Anti-TCP1 Antibody Is a Potential Biomarker for Diagnosing Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a chronic inflammatory disease caused by autoantibodies. Serum samples from patients with SLE (n = 10) were compared with those from normal controls (NCs, n = 5) using 21K protein chip analysis to identify a biomarker for SLE, revealing 63 SLE-specific autoantibodies. The anti-chaperonin-containing t-complex polypeptide-1 (TCP1) antibody exhibited higher expression in patients with SLE than in NCs. To validate the specificity of the anti-TCP1 antibody in SLE, dot blot analysis was conducted using sera from patients with SLE (n = 100), rheumatoid arthritis (RA; n = 25), Behçet's disease (BD; n = 28), and systemic sclerosis (SSc; n = 30) and NCs (n = 50). The results confirmed the detection of anti-TCP1 antibodies in 79 of 100 patients with SLE, with substantially elevated expression compared to both NCs and patients with other autoimmune diseases. We performed an enzyme-linked immunosorbent assay to determine the relative amounts of anti-TCP1 antibodies; markedly elevated anti-TCP1 antibody levels were detected in the sera of patients with SLE (50.1 ± 17.3 arbitrary unit (AU), n = 251) compared to those in NCs (33.9 ± 9.3 AU), RA (35 ± 8.7 AU), BD (37.5 ± 11.6 AU), and SSc (43 ± 11.9 AU). These data suggest that the anti-TCP1 antibody is a potential diagnostic biomarker for SLE.

Inhibition of Toll-like Receptors Alters Macrophage Cholesterol Efflux and Foam Cell Formation.

Arterial macrophage cholesterol accumulation and impaired cholesterol efflux lead to foam cell formation and the development of atherosclerosis. Modified lipoproteins interact with toll-like receptors (TLR), causing an increased inflammatory response and altered cholesterol homeostasis. We aimed to determine the effects of TLR antagonists on cholesterol efflux and foam cell formation in human macrophages. Stimulated monocytes were treated with TLR antagonists (MIP2), and the cholesterol efflux transporter expression and foam cell formation were analyzed. The administration of MIP2 attenuated the foam cell formation induced by lipopolysaccharides (LPS) and oxidized low-density lipoproteins (ox-LDL) in stimulated THP-1 cells (p < 0.001). The expression of ATP-binding cassette transporters A (ABCA)-1, ABCG-1, scavenger receptor (SR)-B1, liver X receptor (LXR)-α, and peroxisome proliferator-activated receptor (PPAR)-γ mRNA and proteins were increased (p < 0.001) following MIP2 administration. A concentration-dependent decrease in the phosphorylation of p65, p38, and JNK was also observed following MIP2 administration. Moreover, an inhibition of p65 phosphorylation enhanced the expression of ABCA1, ABCG1, SR-B1, and LXR-α. TLR inhibition promoted the cholesterol efflux pathway by increasing the expression of ABCA-1, ABCG-1, and SR-B1, thereby reducing foam cell formation. Our results suggest a potential role of the p65/NF-kB/LXR-α/ABCA1 axis in TLR-mediated cholesterol homeostasis.

Role of chemokines CXCL9, CXCL10, CXCL11, and CXCR3 in the serum and minor salivary gland tissues of patients with Sjögren's syndrome.

This study aimed to investigate the serum and expression levels of C-X-C motif chemokine ligand 9 (CXCL9), CXCL10, CXCL11, and CXC receptor 3 (CXCR3) in minor salivary glands (MSGs) of patients with primary Sjögren's syndrome (pSS), and to explore their correlations with clinical parameters. Serum samples from 49 patients diagnosed with pSS, 33 patients with rheumatoid arthritis (RA), and 30 healthy controls (HCs) were collected for measurements of CXCL9, CXCL10, CXCL11, and CXCR3. Additionally, CXCL levels in the MSG tissues were measured in 41 patients who underwent MSG biopsy. Correlations between CXCL and CXCL/CXCR levels in serum/MSG tissues and clinical factors/salivary scintigraphy parameters were analyzed. Serum CXCL11 and CXCR3 showed statistically significant differences among patients with pSS and RA and HCs (serum CXCL11, pSS:RA:HC = 235.6 ± 500.1 pg/mL:90.0 ± 200.3 pg/mL:45.9 ± 53.6 pg/mL; p = 0.041, serum CXCR3, pSS:RA:HC = 3.27 ± 1.32 ng/mL:3.29 ± 1.17 ng/mL:2.00 ± 1.12 ng/mL; p < 0.001). Serum CXCL10 showed a statistically significant difference between pSS (64.5 ± 54.2 pg/mL) and HCs (18.6 ± 18.1 pg/mL, p < 0.001), while serum CXCL9 did not exhibit a significant difference among the groups. Correlation analysis of clinical factors revealed that serum CXCL10 and CXCL11 levels positively correlated with erythrocyte sedimentation rate (r = 0.524, p < 0.001 and r = 0.707, p < 0.001, respectively), total protein (r = 0.375, p = 0.008 and r = 0.535, p < 0.001, respectively), globulin (r = 0.539, p < 0.001 and r = 0.639, p < 0.001, respectively), and European Alliance of Associations for Rheumatology SS Disease Activity Index (r = 0.305, p = 0.033 and r = 0.321, p = 0.025). Additionally, serum CXCL10 negatively correlated with the Schirmer test score (r = - 0.354, p = 0.05), while serum CXCL11 positively correlated with the biopsy focus score (r = 0.612, p = 0.02). In the MSG tissue, the percentage of infiltrating CXCL9-positive cells was highest (75.5%), followed by CXCL10 (29.1%) and CXCL11 (27.9%). In the correlation analysis, CXCL11-expressing cells were inversely related to the mean washout percentage on salivary gland scintigraphy (r = - 0.448, p = 0.007). Our study highlights distinct serum and tissue chemokine patterns in pSS, emphasizing CXCL9's potential for early diagnosis. This suggests that CXCL10 and CXCL11 are indicators of disease progression, warranting further investigation into their roles in autoimmune disorders beyond pSS.

Longitudinal assessment of urinary ALCAM, HPX, and PRDX6 in Korean patients with systemic lupus erythematosus: implications for disease activity monitoring and treatment response.

Introduction: This study aimed to demonstrate the potential of activated leukocyte cell adhesion molecule (ALCAM), hemopexin (HPX), and peroxiredoxin 6 (PRDX6) as urine biomarkers for systemic lupus erythematosus (SLE). Methods: Urine samples were collected from 138 Korean patients with SLE from the Ajou Lupus Cohort and 39 healthy controls (HC). The concentrations of urine biomarkers were analyzed using enzyme-linked immunosorbent assay kits specific for ALCAM, HPX, and PRDX6, respectively. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diagnostic utility, and Pearson's correlation analysis was conducted to assess the relationships between the disease activity and urine biomarkers. Results: Patients with SLE and patients with lupus nephritis (LN) showed significantly elevated ALCAM, HPX, and PRDX6 levels compared with HCs. ALCAM, HPX, and PRDX6 showed significant diagnostic values, especially for lupus nephritis (LN), with areas under the receiver operating characteristic curve for LN was 0.850 for ALCAM (95% CI, 0.778-0.921), 0.781 for HPX (95% CI, 0.695-0.867), and 0.714 for PRDX6 (95% CI, 0.617-0.812). Correlation analysis revealed that all proteins were significantly associated with anti-double stranded DNA antibody (ALCAM, r = 0.350, p < 0.001; HPX, r = 0.346, p < 0.001; PRDX6, r = 0.191, p = 0.026) and SLEDAI (ALCAM, r = 0.526, p < 0.001; HPX, r = 0.479, p < 0.001; PRDX6, r = 0.262, p = 0.002). Results from the follow-up of the three biomarker levels in these patients revealed a significant decrease, showing a positive correlation with changes in SLEDAI-2k scores (ALCAM, r = 0.502, p < 0.001; HPX, r = 0.475, p < 0.001; PRDX6, r = 0.245, p = 0.026), indicating their potential as indicators for tracking disease activity. Discussions: Urinary ALCAM, HPX, and PRDX6 levels have diagnostic value and reflect disease activity in Korean patients with SLE, emphasizing their potential for non-invasive monitoring and treatment response evaluation.

Uncovering risk factors for adverse events and infections in rheumatoid arthritis and rheumatoid arthritis with interstitial lung disease under treatment with biologics or targeted synthetic DMARDs: insights from the KOBIO Registry.

OBJECTIVES: This study aimed to identify the risk factors associated with overall adverse events (AEs) and infections in patients with rheumatoid arthritis (RA) and comorbid interstitial lung disease (ILD), receiving biologic or targeted synthetic disease-modifying anti-rheumatic drugs (b/tsDMARDs), using data from the Korean College of Rheumatology Biologics registry. METHODS: We analysed data from a cohort of 2,266 adult patients with RA who received b/tsDMARDs, including 169 patients with comorbid ILD. We identified the risk factors for overall AEs and infections in both the all RA group and the subgroup of patients with RA-ILD and investigated the impact of infections on mortality in patients with RA-ILD. RESULTS: Among all patients with RA, 45.7% withdrew b/tsDMARDs, whereas among those with RA-ILD, a higher proportion of 57.4% withdrew their treatment regimen. The main reason for withdrawing b/tsDMARDs in the RA-ILD group was AEs, with infections accounting for the largest proportion of reported AEs. In multivariable analysis of the risk factors for overall AEs and infections in the RA-ILD group, older age was identified as a risk factor for overall AEs (odds ratio [OR], 3.01; p=0.014), and only a current smoking status was identified as a risk factor for infections (OR, 2.11; p=0.035). CONCLUSIONS: Patients with RA-ILD exhibited a higher rate of b/tsDMARDs withdrawal due to overall AEs and infections than those with RA without ILD. In the RA-ILD group, older age was identified as a risk factor for overall AEs, whereas a current smoking status was identified as a risk factor for infections.

Patient preference, efficacy, and compliance with zoledronic acid for glucocorticoid-induced osteoporosis in patients with autoimmune diseases.

PURPOSE: We evaluated the preference, patient satisfaction, and efficacy of zoledronic acid compared with oral bisphosphonates (BPs) for glucocorticoid-induced osteoporosis (GIOP) in patients with autoimmune diseases. METHODS: We enrolled 50 patients with new fractures or osteoporosis detected on follow-up bone densitometry after at least 1 year of oral BP use among patients diagnosed with GIOP during treatment for autoimmune diseases. After 1 year of zoledronic acid treatment, patients completed a survey for preference and satisfaction assessment. Treatment efficacy was analysed by comparing bone mineral density changes and fractures with those in a control group of patients who continued oral BP use. RESULTS: Age, sex, treatment duration, and medication history did not differ significantly between the two groups. Among the participants, 86.7% preferred and were more satisfied with intravenous zoledronic acid than with oral BPs, primarily because of the convenience of its administration interval. Only two patients (4%) reported infusion-related adverse events with zoledronic acid. Furthermore, no significant differences were observed in the annualized percentage change in the bone mineral density of the lumbar spine, femur neck, and hip between patients receiving zoledronic acid and those receiving oral BPs. The occurrence of new fractures was consistent across both groups, with two cases in each, showing no significant differences. CONCLUSION: Patients showed a preference for and greater satisfaction with zoledronic acid, and its efficacy in treating osteoporosis was comparable to that of oral BPs. Therefore, zoledronic acid is a suitable treatment option for GIOP in patients with autoimmune diseases.

Clinical characteristics and prognostic factors of non-tuberculous mycobacterial disease in patients with rheumatoid arthritis.

BACKGROUND/AIMS: This study aimed to identify the clinical characteristics of patients with concurrent rheumatoid arthritis (RA) and suspected non-tuberculous mycobacterial (NTM) infections as well as determine their prognostic factors. METHODS: We retrospectively reviewed the medical records of 91 patients with RA whose computed tomography (CT) findings suggested NTM infection. Subsequently, we compared the clinical characteristics between patients with and without clinical or radiological exacerbation of NTM-pulmonary disease (PD) and investigated the risk factors for the exacerbation and associated mortality. RESULTS: The mean age of patients with RA and suspected NTM-PD was 65.0 ± 10.2 years. The nodular/bronchiectatic (NB) form of NTM-PD was the predominant radiographic feature (78.0%). During follow-up, 36 patients (41.9%) experienced a radiological or clinical exacerbation of NTM-PD, whereas 12 patients (13.2%) died. Combined interstitial lung disease (ILD), microbiologically confirmed NTM-PD, and NB with the fibrocavitary (FC) form on chest CT were identified as risk factors for the clinical or radiological exacerbation of NTM-PD. Hydroxychloroquine use was identified as a good prognostic factor. Conversely, history of tuberculosis, ILD, smoking, microbiologically confirmed NTM-PD, and NB with the FC form on chest CT were identified as poor prognostic factors for mortality in suspected NTM-PD. CONCLUSION: ILD and NB with the FC form on chest CT were associated with NTM-PD exacerbation and mortality. Hydroxychloroquine use may lower the risk of NTM-PD exacerbation. Therefore, radiographic features and presence of ILD should be considered when predicting the prognosis of patients with RA and suspected NTM-PD.

Efficacy and safety of intravenous belimumab in a subgroup of South Korean patients with systemic lupus erythematosus enrolled into a Phase 3, randomized, placebo-controlled trial in North East Asia.

AIM: This post hoc analysis evaluated the efficacy and safety of intravenous belimumab 10 mg/kg in the South Korean subgroup of patients with systemic lupus erythematosus (SLE) enrolled in the North East Asia (NEA) study (GSK Study BEL113750; NCT01345253). METHODS: NEA was a double-blind, placebo-controlled, randomized Phase 3 trial. Patients with active, autoantibody-positive SLE were randomized 2:1 to belimumab or placebo plus standard therapy administered on Days 0, 14, and 28, and then every 28 days up to Week 48. The primary efficacy endpoint in this analysis was SLE Responder Index 4 (SRI-4) response rate at Week 52, defined as the proportion of patients achieving a ≥4-point reduction in Safety of Estrogens in Lupus Erythematosus National Assessment-SLE Disease Activity Index (SELENA-SLEDAI) score, no worsening (<0.3 increase from baseline) in Physician Global Assessment, no new British Isles Lupus Assessment Group (BILAG) A domain and <2 new BILAG B domain scores. RESULTS: Among 100 South Korean patients enrolled in NEA, 54/66 (81.8%) belimumab- and 24/34 (70.6%) placebo-treated patients completed the double-blind phase. Significantly more belimumab- than placebo-treated patients achieved SRI-4 response at Week 52 (n = 35/66, 53.0% vs. n = 8/34, 23.5%; odds ratio [OR; 95% confidence interval (CI)]: 3.67 [1.45, 9.28]; p = .0061). The proportion of patients experiencing ≥1 adverse event was similar between groups (belimumab: n = 60/66, 90.9% vs. placebo: n = 31/34, 91.2%). No new safety signals emerged in this subgroup analysis. CONCLUSION: Belimumab was efficacious for the treatment of SLE and well tolerated among the South Korean subgroup of patients from the NEA study.

Seasonal vitamin D levels and lupus low disease activity state in systemic lupus erythematosus.

BACKGROUND: Seasonal variation and sunlight exposure can impact serum vitamin D levels, potentially influencing lupus symptoms. We investigated seasonal vitamin D levels and their correlation with clinical manifestations and disease activity in systemic lupus erythematosus (SLE). METHODS: Serum 25(OH) vitamin D3 (25(OH)D3) levels were categorised as deficient (25(OH)D3 < 10 ng/mL), insufficient (10-30 ng/mL) and sufficiency (>30 ng/mL) in participants analysed in winter (n = 407) and summer (n = 377). Logistic regression analysis was performed to assess the impact of vitamin D levels on achieving a lupus low disease activity state (LLDAS), stratified by season. RESULTS: The mean serum 25(OH)D3 levels differed significantly between the winter and summer measurement groups (22.4 vs. 24.2 ng/mL; p = .018). The prevalences of vitamin D deficiency, insufficiency and sufficiency in the winter group were 12.8%, 66.6% and 20.6%, respectively, compared with 4.5%, 67.9% and 27.6% in the summer group. Achieving LLDAS was highest in the vitamin D sufficiency group (winter: 56.6%, summer: 55%) and lowest in the vitamin D deficiency group (winter: 15.4%, summer: 13.6%), with significant differences (all p < .001). Multivariate analysis identified SLE disease activity index ≤4, normal anti-double-stranded DNA and vitamin D sufficiency as significant factors for achieving LLDAS in both seasons. CONCLUSIONS: Sufficient vitamin D levels are important for achieving LLDAS in patients with SLE during winter and summer. Therefore, physicians should pay attention to the adequacy of vitamin D levels and consider recommending vitamin D supplementation for patients with vitamin D insufficiency.

Biosimilars in the treatment of rheumatoid arthritis: a pharmacokinetic overview.

INTRODUCTION: As of May 2023, 19 and 18 biosimilars have been approved for the treatment of rheumatoid arthritis (RA) by the European Medicines Agency (EMA) and United States Food and Drug Administration (US FDA) respectively. AREA COVERED: Pharmacokinetic results of phase 1 studies of approved biosimilars were reviewed by systematic literature search. The impact of immunogenicity on the pharmacokinetic data and clinical response was assessed, and the potential benefit of monitoring serum concentrations of biologic drugs is discussed. The advantage of subcutaneous CT-P13 (an infliximab biosimilar) in clinical practice is reviewed. EXPERT OPINION: Biosimilars are approved based on the totality of evidence including comparable physiochemical properties, PK / PD profiles, and clinical efficacy and safety to the originator. To utilize biosimilars more effectively, physicians should be aware of the utility of combination DMARD therapy to reduce immunogenicity and maintain efficacy and PK profile. PK monitoring, however, is not currently recommended in clinical practice. CT-P13 subcutaneous (SC) is the first SC infliximab used for treatment of RA patients. Based on data from clinical studies and the real world, SC-infliximab is an attractive therapeutic option compared to IV formulations of infliximab based on its efficacy, pharmacokinetics, patient-reported outcomes, and safety profile.

Unveiling difficult-to-treat rheumatoid arthritis: long-term impact of biologic or targeted synthetic DMARDs from the KOBIO registry.

BACKGROUND: While the availability of biological or targeted synthetic disease-modifying anti-rheumatic drugs (b/tsDMARDs) has improved outcomes for rheumatoid arthritis (RA) patients, there remains a subset of individuals who fail to achieve low disease activity or remission despite multiple cycles of b/tsDMARDs. This state is referred to as 'difficult-to-treat (D2T)' RA. METHODS: Data from the Korean College of Rheumatology Biologics registry were utilized to analyze patients with RA who were treated with b/tsDMARDs. RESULTS: Among 2,321 RA patients with RA treated with b/tsDMARDs, 271 (11.7%) were diagnosed with D2T RA. Lower age (OR = 0.98, p < 0.001), longer disease duration (OR = 1.06, p < 0.001), lower patient global assessment (OR = 0.89, p = 0.045), higher SDAI (OR = 1.06, p = 0.014) and RAPID3 (OR = 1.06, p = 0.002), lower RF positivity (OR = 0.65, p = 0.04), and lower prior use of methotrexate (OR = 0.44, p = 0.008), sulfasalazine (OR = 0.59, p = 0.003), and leflunomide (OR = 0.67, p = 0.013) were associated with D2T RA. The drug survival rate of b/tsDMARDs did not differ between patients with D2T RA and non-D2T RA (p = 0.35). However, the drug survival of individual b/tsDMARD differed between patients with D2T RA and non-D2T RA after eight years. Patients with D2T RA withdrew from b/tsDMARDs due to inefficacy more frequently than those without D2T RA (p < 0.001). CONCLUSIONS: D2T RA patients experienced higher disease activity despite maintaining b/tsDMARD therapy. Withdrawal rates due to inefficacy were higher in D2T RA. Effective therapeutic strategies are needed to improve disease control and treatment outcomes in this unique patient population.

Effects of COVID-19 and Influenza Vaccination on Rheumatic Diseases: Results From a Survey of Patient-Reported Outcomes After Vaccination.

BACKGROUND: This study aimed to compare the occurrence of adverse events (AEs) and disease flares after vaccination against coronavirus disease 2019 (COVID-19) and influenza in patients with autoimmune rheumatic diseases (ARDs). METHODS: Between November 2021 and March 2022, a survey was conducted among patients with ARD who received COVID-19 and influenza vaccinations. The questionnaire included 11 mandatory and closed-ended questions, and the following items were collected: medical history, immunization history, type of vaccine, patient-reported AEs, flare-up of the underlying disease after vaccination, and a confirmed diagnosis of COVID-19 or influenza. We compared the occurrence of vaccine-related adverse reactions to the COVID-19 and influenza vaccines based on the survey results. Multivariate logistic regression analysis was used to identify the factors affecting AEs or disease flares and to compare the post-vaccine response to mixed and matched vaccines. RESULTS: We analyzed 601 adults with ARD who received the COVID-19 vaccine, with a mean age of 49.6 years (80.5% female). A total of 255 participants (42.4%) received a complete course of primary vaccination, 342 (56.9%) completed the booster dose, and 132 (38.6%) received a mixed vaccine. The frequencies of AEs (188 [52.2%] vs. 21 [5.8%]; P < 0.001) and disease flares (58 [16.2%] vs. 5 [1.4%]; P < 0.001) after COVID-19 vaccination were significantly higher than those after influenza vaccination. In the risk factor analysis, previous allergic reaction to other vaccines (odds ratio, 1.95; confidence interval, 1.07-3.70; P = 0.034) was the only factor associated with the occurrence of AEs. There was no difference in the post-vaccine responses between the mixed and matched vaccines. CONCLUSION: The results of the survey of patients with ARD revealed that patient-reported AEs and underlying disease flares after receiving the COVID-19 vaccine were significantly higher than those after the influenza vaccine.

Rosuvastatin treatment alone cannot alleviate lupus in murine model: a pilot study.

Objective: Systemic lupus erythematosus (SLE) is an autoimmune disease, characterized by the production of autoantibodies and high cholesterol levels. HMG-CoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase inhibitors have exhibited anti-inflammatory effects in several clinical trials. We conducted this study to evaluate the effect of rosuvastatin on inflammatory responses in lupus-prone mice. Methods: MRL/lpr mice were intraperitoneally injected with rosuvastatin (10 mg/kg, n=4) or vehicle (2% dimethyl sulfoxide, n=4) five times a week from 13 to 17 weeks of age. The serum levels of low-density lipoprotein (LDL) cholesterol and autoantibodies were measured, as well as the urine levels of albumin. Renal tissues were stained for histopathological analysis. Concentrations of key inflammatory cytokines were measured in the serum, and messenger RNA (mRNA) levels in target organs (kidney, spleen, and lymph nodes) were evaluated. Results: Rosuvastatin treatment significantly decreased serum LDL cholesterol concentration in MRL/lpr mice. However, the clinical manifestations and autoantibody titres did not improve with rosuvastatin treatment. In addition, serum inflammatory cytokines and proteinuria did not change. Histopathological analysis of the kidneys revealed no improvement. When assessing the expression of mRNA, treatment with rosuvastatin decreased tumor necrosis alpha and interleukin-17 concentration in spleen and kidney tissue and in the kidneys and lymph nodes of MRL/lpr mice, respectively. Conclusion: Although it can decrease inflammatory cytokines in the lymphoid organs and kidneys of MRL/lpr mice, treatment with rosuvastatin is insufficient to alleviate SLE.

Association between CCR2 and CCL2 expression and NET stimulation in adult-onset Still's disease.

Adult-onset Still's disease (AOSD) is a systemic inflammatory disease characterized by the activation of monocyte-derived cells and the release of neutrophil extracellular traps (NET). C-C motif ligand (CCL) 2 is a chemoattractant that interacts with the C-C motif chemokine receptor (CCR) 2, resulting in monocyte recruitment and activation. CCL2 and CCR2 were measured with enzyme-linked immunosorbent assay (ELISA) at the serum level, and using immunohistochemical staining at the skin and lymph node tissues levels. THP-1 cell lysates were analyzed using western blot and ELISA after NET stimulation in patients with AOSD. Serum CCL2 level was higher in patients with AOSD than in patients with rheumatoid arthritis and healthy controls (HCs). In patients with AOSD, the percentage of CCL2-positive inflammatory cells in the skin tissues and CCR2-positive inflammatory cells in the lymph nodes increased, compared to that in HCs and in patients with reactive lymphadenopathy, respectively. NET induced in patients with AOSD enhanced the secretion of CCR2, higher CCR2 expression in monocytes, and the levels of interleukin (IL)-1ß, IL-6, and IL-18 from THP-1 cells. Our findings suggest that upregulation of the CCL2-CCR2 axis may contribute to the clinical and inflammatory characteristics of AOSD.

Increased Immunoglobulin Gamma-3 Chain C in the Serum, Saliva, and Urine of Patients with Systemic Lupus Erythematosus.

Immunoglobulin gamma-3 chain C (IGHG3) levels have been detected in the blood and tissue of patients with systemic lupus erythematosus (SLE). This study aims to assess its clinical value by measuring and comparing levels of IGHG3 in different body fluids in patients with SLE. The levels of IGHG3 in saliva, serum, and urine from 181 patients with SLE and 99 healthy controls were measured and analyzed. In patients with SLE and healthy controls, salivary IGHG3 levels were 3078.9 ± 2473.8 and 1413.6 ± 1075.3 ng/mL, serum IGHG3 levels were 478.1 ± 160.9 and 364.4 ± 97.9 µg/mL, and urine IGHG3 levels were 64.0 ± 74.5 and 27.1 ± 16.2 ng/mL, respectively (all p < 0.001). Salivary IGHG3 was correlated with ESR (correlation coefficient [r], 0.173; p = 0.024). Serum IGHG3 was correlated with leukocyte count (r, -0.219; p = 0.003), lymphocyte count (r, 0.22; p = 0.03), anti-dsDNA antibody positivity (r, 0.22; p = 0.003), and C3 levels (r, -0.23; p = 0.002). Urinary IGHG3 was correlated with hemoglobin level (r, -0.183; p = 0.021), ESR (r, 0.204; p = 0.01), anti-dsDNA antibody positivity (r, 0.262; p = 0.001), C3 levels (r, -0.202; p = 0.011), and SLE disease activity index (r, 0.332; p = 0.01). Urinary IGHG3 was higher in patients with nephritis than in those without (119.5 ± 110.0 vs. 49.8 ± 54.4 ng/mL; p < 0.01). IGHG3 was increased in the saliva, serum, and urine of patients with SLE. While salivary IGHG3 was not identified to be specific to SLE disease activity, serum IGHG3 showed correlations with clinical characteristics. Urinary IGHG3 levels were associated with disease activity and renal involvement in SLE.

The transcription factor Mef2d regulates B:T synapse-dependent GC-TFH differentiation and IL-21-mediated humoral immunity.

Communication between CD4 T cells and cognate B cells is key for the former to fully mature into germinal center-T follicular helper (GC-TFH) cells and for the latter to mount a CD4 T cell-dependent humoral immune response. Although this interaction occurs in a B:T synapse-dependent manner, how CD4 T cells transcriptionally regulate B:T synapse formation remains largely unknown. Here, we report that Mef2d, an isoform of the myocyte enhancer factor 2 (Mef2) transcription factor family, is a critical regulator of this process. In CD4 T cells, Mef2d negatively regulates expression of Sh2d1a, which encodes SLAM-associated protein (SAP), a critical regulator of B:T synapses. We found that Mef2d regulates Sh2d1a expression via DNA binding-dependent transcriptional repression, inhibiting SAP-dependent B:T synapse formation and preventing antigen-specific CD4 T cells from differentiating into GC-TFH cells. Mef2d also impeded IL-21 production by CD4 T cells, an important B cell help signaling molecule, via direct repression of the Il21 gene. In contrast, CD4 T cell-specific disruption of Mef2d led to a substantial increase in GC-TFH differentiation in response to protein immunization, concurrent with enhanced SAP expression. MEF2D mRNA expression inversely correlates with human systemic lupus erythematosus (SLE) patient autoimmune parameters, including circulating TFH-like cell frequencies, autoantibodies, and SLEDAI scores. These findings highlight Mef2d as a pivotal rheostat in CD4 T cells for controlling GC formation and antibody production by B cells.

Retention Rate and Safety of Biologic and Targeted Synthetic DMARDs in Patients with RA-Associated Interstitial Lung Disease: A KOBIO Registry Study.

OBJECTIVES: This study aimed to evaluate the long-term retention and safety of biologic disease-modifying antirheumatic drugs (bDMARDs) and targeted synthetic DMARDs (tsDMARDs) and identify the factors associated with drug withdrawal in patients with rheumatoid arthritis (RA) with interstitial lung disease (ILD) enrolled in the Korean College of Rheumatology Biologics and Targeted Therapy registry. METHODS: We investigated adults with RA (n = 2266) administered with bDMARDs or tsDMARDs between 2012 and 2021. Propensity score matching (1:3) was performed between patients with RA with ILD (RA-ILD) and without ILD (RA-no ILD). The Kaplan-Meier method was used to analyse drug survival and a logistic regression model to identify withdrawal-related factors in RA-ILD. RESULTS: One hundred and fifty-nine patients with RA-ILD were matched with 477 patients with RA-no ILD. The 5-year drug retention rate was lower in RA-ILD than in RA-no ILD (log-rank p = 0.020), and both the ILD and no-ILD groups had statistical differences of drug retention rate among agents (log-rank p = 0.019 and 0.020, respectively). In the RA-ILD group, Janus kinase inhibitors had the highest drug retention rate (64.3%), and tumour necrosis factor-α inhibitors showed the lowest retention rate (30.6%). Approximately 58.5% and 48.4% of the patients with RA-ILD and RA-no ILD, respectively, withdrew from their regimen, and the main cause of withdrawal in RA-ILD was adverse events, followed by inefficacy. In the logistic regression analysis, current smoking had a negative effect on drug retention (odds ratio [OR]: 9.938, 95% confidence interval [CI]: 2.550-38.733; p < 0.001), while concomitant corticosteroid use had a protective effect against withdrawal (OR: 0.284, 95% CI: 0.008-0.917; p = 0.035) in RA-ILD. CONCLUSION: The patients with RA-ILD had lower bDMARD and tsDMARD retention rates than those with RA-no ILD. In the RA-ILD group, current smoking and concomitant corticosteroid use were associated factors affecting drug withdrawal.

Safety and Effectiveness of Etanercept Biosimilar SB4 for Rheumatic Diseases in South Korea: Real-World Post-marketing Surveillance Data.

INTRODUCTION: SB4 is the first approved biosimilar of etanercept, a biologic tumor necrosis factor inhibitor, to treat various autoimmune diseases including axial spondylarthritis (axSpA), rheumatoid arthritis (RA), psoriatic arthritis (PsA), and plaque psoriasis (PsO). This post-marketing surveillance (PMS) study of SB4 investigated safety and effectiveness in routine clinical practice and is part of the drug approval process in Korea. METHODS: This prospective, multi-center, open-label, observational, phase IV PMS study was designed to enroll patients with axSpA, RA, PsA, and PsO in Korea from September 2015 to September 2019. Both etanercept-naïve patients or patients switched from reference etanercept were included. SB4 was administered weekly via subcutaneous injections using pre-filled syringes. Safety was assessed by the incidence of adverse events (AEs), adverse drug reactions (ADRs) and serious adverse events (SAE). Effectiveness was assessed by the change from baseline of investigator-rated Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) in patients with ankylosing spondylitis (AS) and disease activity score-28 (DAS28) in patients with RA. RESULTS: Among 316 enrolled patients, 314 were included in the safety analysis (176 with AS and 138 with RA). The overall incidence of AEs, ADRs and serious AEs were 17.8, 9.9, and 1.3%, respectively. Most AEs were mild (66.7%) or moderate (31.1%) and not related to SB4 (58.9%). Most common AEs were injection site pruritus (1.9%) and injection site rash (1.3%). At week 24, mean disease activity scores significantly decreased compared to baseline in naïve patients with AS and RA (BASDAI 2.7 vs. 6.2, p < 0.0001; DAS28 3.8 vs. 5.7, p < 0.0001) and in switched patients with AS and RA (BASDAI 1.0 vs. 1.3, p = 0.0018; DAS28 2.4 vs. 2.9, p = 0.0893). CONCLUSION: This first real-world evidence of SB4 from a phase IV PMS study in Korea shows comparable effectiveness to historical SB4 real-world evidence without any new significant safety signals.

Efficacy and drug retention of tofacitinib in rheumatoid arthritis: from the nationwide Korean College of Rheumatology Biologics registry.

OBJECTIVES: Janus kinase inhibitors are expected to change the management patterns and prognosis of chronic rheumatic diseases. This study aimed to evaluate the efficacy, drug retention, and adverse events of tofacitinib, a Janus kinase inhibitor, for rheumatoid arthritis (RA) using a Korean nationwide database. METHODS: Data of patients with RA receiving tofacitinib were extracted from the Korean College of Rheumatology Biologics and Targeted Therapy registry, including clinical characteristics and disease activity markers for RA. Outcomes of clinical efficacy, drug survival rate, and safety profiles were compared between biologic disease-modifying anti-rheumatic drug (bDMARD)-naive and -failure patients. Mann-Whitney U-test, logistic regression analysis, Kaplan-Meier analysis, and log-rank test were used in data analysis. RESULTS: Three hundred patients with RA received tofacitinib therapy (16.3% male; mean age 55.4±11.9 years); 91 patients were bDMARD-naive. Baseline disease activity markers and proportions of patients who were taking conventional synthetic DMARDs were not different between bDMARD-naive and bDMARD-failure patients. American College of Rheumatology responses and disease activity score-28 did not differ between bDMARD-failure and -naive patients at the 1-year follow-up. The drug retention rate of tofacitinib did not differ between bDMARD-failure (155 per 2.4 years) and -naive patients (89 per 1.9 years) (log-rank test, p=0.202). In logistic regression, the positivity of RF and ACPA were associated with reduced drug retention (p=0.01 and 0.02, respectively). Totally 83 (27.7%) of patients had adverse, and 14 (4.7%) patients had herpes zoster infection. CONCLUSIONS: Nationwide real-world data showed that tofacitinib therapy is effective in patients with RA independent of previous use of a bDMARD. The drug retention of tofacitinib did not differ between bDMARD-failure and -naive patients, and RF or ACPA positivity may be associated with reduced discontinuation of tofacitinib.