Anti-agalactosyl IgG Antibody Research Articles

Anti-agalactosyl IgG antibody in ankylosing spondylitis and psoriatic arthritis

Anti-agalactosyl IgG antibody (anti-Gal(0) IgG) has been regarded as a useful serological marker for rheumatoid arthritis (RA). It is unknown whether it is also elevated in serum and implicated in the pathogenesis of joint inflammation in seronegative spondyloarthropathy (SpA) such as ankylosing spondylitis (AS) and psoriatic arthritis (PsA). Sera were collected from 43 patients with AS or PsA with axial joint involvement, 22 patients with RA, and 25 healthy normal individuals for the detection of anti-Gal(0) IgG with a cup-type lectin enzyme immunoassay (Eitest CA(.)RF). The disease activity of the AS/PsA was evaluated by Bath Ankylosing Spondylitis Disease Activity Score (BASDAI), the serum C-reactive protein (CRP) and IgA were measured by nephelometry, and erythrocyte sedimentation rate (ESR) was measured by Westergren's method. The median titers of anti-Gal(0) IgG were significantly elevated in patients with RA (167.85, 15.73 approximately 797.58 AU/mL) and AS/PsA (186.15, 34.71 approximately 651.19 AU/mL), compared to those of the normal controls (13.04, 12.00 approximately 202.43 AU/mL). The titers of the anti-Gal(0) IgG in patients with AS/PsA were correlated to the BASDAI scores (r (2) = 0.422, SEE = 1.443, p < 0.001) and serum CRP (r (2) = 0.345, SEE = 2.434, p < 0.001) but not to IgA (r (2) = 0.0259, SEE = 126.30, p < 0.001) or ESR (r (2) = 0.171, SEE = 31.053, p = 0.0059). Collectively, the anti-Gal(0) IgG is elevated and vaguely correlated with the disease activity of AS/PsA although its titers in these patients were erratic. The result of the present investigation has suggested that anti-Gal(0) IgG may be more ubiquitously present in inflammatory arthritides including RA or SpA.

The diagnostic utilities of anti-agalactosyl IgG antibodies, anti-cyclic citrullinated peptide antibodies, and rheumatoid factors in rheumatoid arthritis

The purpose of this study was to investigate the diagnostic utilities of anti-agalactosyl IgG antibody (CARF), anti-cyclic citrullinated peptide (CCP) antibody and rheumatoid factor (RF) in rheumatoid arthritis (RA), non-RA rheumatic diseases, and chronic viral hepatitis. The authors determined serum levels of CARF and anti-CCP2 by ELISA and IgM-RF by a immunonephelometric method in 834 controls and in 397 patients with the following conditions: RA (100), non-RA rheumatic diseases [systemic lupus erythematosus (SLE) 30, primary Sjogren's syndrome 18, systemic sclerosis 30, inflammatory myositis 19], chronic viral hepatitis B and C (HBV 100, HCV 100). The sensitivities of CARF (83%) and anti-CCP (85%) were significantly higher than that of RF (75%, p=0.01, respectively) in RA, and the specificity of anti-CCP (98%) was significantly higher than those of CARF (92%) and RF (90%, p<0.001, respectively). A comparison of receiver operating characteristic (ROC) curves revealed that the diagnostic accuracies of CARF and anti-CCP were superior to that of RF (CARF vs. RF, p=0.008, anti-CCP vs. RF, p=0.017) in RA. CARF positivity was significantly higher than those of anti-CCP (p=0.007) and RF (p=0.008) in systemic sclerosis, and the positivity of CARF was significantly higher than that of anti-CCP in Sjogren's syndrome (p=0.016). Furthermore, CARF had significantly higher positivity than anti-CCP or RF in chronic viral hepatitis B and C. Finally, the titers of these three markers in RA were significantly higher than in non-RA rheumatic diseases and in chronic viral hepatitis B and C. Our results suggest that anti-CCP is the most useful serologic marker for the differentiation of RA and non-RA rheumatic diseases, and chronic viral hepatitis B and C.

Anti-agalactosyl IgG antibodies in Thai patients with rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis

This study was performed to determine the prevalence of anti-agalactosyl IgG antibodies in Thai patients with RA, systemic lupus erythematosus (SLE) and systemic sclerosis (SSc), and determine the sensitivity and specificity of anti-agalactosyl IgG antibodies in the diagnosis of RA in comparison with IgM-rheumatoid factor (IgM-RF) and anti-cyclic citrullinated peptide (anti-CCP) antibodies. Serum samples were obtained from 100 patients with RA, 50 cases of SLE, 50 cases of SSc, and 100 healthy controls and analyzed for the presence of anti-agalactosyl IgG antibodies, IgM-RF and anti-CCP antibodies. A serum value greater than mean + 2 standard deviation of normal value of anti-agalactosyl IgG antibodies and anti-CCP antibodies was considered positive. The prevalence of anti-agalactosyl IgG antibodies in RA, SLE, and SSc patients was 88.0%, 14.0%, and 12.0%, respectively. The serum level of anti-agalactosyl IgG antibodies in patients with RA (227.10 +/- 353.64 AU/mL) was significantly higher than those in SLE (11.84 +/- 52.04 AU/mL), SSc (18.85 +/- 99.60 AU/mL), and healthy controls (2.14 +/- 1.97 AU/mL), (p < 0.001). There was a good correlation between the log serum level of anti-agalactosyl IgG antibodies and IgM-RF (r = 0.92, p < 0.001), anti-CCP antibodies and IgM-RF (r = 0.49, p < 0.001), and anti-agalactosyl IgG antibodies and anti-CCP antibodies (r = 0.55, p < 0.001). The sensitivity and specificity in the diagnosis of RA was 88.00% and 96.00% for anti-agalactosyl IgG antibodies, 90.00% and 99.00% for anti-CCP antibodies, and 91.00% and 95.00% for IgM-RF, respectively. The serum level of anti-agalactosyl IgG antibodies was significantly higher in RA than in SLE, SSc, and healthy controls. There was a good correlation between serum levels of anti-agalactosyl IgG antibodies, anti-CCP antibodies, and IgM-RF. These three tests had comparable sensitivity and specificity.

Diagnostic utility of anti-cyclic citrullinated peptide antibody in early rheumatoid arthritis

Current therapeutic strategies against rheumatoid arthritis (RA) employ increasingly aggressive regimens from an early stage of the disease ; thus, serological markers more specific than IgM-rheumatoid factor (IgM-RF) are desirable. Anti-cyclic citrullinated peptide (anti-CCP) antibody has been reported as a useful and highly specificity marker for the diagnosis of RA. To clarify the diagnostic utility of anti-CCP antibody in early RA, we measured serum concentrations of anti-CCP antibody, IgM-RF, anti-agalactosyl IgG antibody and matrix metalloproteinase (MMP)-3 in 184 polyarthritis patients who showed onset symptoms within the previous 2 years. The diagnostic sensitivity of anti-CCP antibody in early RA was 60.0%, equivalent to IgM-RF (66.3%) and anti-agalactosyl IgG antibody (66.0%). Specificity, positive predictive values and diagnostic accuracy of anti-CCP antibody were the best among the four tested makers. In 38 patients who initially did not meet the ACR criteria for RA, but were diagnosed with RA during the course, the diagnostic sensitivity of anti-CCP antibody was 55.3%. On the other hand, the disease activity score (DAS) 28 of anti-CCP antibody positive and the negative patients was 5.16 and 5.34, respectively. Our data indicated that determination of anti-CCP antibody was useful for early diagnosis of RA.

Increased Serum Levels of Nɛ-(hexanoyl)lysine, A New Marker of Oxidative Stress, in Systemic Sclerosis

To determine serum levels of N(epsilon)-(hexanoyl)lysine (HEL), a new marker of oxidative stress, and its clinical association in patients with systemic sclerosis (SSc). Serum HEL levels from 26 patients with limited cutaneous SSc (lSSc), 34 with diffuse cutaneous SSc (dSSc), 20 with systemic lupus erythematosus (SLE), 20 with dermatomyositis (DM), and 40 healthy individuals were examined by enzyme linked immunosorbent assay. Serum HEL levels were elevated in patients with SSc compared with healthy controls (n = 40) with similar levels between patients with lSSc and dSSc (p < 0.0001). SSc patients with elevated HEL levels had increased serum levels of anti-agalactosyl IgG antibody, rheumatoid factor (RF), and IgM than those with normal HEL levels (p < 0.05). HEL levels correlated positively with anti-agalactosyl IgG antibody (p = 0.013, r = 0.408) and RF titer (p = 0.0028, r = 0.426). Our results suggest that oxidative stress may play an important role in immunological abnormalities of SSc, especially in the production of autoantibodies including anti-agalactosyl IgG antibody and RF.

Rheumatoid cranial pachymeningitis successfully treated with long-term corticosteroid

We report a 68-year-old man without clinical history of rheumatoid arthritis who presented with acute bilateral palsy of the IX and X cranial nerves secondary to pachymeningitis confirmed on cranial MRI. Rheumatoid factor in both serum and cerebrospinal fluid and anti-agalactosyl IgG antibody in serum were positive. The radiographs of hands and feet revealed signs of early rheumatism. The dural biopsy specimen showed chronic inflammation with infiltration of lymphocytes and histiocytes. A diagnosis of rheumatoid cranial pachymeningitis was made. Treatment with long-term corticosteroid was excellently effective.

Magnetic resonance imaging of palindromic rheumatism

A 44-year-old man with intermittent asymmetric migratory oligoarthritis lasting the recent decade was admitted to our hospital. Considerable specific biomarkers for rheumatoid arthritis such as anti-agalactosyl IgG antibody are all negative. He was diagnosed as palindromic rheumatism (PR). Although hand X-rays showed no remarkable findings, hand magnetic resonance imaging (MRI) detected pannus and bone erosion. PR is defined as the disease characterized by short-lasting attacks of acute oligoarthritis, without radiographic changes. To our knowledge, the findings of MRI for PR have not been previously described. We propose that MRI findings in patients with PR is useful tool to distinguish PR from rheumatoid arthritis (RA) or other RA related diseases.

Autoantibodies to cyclic citrullinated peptide 2 (CCP2) are superior to other potential diagnostic biomarkers for predicting rheumatoid arthritis in early undifferentiated arthritis

We evaluated the diagnostic value of anti-cyclic citrullinated peptide 2 (anti-CCP2) antibodies and other potential diagnostic biomarkers (IgM rheumatoid factor, anti-agalactosyl IgG antibodies, matrix metalloproteinase 3, C-reactive protein) for predicting early development of rheumatoid arthritis (RA). Patients were defined as having recent-onset undifferentiated arthritis (UA) if they had developed arthritis in two or more joints within the previous 2 years and could not be classified with a well-defined arthropathy. Baseline levels of biomarkers were measured in blood samples collected at the entry of the study and the patients were followed for 1 year to monitor development of RA. Diagnoses of RA and non-RA arthropathies were made according to individual standard diagnostic criteria. A total of 146 patients were enrolled in the study. In the follow-up year, 18 patients developed RA, 54 developed non-RA arthropathies, and 60 remained in the UA category. The sensitivity and specificity of the presence of anti-CCP2 antibodies for the diagnosis of RA were 83.3 and 93.0%, respectively. The positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of anti-CCP2 antibodies for RA (65.2, 97.2, and 91.7%, respectively) were higher than for any other biomarker. Combination of anti-CCP2 with any other biomarker only slightly improved each diagnostic value compared to the presence of anti-CCP2 alone. Among the anti-CCP2-positive patients, the average titer was significantly higher in those with RA than in non-RA or UA patients (163.7 +/- 138.4 vs 55.2 +/- 72.0 U/ml, p = 0.017). Anti-CCP2 antibodies are superior to any other single biomarker for predicting early development of RA in patients with recent-onset UA and the diagnostic value of anti-CCP2 alone is similar to that for biomarker combinations. Moreover, the anti-CCP2 antibody titer is useful to discriminate between patients at high risk for early developing RA from those at risk of developing non-RA arthropathies.

The Examination of Rheumatoid Factor and Other Serum Markers in Rheumatoid Arthritis

Rheumatoid factor (IgM-RF) has been widely used to diagnose rheumatoid arthritis (RA) in clinical practice. We investigated the RA diagnostic performances of anti-cyclic citrullinated peptide antibody (anti-CCP), matrix metalloproteinase-3 (MMP-3), anti-agalactosyl IgG antibody (CA*RF), and anti-calpastatin antibody (ACA) in comparison with IgM-RF. Among 68 RA patients, IgM-RF was positive in 31 (45.6%) and negative in 37 (54.4%). In the IgM-RF-positive group, positivity in anti-CCP, CA*RF, and ACA was 97%, 100%, and 97%, respectively, although that in MMP-3 (74%) was inferior to the others. On the other hand, in the IgM-RF-negative group, positivity in anti-CCP, MMP-3, and ACA was 73%, 81%, and 86%, respectively, although that in CA*RF was only 59%. We conclude that the combination of IgM-RF and anti-CCP/ACA will provide an accurate diagnosis of RA in clinical practice.

Serum levels of anti-agalactosyl IgG antibodies in mixed connective tissue disease

Serum levels of anti-agalactosyl IgG antibodies in mixed connective tissue disease

Rheumatoid factor isotypes and anti-agalactosyl IgG antibodies in systemic sclerosis

Rheumatoid factor isotypes and anti-agalactosyl IgG antibodies (anti-AG IgG) have been reported to be detected and correlated with the disease activity in some collagen diseases. To study the frequency and the clinical significance of IgM, IgG and IgA rheumatoid factor (IgM-RF, IgG-RF and IgA-RF) and anti-AG IgG in patients with systemic sclerosis (SSc). Seventy-nine serum samples from patients with SSc were examined by specific enzyme-linked immunosorbent assays. The levels of IgM-, IgG-, IgA-RF and anti-AG IgG were significantly higher in SSc patients than in normal healthy controls. The levels of IgM- and IgA-RF were significantly higher in patients with diffuse cutaneous SSc than in those with limited cutaneous SSc. IgM-, IgG- and IgA-RF and anti-AG IgG were significantly elevated in 39%, 32%, 23% and 35% of 79 SSc patients, respectively. The prevalence of pulmonary fibrosis, oesophageal involvement and cutaneous telangectasias in patients with elevated IgA-RF levels was significantly higher than in those with normal levels. The incidence of pitting scars of digits in those with elevated IgG-RF levels and the incidence of contracture of phalanges in those with elevated IgM-RF levels were significantly higher than in those with normal levels. The frequency of increased erythrocyte sedimentation rate in patients with elevated IgG-RF and the frequency of increased C-reactive protein in those with elevated IgM-RF were significantly greater than in those with normal levels. IgM-, IgG-, IgA-RF and anti-AG IgG can be serum indicators of specific clinical manifestations in SSc patients.