Synthesis of IgM, IgG and IgA in rheumatoid arthritis.

We studied the production of immunoglobulins by lymphocytes separated from the blood of 15 rheumatoid arthritis (RA) patients, of 12 patients suffering from other connective tissue diseases (CTD), and of 18 healthy controls. The production of IgM, IgG and IgA in pokeweed-mitogen-stimulated cultures was measured by counting the number of plaque-forming cells (PFC) and by determining the concentration of secreted immunoglobulins by means of an enzyme immunoassay. Synthesis of immunoglobulins, particularly IgM and IgG, was lower than in other CTD patients or controls. The IgM response of RA patients was 20% and 29% (PFC and Ig concentrations) that of the controls. The respective figures for IgG were 33% and 53% and for IgA 61% and 72%.     

Relationship of serum IgG rheumatoid factor to IgM rheumatoid factor and disease activity in rheumatoid arthritis

Rheumatoid factors (RF) constitute the major autoantibodies in rheumatoid arthritis (RA). RF are directed against IgG Fc, are polyclonal, and are predominantly of the IgG and IgM classes. RF may participate in both synovial and extraarticular inflammation in RA, although the precise roles of serum IgG and IgM RF are unclear. The purpose of our study was to correlate serum IgG RF with serum IgM RF levels measured by radioimmunoassay and with clinical disease activity in 42 prospectively evaluated seropositive RA patients. IgM RF correlated with IgG RF levels and articular disease activity. IgG RF correlated with IgM RF but not with articular disease activity when adjusted for IgM RF.     

Rheumatoid factor and serum IgG, IgM and IgA levels in rheumatoid arthritis with vasculitis.

The authors report a significant increase in the rheumatoid factor titre in rheumatoid arthritis patients with vasculitis. A significant rise in IgG and IgA levels was found in uncomplicated RA, when compared with a normal population. The IgM levels were not found to be elevated in this group of RA patients. In the RA patients with vasculitis, on the contrary, the three Ig classes are increased when compared with the normal population, and the IgM level is increased when compared with the uncomplicated RA group. Significant relation was found between log IgM and log R.F. titre in the RA group with vasculitis. It is shown that the mild reduction of serum (by dithiothreitol 0.004 M) causes a complete negativity of the R. F. in all cases. It is concluded that the haemagglutination and the latex precipitation in vitro are induced by IgM-R. F. and not by IgG and IgA-R. F. molecules. Only free sites of IgM-R.F. play a functional role in the determination of the R. F. -titre. The authors postulated that increase in IgM in RA patients with vasculitis is partially due to the presence of free IgM-R. F. molecules in serum. Finally it is concluded that hidden IgM-R. F. molecules in patients with lower R. F. titre are not quantified by immunodiffusion methods.     

Serum aminoterminal type III procollagen peptide in early rheumatoid arthritis: relation to disease activity and progression of joint damage

Serum levels of the aminoterminal type III procollagen peptide (S-PIIINP) have been used as markers of proliferative inflammation in rheumatoid arthritis (RA) and a prognostic significance has been suggested. To test this further we have measured S-PIIINP longitudinally for 2 years in 66 patients with definite RA and a disease duration of less than 2 years, and related the levels to clinical, biochemical, and radiographic findings. In this patient group the correlations between S-PIIINP and ESR and CRP, respectively, were higher than those obtained between S-PIIINP and articular indices, and markedly higher than in patients with RA of longer duration. Patients with normal mean levels of S-PIIINP during the study period had a significantly slower rate of radiographic progression than patients with elevated mean levels of S-PIIINP. ESR yielded in general higher correlations with the joint damage process than did S-PIIINP. The correlations between S-PIIINP and the joint damage scores increased with time. A multiple regression analysis showed that ESR explained most of the variance in joint damage progression over 2 years, but S-PIIINP added independent information. About one third of the variance could be explained by the two variables.     

Prevalence of IgM, IgA and IgG rheumatoid factors in juvenile rheumatoid arthritis

Using an enzyme immunoassay, sera from 50 children with juvenile rheumatoid arthritis (JRA) and 39 controls were tested for IgM, IgA and IgG rheumatoid factors (RF). RF of the IgM and IgA isotypes were present in 11 (22%) patients, but in only one control (p = 0.008). IgG RF was present in the sera of 2 (4%) patients and in none of the controls (p = 0.21). Of the 22 patients with IgM RF or IgA RF, only 3 sera (14%) contained RF of both isotypes. IgM RF was more common in patients with polyarticular disease, while IgA RF was more common in patients with pauciarticular disease. These results indicate that IgM and IgA RF are present in a significant minority of JRA patients and suggest that there is independent expression of the respective RF isotypes.     

IgM,IgA and IgG rheumatoid factors in patients with rheumatoid arthritis and normal donors

Summary IgM, IgA, and IgG Rheumatoid Factors (RF) were measured by ELISA assay in serum from 26 patients with definite rheumatoid arthritis (RA) and 11 normal controls. IgM-RF was assayed by ELISA, radioimmunoassay,and also by the standard latex fixation test in all sera from RA patients. In patients with RA quantitative amounts of IgM, IgA, and IgG-RF as estimated by ELISA were highly correlated. Significant correlations were found between a physician's rating of disease activity and IgG-RF (r=0.44; p<.02) and IgA-RF (r=0.38; p=.06 but not for IgM-RF as measured in any of the three assays.During the course of this work F.S. was supported by a NATO fellowship from the Consiglio Nazionale delle Ricerche, Roma, Italy.     

Serum and synovial fluid IgG,IgA and IgM antigammaglobulins in rheumatoid arthritis

Antigammaglobulins of IgG, IgA and IgM classes were measured in normal individuals and in patients with osteoarthritis or rheumatoid arthritis. Serum IgG and IgA and synovial fluid IgG antigammaglobulin levels were significantly higher in patients with rheumatoid arthritis than in other individuals, with highest levels occurring in patients with positive latex fixation tests. IgM antigammaglobulins were elevated only in patients with latex positive rheumatoid arthritis. Increased serum levels of IgG, IgA and IgM antigammaglobulins were each associated with clinical findings of severe rheumatoid arthritis. Increased levels of serum and synovial fluid IgG and IgM antigammaglobulins were each associated with diminished serum and synovial fluid complement levels.     

IgM rheumatoid factor (RF), IgA RF, IgE RF, and IgG RF detected by ELISA in rheumatoid arthritis.

One hundred patients with rheumatoid arthritis (RA), of whom 73 were seropositive by latex or Waaler-Rose (WR) assays, or both, 100 healthy subjects, and 102 diseased controls (22 patients with systemic lupus erythematosus (SLE) and 80 with bronchial asthma) were evaluated for the presence of IgM rheumatoid factor (RF), IgA RF, IgE RF, and IgG RF by an enzyme linked immunosorbent assay (ELISA). Ninety two per cent, 65%, 68%, and 66% of the patients with RA were found to be positive for IgM, IgA, IgE, and IgG respectively. A positive correlation existed between the levels of IgM RF and IgA RF on the one hand and disease activity on the other, and the levels of IgM RF and IgA RF correlated with the levels of circulating immune complexes as measured by a C1q binding assay. The presence of extra-articular features also correlated positively with the levels of IgA RF and IgE RF. Five out of six patients with Sjögren''s syndrome had very high levels of IgA RF. Of 47 patients typed for HLA-DR, DR1 and DR2 were significantly more frequent in those with the highest levels of IgM RF. Conversely, DR3 was associated with low levels or absence of IgA RF and IgE RF. These results suggest that immune response genes may regulate the level of different RF isotypes. The frequencies of IgM, IgA, IgE, and IgG RF were 59%, 36%, 9%, and 27% respectively in SLE and 25%, 2.5%, 70%, and 59% in bronchial asthma.     

Long term progression of joint damage in rheumatoid arthritis.

Joint damage in rheumatoid arthritis is assessed radiologically. Previous studies have not examined in detail its long term progression. We evaluated the overall changes of peripheral joint damage radiologically in 50 rheumatoid patients followed up at one rheumatology centre for 10 years. All peripheral joints were scored in 12 groups with Larsen's standard films at 0 and 10 years. In 48 cases the total scored deteriorated (mean increase 13% maximum damage). There was no different pattern of progression in any of the patients, though seropositive patients had more initial damage and a greater rate of progress. The wrist and small joints of the feet were most affected initially. During the 10 years most progression occurred in the wrist, knee, and metacarpophalangeal joints. Progression occurred in both initially normal and abnormal joints. By 10 years only 16.5% joint groups showed no damage. Complete destruction was most common in the wrist, knee, and small joints of the feet. Damage to the hands and wrists have a god indication of overall changes at 0 and 10 years and also the increase in damage (correlation coefficients were from r = 0.74 to r = 0.85). These results show that specific joints are involved in different stages of the disease. Some joints are frequently involved and some less often. The hands and the wrists give a reasonable picture of the overall progression of damage.     

ELISA determined IgM, IgG and IgA rheumatoid factors in rheumatoid arthritis and in other connective tissue diseases

We used an adaptation of an enzyme-linked immunoadsorbent assay (ELISA) to determine serum levels of IgM, IgG and IgA rheumatoid factors (RF) in 50 patients with classic or definite rheumatoid arthritis (RA) according to the ARA criteria, balanced for positive or negative-routine Latex-RF reaction. A control group of 50 young normal subjects and a reference group of 44 patients with other connective tissue diseases (OCTD) were also studied. We confirmed the high sensibility of the method, together with its good specificity and reproducibility. For the IgM RF a very significant correlation was found between ELISA results and Latex-RF titration (p less than 0.001). Many Latex-RF negative RA patients had high ELISA levels of IgM RF, suggesting that this assay reveals, at least in part, hidden or non-agglutinating IgM RF. Among the OCTD group only some SLE cases, mainly Latex-RF positive, had enhanced IgM RF on ELISA. Considered quantitatively, IgG RF did not play a significant diagnostic role for RA (p greater than 0.05), because they were also found, with widely dispersed values, in normal subjects, and because the mean increase in RA patients was relatively small. Interestingly, IgA RF were above the normal range in many RA patients, both Latex-RF positive or negative. The mean values differed significantly from those of controls (p less than 0.005), and a correlation was observed between IgA RF levels and IgA containing immune-complexes. Normal IgA RF values were observed in SLE patients, even if Latex-RF positive, suggesting that their increase in RA patients is not the mere expression of a polyclonal B cell activation.     

Slow progression of joint damage in early rheumatoid arthritis treated with cyclosporin a

Objective. To evaluate the ability of low-dose cyclosporin A (CsA) to control radiologic disease progression, and to assess the clinical efficacy and tolerability of CsA, compared with conventional disease-modifying antirheumatic drugs (DMARDs), in patients with early active rheumatoid arthritis (RA). Methods. In this long-term, multicenter, prospective, open, blinded end point, randomized trial, 361 consenting patients with early (< 4 years since diagnosis) active RA were enrolled. Of the eligible patients, 167 were treated with CsA at 3 mg/kg/day, and 173 with DMARDs. The decision to use conventional antirheumatic drugs as controls was based on the fact that joint erosion could be expected to occur after 1 year regardless of the type of DMARD being used. The possibility of switching therapies in both groups was intended to keep the largest possible number of patients in the study. Results. Blinded evaluation of hand and foot radiographs after 12 months of treatment showed that CsA led to a significant (P < 0.001) delay in the mean ± SD progression in the eroded joint count (1.3 ± 3.1 versus 2.4 ± 3.0 for the control group) and in the joint damage score (3.6 ± 8.9 versus 6.9 ± 9.1 for the control group), both measured by the Larsen-Dale method. When only the patients without erosion at baseline were considered (37 in the CsA-treated group and 54 in the control group), erosion appeared in only 10.8% of the CsA-treated patients, but in 51.8% of the controls (P = 0.00005). Low-dose CsA was as effective as traditional DMARDs in controlling clinical symptoms. Maintenance on the initially prescribed treatment regimen (“survival on treatment”) was also better at 12 months with CsA than with DMARDs (89.2% versus 77.5%; P = 0.002). The tolerability of CsA was acceptable. Conclusion. These 12-month results suggest that low-dose CsA decreases the rate of further joint damage in previously involved joints as well as the rate of new joint involvement in previously uninvolved joints, in patients with early RA.     

Progression of joint damage in early rheumatoid arthritis: association with HLA-DRB1, rheumatoid factor, and anti-citrullinated protein antibodies in relation to different treatment strategies

OBJECTIVE: To determine the association of HLA-DRB1, rheumatoid factor (RF), and anti-citrullinated protein antibody (ACPA) status with progression of joint damage in early rheumatoid arthritis (RA) treated according to different treatment strategies. METHODS: The present study was conducted using data from the BeSt study (Behandelstrategie?n voor Reumatoide Artritis [treatment strategies for rheumatoid arthritis]), a randomized trial comparing 4 targeted (toward achievement of a Disease Activity Score [DAS] of < or =2.4) treatment strategies: sequential monotherapy (group 1), step-up combination therapy (group 2), initial combination therapy with methotrexate, sulfasalazine, and prednisone (group 3), and initial combination therapy with methotrexate and infliximab (group 4), in 508 patients with early RA. Multivariate logistic regression analysis was used to predict progressive disease (increase of Sharp/van der Heijde score over 2 years beyond the smallest detectable change [4.6]) according to the presence or absence of the shared epitope (SE), DERAA, RF, and ACPA, with correction for other baseline characteristics. RESULTS: Progressive disease could not be predicted by presence of the SE: the odds ratio in groups 1, 2, 3, and 4, respectively, was 1.4, 2.6, 1.9, and 3.0. DERAA carriership did not protect against progressive disease (odds ratio 0.4, 1.4, 0.9, and 0.9 in groups 1, 2, 3, and 4, respectively). RF positivity and ACPA positivity predicted progressive disease in group 1 (odds ratio 4.7 [95% confidence interval 1.5-14.5] for RF and 12.6 [95% confidence interval 3.0-51.9] for ACPA), but not in groups 2-4 (for RF, odds ratio [95% confidence interval] 1.5 [0.5-4.9], 1.0 [0.3-3.3], and 1.4 [0.4-4.8] in group 2, group 3, and group 4, respectively; for ACPA, odds ratio [95% confidence interval] 3.4 [0.8-14.2], 1.7 [0.5-5.4], and 1.8 [0.5-6.8] in group 2, group 3, and group 4). CONCLUSION: In patients with early RA treated with the goal of tight control of the DAS, no significant association between HLA-DRB1 status and radiographic progression was found. RF and ACPA were predictive of progressive disease only in patients treated with sequential monotherapy. These observations suggest that effective treatment can prevent radiographic progression, even in patients with risk factors for severe damage.     

The effects of tobacco smoking and rheumatoid factor seropositivity on disease activity and joint damage in early rheumatoid arthritis

OBJECTIVE: To study the effect of tobacco smoking and rheumatoid factor (RF) isotypes on disease activity and joint damage in early rheumatoid arthritis (RA). METHODS: One hundred early RA patients were followed prospectively for 2 yr. They were evaluated at recruitment and at 6 and 24 months. Sociodemographic information included smoking history, and radiographs of hands and feet were obtained. RF was monitored by IgM- and IgA-specific RF enzyme-linked immunosorbent assay and by agglutination, and serial measurements were also obtained for C-reactive protein. The influence of tobacco smoking and RF positivity on disease outcome was evaluated using multivariate analysis. Covariates for the regression analysis included sex, age, coffee consumption and IgA-RF positivity. RESULTS: A gradient of increase in disease activity was observed from never smokers to former smokers to current smokers during the 2 yr of observation, defined by number of swollen joints (SJC), tender joints (TJC) and visual analogue scale for pain (P<0.001, P=0.02 and P=0.005, respectively), but smoking status did not influence radiological progression. Ever smokers were more often IgA RF positive (P<0.05). IgA RF-positive patients had more active disease (SJC P=0.002, TJC P=0.01) and showed more radiological progression (P<0.0001) compared with IgA RF-negative patients. Of the RF-positive patients 22% had elevated IgM RF without IgA RF and these patients showed similar disease activity and radiological joint progression to the RF-negative patients. None of these associations were explained by possible confounders. CONCLUSION: Tobacco smoking has an adverse effect on patients with early RA and this is possibly immunologically mediated. IgM RF does not predict poorer prognosis in RA unless it is associated with a concomitant elevation of IgA RF.     

IgM, IgG and IgA rheumatoid factors (antiglobulins) in early rheumatoid arthritis and their production of articular index over one year

An enzyme-linked immunosorbent assay was used to detect antiglobulins (rheumatoid factors, RF) of various classes in 33 patients with recently diagnosed rheumatoid arthritis and to follow their progress with 3-monthly checks for 1 year. For RF, IgA-RF and IgM-RF showed greater sensitivity than the latex test, either or both being positive in 76%. There was no correlation between any of the measures of RF and patient's clinical status as judged by articular index (AI), or serum CRP level. For individual patients, RF levels varied considerably between assessments. The best predictors of clinical status over 1 year were the initial AI and the latex test for RF. While class-specific measurement of RF is more sensitive than the latex test, the variation of individual classes of antiglobulins over time within individual patients makes them less helpful as predictors of disease progress.     

IgG and IgM rheumatoid factors in rheumatoid arthritis. Quantitative response to penicillamine therapy and relationship to disease activity

Penicillamine treatment of patients with rheumatoid arthritis (RA) leads to falling titers of agglutinating IgM rheumatoid factor (RF), but its effect on IgG RF has not been described. Using specific solid phase radioimmunoassays, we have determined serial levels of IgM RF and IgG RF in 18 patients receiving penicillamine for 1 year, and correlated the results with the change in RA activity. Mean IgM RF levels fell to 76 +/- 10% (mean +/- SEM) after 3 months, and 30 +/- 5% of the pretreatment value after 1 year of penicillamine treatment. This decline was greater than that for total IgM (P less than 0.0001), indicating a selective reduction of RF. Patients receiving maintenance doses of 750 mg/day manifested more rapid and greater decreases than did those given 250 mg/day. In contrast, serial mean IgG RF levels did not change significantly, and actually increased in 6 of 18 cases. At onset, there was a significant correlation with erythrocyte sedimentation rate for both IgM RF (r = 0.535, P = 0.05) and IgG RF levels (r = 0.570, P = 0.02). But changes in RF concentration demonstrated no correlation with changes in either erythrocyte sedimentation rate or joint score over the 1-year period, suggesting that circulating IgM RF or IgG RF levels may be unrelated to the degree of RA activity.     

Serum MMP-3 and MMP-1 and progression of joint damage in early rheumatoid arthritis

OBJECTIVE: Expression and activation of matrix metalloproteinases such as MMP-3 (stromelysin-1) and MMP-1 (collagenase-1) are increased in patients with rheumatoid arthritis (RA). Previous negative reports of their value as predictors of joint damage may be due to the lack of a large longitudinal study of early RA patients. This study evaluated their use in assessing early untreated patients with RA and predicting subsequent joint damage. METHODS: Ninety-eight patients with early untreated RA of less than 12 months duration and 20 normal controls had baseline serum samples tested with a double-antibody enzyme-linked immunosorbent assay for each of MMP-1 and MMP-3. The subsequent changes in Larsen score (DeltaLarsen) and Health Assessment Questionnaire (DeltaHAQ) over the first 12 months were recorded. RESULTS: Baseline serum levels of MMP-3 and MMP-1 correlated significantly with baseline C-reactive protein (CRP) (r=0.42 and 0.49, P<0.001), DeltaHAQ (r=0.32 and 0.30, P<0.01) and DeltaLarsen (r=0.23 and 0.32, P<0.05) respectively. Analysis of the group of patients with a normal CRP at presentation (n=21) showed correlation of the baseline MMP-3 and MMP-1 with the presence of erosive disease during the first 12 months (r=0.52 and 0.65 respectively, P<0.05). Logistic regression analysis, in the patients who were non-erosive at presentation, showed that the strongest correlation with progression in Larsen score was the baseline MMP-3 level (r=0.30, P=0.01). CONCLUSIONS: Baseline serum MMP-1 and MMP-3 levels correlate with disease activity and predict functional and radiographic outcome in early untreated RA. They may have a particular value in predicting the progression of erosive disease in patients who are not erosive at presentation.     

Matrix metalloproteinases-3, -8, -9 as markers of disease activity and joint damage progression in early rheumatoid arthritis

OBJECTIVE: To analyse the relation between systemic levels of pro-MMP-3, -8, and -9 matrix metalloproteinase (MMP) activity in alpha(2) macroglobulin (alpha(2)M)/MMP complexes and the progression of joint destruction in patients with recent onset rheumatoid arthritis (RA). METHODS: 109 patients with RA of recent onset were entered into this longitudinal study. Patients were followed up for two years; clinical data, blood samples, and radiographs were obtained at baseline and at 1 and 2 years. Serum levels of MMPs were measured by sandwich ELISA and MMP activity assays. RESULTS: During the two years joint damage progressed from 0 to 10 (median Sharp score, p<0.001). Stable levels of pro-MMP-3 and a significant decrease in the levels of pro-MMP-8 and -9 and alpha(2)M/MMP complexes were seen throughout the two years. Regression analysis showed that serum pro-MMP-3 levels at disease onset were independently associated with the progression of joint damage (B=0.7, 95% CI 0.3 to 1.1, p=0.001). Based on the rate of joint destruction, patients were divided into two subgroups: patients with mild and severe joint damage progression. The pro-MMP-3 levels were significantly higher in the group with severe compared with mild disease at all times. Levels of pro-MMP-8 and -9 were decreased in both groups, whereas alpha(2)M/MMP complex levels decreased in the group with mild disease only. CONCLUSION: Serum levels of the MMPs studied are associated with disease activity, but serum pro-MMP-3 levels at the onset of disease are also predictive of joint damage progression.     

IgG rheumatoid factor in early rheumatoid arthritis as a predictor of radiological changes and disease activity

Our objective was to confirm whether IgG rheumatoid factor (IgG RF) assessed in early rheumatoid arthritis (RA) could be a prognostic factor of disease activity and articular destruction. The IgG RF index was assessed by a kit (Eitest IgG RF) in 46 patients with early RA (disease duration less than 1 year). Damage score (DS), carpal height ratio (CHR), clinical variables, and conventional RF values were evaluated at the initial visit and 2–3 years (average 2.5 years) after the initial visit. The incidence of IgG RF was 23.9% at the initial visit. Patients with positive IgG RF showed higher DS and higher Lansbury’s index in the final observation. They also showed a greater increase of DS and a greater decrease of CHR. The IgG RF index correlated with the final DS and final Lansbury’s index. We conclude that although the incidence was low, the IgG RF index in early RA could be a prognostic factor in radiographic changes and disease activity 2–3 years after the initial visit.