Validation of Fully Automatic Quantitative Software for Finger Joint Space Narrowing Progression for Rheumatoid Arthritis Patients

In rheumatoid arthritis (RA), the radiographic progression of joint space narrowing (JSN) is evaluated using visual assessments. However, those methods are complicated and time-consuming. We developed an automatic system that can detect joint locations and compute the joint space difference index (JSDI), which was defined as the chronological change in JSN between two radiographs. The purpose of this study was to establish the validity of the software that automatically evaluates the temporal change of JSN. This study consisted of 39 patients with RA. All patients were treated with tocilizumab and underwent hand radiography (left and right hand separately) at 0, 6, and 12 months. The JSN was evaluated using mTSS (modified Total Sharp Score) by one musculoskeletal radiologist as well as our automatic system. Software measurement showed that JSDI between 0 and 12 months was significantly higher than that between 0 and 6 months (p < 0.01). While, there was no significant difference in mTSS between 0, 6, and 12 months. The group with higher disease activity at 0 months had significantly higher JSDI between 0 and 6 months than that with lower disease activity (p = 0.02). The automatic software can evaluate JSN progression of RA patients in the finger joint on X-ray.Electronic supplementary materialThe online version of this article (10.1007/s10278-020-00390-6) contains supplementary material, which is available to authorized users.     

Computer-Based Radiographic Quantification of Joint Space Narrowing Progression Using Sequential Hand Radiographs: Validation Study in Rheumatoid Arthritis Patients from Multiple Institutions

We have developed a refined computer-based method to detect joint space narrowing (JSN) progression with the joint space narrowing progression index (JSNPI) by superimposing sequential hand radiographs. The purpose of this study is to assess the validity of a computer-based method using images obtained from multiple institutions in rheumatoid arthritis (RA) patients. Sequential hand radiographs of 42 patients (37 females and 5 males) with RA from two institutions were analyzed by a computer-based method and visual scoring systems as a standard of reference. The JSNPI above the smallest detectable difference (SDD) defined JSN progression on the joint level. The sensitivity and specificity of the computer-based method for JSN progression was calculated using the SDD and a receiver operating characteristic (ROC) curve. Out of 314 metacarpophalangeal joints, 34 joints progressed based on the SDD, while 11 joints widened. Twenty-one joints progressed in the computer-based method, 11 joints in the scoring systems, and 13 joints in both methods. Based on the SDD, we found lower sensitivity and higher specificity with 54.2 and 92.8%, respectively. At the most discriminant cutoff point according to the ROC curve, the sensitivity and specificity was 70.8 and 81.7%, respectively. The proposed computer-based method provides quantitative measurement of JSN progression using sequential hand radiographs and may be a useful tool in follow-up assessment of joint damage in RA patients.     

Autoantibodies in Patients with Rheumatoid Arthritis

Aim:  The aim of this study is to examine the diagnostic value of autoanitbodies in patients suffering from rheumatoid arthritis. We evaluated the presence of the following autoantibodies: rheumatoid factor (RF), antinuclear antibodies (ANAs), antibodies against cadiolipin (a-CL) and antibodies against cyclic citrullinated peptide (anti-CCP).
Methods:  We studied the presence of RF, ANA, a-CL and anti-CCP in 40 patients with rheumatoid arthritis. Rheumatoid factor was measured using nephelometric method, while ANAs were examined by indirect immunofluorescence technique using Hep-2 cells as substrate. Sera that reacted at 1/80 dilution were classified as ANA positive. Positive sera were studied up to 1/1280 dilution. A-CL and anti-CCP were measured by enzyme-linked immunosorbent assay.
Results:  RF was positive in 30 patients (75%), ANA in 15 (37%), a-CL in 10 (25%) and anti-CCP in 36 (90%). Predominant pattern of nuclear staining of ANA-positive sera was homogenous and speckled type. ANA titres were particularly low; most patients (6) had ANA titre equal to 1/80, and five patients had a titre of 1/160, while only four out of 40 had an ANA titre of 1/320.
Conclusions:  Autoimmune disorders such as RA are characterized by various autoantibodies that usually are not specific, as they are present in many other diseases. However, RF and especially anti-CCP are very often and show higher specificity for RA, being useful diagnostic serological markers. On the other hand, ANA and a-CL are less common in RA paitents; they may be useful in terms of prognosis and treatment, but they always should be evaluated in correlation with the clinical features and the rest of the laboratory findings of each patient.     

Detection of T-Lymphocyte Subpopulations in the Peripheral Blood and the Synovium of Patients with Rheumatoid Arthritis and Juvenile Rheumatoid Arthritis Using Monoclonal Antibodies

Monoclonal antibodies with specificities for various human T-cell antigens were used in direct immunofluorescence to quantify the proportions of T lymphocytes with suppressor/cytotoxic-cell markers and with helper/inducer-cell markers and of T lymphocytes with HLA-DR antigens. Normal percentages of lymphocytes with suppressor/cytotoxic-cell markers were detected in the peripheral blood synovial fluid and synovial tissue lymphocytes from patients with juvenile rheumatoid arthritis (JRA) and rheumatoid arthritis (RA), respectively. Normal percentages of T lymphocytes with helper/inducer-cell markers were seen in the peripheral blood of RA and JRA patients and in the synovial tissues of RA patients. Slightly decreased percentages of cells with the helper/inducer-cell marker were detected in the synovial fluids of JRA patients. The proportions of HLA-DR-positive T lymphocytes were highly increased in the synovial fluid and synovial tissue, whereas the numbers of these cells in the peripheral blood were normal. No significant differences in T gamma cells were detected between peripheral blood, synovial fluid and synovial tissue of JRA patients or between peripheral blood and synovial tissue of RA patients.     

Concanavalin-A-Activated Suppressor Cells in Patients with Juvenile Rheumatoid Arthritis

Concanavalin-A-induced suppressor cell activity was investigated in 63 patients with a definite diagnosis of juvenile rheumatoid arthritis. Peripheral blood lymphoid cells from these patients did not have the same ability as cells from normal individuals to suppress the proliferative response of autologous cells, responding to phytohaemaglutinin, Candida albicans antigen, or allogeneic cells. No correlation was found between suppressor activity, disease activity, or number of joints involved. Nor was there any significant association between decreased suppressor cell activity and HLA-A, -B, -C, -D antigens, although there was a tendency towards association between decreased suppressor cell activity and HLA-B27.     

Impaired Akt Phosphorylation in Monocytes of Patients with Rheumatoid Arthritis

It has been proposed that the Akt kinase pathway provides a regulatory mechanism to limit the inflammatory response. We examined the activation of Akt upon lipopolysaccharide (LPS) challenge in monocytes of patients with rheumatoid arthritis (RA) and correlated it with disease activity. Twelve subjects with recent‐onset, DMARD‐naïve RA, thirteen patients with chronic, DMARD therapy–non‐responding RA and 27 healthy volunteers provided whole blood samples for phosphospecific flow cytometric measurement of unstimulated and LPS‐stimulated Akt phosphorylation at serine 473 in monocytes, determined in relative fluorescence units (RFU). Activation capability, that is responsiveness of monocytes, was determined as the difference between stimulated and unstimulated samples and compared between groups using Mann–Whitney test. CRP and ESR, swollen and tender joint counts, patients’ global assessment of disease activity, DAS28 score and plasma IL‐6 determined by ELISA were correlated with Akt activation using Spearman method. Median (interquartile range) Akt activation capability was significantly lower in DMARD‐naïve (379 RFU [285, 432], P = 0.016) and even lower in DMARD‐non‐responding RA (258 RFU [213, 338], P < 0.001), compared to healthy controls (505 RFU[408, 639]) and showed a negative correlation with swollen joint count (r = −0.48, CI −0.78 to −0.05, P = 0.014), CRP (r = −0.42, CI −0.80 to −0.02, P = 0.039) and plasma IL‐6 levels (r = −0.44, CI −0.65 to −0.17, P = 0.001). In conclusion, Akt activation capability of monocytes is low in early untreated RA and even lower in chronic, DMARD‐non‐responding RA, suggesting a role for Akt pathway in the pathogenesis of RA.     

Noninvasive Measurement of Acceleration at the Knee Joint in Patients with Rheumatoid Arthritis and Spondyloarthropathy of the Knee

Spondyloarthropathy represents a group of joint diseases with a tendency to reactive new bone formation. Spondyloarthropathy includes Reiter's syndrome, ankylosing spondylitis, and the arthropathy of inflammatory diseases (ulcerative colitis and Crohn's disease). Usually, an extensive investigation is required to distinguish spondyloarthropathy of the knee joint from rheumatoid arthritis. Recently, Reddy et al. (Ann. Biomed. Eng. 23:78–84, 1995) have developed the accelerometry technique to characterize various types of arthritis. The question remains if noninvasive acceleration measurements can be used to distinguish between spondyloarthropathy and rheumatoid arthritis. An ultraminiature accelerometer was placed on the patella, and the subject was asked to rhythmically rotate the knee from 90 flexion to full extension. Results have shown that the mean power of acceleration signal in the range of 100–500 Hz is significantly different (p < 0.05) for spondyloarthropathy patients when compared to rheumatoid arthritis patients. The noninvasive accelerometry technique represents a potential tool for characterization of spondyloarthropathy patients. © 2001 Biomedical Engineering Society. PAC01: 8719St, 8719Xx, 0630Gv     

Urinary Excretion of Thiol Compounds in Patients with Rheumatoid Arthritis

The objective of the present study was to assess the excretion of urinary thiol compounds in patients with active and inactive rheumatoid arthritis (RA). Urinary thiol compounds were measured by the method of Kokonov (M. T. Kokonov, Lab. Delo 5:273–276, 1965) in 51 outpatients with active and inactive RA. Those with active disease had significantly higher levels of urinary thioamine excretion.     

T-Cell Immunoregulatory Functions in Rheumatoid Arthritis Patients

We have studied the immunoregulatory function of T8+ (suppressor/cytotoxic) and Leu3a+ (inducer/helper) T cells from rheumatoid arthritis (RA) patients by measuring the effect of these T-cell subpopulations on the generation of immunoglobulin-secreting cells by normal allogeneic B cells after stimulation with pokeweed mitogen (PWM) in vitro. When T8+ or Leu3a+ cells from blood or synovial tissue from nine patients were substituted for T8+ or Leu3a+ cells, respectively, from normal blood mononuclear cells (MNC), RA T8+ cells showed an increased suppressor activity, whereas RA Leu3a+ cells were, except for one patient, weak augmentors. Unreplaced normal MNC and MNC replaced with allogeneic normal T-cell subpopulations responded equally to PWM. When T8+ plus Leu3a+ cells from the same patient replaced normal T cells, high B-cell responses were detected. Normal T8+ plus Leu3a+ cells generally supported the response to a lower degree. Substitution with two allogeneic T-cell subpopulations did not result in a B-cell response to PWM. Thus, whereas RA T8+ seemed to be strong suppressors and RA Leu3a+ cells weak augmentors by themselves, together they are possibly able to generate a B-cell stimulatory potential that might be of pathogenetic significance in the patients.     

Quantitative In Vivo HR-pQCT Imaging of 3D Wrist and Metacarpophalangeal Joint Space Width in Rheumatoid Arthritis

In this technique development study, high-resolution peripheral quantitative computed tomography (HR-pQCT) was applied to non-invasively image and quantify 3D joint space morphology of the wrist and metacarpophalangeal (MCP) joints of patients with rheumatoid arthritis (RA). HR-pQCT imaging (82 μm voxel-size) of the dominant hand was performed in patients with diagnosed rheumatoid arthritis (RA, N = 16, age: 52.6 ± 12.8) and healthy controls (CTRL, N = 7, age: 50.1 ± 15.0). An automated computer algorithm was developed to segment wrist and MCP joint spaces. The 3D distance transformation method was applied to spatially map joint space width, and summarized by the mean joint space width (JSW), minimal and maximal JSW (JSW.MIN, JSW.MAX), asymmetry (JSW.AS), and distribution (JSW.SD)—a measure of joint space heterogeneity. In vivo precision was determined for each measure by calculating the smallest detectable difference (SDD) and root mean square coefficient of variation (RMSCV%) of repeat scans. Qualitatively, HR-pQCT images and pseudo-color JSW maps showed global joint space narrowing, as well as regional and focal abnormalities in RA patients. In patients with radiographic JSN at an MCP, JSW.SD was two-fold greater vs. CTRL (p < 0.01), and JSW.MIN was more than two-fold lower (p < 0.001). Similarly, JSW.SD was significantly greater in the wrist of RA patients vs. CTRL (p < 0.05). In vivo precision was highest for JSW (SDD: 100 μm, RMSCV: 2.1%) while the SDD for JSW.MIN and JSW.SD were 370 and 110 μm, respectively. This study suggests that in vivo quantification of 3D joint space morphology from HR-pQCT, could improve early detection of joint damage in rheumatological diseases.     

IgG Complexes in Serum of Rheumatoid Arthritis Patients

Sera from 171 consecutive rheumatoid arthritis patients were tested for direct platelet aggregation. Thirty-three of 146 rheumatoid factor (RF)-positive sera and 3 of 25 RF-negative sera gave platelet aggregation, indicating the presence of circulating IgG complexes equal to or greater than 19S. Forty randomly selected sera were analyzed by gel filtrations on Sepharose 4B and Sephadex G-200 and by sedimentation analysis. IgG complexes, mainly of intermediate sizes, were demonstrated in 54% of sera with RF titers of 40 to 640 and in 80% of sera with an RF titer equal to or greater than 1280. The intermediate complexes could be absorbed on and eluted from cross-linked human IgG, thus indicating IgG-RF to be a dominant constituent of the complexes.     

Antibody-Dependent Cytotoxicity Mediated by Cells Eluted from Synovial Tissues of Patients with Rheumatoid Arthritis and Juvenile Rheumatoid Arthritis

Cell suspensions containing an average of 78% lymphocytes were obtained from synovial tissues of 26 patients with rheumatoid arthritis and 10 patients with juvenile rheumatoid arthritis. These cells were shown to mediate cytotoxicity against ⁵¹Cr-labeled chicken erythrocytes sensitized with a rabbit anti-chicken erythrocyte antiserum. Nylon column filtration of the cells increased the proportion of lymphocytes and usually also the cytotoxicity, which suggested that at least some of the effector cells were lymphocytes. The cytotoxic activity of the cells obtained from rheumatoid synovial tissue was always lower than that obtained with the patients' peripheral blood lymphocytes. No significant change in cytotoxicity of normal peripheral blood lymphocytes was observed after these cells had been treated in the same manner as the rheumatoid synovial tissues.     

类风湿关节炎患者血清IgG-IgM型类风湿因子免疫复合物检测的临床意义

目的 探讨血清IgM型类风湿因子与变性IgG抗原形成的复合物定量检测对类风湿关节炎诊断的临床意义.方法 收集类风湿关节炎(RA)患者36例、非RA患者41例和体检健康者40名作为研究对象.用包被有鼠抗人μ链抗体的ELISA孔板及HRP标记的兔抗人IgG对血清中IgM型类风湿因子(RF)与变性IgG抗原形成的免疫复合物水平进行检测,同时用胶乳凝集法检测RF,并对二者结果进行相关性分析;用ELISA试剂盒进行抗环瓜氨酸肽抗体(抗CCP抗体)的定性检测,并比较其与IgG-IgM型RF免疫复合物对于RA诊断的敏感性和特异性.结果 待检血清最佳稀释倍数为100倍.IgG-IgM型RF免疫复合物对于RA的敏感性为72.2％,特异性为95.3％.IgG-IgM型RF免疫复合物OD值与RF阳性程度相关系数为0.687(P ＜0.01).结论 血清IgG-IgM型RF免疫复合物水平对RA具有较高的敏感性和特异性,可作为RA诊断的参考指标.     

The Presence of Anti-Protein A Antibodies in Patients with Rheumatoid Arthritis

Sixteen patients with rheumatoid arthritis (RA) were examined for the presence of anti-protein A antibodies. The F(ab')2 preparations from five RA patients showed significant binding to IgG-free protein A on ELISA. The protein A binding was further examined by immunoblotting. The F(ab')2 preparations of high protein A-binding protein gave a specific reaction with IgG-free protein A on nitrocellulose paper. This demonstrates the presence of anti-protein A antibodies in patients with RA. Those RA patients with anti-protein A antibodies had more active disease as judged by the Lansbury's activity index. The level of serum rheumatoid factor (RAHA) was significantly higher in patients with anti-protein A antibodies than in those without anti-protein A antibodies.     

微粒子酶免疫化学发光法和ELISA定量检测CCP抗体的临床应用评价

目的:应用化学发光法、酶联免疫吸附试验(ELISA)定量检测类风湿性关节炎(RA)患者抗环瓜氨酸多肽(CCP)抗体的含量,探讨CCP抗体在RA早期诊断和治疗中的作用.方法:选取69例RA、30例强直性脊柱炎(AS)、33例干燥综合征(SS)患者、61例健康体检人群,分别用化学发光、ELISA检测其血清CCP抗体的含量....     

Human Monoclonal IgG Rheumatoid Factors from the Synovial Tissue of Patients with Rheumatoid Arthritis

We have established IgG rheumatoid factor (RF)-secreting hybridoma cell lines from the synovial tissues of two patients (TS and SJ) with rheumatoid arthritis (RA) und one (KL) with the polyarlicular form of juvenile rheumatoid arthritis (JRA). The IgG RF bind human and rubbit IgG and all except one form intracellular complement-fixing complexes indicative of a self-association process. The possibility of IgG RF for self association and immune complex formation is a feature thought to be important for the inflammatory processes in RA. Of the IgG RF-secretingcell lines established, three clones from patient SJ and one from patient KL are of the IgG I k isotype while five clones from patient TS are of the IgG2λ isotype.     

Demonstration of Anti-Rubella Antibody-secreting Cells in Rheumatoid Arthritis Patients

In the present study we describe a plaque-forming cell assay using erythrocytes coated with viral antigen, which detected anti-viral antibody-secreting cells against various viral antigens. These anti-viral antibody-secreting cell were studied in normal individuals with known viral infections and in rheumatoid arthritis patients. Rubella anti-viral antibody-secreting cells were present after induction in the peripheral blood of eight out of ten patients. No plaques were seen before induction. Synovial tissue of seven patients out of ten showed rubella-antigen-specific plaques before induction. In all three patients tested, the numbers of plaques increased after induction. The peripheral blood of only one patient showed plaque-forming cells against mumps virus and cytomegalovirus (CMV) antigen. No other patients showed any plaque against CMV, respiratory syncytial virus, mumps virus, measles virus, adenovirus, and varicella zoster virus antigens. The method appears to be promising in studying viral antibody-secreting cells in human immunopathology.     

Con A-induced Suppressor Cell Activity and T-lymphocyte Subpopulations in Peripheral Blood Lymphocytes of Patients with Rheumatoid Arthritis and Juvenile Rheumatoid Arthritis

Suppressor cell activity was investigated in peripheral blood lymphocytes from twenty patients with rheumatoid arthritis (RA) and twenty patients with juvenile rheumatoid arthritis (JRA) using a concanavalin A/mixed lymphocyte culture assay. The mean suppression in the RA patients was slightly reduced compared with the suppressor cell activity in adult controls (25 +/- 5% suppression compared with 37 +/- 5%; P less than 0.05, Student's t test), whereas the JRA patients had normal suppressor cell activity (mean 46 +/- 5% versus 43 +/- 5% in healthy children matched for age and sex). The RA patients had normal proportions of T-cell subpopulations, 13.3% T gamma cells and 49.8% T mu cells, compared with 13.8% and 58.0% in controls. The JRA patients, however, had a significantly reduced mean percentage of T gamma cells, 6.6%, compared with 13.8% in healthy children (P less than 0.05, Mann-Whitney U-test). The mean percentage of T mu cells was 53.7%, versus 56.2% in the controls. The relation between suppressor cell activity and suppressor cells enumerated by membrane markers is discussed.