Clonal expansion of shared T cell receptors reveals the existence of immune commonality among different lesions of synchronous multiple primary lung cancer.

The increase in the detection rate of synchronous multiple primary lung cancer (MPLC) has posed remarkable clinical challenges due to the limited understanding of its pathogenesis and molecular features. Here, comprehensive comparisons of genomic and immunologic features between MPLC and solitary lung cancer nodule (SN), as well as different lesions of the same patient, were performed. Compared with SN, MPLC displayed a lower rate of EGFR mutation but higher rates of BRAF, MAP2K1, and MTOR mutation, which function exactly in the upstream and downstream of the same signaling pathway. Considerable heterogeneity in T cell receptor (TCR) repertoire exists among not only different patients but also among different lesions of the same patient. Invasive lesions of MPLC exhibited significantly higher TCR diversity and lower TCR expansion than those of SN. Intriguingly, different lesions of the same patient always shared a certain proportion of TCR clonotypes. Significant clonal expansion could be observed in shared TCR clonotypes, particularly in those existing in all lesions of the same patient. In conclusion, this study provided evidences of the distinctive mutational landscape, activation of oncogenic signaling pathways, and TCR repertoire in MPLC as compared with SN. The significant clonal expansion of shared TCR clonotypes demonstrated the existence of immune commonality among different lesions of the same patient and shed new light on the individually tailored precision therapy for MPLC.

mTORC1-GLUT1-mediated glucose metabolism drives hyperactivation of B cells in primary Sjogren's syndrome.

Primary Sjögren's syndrome (pSS) is a chronic systemic autoimmune disease characterized by B cell hyperactivation and hypergrammaglobulinemia. Currently, the role of metabolic pathways in the B cells of pSS patients is poorly defined. Here, we showed that upon cytosine phosphate-guanine (CpG)/sCD40L/IL-4 stimulation, B cells proportionally increased glycolysis and oxygen consumption, and compared with B cells from healthy controls (HCs), B cells from pSS patients exhibited higher glycolysis capacity and maximal oxidative respiration (OXPHOS). We also found that glucose transporter 1 (GLUT1) expression in B cells from pSS patients was significantly higher than that in B cells from HCs. Treatment with 2-deoxy-d-glucose (2-DG) inhibited the activation of B cells in pSS patients. Both 2-DG and Metformin inhibited the proliferation, formation of plasma/plasmablasts and decreased the IgG and IgM levels in the supernatants of B cells from pSS patients. Furthermore, inhibition of mTORC1 by rapamycin had an effect similar to that of 2-DG, suppressing B cell activation, proliferation and antibody production. Taken together, we demonstrated that B cells from pSS patients are more metabolically active than those from HCs and suggested that the mTORC1-GLUT1 glycolysis pathways were the major drivers of B cell hyperactivation and autoantibody production in pSS patients.

Efficacy and safety of tripterygium wilfordii Hook F plus TNF inhibitor for active rheumatoid arthritis: A multicentre, randomized, double-blind, triple-dummy controlled trial.

An investigator-initiated, multicentre, randomized, double-blind, triple-dummy, controlled trial was conducted at 14 tertiary rheumatology centers in China to evaluate the efficacy and safety of Tripterygium wilfordii Hook F (TwHF) with recombinant human TNF receptor IgGFc fusion protein (rhTNFR-Fc) in active Rheumatoid Arthritis (RA). Primary endpoint was the proportion of patients achieved a 50% improvement of American College of Rheumatology criteria (ACR50) in TwHF+rhTNFR-Fc vs. methotrexate (MTX) group at week 12. ACR50 was achieved in 57.1% (72/126), 41.3% (52/126), 23.0% (29/126), and 26.2% (33/126) patients receiving TwHF+rhTNFR-Fc, MTX + rhTNFR-Fc, TwHF and MTX monotherapy, respectively, at week 12 (TwHF+rhTNFR-Fc vs. other three groups, all p < 0.05). No statistical difference in serious adverse events or adverse events leading to discontinuation of study across all groups was documented. TwHF+rhTNFR-Fc was superior to MTX for active RA, and was more effective than MTX + rhTNFR-Fc on ACR50, with a similar safety profile. Trial registration:ClinicalTrials.govNCT03589833.

68Ga-FAPI PET/CT for Rheumatoid Arthritis: A Prospective Study.

Background In rheumatoid arthritis (RA), fibroblast-like synoviocyte cells, which are involved in inflammation of the articular cartilage and bone, overexpress fibroblast activation protein (FAP). This is a feature that could be leveraged to improve imaging assessment of disease. Purpose To determine the performance of gallium 68 (68Ga)-labeled FAP inhibitor (FAPI) in assessing joint disease activity of RA and to compare with fluorine 18 (18F) fluorodeoxyglucose (FDG) imaging. Materials and Methods Twenty participants with RA (15 women; mean age, 55 years ± 10 [SD]) were prospectively enrolled from September 2020 to December 2021 and underwent clinical and laboratory assessment of disease activity and dual-tracer PET/CT (68Ga-FAPI and 18F-FDG) imaging. Imaging-derived variables of PET joint count (the number of joints positive for RA at PET) and PET articular index (a sum of the points of the joints using a three-point scale) were correlated to clinical and laboratory variables of disease activity. Results The combined output of both PET/CT techniques helped detect 244 affected joints, all of which showed positive results at 68Ga-FAPI PET/CT. However, fifteen of 244 (6.1%) FAPI-avid joints in six of 20 (30%) participants were not detected at 18F-FDG PET/CT. The maximum standardized uptake value of the most affected joint in each participant was higher in 68Ga-FAPI than in 18F-FDG PET/CT (9.54 ± 4.92 vs 5.85 ± 2.81, respectively; P = .001). The maximum standardized uptake values of the joints at both 68Ga-FAPI and 18F-FDG PET/CT were positively correlated with laboratory evaluation of C-reactive protein levels (r = 0.49 [P = .03] and 0.54 [P = .01], respectively). The PET joint count and PET articular index scores at 68Ga-FAPI PET/CT were also positively correlated with most clinical disease activity variables and radiographic progression of joint damage (P < .05). Conclusion In participants with rheumatoid arthritis who underwent gallium 68 fibroblast activation protein inhibitor PET/CT, the extent of joint involvement correlated with clinical and laboratory variables of disease activity and showed a greater amount and degree of affected joints than at fluorine 18 fluorodeoxyglucose PET/CT. Clinical trial registration no. NCT04514614 © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Williams and Ahlman in this issue.

Cancer occurrence after SLE: effects of medication-related factors, disease-related factors and survival from an observational study.

OBJECTIVES: To explore the survival and risk factors for cancer occurrence after SLE (SLE-CA). METHODS: Patients with cancer diagnosed after SLE in Peking Union Medical College Hospital between January 2006 and September 2017 were recruited and followed. Data regarding medication-related and disease-related factors and survival were collected and compared with matched controls. Logistic regressions were applied to identify risk factors. The Kaplan-Meier method with a log-rank test was performed to evaluate survival. RESULTS: Forty-five SLE-CA patients and 128 controls were included, with the most common cancer site being the female genital system. SLE-CA patients were exposed to a higher cumulative dosage of CYC, with less mucocutaneous and haematologic involvement and higher anti-dsDNA positivity. At the time of cancer diagnosis, SLE-CA patients had lower SLEDAI 2000 (SLEDAI-2K), tended to achieve Definitions of Remission in SLE remission and minimal disease activity, but had higher SLICC/ACR Damage Index. Multivariable analysis identified high dosage of CYC [odds ratio (OR) 1.027, 95% CI 1.008, 1.046; P = 0.005] and low SLEDAI-2K at cancer diagnosis (OR 0.756, 95% CI 0.579, 0.986; P = 0.039) as risk factors. Mucocutaneous (OR 0.330, 95% CI 0.110, 0.991; P = 0.048) and haematologic involvement (OR 0.304, 95% CI 0.103, 0.902; P = 0.032) were negatively associated with cancer occurrence after SLE. The 5- and 10-year survival rates in SLE-CA patients were 95.2% and 92.1%, respectively. No significant difference of survival was observed between SLE-CA patients and controls (P = 0.177). CONCLUSION: High dosage of CYC and disease-related factors (low SLEDAI-2K, less mucocutaneous and haematologic involvement) were related factors for cancer occurrence after SLE, while no survival difference was observed.

Dietary patterns and life-styles of patients with gastrointestinal involvement of systemic lupus erythematosus: Questionnaire survey from a tertiary center of China.

OBJECTIVE: To investigate the dietary patterns and lifestyles of patients with lupus gastrointestinal (GI) involvement and to reveal the possible role of organ-specific involvement of systemic lupus erythematosus (SLE) on daily diet. METHODS: Patients with SLE complicated with gastrointestinal involvement (SLE-GI) admitted to Peking Union Medical College Hospital (PUMCH) from January 2010 to September 2021 were enrolled. Age- and sex-matched SLE patients with lupus nephritis (SLE-LN) but free of other internal organs involvement who were admitted during the same period were enrolled as disease controls at the ratio of 1:1. In addition, a group of age- and sex-matched healthy people were also included as healthy controls (HCs). Questionnaires were distributed to these patients and HC to collect their dietary patterns and lifestyle information. Clinical features, dietary and lifestyle habits were compared between the two groups of patients and HC. RESULTS: The questionnaire survey showed that compared with HC, the SLE-GI group had higher proportions of vegetarians (p = 0.014) and a lower proportion of omnivores (p = 0.058). A higher percentage of SLE-GI patients reported a traditional Chinese medicine (p = 0.018) taken history and surgical history (p = 0.014). They also less likely to take fried/pickled food (p = 0.042) and dietary supplements (p = 0.024) than HC. Higher percentages of SLE-GI patients and SLE-LN patients preferred self-catering (87.5% and 94.3%) over take-out food than HC (70.8%) (p = 0.127 and p = 0.016). No significant difference on drinking preference among the three groups, but it seemed more SLE-GI patients consumed yogurt than HC (p = 0.097). The SLE-LN patients were also found to have lower frequencies of staying up late (p = 0.005). The SLE-GI group also presented higher positivity rates for anti-SSA (69.6% vs. 45.7%, p = 0.020) and anti-SSB antibodies (32.6% vs. 10.9%, p = 0.011) but lower positivity rates for anti-dsDNA antibodies (30.4% vs. 82.6%, p < 0.001) compared with the SLE-LN group. CONCLUSION: The dietary patterns, life-styles and autoantibody spectrum of SLE-GI patients differed greatly from those of SLE-LN patients and healthy people. These factors may reflect the influence of disease and organ involvement modes on patients' daily life and may contribute partly to the systemic involvement in SLE.

Phenotype, function and clinical significance of innate lymphoid cells in immunoglobulin G4-related disease.

OBJECTIVES: The innate immune system participates in immunoglobulin G4-related disease (IgG4-RD). While the role of innate lymphoid cells (ILCs) in IgG4-RD remains to be elucidated, we aimed to evaluate the phenotype, function and clinical significance of ILCs in IgG4-RD patients. METHODS: Sixty-seven untreated IgG4-RD patients and 44 age- and sex-matched healthy controls (HCs) were enrolled. Circulating and tissue infiltration of ILCs were detected by flow cytometry. Serum suppression of tumorigenicity 2 (sST2) was detected by ELISA and membrane-bound ST2 (ST2L) was detected by flow cytometry. Tissue infiltration of IL-33 was measured by immunohistochemistry staining. Real-time quantitative PCR was performed to analyse the expression pattern of ILC2-associated genes between HCs and IgG4-RD patients. In addition, correlation analysis was performed in order to evaluate the clinical significance of ILCs in IgG4-RD. RESULTS: The frequency of circulating pan ILCs in IgG4-RD patients was lower than in HCs. ILC2s were higher in IgG4-RD compared with HCs, whereas ILC1s were lower in IgG4-RD. sST2 and ST2L were higher in IgG4-RD than in HCs. Infiltration of ILC1s in the submandibular glands of IgG4-RD patients was more prominent than ILC2s. Intracellular secretion of IL-9 was increased in ILC2s of IgG4-RD patients than in HCs. Circulating ILC2s correlated positively with Treg cells and the surface expression of CD154, PD-1 and CXCR5 in ILC2s correlated positively with CD19+ B cells, serum IgG4 levels and serum IgE, respectively. CONCLUSION: ILCs and their subsets were significantly altered in IgG4-RD. We demonstrated the dysfunction of ILC2s in IgG4-RD by phenotype, correlation analysis and function investigation, revealing ILC2s participated in the pathogenesis of IgG4-RD.

Novel autoantibodies identified in ACPA-negative rheumatoid arthritis.

OBJECTIVES: Lack of effective biomarkers in anti-citrullinated protein antibody (ACPA)-negative rheumatoid arthritis (RA) impedes early diagnosis and treatment. This study aimed to identify novel autoantibodies in RA and verify their diagnostic values in ACPA-negative RA based on protein microarray technology. METHODS: A total of 1011 sera from 559 RA (276 ACPA-positive and 283 ACPA-negative), 239 disease controls (DCs) and 213 healthy controls (HCs) were collected and sampled on two sequential microarrays and ELISA and western blot (WB) detection, for novel autoantibodies discovery, validation and verification, respectively. The high-density protein microarray printed with a broad spectrum of recombinant human proteins was first employed to screen candidate autoantibodies, then focused microarrays composed of candidate autoantigens were used for validation, followed by ELISA and WB to verify the presence of the most promising candidates in ACPA-negative RA. RESULTS: Nine novel autoantibodies were identified by two sequential microarrays with positivity 17.93%-27.59% and specificities >90% in ACPA-negative RA. Among these, anti-PTX3 and anti-DUSP11 autoantibodies presented with the highest sensitivity and were consistently verified by ELISA and WB. Pooling samples of all cohorts, the positivities of anti-PTX3 and anti-DUSP11 in ACPA-negative RA were 27.56% and 31.80%, respectively, similar to those in ACPA-positive RA, and significantly higher than in HCs (4.69% and 2.35%) and DCs (10.04% and 8.49%) (p<0.0001). Combination of anti-PTX3 with anti-DUSP11 significantly increased the diagnostic sensitivity (38.00%) with specificity of 88.72%, regardless of ACPA status. CONCLUSION: Anti-PTX3 and anti-DUSP11 autoantibodies are newly identified biomarkers for diagnosis of ACPA-negative RA.

Clinical manifestations and long-term prognosis of Good syndrome: Results from a single-center cohort study from China.

OBJECTIVE: To describe clinical features and long-term prognosis in patients with Good syndrome (GS). METHODS: We retrospectively reviewed medical records of GS patients at Peking Union Medical College Hospital from January 2001 to May 2019. Data regarding clinical manifestations and treatments were collected. Patients were routinely followed-up via clinical and telephone interviews, and survival analysis was performed with Kaplan-Meier analysis. RESULTS: Twenty-four patients were identified, including eight males and 16 females, with a median age at diagnosis of 58 years (interquartile range [IQR], 52-62 years). Twelve patients (50%) had autoimmune manifestations. Multi-organ involvements included musculoskeletal (37.5%), respiratory (33.3%), gastrointestinal (29.2%), hematologic (29.2%) systems, et.al. Infections were detected in 23 (95.8%) patients, mostly located in lung (69.6%), blood (26.1%), and gastrointestinal tract (21.7%). Thymectomy was performed in 23 patients, with the most common histology of type AB (10, 47.6%). Twenty-one patients were consecutively followed-up with a median follow-up of 84 (IQR, 48-116) months and 11 (52.4%) died, mainly due to infection (8/11, 72.7%). The 5- and 10-year survival rates were 90% (95% confidence interval [CI], 77.8-100%) and 38.5% (95% CI, 19.6-75.5%), respectively. CONCLUSION: GS patients tended to present with various infections and autoimmune manifestations. The 10-year survival rate from the Chinese population was poor, mainly due to infections.

Immune-related adverse events of checkpoint inhibitors: Insights into immunological dysregulation.

Immune checkpoint inhibitors (ICIs) targeting against programmed cell death-1(PD-1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) have shown efficacy in cancer treatment. However, a spectrum of immune-related adverse events (irAEs) have raised concerns about their clinical application. IrAEs are distinct from traditional chemo- and radiotherapy-induced toxicities, as they are related in particular to the dysregulation of immune system and autoimmunity. The underlying pathogenesis of irAEs remains elusive. Understanding of the potential underlying mechanism is of great importance for the management of irAEs and the development of new ICIs with insignificant irAEs. In this review, we summarize the current evidence to provide insights into the biological basis of irAEs and provide a potential explanation for their pathogenesis, with focus on the relationship between checkpoint molecules and immune cell regulation.

Are immune-related adverse events associated with the efficacy of immune checkpoint inhibitors in patients with cancer? A systematic review and meta-analysis.

BACKGROUND: A number of studies have reported an association between the occurrence of immune-related adverse events (irAEs) and clinical efficacy in patients undergoing treatment with immune checkpoint inhibitors (ICIs), but the results remain controversial. METHODS: Under the guidance of a predefined protocol and Preferred Reporting Items for Systematic Reviews and Meta-analyses statement, this meta-analysis included cohort studies investigating the association of irAEs and efficacy of ICIs in patients with cancer. The primary outcome was overall survival (OS), and the secondary outcome was progression-free survival (PFS). Subgroup analyses involving the cancer type, class of ICIs, combination therapy, sample size, model, landmark analysis, and approach used to extract the data were performed. Specific analyses of the type and grade of irAEs were also performed. RESULTS: This meta-analysis included 30 studies including 4971 individuals. Patients with cancer who developed irAEs experienced both an OS benefit and a PFS benefit from ICI therapy compared to patients who did not develop irAEs (OS: hazard ratio (HR), 0.54, 95% confidence interval (CI), 0.45-0.65; p < 0.001; PFS: HR, 0.52, 95% CI, 0.44-0.61, p < 0.001). Subgroup analyses of the study quality characteristics and cancer types recapitulated these findings. Specific analyses of endocrine irAEs (OS: HR, 0.52, 95% CI, 0.44-0.62, p < 0.001), dermatological irAEs (OS: HR, 0.45, 95% CI, 0.35-0.59, p < 0.001), and low-grade irAEs (OS: HR, 0.57, 95% CI, 0.43-0.75; p < 0.001) yielded similar results. The association between irAE development and a favorable benefit on survival was significant in patients with cancer who were undergoing treatment with programmed cell death-1 inhibitors (OS: HR, 0.51, 95% CI, 0.42-0.62; p < 0.001), but not cytotoxic T-lymphocyte antigen-4 inhibitors (OS: HR, 0.89, 95% CI, 0.49-1.61; p = 0.706). Additionally, the association was significant in patients with cancer who were treated with ICIs as a monotherapy (OS: HR, 0.53, 95% CI, 0.43-0.65; p < 0.001), but not as a combination therapy (OS: HR, 0.62, 95% CI, 0.36-1.05; p = 0.073). CONCLUSIONS: The occurrence of irAEs was significantly associated with a better ICI efficacy in patients with cancer, particularly endocrine, dermatological, and low-grade irAEs. Further large-scale prospective studies are warranted to validate our findings. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42019129310.

Antagonizing miR-7 suppresses B cell hyperresponsiveness and inhibits lupus development.

OBJECTIVES: The objective of this study was to address the biological function of miR-7 in an animal model of systemic lupus erythematosus. METHODS: MRLlpr/lpr lupus mice were administrated antagomiR-7 or a scramble control by tail vein for 5weeks. Three groups of animals' tissues were assessed for lupus manifestations by immunofluorescence and immunohistochemistry, and serum was examined for levels of autoantibodies and inflammatory cytokines. Splenic B cell subsets were assessed for intracellular expression of PI3K signaling by FACS. Finally, the ability of the miR-7 antagomir to regulate the expansion of T follicular helper (Tfh) cells and B cell hyperresponsiveness was further explored. RESULTS: We found that miR-7 was up-regulated in MRLlpr/lpr lupus mice and directly targeted PTEN mRNA in B cells. Up-regulated miR-7 in MRLlpr/lpr lupus B cells was negatively correlated with PTEN expression. Notably, miR-7 antagomir treatment reduced lupus manifestations in MRLlpr/lpr lupus mice. miR-7-mediated down-regulation of PTEN/AKT signaling promoted B cell differentiation into plasmablasts/plasma cells and spontaneous germinal center (GC) formation, whereas miR-7 antagomir normalized splenic B cell subtypes. Besides suppressing the activation of B cells, miR-7 antagomir intervention also down-regulated STAT3 phosphorylation and production of IL-21 and reduced Tfh expansion. CONCLUSION: The above data have demonstrated the critical roles of miR-7 not only in regulating PTEN expression and also B cell and Tfh cell function in lupus-prone MRLlpr/lpr lupus mice. Furthermore, the disease manifestations in MRLlpr/lpr lupus mice are efficiently improved by miR-7 antagomir, indicating miR-7 as a potential treatment strategy in SLE.

EZH2 deficiency attenuates Treg differentiation in rheumatoid arthritis.

The chromatin modifier enhancer of zeste homolog 2 (EZH2) methylates lysine 27 of histone H3 (H3K27) and regulates T cell differentiation. However, the potential role of EZH2 in the pathogenesis of rheumatoid arthritis (RA) remains elusive. We analyzed EZH2 expression in PBMC, CD4+ T cells, CD19+ B cell, and CD14+ monocytes from active treatment-naïve RA patients and healthy controls (HC). We also suppressed EZH2 expression using EZH2 inhibitor GSK126 and measured CD4+ T cell differentiation, proliferation and apoptosis. We further examined TGFß-SMAD and RUNX1 signaling pathways in EZH2-suppressed CD4+ T cells. Finally, we explored the regulation mechanism of EZH2 by RA synovial fluid and fibroblast-like synoviocyte (FLS) by neutralizing key proinflammatory cytokines. EZH2 expression is lower in PBMC and CD4+ T cells from RA patients than those from HC. EZH2 inhibition suppressed regulatory T cells (Tregs) differentiation and FOXP3 transcription, and downregulated RUNX1 and upregulated SMAD7 expression in CD4+ T cells. RA synovial fluid and fibroblast-like synoviocytes suppressed EZH2 expression in CD4+ T cells, which was partially neutralized by anti-IL17 antibody. Taken together, EZH2 in CD4+ T cells from RA patients was attenuated, which suppressed FOXP3 transcription through downregulating RUNX1 and upregulating SMAD7 in CD4+ T cells, and ultimately suppressed Tregs differentiation. IL17 in RA synovial fluid might promote downregulation of EZH2 in CD4+ T cells. Defective EZH2 in CD4+ T cells might contribute to Treg deficiency in RA.

Complement C1q synergizes with PTX3 in promoting NLRP3 inflammasome over-activation and pyroptosis in rheumatoid arthritis.

Excessive inflammatory cytokines play crucial roles in the pathogenesis of rheumatoid arthritis (RA), however, the underlying mechanism remains unclear. In this study, we demonstrated that pentaxin 3 (PTX3), an essential component of innate immunity, was elevated in RA and preferentially bound to CD14+ monocytes. C1q promoted the binding and resulted in increased cell proliferation, activation and caspase-1-related late apoptotic cells (7-AAD+annexin V+), as well as enhanced release of inflammatory cytokines including TNF-α, IL-1ß and IL-6. Serum from RA patients, compared with healthy controls, induced gasdermin D (GSDMD)-dependent pyroptosis in monocytes, and this ability was associated with disease activity. Moreover, PTX3 synergized with C1q to promote pyroptosis in RA-serum pre-incubated monocytes by coordinately enhancing NLRP3 inflammasome over-activation and inducing GSDMD cleavage, cell swelling with large bubbles, caspase-1-dependent cell death and inflammatory cytokine release including IL-6. On the other hand, IL-6 promoted PTX3 plus C1q-induced pyroptosis in both normal and RA serum pre-incubated monocytes. These findings collectively implicated an important role of IL-6 in driving PTX3 plus C1q-mediated pyroptosis in RA and shed lights on a potential new treatment strategy targeting pyroptosis-mediated persistent inflammatory cytokine release.

Comprehensive TCR repertoire analysis of CD4+ T-cell subsets in rheumatoid arthritis.

The pathogenesis of rheumatoid arthritis (RA), a systemic autoimmune disease characterized by autoreactive T-cell accumulation and pro-inflammatory cytokine overproduction, is unclear. Systematically addressing T-cell receptor (TCR) repertoires of different CD4+ T-cell subsets could help understand RA pathogenesis. Here, peripheral CD4+ T cells from treatment-naïve RA patients and healthy controls were sorted into seven subsets including naïve, effector, central memory, effector memory (EMT), Th1, Th17, and regulatory T cells. T-cell receptor ß chain repertoires were then analyzed by next-generation sequencing. We identified T-cell clonal expansion in EMT and Th17 cells of RA patients, with highly similar TCR repertoires. Ex vivo experiments demonstrated the preferred differentiation from EMT to Th17 cells in RA. Notably, we showed that TCR diversity and abundance of differentiated T cells of Th17 were significantly correlated with RA disease activity. Based on these observations, we propose that abnormal differentiation from EMT to Th17 and expansion of Th17 play pivotal role in RA pathogenesis.

Metagenomic profiling of the pro-inflammatory gut microbiota in ankylosing spondylitis.

OBJECTIVE: Gut dysbiosis has been reported implicated in ankylosing spondylitis (AS), a common chronic inflammatory disease mainly affects sacroiliac joints and spine. Utilizing deep sequencing on the feces of untreated AS patients, our study aimed at providing an in-depth understanding of AS gut microbiota. METHODS: We analyzed the fecal metagenome of 85 untreated AS patients and 62 healthy controls by metagenomic shotgun sequencing, and 23 post-treatment feces of those AS patients were collected for comparison. Comparative analyses among different cohorts including AS, rheumatoid arthritis and Behcet's disease were performed to uncover some common signatures related to inflammatory arthritis. Molecular mimicry of a microbial peptide was also demonstrated by ELISpot assay. RESULTS: We identified AS-enriched species including Bacteroides coprophilus, Parabacteroides distasonis, Eubacterium siraeum, Acidaminococcus fermentans and Prevotella copri. Pathway analysis revealed increased oxidative phosphorylation, lipopolysaccharide biosynthesis and glycosaminoglycan degradation in AS gut microbiota. Microbial signatures of AS gut selected by random forest model showed high distinguishing accuracy. Some common signatures related to autoimmunity, such as Bacteroides fragilis and type III secretion system (T3SS), were also found. Finally, in vitro experiments demonstrated an increased amount of IFN-γ producing cells triggered by a bacterial peptide of AS-enriched species, mimicking type II collagen. CONCLUSIONS: These findings collectively indicate that gut microbiota was perturbed in untreated AS patients with diagnostic potential, and some AS-enriched species might be triggers of autoimmunity by molecular mimicry. Additionally, different inflammatory arthritis shared some common microbial signatures.

Standardized patient methodology in mainland China: a nationwide survey.

BACKGROUND: To describe the current status of standardized patient (SP) practice in mainland China. METHODS: We conducted a nationwide survey in 2016. One hundred and eighty-three SP educators (SPEs) responded to the questionnaire, representing 80 medical centers from 25 provinces in mainland China. All of these centers were affiliated with China Standardized Patients Practice Teaching Guidance. In the survey, we assessed the methods of SPs' recruitment, hourly wage, how SPs were used and challenges of SP role. We also compared these data among the 4 different regions in China. RESULTS: In mainland China, the most frequent range of SPs' age was between 30 and 40 years (24.8%). The SPs were usually recruited by recommendations from the SPEs or a current SP (43.8%), as well as advertising in the hospitals (43.8%). The mean hourly wage was US$12.60 for teaching activities and US$18.82 for medical examinations. The median frequency for training SPs was 12.9 times per year. The SPs were used in areas such as internal medicine (89.6%), surgery (79.2%) and pediatrics (56.3%). The most challenging parts for the SPs were to remember all of the key points of the cases (51.9%) and portraying the emotions of the case (51.9%). Almost half of the SPs reported that, when interacting with medical students, they had difficulty in providing feedback in consistent with students' learning objectives. SPs' gender, age, rewards and scenarios playing were different significantly among the 4 geographic regions in China (P < 0.05). CONCLUSIONS: This survey provided the reliable data on the current situation of SP application in China. SP activities have had an encouraging progress but regional development imbalance.

Chemotaxis of Vδ2 T cells to the joints contributes to the pathogenesis of rheumatoid arthritis.

OBJECTIVES: To explore the role of Vδ2 T cells in the pathogenesis of rheumatoid arthritis (RA). METHODS: Sixty-eight patients with RA, 21 patients with osteoarthritis and 21 healthy controls were enrolled in the study. All patients with RA fulfilled the 2010 American College of Rheumatology/European League Against Rheumatism criteria for RA. Peripheral Vδ2T population, chemokine receptor expression and proinflammatory cytokine secretion were quantified by flow cytometry. The infiltration of Vδ2 T cells within the synovium was examined by immunohistochemistry and flow cytometry. The effect of tumour necrosis factor (TNF)-α and interleukin (IL)-6 on Vδ2 T migration was determined by flow cytometry and transwell migration assay. RESULTS: Peripheral Vδ2T cells, but not Vδ1 T cells, were significantly lower in patients with RA, which was negatively correlated with disease activity gauged by Disease Activity Score in 28 joints. Vδ2 T cells from RA accumulated in the synovium and produced high levels of proinflammatory cytokines including interferon-γ and IL-17. Phenotypically, Vδ2 T cells from RA showed elevated chemotaxis potential and expressed high levels of chemokine receptors CCR5 and CXCR3, which was driven by increased serum TNF-α through nuclear factor kappa B signalling. In vivo, TNF-α neutralising therapy dramatically downregulated CCR5 and CXCR3 on Vδ2 T cells and repopulated the peripheral Vδ2 T cells in patients with RA. CONCLUSIONS: High levels of TNF-α promoted CCR5 and CXCR3 expression in Vδ2 T cells from RA, which potentially infiltrated into the synovium and played crucial roles in the pathogenesis of RA. Targeting Vδ2 T cells might be a potential approach for RA.