Epidemiological investigations and locally determined genotype diversity of Mycoplasma synoviae in Central China from 2017 to 2019

Mycoplasma synoviae (M. synoviae) has been identified worldwide to cause respiratory diseases, infectious synovitis, airsacculitis, and eggshell apex abnormalities (EAA) in commercial chickens, which results in substantial economic losses to the poultry industry. Therefore, in this study, 258 flocks were investigated between 2017 and 2019 for M. synoviae by screening samples from Central China. Subsequently, 129 M. synoviae strains were isolated, with a positive rate of 50%. Moreover, a higher incidence of M. Synoviae infections was in layers (74.1%) than in broilers (20%) in this study. The 5′-end conserved segment of the variable lipoprotein hemagglutinin A (vlhA) gene of these isolates was then cloned and sequenced because it is a common genomic target identified so far for M. synoviae genotyping. Genotyping of all isolates was based on the phylogenetic analysis and length analysis of the proline-rich-repeat (PRR) regions, respectively. Phylogenetic analysis based on 5′-end conserved segment of the vlhA gene (76–421 nt) assigned the majority of the occurring strains as being from group 6, and others from groups 2 and 3. Results identified that these isolates were of 6 types: A (38aa), D (23aa), E (19aa), I (28aa), J (20aa), and L (35aa), based on the size of the PRR region analysis. Furthermore, most of the isolates (81.4% were identified as type L. Additionally, the epidemic types included only I and L in 2017; however, the types rose to 5 (A, D, E, I, L) in 2018 and rose to 6 (A, D, E, I, J, L) in 2019. These data showed the genotype diversity of M. synoviae in Central China. The high rate of positive flocks suggests the urgent need to take real-time supervisory controls of this Mycoplasma species in avian flocks.

CRISPR/Cas9-mediated knockout of SGLT1 inhibits proliferation and alters metabolism of gastric cancer cells

BACKGROUND

The roles played by sodium/glucose cotransporters 1 (SGLT1) that transport glucose in cells independent of extracellular glucose concentration in gastric cancer are unknown.

METHODS

The expression of SGLT1 in 75 primary gastric cancer and paired adjacent normal tissue specimens was determined. Also, the underlying mechanism of the altered SGLT1 expression and its impact on the proliferation of the gastric cancer cells and their metabolism were investigated.

RESULTS

SGLT1 expression was found to be positively associated with pT, pN, TNM staging, histological differentiation, and a worse overall survival. CRISPR/Cas9 mediated knockout of SGLT1 could inhibit proliferation of gastric cancer cells, promote their apoptosis, and could also alter the metabolism of gastric cancer cells. Mechanistically, the transcription activity of SGLT1 could be negatively regulated by p53.

CONCLUSIONS

Besides identifying the important role of SGLT1 in gastric cancer, the underlying regulation mechanism in play was also elucidated. These make SGLT1 a promising new molecular target for the design of novel therapeutic modalities to control gastric cancer.

Combinatorial Analysis of AT-Rich Interaction Domain 1A and CD47 in Gastric Cancer Patients Reveals Markers of Prognosis

Background: The AT-rich interaction domain 1A (ARID1A) is thought to be a tumor suppressive gene, and most of its mutations result in loss of expression of ARID1A protein. Combined with SIRPα on the surface of macrophages, CD47 on the surface of cancer cells can send an antiphagocytic "Don't eat me" signal to the immune system that helps to avoid immune surveillance. However, the relationship between ARID1A and CD47 expression and their prognostic value in gastric cancer (GC) are still unknown. Methods: In this study, we evaluated ARID1A and CD47 expression in 154 GC patients' tissues using tissue microarray. Expressions of ARID1A and CD47 in GC cell lines were determined by western blot and quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) techniques, and cell membranous CD47 expression was quantified by flow cytometry. In addition, chromatin immunoprecipitation (ChIP)-qPCR was used to determine the aspects of regulation of CD47 by ARID1A. The proportions of tumor-infiltrating immune cells were estimated on The Cancer Genome Atlas (TCGA) data set by using quanTIseq and EPIC algorithms. The infiltration of M1-polarized macrophages, M2-polarized macrophages, and regulatory T cells (Tregs) in GC tissues was determined by multispectral immunofluorescence. Results: A significant correlation was found between loss of ARID1A and high expression of CD47 at protein level in GC. By integrating 375 bulk RNA sequencing samples from TCGA data set, we found that mutated ARID1A correlated with high CD47 expression. In GC cell lines, knockdown of ARID1A significantly increased CD47 expression both at protein and mRNA levels as measured by western blot, qRT-PCR, and flow cytometry. Moreover, ChIP-qPCR revealed that CD47 was a direct downstream target gene of ARID1A in GC. Utilizing univariate and multivariate survival analyses, we found that patients with ARID1AlossCD47high expression had a worse prognosis. Estimation of infiltrating immune cells on TCGA data set showed that a higher infiltration proportion of M2 macrophages and Tregs was found in ARID1A mutated CD47 high expression subgroup. Furthermore, application of multispectral immunofluorescence revealed a higher infiltration proportion of M2 macrophages and Tregs in ARID1AlossCD47high GC tissues. Conclusion: Loss of ARID1A is strongly correlated with high CD47 expression in GC, and combination of ARID1A and CD47 is a promising prognosis factor in GC.

Radiomic Signature as a Diagnostic Factor for Classification of Histologic Subtypes of Lung Cancer

<sec> <title>Objectives:</title> To discuss the application of radiomics using Computerized Tomography (CT) analysis, for improving its diagnostic efficacy in lung, specifically in distinguishing Squamous Cell Carcinoma (SCC), lung Adenocarcinoma (ADC), and Small Cell Lung Cancer (SCLC). </sec> <sec> <title>Methods:</title> The pathology of 189 identified cases of lung cancer was analyzed, retrospectively (60 patients with SCC, 69 patients with lung ADC and 60 patients with SCLC). A neural network was used to determine whether the pulmonary or mediastinal window was selected to extract effective radiomic features. The key features of radiomic signature were retrieved by a Least Absolute Shrinkage and Selection Operator (LASSO) multiple logistic regression model. Next, receiver operating characteristic curve and Area Under the Curve (AUC) analysis were used to evaluate the performance of the radiomic signature in both, training(129 patients) and validation cohorts (60 patients). </sec> <sec> <title>Results:</title> About 295 features were extracted from a manually outlined tumor region. Features extracted from mediastinal window CT scans had a better prognostic ability than pulmonary window scans. The average accuracy for mediastinal window scans was 0.933. Our analysis revealed that the radiomic features extracted from mediastinal window scans had the potential to build a prediction model for distinguishing between SCC, lung ADC, and SCLC. The performance of the radiomic signature to diagnose SCC and SCLC in validation cohorts proved effective, with AUC values of 0.869 and 0.859, respectively. </sec> <sec> <title>Conclusions:</title> A unique radiomic signature was constructed as a diagnostic factor for different histologic subtypes of lung cancer. Patients with lung cancer may benefit from this proposed radiomic signature. </sec>

Tracking cancer lesions on surgical samples of gastric cancer by artificial intelligent algorithms

To quickly locate cancer lesions, especially suspected metastatic lesions after gastrectomy, AI algorithms of object detection and semantic segmentation were established. A total of 509 macroscopic images from 381 patients were collected. The RFB-SSD object detection algorithm and ResNet50-PSPNet semantic segmentation algorithm were used. Another 57 macroscopic images from 48 patients were collected for prospective verification. We used mAP as the metrics of object detection. The best mAP was 95.90% with an average of 89.89% in the test set. The mAP reached 92.60% in validation set. We used mIoU for evaluation of semantic segmentation. The best mIoU was 80.97% with an average of 79.26% in the test set. In addition, 81 out of 92 (88.04%) gastric specimens were accurately predicted for the cancer lesion located at the serosa by ResNet50-PSPNet semantic segmentation model. The positive rate and accuracy of AI prediction were different based on cancer invasive depth. The metastatic lymph nodes were predicted in 24 cases by semantic segmentation model. Among them, 18 cases were confirmed by pathology. The predictive accuracy was 75.00%. Our well-trained AI algorithms effectively identified the subtle features of gastric cancer in resected specimens that may be missed by naked eyes. Taken together, AI algorithms could assist clinical doctors quickly locating cancer lesions and improve their work efficiency.

First report of a novel goose astrovirus outbreak in Muscovy ducklings in China

A highly acute disease characterized as visceral gout broke out in Muscovy ducklings in Henan province (China) in June 2020, with a mortality rate of up to 61%. In this study, common pathogenic agents were screened using reverse-transcription polymerase chain reaction or polymerase chain reaction. The results found the novel goose astrovirus (GoAstV) to be the pathogenic agent. We isolated the GoAstV, which has been designated as HNNY0620, using the Leghorn male chicken hepatocellular carcinoma (LMH) cell line and sequenced the complete genome. The phylogenetic tree showed that the amino acid (aa) sequences of ORF1a and ORF2 and the completed nucleotide sequences of the HNNY0620 strain were clustered in the GoAstV-I clade. ORF1a aa and whole-genome sequences were genetically close to TAstV-2 and DHV-3, whereas the ORF2 aa sequences were clustered with TAstV-2 and DHV2. Both the duck-origin GoAstVs and HNNY0620 harbored some special mutations, but ORF1a in 700 (I/T), ORF1b in 288 (F/L), and ORF2 in 306 (A/T) were only found in HNNY0620. These results suggest that the host range of GoAstV is diffusing, which can potentially affect other waterfowl.

The clinical application of PIVKA-II in hepatocellular carcinoma and chronic liver diseases: A multi-center study in China

BACKGROUND

Due to the absence of specific symptoms and low survival rate, efficient biomarkers for hepatocellular carcinoma (HCC) diagnosis are urgently required. The purpose of this study was to evaluate the diagnostic performance of protein induced by vitamin K absence or antagonist-II (PIVKA-II) and to determine the optimal cutoff values for HBV infection-related HCC.

METHODS

We conducted a cross-sectional, multi-center study in China to ascertain the cutoff value for HCC patients in the context of CHB- and HBV-related cirrhosis. The receiver operating characteristic curve (ROC) and the area under the curve (AUC) were used to evaluate the diagnostic performance of PIVKA-II.

RESULTS

This study enrolled 784 subjects and demonstrated that PIVKA-II had a sensitivity of 84.08% and a specificity of 90.43% in diagnosis HCC from chronic liver diseases. PIVKA-II at a cutoff of 37.5 mAU/mL yielded an AUC of 0.9737 (sensitivity 91.78% and specificity 96.30%) in discriminating HCC from chronic hepatitis B (CHB) patients. PIVKA-II at a cutoff of 45 mAU/mL yielded an AUC of 0.9419 (sensitivity 77.46% and specificity 95.12%) in discriminating HCC- from HBV-related cirrhosis patients. Furthermore, using a cutoff value of 40 mAU/mL for PIVKA-II as an HCC marker, only 4.81% (15/312) was positive in chronic hepatitis and 12.80% (37/289) in cirrhosis patients, revealing the satisfactory specificity of PIVKA-II in chronic liver disease of different etiologies.

CONCLUSION

Our data indicated that PIVKA-II had satisfactory diagnostic efficiencies and could be used as a screening or surveillance biomarker in HCC high-risk population.

Use of transanal drainage tube to prevent anastomotic leakage: intangible differences between the East and the West

Trans-anal drainage tube is used to reduce the rectal pressure, especially at the anastomotic site and thus to protect the anastomosis. Ideally it serves as and even may replace a diverting stoma. When compared to no treatment, the effectiveness of TDT seems confirmed based on the literature, but it remains uncertain whether TDT can replace the diverting stoma. Despite the insignificant tangible costs of TDT, it seems different cultures put varied weight on the intangible costs such as discomfort and pain to patients after surgery.

Application and research progress of phase change materials in biomedical field

Phase change materials (PCMs) are widely used in solar energy utilization, industrial waste heat recovery and building temperature regulation. However, there have been few studies on the application of PCMs in the field of biomedicine. In recent years, some scholars have carried out research in the biomedicine field using the characteristics of PCMs. It was observed that the excellent properties of PCMs enhance the quality of a variety of biomedical applications with many advantages over existing applications, which provide new methods for the treatment of disease. PCMs have broad application prospects in the field of biomedicine. Therefore, a timely review of relevant research progress is of great significance for the continuous development of new methods. Innovatively, from the unique perspective of the biomedical field, this paper systematically reviews the application and related research progress of PCMs from four aspects: cold chains for vaccines and medicines, drug delivery systems, thermotherapy/cold compress therapy and medical dressings. In addition, we summarize and discuss the general principles of the design and construction of PCMs in the biomedical field. Finally, existing problems, solutions and future research directions are also put forward in order to provide a basis for guidance and promote the future applications of phase change materials in the biomedicine field.

Two atypical gram-negative bacteria-binding proteins are involved in the antibacterial response in the pea aphid (Acyrthosiphon pisum)

The activation of immune pathways is triggered by the recognition of pathogens by pattern recognition receptors (PRRs). Gram-negative bacteria-binding proteins (GNBPs)/β-1,3-glucan recognition proteins (βGRPs) are a conserved family of PRRs in insects. Two GNBPs are predicted in the genome database of pea aphids; however, little is known about their functions in the aphid immune system. Here, we show that pea aphid GNBPs possess domain architectures and sequence features distinct from those of typical GNBPs/βGRPs and that their expression is induced by bacterial infection. Knockdown of their expression by dsRNA resulted in lower phenoloxidase activity, higher bacterial loads and higher mortality in aphids after infection. Our data suggest that these two atypical GNBPs are involved in the antibacterial response in the pea aphid, likely acting as PRRs in the prophenoloxidase pathway.

Identification of KRAS G12V associated clonal neoantigens and immune microenvironment in long-term survival of pancreatic adenocarcinoma

Objective

To investigate the molecular characteristics in tumor immune microenvironment that affect long-term survival of patients with pancreatic adenocarcinoma (PAAD).

Methods

The tumor related genetic features of a female PAAD patient (over 13-year survival) who suffered from multiple recurrences and metastases, and six operations over one decade were investigated deeply. Genomic features and immune microenvironment signatures of her primary lesion as well as six metastatic tumors at different time-points were characterized.

Results

High-frequency clonal neoantigenic mutations identified in these specimens revealed the significant associations between clonal neoantigens with her prognosis after each surgery. Meanwhile, the TCGA and ICGC databases were employed to analyse the function of KRAS G12V in pancreatic cancer.

Conclusions

The genomic analysis of clonal neoantigens combined with tumor immune microenvironment could promote the understandings of personalized prognostic evaluation and the stratification of resected PAAD individuals with better outcome.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00262-021-03012-4.

STAT3/HIF-1α signaling activation mediates peritoneal fibrosis induced by high glucose

BACKGROUND

Epithelial-mesenchymal transition (EMT) of mesothelial cells is a key step in the peritoneal fibrosis (PF). Recent evidence indicates that signal transducer and activator of transcription 3 (STAT3) might mediate the process of renal fibrosis, which could induce the expression of hypoxia-inducible factor-1α (HIF-1α). Here, we investigated the effect of STAT3 activation on HIF-1α expression and the EMT of mesothelial cells, furthermore the role of pharmacological blockade of STAT3 in the process of PF during peritoneal dialysis (PD) treatment.

METHODS

Firstly, we investigated the STAT3 signaling in human peritoneal mesothelial cells (HPMCs) from drained PD effluent. Secondly, we explored the effect of STAT3 signaling activation on the EMT and the expression of HIF-1α in human mesothelial cells (Met-5A) induced by high glucose. Finally, peritoneal fibrosis was induced by daily intraperitoneal injection with peritoneal dialysis fluid (PDF) so as to explore the role of pharmacological blockade of STAT3 in this process.

RESULTS

Compared with the new PD patient, the level of phosphorylated STAT3 was up-regulated in peritoneal mesothelial cells from long-term PD patients. High glucose (60 mmol/L) induced over-expression of Collagen I, Fibronectin, α-SMA and reduced the expression of E-cadherin in Met-5A cells, which could be abrogated by STAT3 inhibitor S3I-201 pretreatment as well as by siRNA for STAT3. Furthermore, high glucose-mediated STAT3 activation in mesothelial cells induced the expression of HIF-1α and the profibrotic effect of STAT3 signaling was alleviated by siRNA for HIF-1α. Daily intraperitoneal injection of high-glucose based dialysis fluid (HG-PDF) induced peritoneal fibrosis in the mice, accompanied by the phosphorylation of STAT3. Immunostaining showed that phosphorylated STAT3 was expressed mostly in α-SMA positive cells in the peritoneal membrane induced by HG-PDF. Administration of S3I-201 prevented the progression of peritoneal fibrosis, angiogenesis, macrophage infiltration as well as the expression of HIF-1α in the peritoneal membrane induced by high glucose.

CONCLUSIONS

Taken together, these findings identified a novel mechanism linking STAT3/HIF-1α signaling to peritoneal fibrosis during long-term PD treatment. It provided the first evidence that pharmacological inhibition of STAT3 signaling attenuated high glucose-mediated mesothelial cells EMT as well as peritoneal fibrosis.

[Heat stress induces neuronal apoptosis by up-regulating endoplasmic reticulum stress pathway]

OBJECTIVE

To explore the role of endoplasmic reticulum stress in heat stress-induced apoptosis of human neuroblastoma SH-SY5Y cells.

OBJECTIVE

SH-SY5Y cells were incubated at 43 ℃ for 2 h followed by further culture at 37 ℃ for 0, 3 h, or 6 h. With the cells cultured at 37 ℃ as the control, the cells exposed to heat stress were examined for morphological changes under optical microscope and changes in cell viability using CCK-8 assay. Flow cytometry was performed for detecting apoptosis of the cells following heat stress, and intracellular Ca²⁺ level in the cells was determined using flow cytometry and immunofluorescence confocal microscopy. The mRNA expression levels of caspase-12, BIP and XBP-1 in the cells were detected using qRT-PCR, and the protein expressions of caspase-12, BIP, P-JNK, JNK and XBP-1 were examined using Western blotting. The effect of pretreatment with 4-PBA on cell apoptosis following heat stress was analyzed with Western blotting.

OBJECTIVE

SH-SY5Y cells showed obvious cell shrinkage immediately after the exposure to heat stress, followed then by gradual cell stretching over time. The cell viability decreased significantly after heat stress (P=0.001), and the intracellular Ca²⁺ level increased significantly at 0 h and gradually recovered the normal level at 3 and 6 h. Heat stress induced significant increase in the protein expression of cleaved caspase-3 and time-dependent increase of caspase-12 (P=0.002) and BIP (P=0.008) expression at both the protein and mRNA levels. The expression of P-JNK/JNK protein increased significantly at 0 h (P=0.003) followed by gradual decrease; the expression levels of XBP-1 protein and mRNA gradually decreased after heat stress (P=0.005, P=0.002). Pretreatment with 4-PBA significantly reduced the expression level of cleaved caspase-3 in SH-SY5Y cells following heat stress.

OBJECTIVE

Heat stress induces apoptosis of SH-SY5Y cells by triggering endoplasmic reticulum stress and the imbalance of intracellular calcium ion homeostasis.

POS0788 CIRCULATING EXOSOMES PROMOTE LUPUS NEPHRITIS IN MRL-LPR MICE

Background:

Systemic Lupus Erythematosus (SLE) is a prototypic autoimmune disease that characterized by the loss of self-tolerance and the production of autoantibodies (autoAbs) [1, 2]. Lupus nephritis (LN), the severe organ-threatening manifestations of SLE, could cause massive damage to patients[3, 4]. Currently, some exosomal microRNAs (miRNAs) are considered as potential biomarkers in SLE. However, the role of exosomal miRNAs in Lupus Nephritis (LN) remains unclear.

Objectives:

The purpose of this study was to investigate molecular mechanism of plasma exosomal miRNAs in the development of Lupus Nephritis.

Methods:

Circulating exosomes were isolated from plasma of patients with LN, SLE without LN (NLN). Plasma exosomes were authenticated by Western Blot, Nanosight Tracking Analysis (NTA) and transmission electron microscopy (TEM). Fluorescence microscopy of co-cultured plasma exosomes and podocytes demonstrated that exosomes were uptaken into podocytes. Moreover, cell apoptosis and the inflammation factors was assessed using Western Blot. We analyzed the expression profiles of miRNAs in LN and NLN exosomes and the expression profiles of mRNAs of podocytes stimulated with LN and NLN exosomes with the help of next generation sequencing (NGS).

Results:

We demonstrate that exosomes derived from LN plasma could be taken by neighboring podocytes and promote the apoptosis of podocytes and the expression of inflammation factors. In addition, the sequencing found that miRNAs were differentially expressed in LN and NLN exosomes and mRNAs were differentially expressed in podocytes stimulated with LN and NLN exosomes.

Conclusion:

LN plasma exosomes have a potency to stimulate the apoptosis of podocytes and the expression of inflammation factors. Moreover, differentially expressed miRNAs in exosomes play a potential role in the development of LN.

References:

[1]T. Colasanti, A. Maselli, F. Conti, M. Sanchez, C. Alessandri, C. Barbati, D. Vacirca, A. Tinari, F. Chiarotti, A. Giovannetti, F. Franconi, G. Valesini, W. Malorni, M. Pierdominici, E. Ortona, Autoantibodies to estrogen receptor α interfere with T lymphocyte homeostasis and are associated with disease activity in systemic lupus erythematosus, Arthritis and rheumatism, 64 (2012) 778-787.

[2]H.A. Al-Shobaili, A.A. Al Robaee, A.A. Alzolibani, Z. Rasheed, Antibodies against 4-hydroxy-2-nonenal modified epitopes recognized chromatin and its oxidized forms: role of chromatin, oxidized forms of chromatin and 4-hydroxy-2-nonenal modified epitopes in the etiopathogenesis of SLE, Disease markers, 33 (2012) 19-34.

[3]A. Kaul, C. Gordon, M.K. Crow, Z. Touma, M.B. Urowitz, R. van Vollenhoven, G. Ruiz-Irastorza, G. Hughes, Systemic lupus erythematosus, Nat Rev Dis Primers, 2 (2016) 16039.

[4]M.G. Tektonidou, A. Dasgupta, M.M. Ward, Risk of End-Stage Renal Disease in Patients With Lupus Nephritis, 1971-2015: A Systematic Review and Bayesian Meta-Analysis, Arthritis & rheumatology (Hoboken, N.J.), 68 (2016) 1432-1441.

Disclosure of Interests:

None declared

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

Background:

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

Objectives:

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

Methods:

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

Results:

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

Conclusion:

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

References:

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

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

Acknowledgements:

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

Disclosure of Interests:

None declared

POS0787 BERBERINE MODULATE LUPUS SYNDROME VIA THE REGULATION OF GUT MICROBIOTA IN MRL/LPR MICE

Background:

Intestinal flora disorder and immune abnormalities have been reported in systemic lupus erythematosus (SLE) patients1,2. Berberine (BBR) showed significant effects in regulating the intestinal flora, repairing gut barriers and regulating immune cells3,4. While few reports mentioned the abnormal gut microbiota and metabolites in Chinese SLE patients.

Objectives:

Our investigation tried to illustrate the relationship between gut microbiota, intestinal metabolites and disease activity in Chinese SLE patients. And the effect of BBR to intestinal dysbacteriosis, multiple organ damages and over-activated immune system in MRL/Lpr mice.

Methods:

16S high-throughput (16S rRNA) sequence, qRT-PCR and gas chromatography technology were used to determine the gut microbiota and metabolites in 104 SLE patients from Affiliated Hospital of Nantong University, China. BBR was orally treated to the MRL/Lpr mice in low, medium and high doses. After 6 weeks treatment, mice were sacrificed. Serum, faeces and organs were collected for further studies.

Results:

Chinese SLE patients showed higher abundance of Bacteroidetes and lower abundance of Firmcutes. The results of qRT-PCR showed high Firmcutes/Bacteroidetes (F/B) ratio of SLE patients. The F/B ratio was negative correlated with SLE disease activity index (SLEDA) score. Almost all the tested short-chain fatty acids (SCFAs) found statistically significant results in SLE and LN (lupus nephritis) patients, especially the propanoic acid and butyric. BBR altered the relative abundance of Bacteroides and Verrucomicrobia and the butyric acid content in colon of MRL/Lpr mice. The increase of tight junction protein also indicated the gut barrier was repaired by BBR. Treg and Tfr cells in spleen and mesenteric lymph node (MLN) were increased. These results revealed a positive therapeutic effect of berberine on SLE from gut microbiota to immune status.

Conclusion:

Our study highlights current status of intestinal dysbacteriosis in Chinese patients with SLE and differences in intestinal metabolites among patients with different disease states. The regulation of intestinal flora and the repairment of gut barrier by intestinal metabolites in BBR treated mice seemed to be the factor that directed the immune responses and disease outcomes. The ultimate goal of our study was to determine the beneficial effects of regulating the gut microbiota on the treatment of SLE. The application of berberine is a relatively safe and convenient way. In the coming investigations, we plan to focus on the study of berberine and its metabolites on intestinal function and systemic immunity.

References:

[1]Guo, M. et al. Alteration in gut microbiota is associated with dysregulation of cytokines and glucocorticoid therapy in systemic lupus erythematosus. Gut microbes11, 1758-1773, doi:10.1080/19490976.2020.1768644 (2020).

[2]Mu, Q. et al. Control of lupus nephritis by changes of gut microbiota. Microbiome5, 73, doi:10.1186/s40168-017-0300-8 (2017).

[3]Habtemariam, S. Berberine pharmacology and the gut microbiota: A hidden therapeutic link. Pharmacological research155, 104722, doi:10.1016/j.phrs.2020.104722 (2020).

[4]Cui, H. et al. Berberine Regulates Treg/Th17 Balance to Treat Ulcerative Colitis Through Modulating the Gut Microbiota in the Colon. Frontiers in pharmacology9, 571, doi:10.3389/fphar.2018.00571 (2018).

Figure 1.

Disclosure of Interests:

None declared

POS0761 INVESTIGATION ON THE EFFECT AND MECHANISM OF ABNORMALLY ACTIVATED CD8+ T CELLS FROM BONE MARROW ON HEMATOPOIETIC STEM CELLS IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

Background:

SLE is an autoimmune disease characterized by the abnormal function of lymphocytes. The impairment of hematopoietic function of bone marrow participates in its pathogenesis, in which T cells play an important role. However, study on bone marrow T cells in SLE patients is very limited.

Objectives:

This study aims to characterize the phenotype and molecular characteristics of abnormally activated CD8+T cells in bone marrow of SLE patients and explore the mechanism of hematopoietic stem cells (HSCs) reduction caused by the abnormally activated CD8+T cells in bone marrow of patients with SLE.

Methods:

A total of 8 SLE patients and 5 age- and sex-matched controls were recruited in our study. Among them, 3 SLE patients and 4 donors were collected bone marrow and peripheral blood samples for Single-cell RNA sequencing (scRNA-seq) and functional studies. BM and peripheral T cell subsets were measured by flow cytometry. Plasma cytokines and secreted immunoglobulins were detected by Luminex. Disease activity of SLE patients was measured using the SLE Disease Activity Index (SLEDAI). All analyses were performed using R language and Flowjo 9.

Results:

In the present study, SLE patients had increased CD8+T%αβT cells and decreased CD4+T%αβT cells in bone marrow of SLE, compared to healthy controls. A large number of CD38+HLADR+CD8+T cells existed in the bone marrow and peripheral blood of SLE patients. Those patients also showed reduced number of HSCs, and with a downward trend of the numbers of peripheral red blood cells, white blood cells, neutrophils, hemoglobin, and platelets. By scRNA-seq, the CD38+HLADR+CD8+T cells contained high levels of GZMK, GZMA, PRF1, IFNG, and TNF in the bone marrow of SLE patients. the CD38+HLADR+CD8+T cells exhibited significant relationship with HSCs, white blood cells, neutrophils, and platelets.

Conclusion:

These findings demonstrated that the abnormally activated CD8+T cells in bone marrow can reduce the number of HSCs by the expression of killer molecules, which contributes to the impairment of hematopoietic function and the development of SLE. This project focuses on the specific bone marrow T cell subset in SLE. The completement of this project provides information for exploring the mechanism of hematopoiesis involvement.

References:

[1]Anderson E, Shah B, Davidson A, Furie R. Lessons learned from bone marrow failure in systemic lupus erythematosus: Case reports and review of the literature. Semin Arthritis Rheum. 2018;48(1):90-104.

[2]Sun LY, Zhou KX, Feng XB, Zhang HY, Ding XQ, Jin O, Lu LW, Lau CS, Hou YY, Fan LM. Abnormal surface markers expression on bone marrow CD34+cells and correlation with disease activity in patients with systemic lupus erythematosus. Clin Rheumatol. 2007;26(12):2073-2079.

Acknowledgements:

We want to thank Lu Meng, Teng Li, Wei Zhou, and Jiaxin Guo for their assistance with this study.

Disclosure of Interests:

None declared

AB0066 MECHANISMS OF TOTAL SAPONINS OF PANAX JAPONICUS MITIGATES COLLAGEN-INDUCED ARTHRITIS

Background:

Total saponins of Panax japonicus (TSPJ) are extracted from Panax japonicus (T.Nees) C.A.Mey and have achieved a good therapeutic effect in the treatment of rheumatoid arthritis (RA). Unfortunately, the mechanism of TSPJ acting on RA is not clear.

Objectives:

To investigate the potential mechanisms and key targets of TSPJ on RA.

Methods:

The raw data were downloaded from the Gene Expression Omnibus (GEO) database, and the RStudio3.6.1 software was used to identify differentially expressed genes (DEGs). The potential targets of active compounds from TSPJ were predicted by the Pharmmapper and SwissTargetPrediction databases. Based on the overlapping genes, we used Cytoscape 3.7.2 software to construct a protein-protein interactions (PPI) network and to determine the mechanisms of the treatment by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Collagen-induced arthritis (CIA) model was established and treated with different doses of TSPJ. Arthritis index (AI) and histology score were used to evaluate the symptoms of CIA. The levels of vascular endothelial growth factor (VEGF), hypoxia-inducible factor 1 (HIF-1), IL-1β, and IL-17A tested by enzyme linked immunosorbent assay and real time-quantitative Polymerase Chain Reaction.

Results:

A total of 2670 DEGs and 371 TSPJ targets were obtained, including 52 overlapping genes. 41 genes had protein interactions that are used to build the PPI network. The results of the KEGG enrichment analysis included VEGF and HIF-1 signaling pathway. Seven negative correlation genes and 16 positive correlation genes were obtained by correlational analysis of DEGs in VEGF and HIF-1 signaling pathway. SRC proto-oncogene, nonreceptor tyrosine kinase (SRC), and the signal transducer and the activator of transcription 3 (STAT 3) had a higher value of degree in PPI and showed a significant correlation in the pathways; they were regarded as key targets. Compared with the CIA model group, TSPJ significantly decreased the AI and histology scores. Moreover, the expression of VEGF-A, HIF-1α, IL-1β, and IL-17A in serum or spleens significantly reduced in a dose-dependent.

Conclusion:

Present study show that SRC and STAT 3 may be the key targets of TSPJ acting on the VEGF and HIF-1 signaling pathways, thus inhibiting angiogenesis and improving RA.

Disclosure of Interests:

None declared

POS0785 CHANGING EXPRESSION PROFILES OF LONG NONCODING RNAS, MIRNAS, MRNAS AND CIRCULAR RNAS IN LABIAL SALIVARY GLANDS OF PRIMARY SJÖGREN’S SYNDROME (PSS)

Background:

Primary Sjögren’s syndrome (pSS) is a relatively common autoimmune disease characterized by oral and ocular dryness. An increasing number of studies have revealed that long non-coding RNA (lncRNA), miRNA, mRNA and circular RNA (circRNA) contributes to the pathogenesis of autoimmune diseases.

Objectives:

To explore lncRNA, miRNA, mRNA and circRNA expression profiles in labial salivary glands (LSGs) in pSS patients and their biological functions in the regulation of pSS.

Methods:

The expression of 75,550 lncRNAs, 2,318 miRNA, 20,292 mRNAs and 6,877 circRNAs were determined in the LSG of six pSS patients and six healthy controls using microarray experiments. Validation was performed in pSS patients and controls using real-time PCR. LncRNA-mRNA co-expression and gene-pathway networks were constructed using bioinformatics software.

Results:

A total of 599 lncRNAs (upregulated: 279, downregulated: 320), 78 miRNAs (upregulated: 26, downregulated: 52), 615 mRNAs (upregulated: 590, downregulated: 25) and 160 mRNAs (upregulated: 110, downregulated: 50) were differentially expressed in the LSGs of pSS patients. Five of these lncRNAs were validated using real-time PCR. lncRNA HCP5, lncRNA SNHG5, lncRNA IFI44L, lncRNA CMPK2 were significantly upregulated and lncRNA TTYH1 were downregulated in pSS. GO and KEGG biological pathway analysis were performed to predict the functions of differentially expressed lncRNAs and co-expressed potential targeting genes. Subsequently, a ceRNA (lncRNA-miRNA-mRNA) network including 2320 ceRNA pairs was constructed based on predicted miRNAs shared by lncRNAs and mRNAs.

Conclusion:

The expression profile provided a systematic perspective on the potential functions of lncRNAs miRNAs, mRNAs and circRNAs in the pathogenesis of pSS. Therefore, this study will aid in the development of new diagnostic biomarkers and drug therapies.

References:

[1]Le Dantec C, Varin MM, Brooks WH, Pers JO, Youinou P, Renaudineau Y. Epigenetics and Sjogren’s syndrome.Curr Pharm Biotechnol. 2012 Aug;13(10):2046-53.

Disclosure of Interests:

None declared

Epigenomic analysis of biliary tract cancer identifies subtypes with different immune characteristics and clinical outcomes

e16153

Background: Biliary tract cancer (BTC) is an aggressive malignancy with poor prognosis and limited treatment options. The epigenome-associated multi-dimensional studies for BTC are limited. Here, we proposed a DNA methylation-based classification scheme and investigated the associations between methylation and multi-dimensional data including clinicopathological features, genetic aberrations, and prognosis. Methods: Multi-dimensional data concerning mutation, DNA methylation, and clinical data from 105 BTC patients who received surgical resection (gallbladder cancer [GBC], n=48, cholangiocarcinoma [CCA], n=57) were analyzed. Differentially methylated blocks (DMBs) in GBCs and CCAs were identified by comparing tumors and adjacent tissues. Methylation-based subtyping was performed via non-supervised consensus clustering. Results: The differentially methylated blocks (DMBs) in GBCs and CCAs are highly overlapping. Based on the common DMBs of GBCs and CCAs, the classifier yielded high sensitivity of 95.2% and specificity of 96.0%. Hypomethylated genes were enriched in pathways of transmemberane receptor and ion binding, while hypermethylation occurred in genes concerning DNA binding transcription activity. By non-supervised clustering of common DMBs, 6 clusters with different degrees of methylation change were identified. Higher methylation alteration (cluster risk-high) was associated with more copy number variation and shorter OS. By LASSO regression, a 12-gene prognostic model was trained and validated (Table). As for immune characteristics, the methylation of CD8A gene was lower in the cluster risk-high group, and this association was validated in the TCGA-cholangiocarcinoma cohort. In addition, lower methylation change was associated with higher BCR/TCR diversity, immune cell infiltration, and PD-L1 and CTLA4 mRNA expression. Conclusions: In BTC, methylation patterns may serve as a robust indicator of immune-related features and prognosis. Our integrative analysis highlights the association between genomic and epigenomic features, and provides insights into the molecular heterogeneity, and the potential therapeutic significance in biliary tract malignancies. Included methylation sites in the LASSO model.[Table: see text]

Comparative mutational analysis of biliary tract cancers

e16164

Background: Traditional classifications of tumors have utilized tissue of origin and histologic types. These categories have been refined with comprehensive molecular characterizations across large numbers of tumors. We hereby aimed to identify the similarities and differences of mutational profiles among the cancers along biliary tract, and investigate their prognostic effects. Methods: Mutation and clinical data from 99 BTC patients who received surgical resection (gallbladder cancer [GBC], n=42; cholangiocarcinoma [CCA], n=57) were analyzed. Capture-based targeted deep sequencing was performed using a 520-gene panel, spanning 1.64 Mb of the human genome (Burning Rock Biotech). Results: The mutational frequencies of TP53, BRCA1/2, ATM, and PI3K, WNT, HRR, and cell cycle pathway, gradually decreased with the order of the anatomical position (GBC, dCCA, pCCA, iCCA-large duct, and iCCA-small duct), while the changing trend of BRAF mutational frequency was the opposite (Table). In addition, CCND1/E1 and APC mutations were enriched in metastatic BTCs. As for prognostic effect, mutations of BRAF, TGFBR1/2, ARID1A, and MMR pathway were associated with shorter OS, and these association remained significant after adjustment for tissue of origin, TNM stage, histological grade, surgical margin, and serum CEA level. Conclusions: The differentially mutated genes among the cancers along biliary tract may indicate the potential mechanism of tumor development in different anatomic locations. Deeper understanding of the prognosis-related mutational events might change the postoperative management of BTC by enabling risk stratification, ACT monitoring, and early relapse detection. Mutational rate of the differentially mutated genes among the cancers along biliary tract.[Table: see text]

Optimizing the program of sequential chemotherapy for advanced gastric cancer based on gene-level CNVs called from ctDNA

e16068

Background: Tumor evolutionary trade-offs under treatment pressure can be utilized to optimize therapy. We aimed to profile the dynamic pattern of gene-level copy number variations (CNVs) for advance gastric cancer (GCA) patients who underwent sequential chemotherapy and optimized the therapy program. Methods: 27 chemo-naive advanced GCA patients with distant metastasis were enrolled. Peripheral blood samples were collected at different time points, including pre-therapy and disease progression on a specific regimen. Gene-level CNVs were called from ctDNA of blood samples and drug modified score (DMS) was defined as the ratio of CNV value between samples of pre- and post-treatment for each gene. Positive and negative DMS of a gene represented its resistance and sensitivity to a selected regimen, respectively. Then, the best initial regimen was selected and the optimal program of sequential chemotherapy was designed for each patient. Results: DMS of gene was calculated for four chemotherapy regimens, including platinum-based doublet regimen (Pt-2d), oral-fluorouracil prodrug (O-FP), paclitaxel-based regimen (PTX) and irinotecan-based regimen (CPT-11). Based on DMS distribution, resistant and sensitive genes were determined for each regimen through a heuristic method. Functional enrichment analysis showed that resistant genes mainly involved in cellular response to oxygen-containing compound and regulation of cell proliferation, while sensitive genes mainly involved in positive regulation of macromolecule biosynthetic process and regulation of apoptotic process. Then, drug resistant score (DRS, defined as DMS weighted sum of CNV values of resistant genes) was calculated and the regimen with the lowest DRS was selected as the best initial treatment for each patient. The best initial treatment of 16 patients was CPT-11, of 8 patients was O-FP, of 2 patients was Pt-2d and of 1 patient was PTX. Following that, the optimal program of sequential chemotherapy was designed according to the percentage of shared resistant genes between regimens for each patient, where two regimens with the lowest percentage were recommended to use one by one. Finally, prognostic analysis showed that differences between the optimal and practical program of sequential chemotherapy were negatively correlated to overall survival of patients. Conclusions: Based on gene-level CNVs called from ctDNA of blood samples, we determined the best initial treatment and designed the optimal program of sequential chemotherapy for advanced GCA patients, pacing a key step toward precision medicine in GCA field.