves a key role in drug‑seeking behaviour. Methamphetamine (MA), a globally abused drug, causes cognitive impairment, and endoplasmic reticulum (ER) stress is one of the mechanisms via which this occurs. In the current study, it was hypothesized that ER stress may serve a role in the disturbance of drug memory. The present study demonstrated that 5 mg/kg MA inhibited conditioned place preference behaviour via ER stress, which caused a disruption in long‑term potentiation in the hippocampus. When mice were pre‑treated with the ER stress inhibitors 4‑phenyl butyric acid or tauroursodeoxycholic acid, drug‑evoked synaptic plasticity was induced. Western blotting results indicated that treatment with 5 mg/kg MA enhanced the expression of cyclin‑dependent kinase‑5 and decreased the expression of Ca2+/calmodulin‑dependent protein kinase II α via ER stress. Collectively, the present results suggested that a large dose of MA inhibited drug‑evoked synaptic plasticity and disrupted drug memory by inducing ER stress.

Methamphetamine Inhibits Long-Term Memory Acquisition and Synaptic Plasticity by Evoking Endoplasmic Reticulum Stress

Methamphetamine (MA), an illicit drug abused worldwide, leads to cognitive impairment and memory loss. However, the detailed mechanisms of MA-induced neurologic impairment are still unclear. The present study aimed to investigate the mechanisms of MA-induced inhibition of memory acquisition from the perspective of endoplasmic reticulum (ER) stress. ER stress, caused by the accumulation of wrongly folded proteins in the ER, is important for new protein synthesis, which further influence the formation of long-term memory. A subacute MA poisoning model of mice was established and several behavioral experiments were performed, including elevated plus maze, Morris water maze, electro-stimulus Y-maze, and novel object recognition tasks. The present results suggested that 4 days exposure to MA induced significant memory loss. Whereas, this damage to memory formation could be protected when mice were pre-treated with ER stress inhibitor, tauroursodeoxycholic acid (TUDCA). The results of Western blotting showed that subacute exposure to MA increased the expression levels of ER stress marker proteins, such as binding immunoglobulin protein, phosphorylated eukaryotic translation initiation factor 2α, cyclic AMP-dependent transcription factor (ATF)-4, ATF-6, and CCAAT-enhancer binding protein homologous protein. Meanwhile, the enhanced expression levels of these proteins were reversed by TUDCA, indicating that MA administration induced memory loss by evoking ER stress in the hippocampus. We also found that MA inhibited the induction of long-term potentiation (LTP) in the hippocampus. Nevertheless, LTP could be induced when mice were pre-treated with TUDCA. In conclusion, MA inhibited long-term memory acquisition and synaptic plasticity via ER stress.

Design of super-strong and thermally stable nanotwinned Al alloys via solute synergy

Al alloys have widespread industrial applications. However, their mechanical strength is often much lower than steels. Here, we investigate the influence of solutes on achieving ultrahigh strength and thermal stability of nanotwinned Al alloys. In situ micropillar compression tests show the addition of a small amount of Ti can significantly increase the mechanical strength of Al-Ni alloys to 2 GPa. Deformation induced detwinning, Ni segregation and grain coarsening as discovered in binary Al-Ni alloys are mostly absent in the ternary Al-Ni-Ti alloys. Moreover, the ternary Al-Ni-Ti alloys have outstanding thermal stability. Density function theory calculations reveal the synergetic pinning effect of Ni-Ti solute pairs on incoherent twin boundaries. This study demonstrates that the proper selection of synergistic solute pairs is critical to improve the thermal stability and mechanical properties of nanotwinned Al alloys.

Association between SLCO1B1 polymorphism distribution frequency and blood lipid level in Chinese adults

BACKGROUND

The variation of serum lipid levels can be part-related to certain genes. One such gene, SLCO1B1, encodes a transporter that may have a role in lipid metabolism. We hypothesised that differences in certain SLCO1B1 genotypes are related to levels of serum lipids.

MATERIALS AND METHODS

We recruited 636 subjects who were genotyped for SLCO1B1 variants *1a, *1b, *5 and *15. Routine liver function tests, renal function tests and routine lipid indices were measured by standard techniques.

RESULTS

The most frequent genotypes were *1b/*1b (29.3%), *1b/*15 (27.5%), *1a/*1b (21.1%), *1a/*15 and *1b/*5 (10.2%) and *1a/*1a (8.5%). There were significant differences in levels of triglycerides and HDL in the four SLCO1B1 genotypes *1a/*1a, *1b/*1b, *1a/*1b and *1b/*15 (all p < 0.05).

CONCLUSION

The genotypes *1a/*1a and *1a/*1b indicate a high risk of cardiovascular disease, while the *1b/*1b group may have a relatively low risk. SLCO1B1 may be involved in the metabolism of triglycerides and HDL. We have provided a tool for identifying potentially high-risk groups that could be helpful for early diagnosis and prevention, individualized drug therapy and even gene therapy.

Distribution of Acid Sensing Ion Channels in Axonal Growth Cones and Presynaptic Membrane of Cultured Hippocampal Neurons

Although acid-sensing ion channels (ASICs) are widely expressed in the central nervous system, their distribution and roles in axonal growth cones remain unclear. In this study, we examined ASIC localization and function in the axonal growth cones of cultured immature hippocampal neurons. Our immunocytochemical data showed that native and overexpressed ASIC1a and ASIC2a are both localized in growth cones of cultured young hippocampal neurons. Calcium imaging and electrophysiological assay results were utilized to validate their function. The calcium imaging test results indicated that the ASICs (primarily ASIC1a) present in growth cones mediate calcium influx despite the addition of voltage-gated Ca²⁺ channels antagonists and the depletion of intracellular calcium stores. The electrophysiological tests results suggested that a rapid decrease in extracellular pH at the growth cones of voltage-clamped neurons elicits inward currents that were blocked by bath application of the ASIC antagonist amiloride, showing that the ASICs expressed at growth cones are functional. The subsequent immuno-colocalization test results demonstrated that ASIC1a and ASIC2a are both colocalized with Neurofilament-H and Bassoon in mature hippocampal neurons. This finding demonstrated that after reaching maturity, ASIC1a and ASIC2a are both distributed in axons and the presynaptic membrane. Our data reveal the distribution of functional ASICs in growth cones of immature hippocampal neurons and the presence of ASICs in the axons and presynaptic membrane of mature hippocampal neurons, indicating a possible role for ASICs in axonal guidance, synapse formation and neurotransmitter release.

SAT0278 LOW-DOSE IL-2 RESTORES TREG-MEDIATED IMMUNE TOLERANCE IN PATIENTS WITH ANCA-ASSOCIATED VASCULITIS

Background:

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of autoimmune disease that can cause systemic organ damage, including granulomatosis with polyangiitis(GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis(EGPA)[1]. Several observations have showed that the breakdown of immune tolerance was involved in the pathogenesis of AAV [2], furthermore, a single, open and clinical trial demonstrates that IL-2 can be used to treat patients with GPA [3]. But there is still a lack of understanding of the relationship between Th17 / Treg and AAV and evidence for the therapeutic effect of IL-2 on AAV, which needs further exploration.

Objectives:

We first measured the absolute number of CD4+T subsets in peripheral blood of patients to explore the pathogenesis of AAV, and then investigated the effects of short-term and low-dose recombinant human IL-2 (rhIL-2) on CD4+T subsets of patients to analyze the regulatory effect of IL-2 on AAV.

Methods:

49 patients with AAV, hospitalized at the Second Hospital of Shanxi Medical University from the May 2016 to the November 2019 were enrolled, including 36 patients who were only received conventional glucocorticoids and DMARDs, and other 13 patients who were not only received these treatments but were also injected subcutaneously rhIL-2(50WIU/day for a 5-day course). 31 age and gender-matched healthy adults were selected as controls. The absolute number of Th17 and Treg cells in peripheral blood of health controls and the patients before and after treatment was detected by flow cytometry.

Results:

There was significant decreased level of Treg cells in the patients with AAV compared with healthy controls (P<0.001) leading to a higher Th17/Treg ratio in the patients with AAV, but there was no statistically significant in the absolute number of Th17 cells between the patients and healthy controls. After the treatment of short-term and low-dose IL-2, there was a significant increase in the absolute number of Treg cells (P<0.01) leading to a decrease in the ratio of Th17 and Treg (p<0.05).The absolute number of Th17 had a trend towards higher values but was not statistical significance.

Conclusion:

The difference of Treg cells between the patients and healthy controls suggested that the decreased number of Treg cells failed to control autoimmune inflammatory response contributing to the pathogenesis of AAV. After the treatment of short-term and low-dose rhIL-2, there was a more significant increase in the absolute number of Treg cells showing that IL-2 could selectively stimulate the growth of Treg cells and restore the Treg-mediated immune tolerance in patients with AAV to achieve disease remission.

References:

[1]Cosmi, L.,Th17 and Treg lymphocytes as cellular biomarkers of disease activity in Granulomatosis with Polyangiitis.Eur J Immunol, 2017.47(4): p. 633-636.

[2]Pagnoux, C.,Updates in ANCA-associated vasculitis.Eur J Rheumatol, 2016.3: p. 122-133.

[3]Rosenzwajg, M., et al.,Immunological and clinical effects of low-dose interleukin-2 across 11 autoimmune diseases in a single, open clinical trial.Annals of the Rheumatic Diseases, 2019.78(2): p. 209-217.

Disclosure of Interests:

None declared

AB0269 THE CHARACTERISTICS OF PERIPHERAL LYMPHOCYTE SUBSETS AND CYTOKINES LEVEL IN RHEUMATOID ARTHRITIS WITH CORONARY ARTERY DISEASE

Background:

Rheumatoid arthritis (RA) is a systemic autoimmune disease. It is characterized by highly disabling polyarthritis, but extra-articular features are also common and portend a poor prognosis. Compared with the general population, the incidence and mortality of cardiovascular disease in RA are significantly increased. Chronic autoimmune inflammation is the common pathogenesis of RA and coronary heart disease(CAD). We’ve proved that lymphocyte subsets imbalance and high cytokines expression play an important role in the occurrence and development of RA diseases. However, the level of lymphocyte subsets and cytokines of RA patients with CAD are rarely reported[1-2].

Objectives:

To explore the clinical characteristic of lymphocyte subsets and cytokines of RA patients with CAD,and make comparisons with simple RA patients and healthy controls.

Methods:

The study included 96 patients with a diagnosis of RA according to the 1987 revised criteria of the ACR, including 54 RA patients with CAD and 42 RA patients without CAD and other cardiovascular disease, 40 healthy controls are also concluded. The absolute numbers of lymphocyte subsets and T subsets in peripheral blood were measured by Flow Cytometer (FCM). Serum levels of IL-2, IL-4, IL-6, IL-10, IL-17, INF-γ, and TNF-α were measured by flow microsphere capture chip technique (CBA) for 19 RA patients with CAD and 38 simple RA patients among 96 patients.We also collected relevant clinical information and made DAS28 score, and all patients are in the middle-high disease activity group (DAS28>3.2).

Results:

(1) There was no difference in DAS28 scores between the two groups(p=0.572). (2)Compared with RA patients without CAD, the absolute number of total T cell(P=0.035), total B cell (P=0.006), CD4+T cell(P=0.012), Th1 cell(P=0.037), Th17 cell(P=0.033) and CD4+CD25+FOXP3+ Treg(P=0.003) was lower than RA patients with CAD, the number of NK cell(P=0.685), CD8+T cell(P=0.322) and Th2 cell(P=0.770) had no obvious difference between them. (3)Compared with the healthy control, the absolute number of total T cell(P=0.014), total B cell (P=0.006), CD8+T cell(P=0.000) in RA with CAD was evidently lower, but there was no siginificant difference in absolute number of CD4+T cell(P=0.582), Th1 cell(P=0.052), Th2 cell(P=0.595), Th17 cell(P=0.148) and Treg(P=0.176) (Figure 1).(4) In RA patients with CAD,the level of cytokines IL-2(P=0.042), IL-4(P=0.043) and IL-17(P=0.012) was lower, while other cytokines had no difference (Table 1).

Figure 1.

The absolute number of lymphcytes of RA patients with CAD(n=54),RA patients without CAD (n=42) and healthy control (n=40). (*P<0.05,**P<0.01, ***P<0.001).

Table 1.

The expression level of cytokines of RA patients with CAD(n=19) and RA patients without CAD (n=38).

Cytokines (pg/ml)RA and CAD group(A) (n = 19)RA group(B) (n = 38)PvalueA vs. BIL-25.50(1.96, 12.82)6.82(4.45, 14.44)0.042IL-44.93(1.67, 9.41)6.28(4.49, 11.88)0.043IL-623.69(10.93, 73.08)36.67(15.40, 72.50)0.636IL-107.76(4.54, 10.50)7.62(5.69, 19.91)0.223IL-1710.81(4.04, 20.25)20.68(13.88, 45.58)0.012IFN-γ6.10(3.27, 13.84)7.13(5.79, 15.83)0.115TNF-α10.49(2.50, 29.04)14.96(10.03, 30.39)0.097

Conclusion:

Our research shows that there is lymphocyte imbalance and immune disorder existing in RA patients with CAD. Both the number of lymphocyte subsets and cytokine levels decreased in these patients than pure RA patients. It suggests that this group may be in lower immune state, which providing guidance for further clinical treatment of RA patients with CAD.

References:

[1]Winchester R, Giles JT, Nativ S, et al. Association of Elevations of Specific T Cell and Monocyte Subpopulations in Rheumatoid Arthritis With Subclinical Coronary Artery Atherosclerosis. [J]. Arthritis Rheumatol, 2016,68(1): 92-102.

[2]England BR, Thiele GM, Anderson DR, et al. Increased cardiovascular risk in rheumatoid arthritis: mechanisms and implications. [J]. BMJ, 2018 04 23;361.

Disclosure of Interests:

None declared

AB0043 THE IMBALANCE OF T FOLLICULAR REGULATORY CELL AND T FOLLICULAR HELPER CELL IN RHEUMATOID ARTHRITIS

Background:

Rheumatoid arthritis (RA) is a chronic inflammatory disease which can lead to severe joint damage and disability.The relationship between antibodies and rheumatoid arthritis has long been well established. Recently, many studies have found that T follicular regulatory cells(Tfr) and T follicular helper cells (Tfh) are closely related to antibody generation on lymphoid follicular germinal centers (GCs)[1-2]. Tfr cells can inhibite the GC reaction and suppress production of high-affinity antibodies. The dysregulation of Tfh cells can lead to the production of autoantibodies by B cells.

Objectives:

To examine the expression of circulating T follicular regulatory cell (Tfr) and T follicular helper cell and its subsets(Tfh1 Tfh2 Tfh17) in RA patients and healthy control group.

Methods:

Level of Tfr and Tfh1,Tfh2 and Tfh17 cells in the peripheral blood of 17 new RA patients, 30 treated RA patients and 18 healthy controls were deceted by flow cytomery. All patients were hospitalised at the Department of Rheumatology, Second Hospital of Shanxi Medical University.

Results:

We found that the level of Tfr (CD3+CD4+CD25+CXCR5+FOP3+) percent(P=0.020), in the peripheral blood in RA patients were significantly decreased compared with healthy controls. The percent of Tfh (CD3+CD4+CXCR5+CD45RA-) (P=0.039)and Tfh17 (CD3+CD4+CXCR5+CD45RA-CXCR3-CCR6+) (P=0.000)were increased, but there are no statistical difference about Tfh1(CD3+CD4+CXCR5+CD45RA-CXCR3+CCR6-)(P=0.558) and Tfh2 (CD3+CD4+CXCR5+CD45RA-CXCR3-CCR6-) percent(P=0.079). We compared the above indicators between new and treated RA patients, and the results indicated that the Tfr(P=0.013),Tfh (P=0.002) and Tfh1(P=0.034) were significantly increased in the new RA patients compared to the treated RA patients, there were no differences between the two groups in Tfh2(P=0.419) and Tfh17 percent(P=0.124).

Conclusion:

Our results indicated that disorder of Tfr and Tfh subsets were involved in RA, restoring the Tfr/Tfh balance may be the potential therapeutic targets.

Fig. 1.

Comparison of Tfr, Tfh and its subsets(Tfh1 Tfh2 Tfh17) percent among the RA patients (n = 47) and healthy control group (n = 18) (*P < 0.05).

Fig. 2.

Comparison of Tfr,Tfh and its subsets(Tfh1 Tfh2 Tfh17) percent among the new RA patients (n = 17) and treated RA patients(n = 30) (*P < 0.05).

References:

[1]Deng J, Wei Y, Fonseca VR, Graca L, Yu D.T follicular helper cells and T follicular regulatory cells in rheumatic diseases[J].Nat Rev Rheumatol. 2019, 15(8):475-490.

[2]Chen Liu, Dongwei Wang, Songsong Lu, et al.Increased Circulating Follicular Treg Cells Are Associated With Lower Levels of Autoantibodies in Patients With Rheumatoid Arthritis in Stable Remission.Arthritis Rheumatol. 2018, 70(5):711-721

Disclosure of Interests:

None declared

THU0325 REDUCED OF TREG CELLS ASSOCIATED WITH THE DISEASE ACTIVITY OF ANCA-ASSOCIATED VASCULITIS

Background:

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a group of autoimmune disease that can cause systemic organ damage, characterized with the presence of abnormal antibodies (ANCAs) in the circulation and the small- and medium-vessel vasculitis[1].However,the etiology of AAV remained unclear. Several observations have showed that the breakdown of immune tolerance caused by many complex interactions was involved in the pathogenesis of AAV[2].It has been confirmed that the disorder of the CD4+T cell,especially the imbalance of Th17 and Treg cells can destroy the immune tolerance and cause many autoimmune disease[3]. But the relationship between the Th17/Treg and AAV is unknown.

Objectives:

We investigated the absolute numbers of CD4+T subsets cells in peripheral blood of patients with AAV and healthy adults,and then compared them in different disease activity of AAV to explore the role of CD4+T subsets cells in the pathogenesis and development of AAV.

Methods:

49 patients with AAV,hospitalized at the Second Hospital of Shanxi Medical University from the May 2016 to the November 2019 were enrolled, and 31 age and gender-matched healthy adults were anticipated as controls.According to BVAS, the patients were divided into disease-activity group (BVAS≥15, n=27) and non-disease-activity group (BVAS<15, n=22). The absolute numbers of CD4+T subsets cells including Th17 and Tregs in peripheral blood of these individuals were detected by flow cytometry.We analyzed whether there was difference of CD4+T subsets between the patients and healthy controls,and between disease-activity group and non-disease-activity group.

Results:

There was significant decreased level of Treg cells in the patients with AAV compared with healthy controls,especially in the disease-activity group. The absolute numbers of Treg cells was decreased in the patients with AAV compared with healthy controls (P<0.001) leading to a higher Th17/Treg ratio in the patients (P<0.01).Similarly,the absolute number of Treg cells was decreased in the disease- activity group (P<0.01) compared with the non-disease-activity group, and the absolute number of Treg cells was significant negative correlation with the disease activity indexes such as BVAS (r=-0.342,P=0.016), erythrocyte sedimentation rate(ESR) (r=-0.315,P=0.027) and C-reactive protein(CRP) (r=-0.305,P=0.033). But there was no statistically significant in the absolute number of Th17 cells between the patients and healthy controls, and between disease-activity group and non-disease-activity group.

Conclusion:

The results we investigated here suggested that the decreased number of Treg cells failed to control autoimmune inflammatory response and maintain immune tolerance, and the disease activity of AAV was associated with the reduced number of Treg cells.

Figure 1.

(A-C) Characteristics of the absolute number of Th17 cells and Treg cells in peripheral blood of healthy controls (n=31) and the patients with AAV (n=49). There was significant decreased level of Treg cells in the patients with AAV compared with healthy controls leading to a higher Th17/Treg ratio in the patients with AAV. (D-F) The absolute number of Treg cells was decreased in the disease- activity group (n=27) compared with the non-disease-activity group (n=21). The absolute number of Th17 cells and Treg cells was detected by flow cytometry. Statistical analyses were performed by the Mann-Whitney U test. *p<0.05,**p<0.01, ***p<0.001.

References:

[1]Cosmi, L., Th17 and Treg lymphocytes as cellular biomarkers of disease activity in Granulomatosis with Polyangiitis. Eur J Immunol, 2017.47(4): p. 633-636.

[2]Pagnoux, C.,Updates in ANCA-associated vasculitis.Eur J Rheumatol, 2016.3: p. 122-133.

[3]Diller, M.L., et al., Balancing Inflammation: The Link between Th17 and Regulatory T Cells. Mediators Inflamm, 2016.2016: p. 6309219.

Disclosure of Interests:

None declared

AB0630 IMBALANCE BETWEEN Th17 AND REGULATORY T CELLS IN PATIENTS WITH PM/DM COMBINED WITH EBV/CMV VIRAEMIA

Background:

Dermatomyositis and polymyositis (DM/PM) are associated with muscle weakness and inflammatory infiltration within the skeletal muscle. The numerical and functional defects of immune cells, due to long-term uses of glucocorticoids and disease-modifying anti-rheumatic drugs (DMARDs) together with immune disturbances associated with disease itself, lead to high risks in opportunistic infections, such as Epstein-Barr virus (EBV) and cytomegalovirus (CMV).1-2We want to observe changes of peripheral lymphcytessubsets in PM/DM patients with EBV and/or CMV infection,especially whether there is imblance between Th17 and Treg cells.

Objectives:

To investigate the characteristics of peripheral lymphocyte subsets in PM/DM with EBV and/or CMV infection, especially the Th17 and Treg cells.

Methods:

From February 2016 to November 2019, PM/DM patients with EBV and/or CMV viremia (infection group, n=34) and without infection (non-infection group, n=31) as well as healthy adult controls (n=20) were enrolled in our study. Absolute numbers of total T, total B, NK, CD4 + T, CD8 + T cells, and CD4 + T subsets (Th1, Th2, Th17 and Treg cells) in peripheral blood by flow cytometry combined with standard absolute counting beads.

Results:

(1) Compared with PM/DM patients without infection, 34 PM/DM patients with EBV and/or CMV infection, including 12 patients with EBV, 20 patients with CMV, 2 patients combined EBV and CMV, the absolute number of total T lymph cells (P=0.019), total B lymph cells (P=0.037), NK cells (P=0.033), CD4 + T cells (P=0.000), Th1 cells (P=0.014), Th2 cells (P=0.003), Th17 cells (P=0.003), Treg cells (P=0.004) lower than its of (P=0.003) patients without infection, the absolute number of CD8 + T cells (P=0.427) has no obvious difference between them.

(2) And its the absolute number of total T lymph cells (P=0.000), total B lymph cells (P=0.003), NK cells (P=0.000), CD4 + T cells (P=0.000), CD8 + T cells (P=0.006), Th1 cells (P=0.000), Th2 cells (P=0.001), Th17 cells (P=0.000) and Treg cells (P=0.000) significantly lower than healthy control.

(3) Compared with the healthy control,the absolute number of total T lymph cells (P=0.000), NK cells (P=0.000), CD4 + T cells (P=0.031), CD8 + T cells (P=0.000), Th1 cells (P=0.002), Th2 cells (P=0.031), and Treg cells (P=0.000) in PM/DM without infection evidently lower, but there is no siginificant difference in absolute number of total B lymph cells (P=0.19) and Th17 cells (P=0.171).

Conclusion:

We show that the absolute number of peripheral blood lymphocytes and CD4+T subsets in patients with PM/DM with EBV and/or CMV viremia is further reduced. In addition to Treg cells, a decrease in Th17 cells may also be an important feature of EBV and/or CMV infection in DM/PM. These cell reductions may be the cause and risk indicator of viral infections.

References:

[1]Yang X, Hao Y, Zhang X, et al. Mortality of Chinese patients with polymyositis and dermatomyositis. Clin Rheumatol. 2020 Jan 4. doi: 10.1007/s10067-019-04910-w. [Epub ahead of print]. PMID: 31902027

[2]Matsushita T,Kobayashi T, Kano M, et al. Elevated serum B-cell activating factor levels in patients with dermatomyositis: Association with interstitial lung disease. J Dermatol.2019:46:1190-6. doi:10.1111/1346-8138.15117

Figure.

Absolute numbers of peripheral lymphocyte subsets between healthy controls and patients were assessed by fow cytometry using oneplatform method. PM/DM infection group (n=34), PM/DM non- infection group(n=31)and healthy control group (n = 20).(*p<0.05, **p<0.01, ***p<0.001)

Disclosure of Interests:

None declared

Hsp90β positively regulates μ-opioid receptor function

AIMS

Many μ-opioid receptor (MOR)-associated proteins can regulate the MOR signaling pathway. Using a bacterial two-hybrid screen, we found that the C-terminal of the MOR associated with heat shock protein 90 isoform β (Hsp90β). Here, we explored the effect of Hsp90β on MOR signaling transduction and function.

MAIN METHODS

The interaction of Hsp90β with MOR was detected by co-immunoprecipitation and immunofluorescence. The effects of Hsp90β on MOR signaling induced by opioids were studied in vitro and in vivo. The effects of the Hsp90β inhibitor 17-N-allylamino-17-demethoxygeldanamycin (17-AAG) on morphine tolerance and dependence were studied via a hot plate test and CPP test.

KEY FINDINGS

Hsp90β, instead of Hsp90α, interacted with the MOR in HEK293 cells and SH-SY5Y cells, and the interaction was augmented after morphine pretreatment. The interaction of Hsp90β and MOR increased the inhibition of cAMP and decreased PKA activity under opioid treatment. The functional Hsp90β-MOR complex also promoted the phosphorylation and internalization of the MOR induced by DAMGO in MOR-CHO cells. 17-AAG blocked Hsp90β-MOR interactions and decreased the effect of Hsp90β on the MOR signal transduction. In C57BL/6 mice, 17-AAG decreased morphine-induced acute anti-nociception in the hot plate test, with an increase in phosphorylated PKA and phosphorylated JNK and a decrease in phosphorylated CREB and phosphorylated ERK in murine brains. Chronic morphine treatment induced tolerance, and dependence was inhibited by 17-AAG co-administration.

SIGNIFICANCE

Hsp90β is a positive co-regulator of the MOR via the activation of a G-protein-dependent and β-arrestin-dependent pathway. Hsp90β has the potential to improve the pharmacologic profile of existing opiates. It is conceivable that in future clinical treatments, the Hsp90β inhibitor, 17-AAG, could decrease the tolerance and dependence in cancer patients induced by opioids.

Thick grain boundary induced strengthening in nanocrystalline Ni alloy

Grain refinement has been extensively used to strengthen metallic materials for decades. Grain boundaries act as effective barriers to the transmission of dislocations, consequently leading to strengthening. Conventional grain boundaries have a thickness of 1-2 atomic layers, typically ∼0.5 nm for most metallic materials. Here, we report, however, the formation of ∼3 nm thick grain boundaries in a nanocrystalline Ni alloy. In situ micropillar compression studies coupled with molecular dynamics simulations suggest that the thick grain boundaries are stronger barriers than conventional grain boundaries to the transmission of dislocations. This study provides a fresh perspective for the design of high strength, deformable nanostructured metallic materials.

Effectiveness of delayed-release dimethyl fumarate on patient-reported outcomes and clinical measures in patients with relapsing-remitting multiple sclerosis in a real-world clinical setting: PROTEC

Background

Patient-reported outcomes (PRO) and clinical outcomes give a broad assessment of relapsing-remitting multiple sclerosis (RRMS) disease.

Objective

The aim is to evaluate the effectiveness of delayed-release dimethyl fumarate (DMF) on disease activity and PROs in patients with RRMS in the clinic.

Methods

PROTEC, a phase 4, open-label, 12-month observational study, assessed annualized relapse rate (ARR), proportion of patients relapsed, and changes in PROs. Newly diagnosed and early MS (≤3.5 EDSS and ≤1 relapse in the prior year) patient subgroups were evaluated.

Results

Unadjusted ARR at 12 months post-DMF versus 12 months before DMF initiation was 75% lower (0.161 vs. 0.643, p < 0.0001) overall (n = 1105) and 84%, 77%, and 71% lower in newly diagnosed, ≤3.5 EDSS, and ≤1 relapse subgroups, respectively. Overall, 88% of patients were relapse-free 12 months after DMF initiation (84%, newly diagnosed; 88%, ≤3.5 EDSS; 88%, ≤1 relapse). PRO measures for fatigue, treatment satisfaction, daily living, and work improved significantly over 12 months of DMF versus baseline.

Conclusion

At 12 months after versus 12 months before DMF initiation, ARR was significantly lower, the majority of patients were relapse-free, and multiple PRO measures showed improvement (overall and for subgroups), suggesting that DMF is effective based on clinical outcomes and from a patient perspective.Clinical trial: A Study Evaluating the Effectiveness of Tecfidera (Dimethyl Fumarate) on Multiple Sclerosis (MS) Disease Activity and Patient-Reported Outcomes (PROTEC), NCT01930708, https://clinicaltrials.gov/ct2/show/NCT01930708.

Assessment and Confirmation of Species Difference in Nonlinear Pharmacokinetics of Atipamezole with Physiologically Based Pharmacokinetic Modeling

Atipamezole, an α ₂-adrenoceptor antagonist, displayed nonlinear pharmacokinetics (PK) in rats. The aim of this study was to understand the underlying mechanisms of nonlinear PK in rats and linear PK in humans and develop physiologically based PK models (PBPK) to capture and validate this phenomenon. In vitro and in vivo data were generated to show that metabolism is the main clearance pathway of atipamezole and species differences exist. Where cytochrome P450 (P450) was responsible for the metabolism in rats with a low Michaelis constant, human-specific UDP-glucuronosyltransferase 2B10- and 1A4-mediated N-glucuronidation was identified as the leading contributor to metabolism in humans with a high V _max capacity. Saturation of metabolism was observed in rats at pharmacologically relevant doses, but not in humans at clinically relevant doses. PBPK models were developed using GastroPlus software to predict the PK profile of atipamezole in rats after intravenous or intramuscular administration of 0.1 to 3 mg/kg doses. The model predicted the nonlinear PK of atipamezole in rats and predicted observed exposures within 2-fold across dose levels. Under the same model structure, a human PBPK model was developed using human in vitro metabolism data. The PBPK model well described human concentration-time profiles at 10-100 mg doses showing dose-proportional increases in exposure. This study demonstrated that PBPK is a useful tool to predict human PK when interspecies extrapolation is not applicable. The nonlinear PK in rat and linear PK in human were characterized in vitro and allowed the prospective human PK via intramuscular dosing to be predicted at the preclinical stage. SIGNIFICANCE STATEMENT: This study demonstrated that PBPK is a useful tool for predicting human PK when interspecies extrapolation is not applicable due to species unique metabolism. Atipamezole, for example, is metabolized by P450 in rats and by N-glucuronidation in humans that were hypothesized to be the underlying reasons for a nonlinear PK in rats and linear PK in humans. This was testified by PBPK simulation in this study.

[Value of serum HBV RNA in HBeAg-negative patients with chronic hepatitis B]

Objective: To analyze serum HBV-RNA levels in patients with chronic hepatitis B whose serum HBV-DNA has dropped to undetected levels after treatment with entecavir, and to explore the correlation between HBV-RNA level and liver biochemical parameters, which lay the research foundation for the clinical significance of new serological marker HBV-RNA. Methods: HBeAg negatively detected 107 cases with chronic hepatitis B whose serum HBV-DNA test results were lower than detection level for six consecutive months after receiving standard nucleoside therapy for more than 12 months were included. HBV-RNA level was detected by Perkin-Elmer reagent. HBV-DNA level was detected by Roche Cobas. Hitachi automatic biochemical analyzer was used to detect ALT and AST. Architect chemiluminescence analyzer was used to detect HBsAg, HBeAg, anti-HBe and anti-HBc. RStudio software was performed to analyze the correlation between HBV-RNA level and liver biochemical parameters. Logistic regression was used to analyze the independent factors influencing HBV-RNA level. Results: The positive detection rate of serum HBV-RNA in patients with chronic hepatitis B whose serum HBV-DNA had dropped to undetected levels after ETV treatment was 22.43%. HBsAg, ALT and AST levels in HBV-RNA positive group were slightly higher than HBV-RNA negative group, while anti-HBc levels were slightly higher in HBV-RNA negative group. There was no difference in the level of anti-HBe between the HBV-RNA negative and the positive group. Logistic regression analysis showed that anti-HBc was an independent factor influencing the level of HBV-RNA detection (P = 0.021). Conclusion: HBV-RNA can be detected in some patients with chronic hepatitis B whose serum HBV-DNA level has dropped to undetected levels after ETV treatment. Serum HBV-RNA only comes from the direct transcription of cccDNA, so it is better than HBV-DNA and HBsAg to reflect cccDNA level or activity. Anti-HBc, as an independent factor influencing the level of HBV-RNA, may be used in combination as a new marker to predict the efficacy of antiviral therapy.

R2-8018 reduces the proliferation and migration of non-small cell lung cancer cells by disturbing transactivation between M3R and EGFR

AIMS

The M3 muscarinic acetylcholine receptor (M3R) is a G protein-coupled receptor that is expressed in cases of non-small cell lung cancer (NSCLC). Previous studies demonstrated that M3R antagonists reduce the proliferation of NSCLC. However, how antagonists inhibit the NSCLC proliferation and migration is still little known. This study aims to investigate the mechanism of M3R involved in the growth of NSCLC.

MAIN METHODS

The CRISPR/Cas9 was used to knock out (KO) the M3R gene. A real-time cell analyzer (RTCA) was used to record the proliferation of NSCLC cells. The migration and cell cycle of NSCLC cells were evaluated with scratch test and flow cytometry (FCM), respectively. Antibody microarray analysis was performed to detect the expression of proteins after antagonizing M3R and knocking out of M3R, subsequently some of these important proteins were verified by western blot.

KEY FINDINGS

The proliferation and migration of NSCLC cells were inhibited by M3R antagonist R2-8018 and knocking out of M3R. Antagonism or knocking out of M3R reduced the phosphorylation of EGFR. Moreover, c-Src and β-arrestin-1 are involved in the mechanism of how the inhibition of M3R affects EGFR in NSCLC. Further study demonstrated that PI3K/AKT and MEK/ERK signal pathways are involved in M3R-induced EGFR transactivation in NSCLC, and the molecules involved in the cell cycle progression and migration of NSCLC cells were identified.

SIGNIFICANCE

This further understanding of the relationship between M3R and NSCLC facilitates the design of therapeutic strategy with M3R antagonist as an adjuvant drug for NSCLC treatment.

Crocin Protects Human Umbilical Vein Endothelial Cells from High Glucose-Induced Injury Via Inhibiting the Endoplasmic Reticulum Stress Response

BACKGROUND

Endothelial dysfunction plays a key role in diabetic atherosclerosis. High glucose (HG) is considered a stimulator in the development of diabetic atherosclerosis. The endoplasmic reticulum (ER) stress response is involved in HG-induced vascular injury. Crocin has antioxidative and antiapoptotic properties.

OBJECTIVE

The current study was to evaluate whether crocin can protect human umbilical vein endothelial cells (HUVECs) from HG-induced injury and explored the associated mechanism.

METHODS

HUVECs were treated with 33 mmol/L glucose as the HG condition. The endothelial protective effects of crocin were evaluated by comparison with the control groups.

RESULTS

The exposure of HUVECs to HG for 24 h remarkably induced the ER stress response and a sequence of injuries, as demonstrated an increase in the apoptotic cell number, the reactive oxygen species level and inflammatory cytokine generation, as well as a decline in vascular endothelial growth factor A expression. These changes were markedly alleviated by pretreating the HUVECs with either crocin or 4-phenylbutyrate (ER stress inhibitor) before exposure to HG.

CONCLUSION

Crocin exerted antioxidative, antiapoptotic, anti-inflammatory and proangiogenic effects in the HG-induced HUVEC injury model, which were probably mediated by a favorable modification of ER stress that requires further investigation.