The newly discovered Treg subset (CLA+ Tregs) expressing cutaneous lymphocyte-associated antigen is associated with inflammatory conditions. This study elucidated the role of CLA+ Tregs in rheumatoid arthritis (RA) development and its responses to treatment. A total of 12 T cell subsets, together with total T cells, B cells, and NK cells were analyzed in 169 patients with RA and 114 healthy controls using flow cytometry. Autoantibodies were detected by ELISA. The logistic regression models were employed to assess the association between cell subsets and rheumatoid arthritis. Relationships between CLA+ Tregs and clinical variables were assessed. Among the immune cell subsets analyzed, CLA⁺ Tregs were the most significantly reduced ones in patients with RA compared with healthy controls (OR 0.825 [0.764–0.891], p < 0.001). Decreased CLA⁺ Tregs were strongly correlated to active disease status (adjusted OR 0.814 [0.733–0.902], p = 0.004; AUC 0.916 [0.869–0.963], p < 0.001). Decreased CLA+ Tregs were associated with higher swollen joint count, tender joint count and DAS28 scores, as well as systemic involvements, including interstitial lung disease (ILD), anemia, fever, and skin vasculitis. Additionally, rheumatoid factor (RF) and anti-mutated citrullinated vimentin antibody (anti-MCV) were correlated to lower CLA+ Tregs. Compared to baseline prior treatment, CLA+ Tregs increased significantly in RA patients, accompanied by improvements in disease activity (median, 9.60

Behçet’s syndrome (BS), a chronic vasculitis, leads to recurrent oral ulcers, severely impacting quality of life. Here we report the results of a randomized, double-blind, placebo-controlled trial (NCT04065672) to evaluate the efficacy and safety of low-dose interleukin-2 (LD-IL-2) in BS patients. 60 participants with active oral ulcers are randomly assigned to receive LD-IL-2 or placebo. The primary endpoint is the oral ulcer count at week 12. The LD-IL-2 group has significantly fewer oral ulcers than the placebo group (0.69 ± 1.05 vs. 1.57 ± 0.90, P = 0.001) with greater improvements in ulcer pain, disease activity, and quality of life. No infections or severe adverse events are observed in either group. LD-IL-2 expands regulatory T (Treg) cells and decreased the ratio of effector T cell to Treg cells. Thus, LD-IL-2 therapy might be an effective and safe treatment in BS patients and is associated with the modulation of CD4 + T cell populations. Behçet’s syndrome is a chronic inflammatory disease with oral ulcers being the most common symptom. Here authors present results from a phase 2 randomized double-blind placebo-controlled clinical trial that shows that systemic low dose interleukin-2 could be safely administered to these patients, and the therapy may improve their quality of life.

Objective This study explored the relationship between clinical phenotypes and immuno-molecular features of systemic lupus erythematosus (SLE) using unsupervised machine learning and multi-omics integration.Methods A multicentre cohort of 1065 SLE patients from five teaching hospitals was studied. Unsupervised clustering was performed using integrated clinical and laboratory data to identify distinct phenotypic clusters. Multi-omics profiling, including proteomics and transcriptomics, was conducted for each cluster, comparing with healthy controls. In addition, 899 patients were prospectively followed for over 1 year to assess therapeutic responses and remission outcomes.Results Unsupervised clustering identified five distinct clusters of SLE based on clinical phenotypes and immunological signatures, and an intrinsic association was found between each cluster and immune-inflammatory features. Cluster 1 (renal; 14.27%) had predominant renal involvement (87.5%) and high disease activity. Cluster 2 (mucocutaneous; 39.53%) exhibited mainly cutaneous manifestations (72.45%) with mild visceral involvement and the highest rates of achieving low disease activity state (46.42%). Cluster 3 (neuropsychiatric; 14.74%) had a high frequency of neuropsychiatric manifestations (96.18%) and anti-U1 ribonucleoprotein antibodies positivity (42.04%). Cluster 4 (haematologic; 22.63%) was characterised by haematologic involvement, predominantly cytopenia (95.85%), with frequent antiphospholipid antibody positivity and direct Coombs positivity (87.55%). Cluster 5 (cardiopulmonary; 8.83%) exhibited prominent cardiopulmonary involvement (97.87%) and serositis, with enrichment of inflammatory CD161+ regulatory T cells. Transcriptomic and proteomic analyses confirmed distinct molecular signatures and cluster-specific enrichment of biological pathways. Key molecule apolipoprotein A4 was validated using enzyme-linked immunosorbent assay. Regarding therapeutic outcomes at 1 year follow-up, Cluster 2 had the highest proportions achieving lupus low disease activity state (46.42%) and tapering glucocorticoids. Cyclophosphamide use was associated with greater clinical improvement (r=0.284; p=0.023) in Cluster 3, while in Cluster 5, rituximab use was associated with favourable responses (r=0.286; p=0.019).Conclusions We identified five SLE clusters with distinct clinical, immunological features and treatment outcomes, demonstrating an intrinsic link between clinical involvement and immune-inflammatory alterations.

This study aimed to evaluate the efficacy and safety of upadacitinib in patients with refractory Behcet’s syndrome (BS). A multicentre, single-arm trial was conducted from February 2023 to August 2025. Eligible patients had BS refractory to at least two immunosuppressive agents or one targeted therapy for a minimum of 6 months. Participants discontinued previous targeted therapies and received upadacitinib 15 mg/day for up to 48 weeks, in addition to their ongoing glucocorticoid and immunosuppressant regimens. Clinical features, inflammatory markers, imaging findings, and treatment data were collected throughout follow-up. The primary endpoint was the overall response rate (ORR; complete response [CR] plus partial response [PR]) at 24 weeks. Twenty-seven patients (16 male; median age 36 years) were enrolled, with a median baseline BDCAF score of 4 (range: 2–7). Affected systems included the mucocutaneous, articular, gastrointestinal, cardiovascular, and ocular systems. The ORR at 24 weeks was 85.2

OBJECTIVES:Insulin resistance (IR) is frequently observed and associated with complications of cardiovascular disease among the RA population. Triglyceride-glucose (TyG)-related indexes, serving as surrogates for assessing IR, have been significantly associated with mortality in some chronic diseases. However, their prognostic roles in the RA population have not been validated to date. METHODS:A cohort of 764 RA participants, spanning from 1999 to 2018, was recruited from the National Health and Nutrition Examination Survey (NHANES). Kaplan-Meier (KM) curves, restricted cubic splines (RCS), and the Cox proportional hazards model were used to analyse the relationship between TyG-related indexes and mortality. RESULTS:During a median follow-up of 82 months, 235 all-cause and 73 cardiovascular deaths were recorded. The survival rates for the higher TyG and TyG-WHtR groups were significantly lower compared with those in the lower group. Multivariate Cox proportional hazards analysis showed that higher TyG was significantly associated with all-cause mortality (HR = 1.60, P = 0.011) and cardiovascular mortality (HR = 2.36, P = 0.017). The RCS curves showed a significant non-linear trend between cardiovascular mortality and TyG-WHtR, TyG-WC, TyG-BMI (P for non-linearity < 0.05), with inflection points at 6.11, 869.84 and 314.01, respectively. Interaction analysis revealed significant effect modification by BMI, drinking, race and education (P for interaction < 0.05). The sensitivity analyses supported the positive associations between TyG-related indexes and mortality in the RA population. CONCLUSIONS:This study highlights the prognostic value of TyG-related indicators with thresholds for predicting mortality, which suggests that TyG-related surrogates could be effective biomarkers for risk stratification in clinical management among the RA population.

This study aimed to use machine learning to explore Behçet’s syndrome (BS) heterogeneity by integrating immunocyte subpopulations and clinical characteristics. We prospectively enrolled BS patients and recorded their demographic and clinical characteristics. Various peripheral immune cells were analysed using flow cytometry. Unsupervised machine learning was used to perform cluster analysis based on the clinical manifestations and immune cell subsets. Patients were followed up for one year to evaluate treatment response and remission rates. RNA sequencing was performed in patients with clustered BS and healthy controls. Unsupervised machine learning categorized 201 BS patients into four clusters with distinct clinical and immunological features. Cluster 1 showed isolated mucocutaneous lesions, low inflammation, and high remission, with transcriptomic enrichment in IFN-γ, IL-6, and JAK-STAT pathways. Cluster 2 featured arthritis, elevated inflammatory levels, and responded well to TNF-α inhibitors, with transcriptomic enrichment in TNF and B-cell activation pathways. Cluster 3 had cardiovascular involvement, reduced CLA+ Tregs, and also responded to TNF-α inhibitors, with transcriptomic enrichment in coagulation, platelet activation, and MAPK pathways. Cluster 4 demonstrated neurological involvement, elevated CD161⁺ Tregs, low remission, and a better response to mycophenolate mofetil, with transcriptomic enrichment in T-cell activation and NF-κB pathways. Unsupervised clustering of BS patients revealed four distinct subtypes with significant clinical and immunological heterogeneity, which may provide a foundation for mechanistic studies and personalized treatment.

Objective Behçet syndrome (BS) is a systemic autoimmune vasculitis characterized by immune dysregulation involving multiple immune cell subsets. CD161+ Treg cells exhibit proinflammatory properties and impair immune regulation during inflammation. This study aimed to investigate the alterations in CD161+ Treg cells in BS and their clinical relevance, particularly in disease pathogenesis and neurologic involvement. Methods This prospective multicenter study included 182 patients diagnosed with BS at the three hospitals between 2018 and 2024, 166 patients with systemic lupus erythematosus (SLE) and 149 patients with rheumatoid arthritis (RA) and 114 patients with healthy controls (HCs). Demographic and clinical data were recorded. CD4+CD25highCD127lowCD161+ T cells (CD161+ Treg cells) in peripheral blood were analyzed via flow cytometry. Statistical analysis included the Wilcoxon rank‐sum test, Fisher's exact test, and logistic regression, with P < 0.05 considered significant. Results Patients with BS had a significantly higher proportion among total Treg cells and CD4+ T cells, as well as higher absolute number of CD161+ Treg cells compared to HCs. CD161+ Treg cell levels negatively correlated with Foxp3+ Treg cells and positively correlated with Teff cells. Patients with BS had higher absolute number of CD161+ Treg cells than that in patients with SLE and in patients with RA. Moreover, patients with BS with higher erythrocyte sedimentation rate or C‐reactive protein or with neurologic involvement exhibited higher CD161+ Treg cells, which were identified as a risk factor for neurologic involvement. Among 41 patients with BS observed after treatment, CD161+ Treg cells significantly decreased, correlating with reduced disease activity. Conclusion Patients with BS exhibit an increased CD161+ Treg cells in peripheral blood, which may contribute to immune dysregulation and neurologic involvement. The reduction of CD161+ Treg cells following treatment suggests their potential role as a biomarker for disease activity in BS.

OBJECTIVE:This study aimed to assess the efficacy and safety of baricitinib in Takayasu arteritis (TAK) refractory to TNF-α inhibitors. METHODS:We conducted a multicentre, single-arm trial between February 2021 and August 2023. Patients with TAK unresponsive to at least 6 months of TNF-α inhibitors were treated with baricitinib 4 mg daily for up to 48 weeks, while continuing of immunosuppressants and glucocorticoids. Clinical features, inflammatory parameters, imaging changes and treatment data were collected during follow-up. The primary end point was the overall response (ORR) (complete response [CR] plus partial response [PR]) at 24 weeks. RESULTS:A total of 10 patients (nine female and one male) patients were enrolled, with median age of 29 years (26.0, 35.3) and a median disease duration of 56.5 months (31.8, 88.5). The ORR at 24 weeks was 80%, with six patients achieving CR and two achieving PR. Disease progression was noted in the remaining two patients. Disease activity, ESR and CRP at 24 weeks were significantly decreased compared with those at baseline. The median glucocorticoid dosage decreased from 20.0 mg/day (15.0, 26.3) at baseline (P < 0.001) to 6.3 mg/day (4.4, 10.6) at 24 weeks. No relapse was observed in the eight patients who achieved a response. The adverse effects (AEs) included upper respiratory tract infection (n = 2) and diarrhoea (n = 1), with no serious AEs reported. CONCLUSION:Baricitinib is effective in patients with TAK resistant to conventional treatments and anti-TNF-α therapy and demonstrates a notable steroid-sparing effect. TRIAL REGISTRATION:ClinicalTrials.gov; NCT06662721.

BACKGROUND:Breast cancer is a common tumor in women, which significantly impacts their health and quality of life. The incidence of breast cancer has been increasing globally. OBJECTIVE:This study aimed to investigate the preferences of Chinese women regarding breast cancer screening (BCS) during the COVID-19 pandemic and examine how these preferences influence their screening choices. METHOD:The online DCE (Discrete Choice Experiment) questionnaire was designed through Sawtooth Lighthouse Studio (9.8.1) with the following selected attributes: acceptable hospital distances, acceptable hospital grades, duration of each screening, main screening method, total acceptable length of screening, and total cost of screening. Data were analyzed with a mixed logistic analysis after the data collection was completed. A latent class analysis was also performed to observe the screening preferences of participants, their willingness to pay, and to infer whether the distribution of preferences between the different parties was statistically significant. RESULTS:A total of 397 people filled out the questionnaire, and 325 people met the inclusion criteria after being screened by trap questions. Each attribute is important in shaping participants' preferences for BCS provision. People preferred "Ultrasound Screening," "No side effects," higher medical reimbursement rates, and lower costs. CONCLUSION:These findings provide valuable insights into the thoughts and preferences of participants regarding BCS. Healthcare providers should take these preferences into consideration to improve patient compliance and enhance the effectiveness and safety of clinical care.

Low-dose interleukin 2 (Ld-IL2) is increasingly being explored as an immune-modulating treatment for autoimmune diseases which mainly affect T cell subsets. This study investigates the metabolic effects of Ld-IL2 therapy in patients with primary Sjögren’s syndrome (pSS). A total of 60 patients were recruited to conduct a double-blind, randomized clinical trial. Of these patients, 50

Behcet's syndrome (BS) is a vasculitis characterized by immune dysregulation. Biomarkers are valuable for assessing clinically atypical pathogenesis. We aimed to investigate the distribution of different biomarkers and their effects on the clinical features of patients with BS in a large-scale, real-world study. This is a retrospective, single-center study. In total, 502 patients diagnosed with BS were enrolled in this study. We analyzed the clinical features of this cohort and divided patients’ symptoms into six categories, including mucocutaneous, articular, neurological, gastrointestinal, vascular, and ocular involvements. HLA-B51 cells, autoantibodies, and subsets of immune cells from the patients were tested. Pearson’s correlation, Wilcoxon rank sum test and multivariate logistic regression were used for data analysis. Various autoantibodies were detected in the serum of 40.8

OBJECTIVE:To investigate the correlation factors of complete clinical response in idiopathic inflammatory myopathies (IIMs) patients receiving conventional treatment.METHODS:Patients diagnosed with IIMs hospitalized in Peking University People's Hospital from January 2000 to June 2023 were included. The correlation factors of complete clinical response to conventional treatment were identified by analyzing the clinical characteristics, laboratory features, peripheral blood lymphocytes, immunological indicators, and therapeutic drugs.RESULTS:Among the 635 patients included, 518 patients finished the follow-up, with an average time of 36.8 months. The total complete clinical response rate of IIMs was 50.0% (259/518). The complete clinical response rate of dermatomyositis (DM), anti-synthetase syndrome (ASS) and immune-mediated necrotizing myopathy (IMNM) were 53.5%, 48.9% and 39.0%, respectively. Fever (P=0.002) and rapid progressive interstitial lung disease (RP-ILD) (P=0.014) were observed much more frequently in non-complete clinical response group than in complete clinical response group. The aspartate transaminase (AST), lactate dehydrogenase (LDH), D-dimer, erythrocyte sedimentation rate (ESR), C-reaction protein (CRP) and serum ferritin were significantly higher in non-complete clinical response group as compared with complete clinical response group. As for the treatment, the percentage of glucocorticoid received and intravenous immunoglobin (IVIG) were significantly higher in non-complete clinical response group than in complete clinical response group. Risk factor analysis showed that IMNM subtype (P=0.007), interstitial lung disease (ILD) (P=0.001), eleva-ted AST (P=0.012), elevated serum ferritin (P=0.016) and decreased count of CD4+T cells in peripheral blood (P=0.004) might be the risk factors for IIMs non-complete clinical response.CONCLUSION:The total complete clinical response rate of IIMs is low, especially for IMNM subtype. More effective intervention should be administered to patients with ILD, elevated AST, elevated serum ferritin or decreased count of CD4+T cells at disease onset.

The founding family member, Interleukin (IL)-17A, is commonly known as IL-17 and has garnered increasingly attention for proinflammatory functions in autoimmune disorders. Although the effects of IL-17A on hepatic important drug-metabolizing enzymes and transporters (DMETs) expression still remain unclear, it is critical to ascertain owing to the well-established alterations of the drug disposition capacity of the liver occurring during immune imbalance. The present study was designed to explore the effects and mechanisms of IL-17A on DMETs mRNA and protein expression in HepaRG cells by real-time quantitative reverse transcription polymerase chain reaction and Western blot, respectively. It is discovered that IL-17A can inhibit most DMETs mRNA expression (drug-metabolizing enzymes of CYP1A2, CYP3A4, CYP2C9, CYP2C19, GSTA1 and UGT1A1 and transporters of NTCP, OCT1, OATP1B1, BCRP and MDR1) as well as the protein expression of CYP3A4 and CYP2C19, via the janus kinase 2 (JAK2)-signal transducer and activator of transcription 3 (STAT3) signaling pathway. Thus, abnormal regulation of DMETs in IL-17A-mediated immune disorders such as psoriasis may cause alterations in pharmacokinetic processes and may occasionally result in unexpected drug-drug interactions (DDIs) in clinical practice.

Objective: This study aims to describe patients' characteristics and treatment responses with primary Sjo & BULL;gren's syndrome (pSS) who experience immune thrombocytopenia (ITP) and ITP with clinical significance (ITPCS). Methods: A retrospective study was conducted involving 164 patients diagnosed with pSS-related ITP after excluding secondary ITP. Patients were categorized into subgroups based on the risk of bleeding: major bleeding event (MBG), non-hemorrhagic group (NHG), and hematological involvement-only SS group (HOSG). Results: 57 (34.8%) were diagnosed with ITP simultaneously with pSS, while 60 (36.6%) were diagnosed with ITP before pSS. ITP patients exhibited a high prevalence of interstitial lung disease (19.5%), and an up to 96.3% positive presence of anti-SSA/Ro-52 antibody. ITPCS was identified in 58.5% of patients, with 22.0% experiencing high-risk hemorrhagic events. A median (range) of 2 (1, 3) treatment lines for maintenance therapies were administered. Corticosteroids and hydroxychloroquine (HCQ) led to an ITP response in 76.1% of patients. Ciclosporin A (CsA) and other medicines contributed to a 76.6% response. The MBG, NHG, and HOSG groups consisted of 36 (22.0%), 68 (41.5%) and 53 (32.3%) patients, respectively. Notably, patients of MBG were more frequently diagnosed before SS onset (p = 0.035). They required more treatment lines (p = 0.001) with a lower risk of relapse (p < 0.001), which is confirmed in patients with only hematological involvement (HOSG group). Conclusion: Patients with pSS-related ITP face an increased risk of bleeding, particularly in the MBG group, which necessitates more extensive treatment. Heterogeneous treatment regimens were observed for pSS-related ITP, and combinations involving corticosteroids, HCQ, and/or CsA appear viable options.

Learning points for cliniciansProgressive pseudorheumatoid (PPD) arthritis is a rare autosomal recessive genetic disorder resulting from mutations in the Wnt-1 inducible signaling pathway protein-3 (WISP3) gene.The disease is characterized by non-inflammatory polyarthropathy, degeneration of joints, metaphyseal dysplasia of limbs and platyspondyly.Here, we present a Chinese PPD patient with a novel WISP3 mutation.

Background::Existing evidence suggests that fruit consumption is a significant influencing factor for chronic obstructive pulmonary disease (COPD), but this is unclear in the Chinese population. We examined the association of fresh fruit consumption with the risk of COPD-related hospitalization and death in a nationwide, population-based prospective cohort from China.Methods::Between 2004 and 2008, the China Kadoorie Biobank recruited >0.5 million adults aged 30 to 79 years from ten diverse regions across China. After excluding individuals diagnosed with major chronic diseases and prevalent COPD, the prospective analysis included 421,428 participants. Cox regression was used to calculate the hazard ratios (HRs) for the association between fresh fruit consumption and risk of COPD-related hospitalization and death, with adjustment for established and potential confounders.Results::During a mean follow-up of 10.9 years, 11,292 COPD hospitalization events and deaths were documented, with an overall incidence rate of 2.47/1000 person-years. Participants who consumed fresh fruit daily had a 22% lower risk of COPD-related hospitalization and death compared with non-consumers (HR= 0.78, 95% confidence interval [CI]: 0.71–0.87). The inverse association between fresh fruit consumption and COPD-related hospitalization and death was stronger among non-current smokers and participants with normal body mass index (BMI) (18.5 kg/m 2 ≤ BMI < 24.0 kg/m 2); the corresponding HRs for daily fresh fruit consumption were 0.78 (95% CI: 0.68–0.89) and 0.69 (95% CI: 0.59–0.79) compared with their counterparts, respectively. Conclusions::High-frequency fruit consumption was associated with a lower risk of COPD in Chinese adults. Increasing fruit consumption, together with cigarette cessation and weight control, should be considered in the prevention and management of COPD.

Objective: Human epididymis protein 4 (HE4) can differentiate interstitial lung disease from patients with some rheumatic diseases. However, the clinical utility of HE4 in idiopathic inflammatory myopathies (IIM) remains unclear.Methods: 80 IIM patients and 91 age and gender-matched healthy controls (HCs) were recruited. Clinical and laboratory data were recorded at baseline and 12 weeks. HE4 was tested by the method of electrochemical luminescence.Results: Compared to HCs, the levels of HE4 significantly elevated in IIM patients. Patients with elevated HE4 had a higher interstitial lung disease (ILD) prevalence. Among patients with ILD, histological patterns of organizing pneumonia had higher HE4 levels than non-specific interstitial pneumonia. Further, there was a positive cor-relation between HE4 and the semi-quantitative CT grade (r = 0.778, p < 0.001) and a negative relation between HE4 and the percentage of forced vital capacity (p < 0.001) and diffusing capacity of the lung for carbon monoxide (DLco) (p = 0.001). An optimal cut-off value of HE4 (79.6 pmol/L) for distinguishing IIM-ILD was analyzed by ROC analysis with an AUC of 0.733 (p = 0.002). Regression analysis revealed that elevated HE4 independently identified IIM-related ILD (OR 34.8, 95 %CI, 3.58-338.14, p = 0.002). With the improvement after treatment, serum HE4 levels were significantly decreased (p = 0.006), accompanied by improved DLco% (p = 0.012).Conclusions: Serum HE4 was significantly elevated in patients with IIM and may be utilized as a serum biomarker to evaluate the disease severity and prognosis of IIM-related ILD.

Primary Sjögren syndrome (pSS) is a systemic autoimmue disease featured by excessive autoantibody production. It has been demonstrated that anti-carbonic anhydrase II (anti-CA II) antibody is correlated with renal tubular acidosis in pSS; however, no further details about urinary acidification defect have been reported, and the antibody's relationship with other organ impairments remains unknown. This case-control study aimed to examine anti-CA II antibody levels in relation to various systemic complications in pSS, and evaluate its potential role as a organ-specific biomarker in a Chinese cohort. Serum anti-CA II antibody levels were determined using ELISA in 123 patients with pSS and 72 healthy controls. The medical records of the patients were collected, and the correlation between serum anti-CA II antibody and clinical/immunological parameters was investigated. Serum anti-CA II antibody level and its positive rate were significantly increased in pSS patients compared with controls, and ANA-positive patients presented even higher titers of the antibody. In anti-CA II positive group, remarkably higher urine pH and bicarbonate, as well as lower urine titratable acid and serum potassium were observed, which indicated renal tubular acidification dysfunction both involving bicarbonate reabsorption and acid secretion. In addition, platelet count and complement 3, complement 4 levels decreased, whereas serum IgG, IgA and γ-globulin levels increased notably in accord with a higher EULAR SS disease activity index score in these patients. Further analysis showed that anti-CA II antibody was most elevated in patients with defect in bicarbonate reabsorption, reflecting proximal renal tubular injury, rather than in patients with distal renal tubular acidosis as previously reported. In conclusion, anti-CA II antibody reflects renal (especially proximal renal tubular) and hematologic impairment as well as increased disease activity in pSS. It may act as a serum biomarker of systemic damage of pSS.

OBJECTIVE:To investigate the significance of anti-histidyl tRNA synthetase (Jo-1) antibody in idiopathic inflammatory myopathies (IIM) and its diseases spectrum.METHODS:We enrolled all the patients who were tested positive for anti-Jo-1 antibody by immunoblotting in Peking University People's Hospital between 2016 and 2022. And the patients diagnosed with anti-synthetase antibody syndrome (ASS) with negative serum anti-Jo-1 antibody were enrolled as controls. We analyzed the basic information, clinical characteristics, and various inflammatory and immunological indicators of the patients at the onset of illness.RESULTS:A total of 165 patients with positive anti-Jo-1 antibody were enrolled in this study. Among them, 80.5% were diagnosed with connective tissue disease. And 57.6% (95/165) were diagnosed with IIM, including ASS (84/165, 50.9%), immune-mediated necrotizing myopathy (7/165, 4.2%) and dermatomyositis (4/165, 2.4%). There were 23.0% (38/165) diagnosed with other connective tissue disease, mainly including rheumatoid arthritis (11/165, 6.7%), undifferentiated connective tissue disease (5/165, 3.0%), interstitial pneumonia with autoimmune features (5/165, 3.0%), undifferentiated arthritis (4/165, 2.4%), Sjögren's syndrome (3/165, 1.8%), systemic lupus erythematosus (3/165, 1.8%), systemic vasculitis (3/165, 1.8%), and so on. Other cases included 3 (1.8%) malignant tumor patients, 4 (2.4%) infectious cases and so on. The diagnoses were not clear in 9.1% (15 /165) of the cohort. In the analysis of ASS subgroups, the group with positive serum anti-Jo-1 antibody had a younger age of onset than those with negative serum anti-Jo-1 antibody (49.9 years vs. 55.0 years, P=0.026). Clinical manifestations of arthritis (60.7% vs. 33.3%, P=0.002) and myalgia (47.1% vs. 22.2%, P=0.004) were more common in the ASS patients with positive anti-Jo-1 antibody. With the increase of anti-Jo-1 antibody titer, the incidence of the manifestations of arthritis, mechanic hands, Gottron sign and Raynaud phenomenon increased, and the proportion of abnormal creatine kinase and α-hydroxybutyric dehydrogenase index increased in the ASS patients. The incidence of myalgia and myasthenia were significantly more common in this cohort when anti-Jo-1 antibody-positive ASS patients were positive for one and more myositis specific antibodies/myositis associated autoantibodies (P < 0.05).CONCLUSION:The disease spectrum in patients with positive serum anti-Jo-1 antibody includes a variety of diseases, mainly ASS. And anti-Jo-1 antibody can also be found in many connective tissue diseases, malignant tumor, infection and so on.