Production of IgM rheumatoid factor by normal lymphocytes after stimulation with preparations containing IgM rheumatoid factor from patients with juvenile arthritis.

Preparations containing IgM rheumatoid factor (RF) and hidden IgM RF were isolated from the serum samples of nine patients with juvenile rheumatoid arthritis. Six of these preparations stimulated lymphocytes from normal donors to produce IgG and IgM, of which up to 11% had IgM RF activity. In contrast, the polyclonal activator pokeweed mitogen also stimulated IgM production, but only 1% had IgM RF activity. A relation between the activator and IgM RF or hidden IgM RF is suggested. This is based on the positive correlation between IgM RF concentration in these preparations and their ability to stimulate lymphocytes to produce IgG, IgM, and IgM RF. These data indicate that preparations from patients with juvenile rheumatoid arthritis containing IgM RF and hidden IgM RF are potent stimulants of lymphocytes from normal donors, with specific production of IgM RF.     

Systemic onset juvenile rheumatoid arthritis presenting with absence of B lymphocytes

Juvenile rheumatoid arthritis (JRA) is a complex disease involving the interactions of several cell populations with different mediators. Herein, we report a five-year-old girl with systemic-onset JRA. At admission, peripheral blood flowcytometric analysis showed the percentages of CD19⁺ and CD20⁺ B cells were <1%. These values returned to normal on the tenth day of steroid treatment. This is the first report of JRA presented with absence of B lymphocytes in the literature and suggested that lymphocytes subset analysis could change with treatment in patients with JRA. Different clinical signs and symptoms reflecting aspects of JRA are critical for the etiology of the disease and to identify new strategies for treatment.     

Growth and differentiation of B lymphocytes of patients with juvenile rheumatoid arthritis

We studied growth and differentiation of B lymphocytes of patients with juvenile rheumatoid arthritis (JRA) using B cell enriched populations. Mitogen stimulation led to similar proportionate increases in proliferation and immunoglobulin (Ig) secretion in cultures of patient and control lymphocytes. While there was no increase in proliferation, IgG secretion was increased in the absence of mitogen. Nonmitogen activated Ig synthesis could be reduced by replacing culture medium with fresh medium after 16-20 h in culture. It was partly reconstituted by addition of recombinant cytokines, interleukin (IL), IL-2, IL-4, or IL-6. Our results suggest there may be a population of B circulating B cells in patients with JRA and other rheumatic diseases which is sufficiently mature to differentiate and secrete Ig in response to cytokines alone.     

IgM rheumatoid factor plaque-forming cells in juvenile rheumatoid arthritis

Using a direct, plaque-forming cell (PFC) assay with sensitized sheep erythrocytes, lymphocytes that secrete IgM rheumatoid factors (RF) have been detected in the peripheral blood of patients with juvenile rheumatoid arthritis. Of 15 juvenile rheumatoid arthritis patients tested, 8 were seropositive and 7 were seronegative, but 6 of the seronegative patients had hidden 19S IgM-RF. Ten patients (5 seropositive and 5 with hidden 19S IgM-RF) demonstrated RF-PFC in their peripheral blood (range 15 to greater than 200 RF-PFC/10(6) mononuclear cells). Of 11 patients who had active disease, 10 had RF-PFC, and the 4 patients who had inactive disease had no PFC in their peripheral blood. HLA typing of all 15 patients revealed no correlation between the presence of RF-PFC and HLA type.     

Low molecular weight IgM and CD5 B lymphocytes in rheumatoid arthritis.

OBJECTIVES--To evaluate the role of low molecular weight (LMW) IgM and CD5 B cells in rheumatoid arthritis (RA) and to explore the possibility that LMW IgM is derived selectively from this subset of B cells. METHODS--LMW IgM in sera and culture supernatants was detected by a sensitive immunoblot technique with an enhanced chemiluminescence detection system. CD5 B cells were determined by FACScan cytometry. In vitro studies were established in culture plates containing pokeweed mitogen with or without 2-mercaptoethanol (2-ME). Supernatants were obtained from CD5 positive hybridomas and CD5 negative hybridomas. Other immunological indices were measured by laser nephelometry. RESULTS--Circulating LMW IgM was detected in all rheumatoid patients with significantly higher levels being observed in sero-positive patients. LMW IgM correlated significantly with total IgM and RF. Peripheral blood mononuclear cells (PBMC) from the majority of the patients with RA secreted LMW IgM in vitro as did mononuclear cells from a synovial fluid sample. The addition of low concentrations of 2-ME to the culture medium enhanced the proportions of secreted monomeric IgM. In contrast, PBMC from healthy subjects secreted only trace quantities of LMW IgM. In RA no significant correlations were observed between CD5 B cells and LMW IgM and RF. LMW IgM could be detected in the supernatants from both CD5+ and CD5- B cell lines. Finally, CD5 B cells were not significantly elevated in RA and levels remained constant over time. CONCLUSION--LMW IgM exists in high concentrations in RA sera and synovial fluid. Serum level correlates with RF and IgM. In vitro studies have suggested that the occurrence of LMW IgM may be due to an intrinsic defect(s) in the assembly of the IgM pentameric molecule. LMW IgM is unlikely to be derived solely from CD5 B cells.     

Phenotypes of T lymphocytes from peripheral blood and synovial fluid of patients with rheumatoid arthritis and juvenile rheumatoid arthritis. Evidence in favour of normal helper and suppressor functions of T lymphocytes from patients with juvenile rheumatoid arthritis

Lymphocytes from peripheral blood (PB) and synovial fluid (SF) from 21 patients with rheumatoid arthritis (RA) and 18 patients with juvenile rheumatoid arthritis (JRA) were studied with respect to T cell phenotypes using monoclonal antibodies in a rosette assay. The percentage of HLA-DR positive T cells was counted in PB and SF using indirect immunofluorescence. Suppressor cell activity of T cells from PB and SF was investigated by measuring the immunoglobulin production by pokeweed mitogen (PWM) stimulated B cells mixed with T cells at various ratios. The mean T4/T8 ratio was significantly lower in SF than in PB of both RA and JRA patients (p = 0.0062 and p less than 0.0001 respectively). The mean percentages of HLA-DR positive T cells were elevated in SF compared with PB in both patients groups (p less than 0.03 and p less than 0.04 in RA and JRA patients respectively). Mean suppressor cell activity and helper cell activity of T cells from SF and PB of JRA patients was normal. Thus there seems to be a dichotomy between the number of T8+ cells and suppressor cell function in mononuclear cells from SF of patients with JRA. This indicates that a considerable proportion of the T8+ cells in the SF do not have suppressor functions.     

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.     

Human alpha-interferon enhances in vitro IgM rheumatoid factor synthesis by lymphocytes from normal subjects and rheumatoid arthritis patients

Alpha-interferon (alpha-IFN) was added to pokeweed mitogen (PWM) or Epstein-Barr virus stimulated human peripheral blood mononuclear cell cultures from normal subjects or patients with rheumatoid arthritis (RA). Alpha-IFN enhanced in vitro production of PWM induced IgG and IgM, and significantly enhanced PWM induced IgM rheumatoid factor (IgM-RF) production by lymphocytes both from normal subjects and RA patients. Enhancement was recorded whether cells were preincubated with alpha-IFN for 16 hours or with alpha-IFN present throughout the culture period. Alpha-IFN did not enhance IgM-RF production in the absence of PWM or T cells. Enhancement of IgM-RF production was not seen in Epstein-Barr virus stimulated cultures.     

Hidden 19S IgM rheumatoid factor in adults with juvenile rheumatoid arthritis onset.

Forty-eight adult patients with juvenile rheumatoid arthritis (JRA) (onset before age 16 years) were evaluated at the age of 17 years or more for the presence of hidden 19S IgM rheumatoid factors (RF), i.e., 19S IgM RF that can be detected by the complement-dependent haemolytic assay in the IgM-containing fraction after separation of the serum by acid gel filtration. The average age of the patients was 25.3 years. The mean duration of disease was 16.5 years. Thirty-two of 48 patients (67%) showed the presence of hidden 19S IgM RF in their serum. Disease activity correlated with hidden RF titres in 62% (55/88) of the evaluations. The results indicate that patients with seronegative JRA onset continue to have significant titres of hidden 19S IgM RF in their sera into early adulthood.     

19S IgM forssman-type heterophhile antibodies in juvenile rheumatoid arthritis

Fifty-four sera from children with juvenile rheumatoid arthritis (JRA) were separated by gel filtration at pH 4.05. The serum and IgM and IgG-containing fractions were analyzed for heterophile antibodies by subjecting them to a hemolytic assay in tubes with the target cell a 1% washed sheep erythrocyte (SRBC) or beef erythrocyte (BRBC) in suspension. Thirty-three of 54 sera showed hemolytic antibody titers >1:640 against SRBC alone and 4 of 54 had titers >1:320 against SRBC and BRBC. All positive titers against SRBC and BRBC were associated with the IgM fraction. Differential absorption with SRBC, BRBC, and tissue sediment of homogenized guinea pig kidney revealed a Forssman specificity in 33 sera and Forssman and Hanganutziu-Deicher specificity in 4. The presence of heterophile antibodies in JRA correlated with the presence of hidden rheumatoid factor. There was also an increased incidence in patients with positive antinuclear antibodies and in teenaged females with polyarticular disease.     

Size distribution of lymphocytes in juvenile rheumatoid arthritis.

The diameters of circulating peripheral lymphocytes were measured in 28 children with juvenile rheumatoid arthritis. These were compared with lymphocyte measurements in 68 normal children, 19 children with asthma, and 12 children with cystic fibrosis. The average diameter of lymphocytes in normal children was found to be 11.2 microns. In contrast, the average diameter of lymphocytes in juvenile rheumatoid arthritis was 12.7 microns (P less than 0.0001). There were more lymphocytes with a diameter of 13 to 15 microns in children with juvenile rheumatoid arthritis than in normal children.     

Predicting pain among children with juvenile rheumatoid arthritis

Objective. Children and adolescents with juvenile rheumatoid arthritis (JRA) often report pain as a major symptom that affects their daily activities. Little is known about the factors that contribute to pain, however. Demographic, disease status, and social-psychologic variables were used to predict pain of JRA. Methods. Participants were 37 girls and 23 boys who were 7 to 17 years old. Measures included the Hopelessness Scale for Children, the Sadness Scale from the Differential Emotions Scale—IV, and the Social Support Questionnaire-Revised. A pain visual analogue scale served as the criterion measure. Results. Reported pain was modestly correlated with disease duration and age. A hierarchical regression indicated that the predictor variables accounted for a modest amount of variance in pain scores. Conclusions. The results suggest that the factors contributing to pain in children with JRA are different from those in adults with rheumatoid arthritis (RA). Research is needed to identify the psychologic and socioenvironmental variables that influence pain among children with JRA.     

Gastroduodenal lesions in children with juvenile rheumatoid arthritis.

BACKGROUND/AIMS: There are few studies about gastrointestinal abnormalities in patients with juvenile rheumatoid arthritis-probably due to the fact that this association is not frequently recognized. The aim of our study was to observe the prevalence of endoscopic gastroduodenal lesions in these patients. METHODOLOGY: Fourteen patients with juvenile rheumatoid arthritis, all of them using non-steroidal anti-inflammatory drugs associated or not with methotrexate, were assessed clinically and by endoscopy. Gastric antrum biopsy and Helicobacter pylori search were also performed. RESULTS: The mean age of the patients was 10.6 years (7 boys). Abdominal pain was observed in 27% of them. Macroscopic endoscopic lesions were found in 43% and infection by Helicobacter pylori in 57%. The correlation between anemia and endoscopic abnormalities was statistically significant (p < 0.05). CONCLUSIONS: Our data show that patients with juvenile rheumatoid arthritis have considerable susceptibility to gastroduodenal lesions, especially if they are using any drug association and present anemia.     

Increased responsiveness of rheumatoid B lymphocytes to stimulation by epstein-barr virus

Blood lymphocytes from rheumatoid patients and normal subjects were examined for responsiveness in culture to Epstein-Barr virus (EBV) infection by outgrowth assay and 3HTdR uptake. With both unseparated and B-cell-enriched lymphocytes the frequency and rate of outgrowth to form permanent cell lines were significantly higher for rheumatoid than for normal cells. In B-enriched rheumatoid preparations the proportion of responsive cells was also greater, and DNA synthesis was induced by a lower infecting dose of EBV in rheumatoid than in normal cells. The percentage of autologous T cells needed to ensure regression of B-cell proliferation in EBV-infected cultures was considerably higher with rheumatoid than with normal cells. These findings suggest that in rheumatoid arthritis the abnormal lymphocyte responsiveness to EBV has two components, a T-cell immunoregulatory defect, and a separate increased responsiveness of B cells to EBV.     

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.     

Hidden and classical 19S IgM rheumatoid factor in a juvenile rheumatoid arthritis patient

Hidden 19S IgM rheumatoid factors (RF), i.e., 19S IgM RF which can be detected in the IgM containing fraction after acid gel filtration of serum, are found in 59-68% of patients with juvenile rheumatoid arthritis (JRA). Their presence generally correlates with disease activity. We describe a 12 year-old female with a polyarticular onset of JRA who, during her first 15 months of disease, was seronegative but had hidden RF titers of 1:128----1:256. Inhibition studies on her hidden RF showed specificity for HIgG greater than RIgG and equal specificity for the human IgG subclasses (IgG1 = IgG3). In the second and third year of disease, she became seropositive with RF titers varying from 1:40 to 1:320 while her hemolytic titers on her IgM fractions were decreased from 1:128 to 1:32. Inhibition studies now demonstrated a higher avidity for RIgG; and HIgG3 inhibited more than HIgG1. These studies documented for the first time a JRA patient who early in the disease was negative for RF and positive for hidden RF, and who later became seropositive.     

Prevalence of IgA deficiency in children with juvenile rheumatoid arthritis

The purpose of this study was to investigate any association between IgA deficiency (IgAD) and juvenile rheumatoid arthritis (JRA) among Iranian children.This case-control study was carried out on 83 children who were diagnosed as JRA according to American College of Rheumatology (ACR) criteria; Patients were admitted at the rheumatology clinic of Children's Medical Center, (Tehran). Serum immunoglobulins concentrations were determined by nephelometry method. Control group was 112 healthy children who were matched for age and gender. Informed consent obtained from all parents.Selective IgA deficiency (sIgAD) was found only in a boy (1.2%) among JRA children; however, partial IgA deficiency was found in 6(7.1%) of patients with JRA and in 12(10.7%) of control subjects, this difference was not statistically significant (p=0.46). Immunoglobulins levels in patients with JRA (IgM: 126.7±57.2, IgG: 1182.3±351 and IgA:169.3±98) were significantly higher than their controls (IgM: 104±52, IgG:802±220 and IgA: 94.6±47) (p<0.05). Patients with growth failure had higher IgM, IgG and IgA levels in comparison with patients without growth failure; however, this difference was significant about IgM and IgG levels (p<0.05).In contrast to other similar studies, the number of IgAD did not differ significantly between JRA patients and their control counterpart; this might be partly due to the high rate of consanguineous marriages in Iran that resulted in increased prevalence of clinically undiagnosed partial IgAD in general population. Hence, future epidemiological studies are warranted to make it clear.     

Flow cytometry and cytoadherence studies of sera from children with juvenile rheumatoid arthritis and normal controls

Recently, antibodies reactive with T cell subpopulations have been reported to exist in children with active juvenile arthritis (JRA). In an attempt to verify and extend these observations, we have studied children with JRA for the presence of anti-T cell antibodies by flow cytometry and cytoadherence rosette techniques. T cells were isolated from peripheral blood mononuclear cells (PBL) by two methods: 1) Differential sedimentation of PBL rosetted with neuraminidase-treated sheep erythrocytes, and 2) removal of immunoglobulin positive PBL by rosetting with rabbit anti–human F(ab′)₂ coated bovine erythrocytes and differential sedimentation. Utilizing these methods to detect lymphoreactivity of JRA sera to either population of T cell isolates, we observed the binding of ultracentrifuged normal human sera (NHS) to be comparable to JRA sera (active and quiescent). NHS reacted with 15–25% of T cells. Further studies demonstrate that monomeric IgG was chiefly responsible for lymphoreactivity. The results of these studies are discussed in the context of previous observations.