The agreement between ultrasound-determined joint inflammation and clinical signs in patients with rheumatoid arthritis

Joint-level responses to tofacitinib and methotrexate: a post hoc analysis of data from ORAL Start

BACKGROUND

Rheumatoid arthritis (RA) has a variable impact on different synovial joints, with inflammation being more commonly observed in some joints than others. Emerging evidence suggests that the anatomical variation in pathophysiology could result in differential responses to treatments across the joints, both within and between modes of action. This analysis aimed to characterize joint-specific responses to tofacitinib and methotrexate monotherapy in patients with RA.

METHODS

This was a post hoc analysis of data from the phase III trial ORAL Start (NCT01039688), in methotrexate-naïve patients with RA. A paired joint pathology score (PJPS), derived from bilateral tender/swollen joint counts, was calculated. The percentage change from baseline in PJPS (%∆PJPS) and treatment-specific responses (tofacitinib 5 and 10 mg twice daily [BID] vs methotrexate; tofacitinib 5 vs 10 mg BID) for each patient joint pair, except for those with baseline/post-baseline PJPS = 0, were calculated at month 3, month 6, and month 12. Radiographic progression was similarly assessed using the Modified Total Sharp Score at month 6 and month 12.

RESULTS

In methotrexate-naïve patients, differences in %∆PJPS demonstrated greater responses with tofacitinib vs methotrexate in most joint locations. Lesser responses with tofacitinib vs methotrexate were observed in most joints of the feet, particularly at month 12. Despite this, radiographic progression at month 12 was significantly worse in the foot (and metacarpophalangeal) joints of patients receiving methotrexate vs tofacitinib.

CONCLUSION

We observed variation in joint-specific responses with tofacitinib and methotrexate monotherapy. Despite a proximal-distal efficacy gradient, with better clinical responses in the feet, patients receiving methotrexate monotherapy demonstrated more radiographic progression in the foot joints compared with those receiving tofacitinib. These findings suggest that body site- and therapy-specific characteristics may interact to produce differential treatment responses.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01039688.

Patterns of Involvement of the Hand Joints in Classical Rheumatoid Arthritis

BACKGROUND

Symmetrical involvement of the hand joints is described as characteristic of rheumatoid arthritis (RA). Quantitative data on specific patterns of involvement are lacking.

OBJECTIVE

The Brigham Rheumatoid Arthritis Sequential Study was created for observational studies of patients with RA and afforded a unique opportunity to answer these questions.

METHODS

Of 1598 subjects in the Brigham Rheumatoid Arthritis Sequential Study cohort, 535 met the following criteria: (1) disease duration of 7 years or greater, (2) seropositive, and (3) hand radiographs available. Patterns in specific hand joints based on physical examination and radiographic findings obtained at entry were identified. The level of symmetry of involvement of the metacarpophalangeal (MCP) and wrist joints was determined, as was the correlation between findings on physical examination and radiographic changes in the hand joints.

RESULTS

The prevalence of joint space narrowing and/or erosions in each proximal interphalangeal (PIP) joints ranged between 11% and 18%. Joint space narrowing and/or erosions in the MCPs increased radially from the fifth to the second finger. Swelling and tenderness on physical examination of both the PIPs and MCPs also increased radially although the positive predictive value of physical examination as an indicator of joint damage decreased radially. The wrist was the most common joint involved both by physical examination (67%) and radiographically (70%). The right side was more involved radiographically. Analysis of radiographic changes in individual patients revealed that symmetrical findings in the wrists and MCPs occurred in only 67% of patients.

CONCLUSIONS

The study describes the pattern of involvement of the hand joints in patients with long standing RA. Findings of interest include symmetrical involvement in only 67% of patients and a discordancy between physical findings and radiographic changes most marked in the more radial PIP joints.

Expression of Nrf2 protein in serum of patients with rheumatoid arthritis: A novel indicator for disease activity and disease prognosis

OBJECTIVE

This study aimed to detect the expression level of nuclear factor erythroid 2-related factor 2 (Nrf2) in the serum of patients with rheumatoid arthritis (RA) to clarify the correlation between Nrf2 levels and medical parameters, such as disease activity, pro-inflammatory factor, clinical characteristics, as well as changes after treatment.

METHODS

Serum samples were collected from 100 patients with RA and 42 normal controls (NCs). Serum levels of Nrf2 protein, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-17A, and malondialdehyde (MDA) were analyzed. The receiver operating characteristic (ROC) curve was adopted to assess the potential of Nrf2 to predict different levels of disease activity in patients with RA. The relationship between clinical variables and parameters were evaluated.

RESULTS

For the first time, it was reported that Nrf2 levels were significantly elevated in the serum of patients with RA compared to those of NCs, as were the MDA levels. The levels of Nrf2 were positively correlated with the disease activity and pro-inflammatory factor levels. The significant cut-off points for Nrf2 to determine RA disease activity were 0.69 ng/mL, 0.69 ng/mL and 1.18 ng/mL. Levels of Nrf2 were higher in RA patients with wrist joint involvement and interstitial lung disease. Moreover, Nrf2 levels decreased after treatment.

CONCLUSIONS

Serum Nrf2 protein level is potentially a novel indicator to monitor disease activity and prognosis in patients with RA.

Seeing is believing: Smart use of musculoskeletal ultrasound in rheumatology practice

Musculoskeletal ultrasonography has become an increasingly valuable tool as a complement to the physical exam in rheumatology practice. Its point-of-care access, low cost, safety, portability, and reliability in trained hands, make this technique especially useful in patients with inflammatory arthritis. Growing evidence has demonstrated the value of musculoskeletal ultrasound in the detection of inflammatory and structural changes in patients with joint pain without obvious joint swelling, in differentiating various inflammatory diagnoses, in the monitoring of inflammatory arthritis, and interventional procedures. The potential role of ultrasound guiding treat-to-target strategies or tapering treatment in inflammatory arthritis requires further research. However, musculoskeletal ultrasound can also have pitfalls and limitations that a clinician should be aware of.

The correlation of ultrasound-detected synovitis in an individual small joint with overall clinical disease activity in patients with rheumatoid arthritis

OBJECTIVES

To explore the correlation between the ultrasound-detected synovitis in each individual joint at metacarpophalangeal (MCP), proximal interphalangeal (PIP), and metatarsophalangeal (MTP) regions and the clinical disease activity in patients with rheumatoid arthritis (RA).

METHODS

Clinical disease activity was assessed by disease activity score (DAS) based on 28-joint count and erythrocyte sedimentation rate (DAS28-ESR), C-reactive protein (DAS28-CRP), Simplified Disease Activity Index (SDAI), and Clinical Disease Activity Index (CDAI). Gray scale (GS) and power Doppler (PD) synovitis was assessed by ultrasound semi-quantitatively. The correlation between clinical disease activity indices and synovitis score in each joint was assessed using Spearman's rank correlation test.

RESULTS

211 RA patients were included in this study. The whole GS scores of all MCP joints showed the highest correlation with each Clinical Disease Activity Index (r = 0.403-0.452, p < 0.01). Likewise, the whole PD scores of all MCP joints also showed the highest correlation with clinical disease activity (r = 0.332-0.396, p < 0.01). At individual joint level, the highest correlation of GS score with DAS28-ESR (r = 0.411, p < 0.01), DAS28-CRP (r = 0.459, p < 0.01), and SDAI (r = 0.444, p < 0.01) was observed in MCP3 joint while with CDAI (r = 0.421, p < 0.01) in MCP2 joint. The highest correlation of PD score with DAS28-ESR (r = 0.353, p < 0.01), DAS28-CRP (r = 0.399, p < 0.01), CDAI (r = 0.368, p < 0.01), and SDAI (r = 0.377, p < 0.01) was observed in MCP5 joint.

CONCLUSIONS

The ultrasound-detected synovitis at MCP joints, especially MCP2, MCP3, and MCP5 joints, was best correlated with clinical disease activity in most RA cases, in contrast to PIP and MTP joints. Key Points • The correlation of ultrasound-detected synovitis in each individual joint with the clinical disease activity in RA patients is diverse among joint regions. MCP joints showed the best, in contrast to PIP and MTP joints.

Does tenosynovitis of the hand detected by B-mode ultrasound predict loss of clinical remission in rheumatoid arthritis? Results from a real-life cohort

Objective

The role of US-detected tenosynovitis (USTS) in the management of rheumatoid arthritis remains controversial. The aim of this study was to investigate whether tenosynovitis can predict a flare in rheumatoid arthritis patients in remission in a real-life cohort.

Methods

Rheumatoid arthritis patients from the Swiss Clinical Quality Management cohort were included in this study if they were in clinical remission, defined by 28-joint disease activity score (DAS28-ESR) <2.6, and had an available B-mode tenosynovitis score. The patients were stratified according to the presence or absence of tenosynovitis (USTS+ vs. USTS–). Cox proportional hazard models were used for time-to-event analysis until the loss of remission, after adjustment for multiple confounders. The impact of baseline US performed early in remission and the advent of flares at different fixed time periods after baseline were investigated in sensitivity analysis.

Results

Tenosynovitis was detected in 10% of 402 rheumatoid arthritis patients in remission. At baseline, USTS+ patients in remission had significantly higher DAS28-ESR (mean (SD): USTS– 1.8 (0.5) versus USTS+ 2.0 (0.5); p = 0.0019) and higher additional disease activity parameters, such as physician global assessment, and simplified- and clinical-disease activity index. Joint synovitis detected by B-mode US was associated with tenosynovitis (mean (SD) 7.2 (6.3) in USTS– versus 9.0 (5.4) in USTS+, respectively; p = 0.02). A disease flare was observed in 69% of remission phases, with no differences in the time to loss of remission between USTS+ and USTS– groups.

Conclusion

While US-detected tenosynovitis was associated with higher disease activity parameters in rheumatoid arthritis patients in clinical remission, it was not able to predict a flare.

Identification of poor prognostic joint locations in an early rheumatoid arthritis cohort at risk of rapidly progressing disease: a post-hoc analysis of the Phase III AGREE study

Background

Rheumatoid arthritis (RA) is a heterogeneous disease with established poor prognostic factors such as seropositivity, joint damage, and high disease activity at an early, treatment-naïve stage of disease. However, few studies have examined if specific joint locations are correlated with these factors in such a population. This analysis explored the potential correlation of individual swollen and erosive joints with other disease characteristics at baseline and with remission rates in a post-hoc analysis of the Phase III randomized AGREE study.

Methods

Methotrexate (MTX)-naïve, erosive, RF- and/or ACPA-positive early RA patients (N = 509) were retrospectively evaluated. Baseline joint swelling was analyzed for large and small joints. Baseline erosions were analyzed for wrist, MCP1–5, IP1, PIP2–5 and MTP1–5. Remission rates were assessed after 6 months of treatment with abatacept (ABA) + MTX (N = 256) or MTX (N = 253). The following statistical tests were used: Chi-Square or Fisher’s exact test (categorical variables); Student’s t-test or Wilcoxon rank-sum test (continuous variables); continuity-corrected Chi-square test (efficacy remission endpoints).

Results

Baseline swelling was most frequent in wrist (91.9%) and MCP2 joint (89.1%), while baseline erosion was most frequent in MTP5 joint (43.5%). Swollen shoulder was significantly correlated (p < 0.0001) with swelling of almost all other large or medium joints. Baseline swelling in the knee, temporomandibular joint (TMJ), wrist and elbow was highly correlated (p < 0.001) with higher tender and swollen joint counts, higher DAS28(CRP) and higher SDAI and CDAI. Baseline swelling was not correlated with erosion per joint, except for MCP2. The largest difference in mean Boolean remission rates at 6 months was in patients with baseline swollen wrist favoring ABA + MTX (14.0% vs 4.4%; p < 0.001).

Conclusions

Swelling in the large and medium joints (knee, TMJ, elbow and wrist) was highly correlated with severe disease activity while MCP2 swelling seemed to be correlated with joint damage. The correlation of joint locations at an early, treatment-naïve stage with poor prognostic factors, higher disease activity and joint damage, could establish a rapidly progressing anatomical pattern in early RA.

Trial registration: ClinicalTrials.gov NCT00122382, registered July 2005.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41927-022-00252-4.

A Four-miRNA-Based Diagnostic Signature for Rheumatoid Arthritis

Background

As a chronic inflammatory disease, rheumatoid arthritis (RA) usually leads to cartilage and bone damage, even disability. Earlier detection and diagnosis are crucial to improve the therapeutic efficacy, and the aim of our study is to identify a potential diagnostic signature for RA.

Methods

We downloaded the GSE124373 dataset from the Gene Expression Omnibus (GEO) database. And differential expression analysis of miRNAs was conducted using the limma package of R language. The potential targeted mRNAs of differentially expressed miRNAs were predicted using the MiRTarBase database. The clusterProfiler package in R language was used to conduct functional enrichment analysis (GO term and KEGG pathway). Then, based on the key miRNAs screened by stepwise regression analysis, the logistic regression model was built and it was evaluated using a 5-fold cross-validation method.

Results

A total of 19 differentially expressed miRNAs in the blood sample of RA patients compared with that of healthy subjects were identified. Nine optimal miRNAs were screened by using stepwise regression analysis, and four key miRNAs hsa-miR-142-5p, hsa-miR-1184, hsa-miR-1246, and hsa-miR-99b-5p were further optimized. Finally, a logistic regression model was built based on the four key miRNAs, which could reliably separate RA patients from healthy subjects.

Conclusion

Our study established a logistic regression diagnostic model based on four crucial miRNAs, which could separate the sample type reliably.

Diagnostic value of semi-quantitative grading of musculoskeletal ultrasound in wrist and hand lesions of subclinical synovitis in rheumatoid arthritis

We used semi-quantitative grading of musculoskeletal ultrasound to evaluate wrist and hand lesions of subclinical synovitis, in order to make earlier diagnosis of rheumatoid arthritis. A total of 164 patients were included in this study. Physical examination and ultrasound examination were used to evaluate 30 joints of the wrist and hand. According to the clinical symptoms, the patients were divided into subclinical synovitis (SS) group and clinical synovitis (CS) group. The wrist and hand joints of patients with rheumatoid arthritis between the two groups were evaluated by semi-quantitative grading of musculoskeletal ultrasound, including synovitis, Power Doppler signal, joint effusion and bone erosion. We found that the total score of semi-quantitative ultrasound, synovitis score and Power Doppler signal score in the SS group were lower than those in the CS group (P<0.05). There was no significant difference in joint effusion score and bone erosion score (P>0.05). In the analysis of laboratory examination, the value of anti-RA33 antibody and ESR of SS group were decreased than that of CS group, with statistically significant difference (P=0.004), while that of RF, AKA and CCP had no significant difference between the two groups (P>0.05). In this study, the author also compared the tenosynovitis between the two groups. There was statistically significant difference (P=0.033). In conclusions, semi-quantitative grading of musculoskeletal ultrasound has certain diagnostic value for the diagnosis of subclinical synovitis in wrist and hand lesion.

[Agreement between ultrasound-detected inflammation and clinical signs in ankles and feet joints in patients with rheumatoid arthritis]

OBJECTIVE

To investigate the agreement between clinical signs (tenderness and/or swelling) in ankles and feet joints and ultrasound findings in patients with rheumatoid arthritis (RA).

METHODS

RA patients with at least 1 tender and/or swollen joint in bilateral ankles and metatarsophalangeal (MTP) joints detected by physical examination were enrolled and underwent ultrasound examination by greyscale (GS) and power Doppler (PD) mode. The agreement between clinical signs and ultrasound-detected inflammation (joint effusion, synovitis, or tenosynovitis) was analyzed.

RESULTS

In the study, 113 consecutive RA patients were included, with mean age of (52.5±12.6) years, median duration of 60 (13, 129) months, mean disease activity score in 28 joints based on erythrocyte sedimentation rate [DAS28 (ESR)] of 5.1±1.7, mean disease activity score in 28 joints based on C reactive protein[DAS28 (CRP)]of 4.6±1.5. The tenderness and swelling was most commonly detected in ankles (52.7% and 31.9%, respectively), while GS (+) synovitis was most frequently detectable in MTP2 (34.1%), followed by ankles (32.7%) and MTP1 (27.9%), and PD (+) synovitis was most frequently detectable in MTP1 (14.2%), followed by ankles (12.4%) and MTP2 (10.6%). The prevalence of tenosynovitis was 41.1%, which mostly located in tibialis posterior tendon (22.1% of GS positive and 17.6% of PD positive). The highest prevalence of joint effusion was detected in ankles (9.7%), while that of bone erosion in MTP5 (19%). The overall concordance rate between positive clinical signs and ultrasound-determined joint inflammation was poor in the above joints (κ < 0.2, P < 0.05), in which swelling had the highest κ coefficient with ultrasound-determined joint inflammation in ankles (κ=0.225, P < 0.05). Moreover, swelling had the highest κ coefficient with synovitis in ankles (κ=0.231, P < 0.05).The concordance between tenosynovitis and signs in ankles was also poor (κ < 0.20, P < 0.05). There was no significant agreement between joint effusion and clinical signs (P > 0.05).

CONCLUSION

The overall concordance between clinical signs and inflammation on ultrasound was poor in ankles and feet joints. Tenderness and swelling was more common in ankles, while more lesions were detected by ultrasound at MTP joints. Ultrasound is useful in assessing the lesions besides physical examination in patients with RA.

Application of Automated Hand Ultrasound Scanning and a Simplified Three-Joint Scoring System for Assessment of Rheumatoid Arthritis Activity

Ultrasound can be used to objectively diagnose and evaluate disease activity in patients with rheumatoid arthritis (RA). We aimed to determine the value of a new automated hand ultrasound (AHUS) scanning device and a simplified 3-joint ultrasound scoring system (US3) in detecting synovitis in RA. We compared AHUS and traditional ultrasound (US) scanning in detecting synovial hyperplasia (SH), joint effusion, bone erosion and power Doppler (PD) synovitis in 49 patients. In addition, we compared the value of US3 (in which 3 proximal interphalangeal [PIP] and/or metacarpophalangeal [MCP] joints with the highest scores for swelling and tenderness were evaluated) with the 22-joint ultrasound scoring system (US22) in 26 patients. Almost perfect κ coefficients (0.86-0.937) were obtained between AHUS and traditional US in detecting SH, joint effusion, bone erosion and PD synovitis (p < 0.001). The intra-class correlation coefficient (ICC) between AHUS and traditional US was 0.955-0.995. Of the US3 findings in AHUS, SH synovitis and PD synovitis were positively correlated with DAS28-CRP (adjusted R² = 0.421, p < 0.0001; adjusted R² = 0.365, p < 0.0001). US3 was highly correlated with US22 in detecting SH and PD synovitis (R = 0.792, p < 0.01; R = 0.948, p < 0.01). Compared with US22, a more significant correlation was identified between US3 scores and most clinical and laboratory values. In conclusion, AHUS performed comparably to traditional US in detecting synovitis in RA, and US3 was highly consistent with US22 in assessing synovitis and was positively correlated with RA disease activity.

Ultrasound shows swollen joints are the better proxy for synovitis than tender joints in DMARD-naïve early psoriatic arthritis

Objective

To evaluate the relationship between clinical examination/US synovitis in DMARD-naïve early PsA.

Methods

Eligible patients underwent matched clinical/US 44-joint assessment for tender and/or swollen joints (TJ/SJ) and US synovitis [grey scale (GS) ≥ 2 or power Doppler (PD) ≥ 1]. Statistical agreement between TJ/SJ, GS ≥ 2 and PD ≥ 1 was calculated by prevalence-adjusted and bias-adjusted κ (PABAK). To derive probabilities of GS ≥ 2/PD ≥ 1, mixed-effects logistic regression-modelled odds of US synovitis in TJ/SJ were conducted.

Results

In 155 patients, 5616 joints underwent clinical/US examination. Of these joints, 1039 of 5616 (18.5%) were tender, 550 of 5616 (9.8%) were swollen, 1144 of 5616 (20.4%) had GS ≥ 2, and 292 of 5616 (5.2%) had PD ≥ 1. GS ≥ 2 was most prevalent in concomitantly tender and swollen joints [205 of 462 (44%)], followed by swollen non-tender joints [32 of 88 (36.4%)], tender non-swollen joints [148 of 577 (25.7%)] and non-tender non-swollen joints (subclinical synovitis) [759 of 4489 (16.9%)]. Agreement between SJ/PD ≥ 1 was high at the individual joint level (82.6–96.3%, PABAK 0.65–0.93) and for total joints combined (89.9%, PABAK 0.80). SJ/GS ≥ 2 agreement was greater than between TJ/GS ≥ 2 [73.5–92.6% vs 51.0–87.4% (PABAK 0.47–0.85 vs PABAK 0.35–0.75), respectively]. Swelling was independently associated with higher odds of GS ≥ 2 [odds ratio (OR) (95% CI); 4.37 (2.62, 7.29); P < 0.001] but not tenderness [OR = 1.33 (0.87, 2.06); P = 0.192]. Swelling [OR = 8.78 (3.92, 19.66); P < 0.001] or tenderness [OR = 3.38 (1.53, 7.50); P = 0.003] was independently associated with higher odds of PD ≥ 1.

Conclusion

Synovitis (GS ≥ 2 and/or PD ≥ 1) was more likely in swollen joints than in tender joints in DMARD-naïve, early PsA. Agreement indicated that swollen joints were the better proxy for synovitis, adding to greater understanding between clinical and US assessments.

Positive rate and prognostic significance of the superb microvascular imaging signal in joints of rheumatoid arthritis patients in remission with normal C-reactive protein levels and erythrocyte sedimentation rates

PURPOSE

This study aimed to evaluate the positive rate and prognostic significance of superb microvascular imaging (SMI) in rheumatoid arthritis (RA) patients in remission with normal C-reactive protein (CRP) levels and erythrocyte sedimentation rates (ESR).

METHODS

The study enrolled 112 RA patients, and ultrasound (US) assessment was performed on 28 joints of each patient.

RESULTS

The SMI signal-positive rates for each joint were: metacarpophalangeal (MCP) joints: 20.5%, wrist joints: 43.8%, metatarsophalangeal (MTP) joints: 17.0%, and other foot joints: 25.0%. Investigation of the prognostic significance of the SMI signal in each joint revealed that only in the MTP joints was the total score of the SMI signal in the patients with relapse significantly higher than that in the patients with remission (P = 0.01). Comparison of the receiver operating characteristics curves for predicting relapse showed that the area under the curve (AUC) of the MTP joints was the highest (AUC = 0.66) of the investigated joints. The optimal threshold for the total MTP SMI score was 1 (accuracy = 83.3%). Positive/negative data of the SMI signal in the MTP joints were not significantly associated with the values of conventional disease activity markers.

CONCLUSION

In RA patients in remission with normal CRP and ESR levels, the percentage of positive SMI signal was highest in the wrist joints. However, the accuracy of the SMI signal for predicting relapse was greatest for the MTP joints, suggesting that US assessment of the MTP joints by SMI is useful for predicting relapse in these patients.

Role of joint damage, malalignment and inflammation in articular tenderness in rheumatoid arthritis, psoriatic arthritis and osteoarthritis

OBJECTIVES

To determine whether clinical tenderness can be considered a sign of inflammatory joint activity in patients with rheumatoid arthritis (RA), osteoarthritis (OA) or psoriatic arthritis (PsA) and to assess other possible factors associated with tenderness.

METHODS

Patients diagnosed with RA, PsA and OA underwent clinical and ultrasound examination of wrists and finger joints. Radiographs of the hands were scored for erosions, joint space narrowing (JSN), osteophytes and malalignment. A binary damage score (positive if ≥1 erosion, JSN and/or presence of malalignment) was calculated. Differences in grey scale signs of synovitis and power Doppler (PD) between tender non-swollen (TNS) versus non-tender non-swollen (NTNS) joints were calculated. Disease duration was assessed,<2 years was regarded as early and >5 years as long-standing arthritis.

RESULTS

In total, 34 patients (9 early and 14 long-standing) from patients with RA, 31 patients (7 early and 15 long-standing) with PsA and 30 with OA were included. We found equal frequencies of PD signal between TNS and NTNS joints in RA (p=0.18), PsA (p=0.59) or OA (p=0.96). However, PD had a significant association with tenderness in early arthritis both in RA (p=0.02) and in PsA (p=0.02). The radiographic damage score showed significant association with tenderness in RA (p<0.01), PsA (p<0.01) and OA (p=0.04).

CONCLUSION

Tenderness might not always be a sign of active inflammation in RA, PsA and OA. While tenderness in early arthritis may be more related to inflammation, established disease is better explained by joint damage and malalignment.

MAST3 modulates the inflammatory response and proliferation of fibroblast-like synoviocytes in rheumatoid arthritis

Via promoting synovitis, pannus growth and cartilage/bone destruction, fibroblast-like synovial cells (FLSs) play a significant role in the pathogenesis of rheumatoid arthritis (RA). In our study, rats were induced with complete freund's adjuvant (CFA) to be animal models for studying the RA pathogenesis. Microtubule-associated Serine/Threonine-protein kinase 3 (MAST3) has been documented to play a critical role in regulating the immune response of IBD (Inflammatory bowel disease) and involved in the process of cytoskeleton organization, intracellular signal transduction and peptidyl-serine phosphorylation, but its role in the progression of RA remains unknown and is warranted for investigation. So, we tried our best to investigate the mechanism and signaling pathway of MAST3 in RA progression. In the synovial tissue and FLSs of AA rats, we have found that MAST3 was significantly up-regulated than normal. Furthermore, MAST3 overexpression could promote proliferation and inflammatory response of FLSs. In the aspect of mechanism, we discovered that the expression of MAST3 might involve in NF-κB signaling pathway in RA. On the whole, our results suggested that MAST3 might promote the proliferation and inflammation of FLSs by regulating NF-κB signaling pathway.