The association between rheumatoid arthritis and the HLA antigen DR4

Presence of Autoantibodies in Males and Females With Rheumatoid Arthritis: A Systematic Review and Metaanalysis

OBJECTIVE

Rheumatoid arthritis (RA) is more common in females, and although the cause of RA is unknown, it is characterized by the production of autoantibodies. The aims of this study were to determine whether RA-associated autoantibodies are more often found in females than males and to identify factors that influence the relationship between sex and seropositivity.

METHODS

Databases were searched and studies of RA (N ≥ 100) were included if they reported proportion of seropositive patients with RA by sex. Metaanalyses and metaregression were conducted using the random-effects model. Covariates regressed were smoking, age, BMI, Health Assessment Questionnaire-Disability Index (HAQ-DI), and the Disease Activity Score in 28 joints (DAS28).

RESULTS

Eighty-four studies with a total of 141,381 subjects with rheumatoid factor (RF) seropositivity and 95,749 subjects with anticitrullinated protein antibody (ACPA) seropositivity met inclusion criteria. The mean age of participants ranged from 37 to 68 years and the proportion of female subjects ranged from 9% to 92%. Results indicated that females were less likely than males to be seropositive: odds ratio (OR) 0.84 [95% CI 0.77-0.91] for RF and OR 0.88 [95% CI 0.81-0.95] for ACPA. BMI, smoking, mean age, DAS28, and HAQ-DI did not affect the relationship between sex and seropositivity.

CONCLUSION

Although studies report that females have higher RA disease activity than males and that seropositivity predicts worse outcomes, females were less likely to be seropositive than males.

Rheumatoid Arthritis Accompanying Diffuse Panbronchiolitis

A 58-year-old woman with rheumatoid arthritis (RA) visited our hospital complaining of a persistent cough and sputum for the past year. She had a high cold hemagglutinin titer and chronic sinusitis. Chest computed tomography revealed bilateral diffuse centrilobular nodules, bronchiectasis, and bronchial wall thickening. A surgical lung biopsy was performed that confirmed diffuse panbronchiolitis (DPB) because of the lymphocytic and plasmacytic infiltrates in the respiratory bronchioles. Her condition improved after the administration of clarithromycin. Several cases of RA complicating DPB have previously been reported, but only in Japan. We need to consider DPB as a bronchiolitis types accompanying RA among Japanese patients.

Autoantibodies as Diagnostic Markers and Mediator of Joint Inflammation in Arthritis

Rheumatoid arthritis is a systemic, polygenic, and multifactorial syndrome characterized by erosive polyarthritis, damage to joint architecture, and presence of autoantibodies against several self-structures in the serum and synovial fluid. These autoantibodies (anticitrullinated protein/peptide antibodies (ACPAs), rheumatoid factors (RF), anticollagen type II antibodies, antiglucose-6 phosphate isomerase antibodies, anticarbamylated protein antibodies, and antiacetylated protein antibodies) have different characteristics, diagnostic/prognostic value, and pathological significance in RA patients. Some of these antibodies are present in the patients' serum several years before the onset of clinical disease. Various genetic and environmental factors are associated with autoantibody production against different autoantigenic targets. Both the activating and inhibitory FcγRs and the activation of different complement cascades contribute to the downstream effector functions in the antibody-mediated disease pathology. Interplay between several molecules (cytokines, chemokines, proteases, and inflammatory mediators) culminates in causing damage to the articular cartilage and bones. In addition, autoantibodies are proven to be useful disease markers for RA, and different diagnostic tools are being developed for early diagnosis of the clinical disease. Recently, a direct link was proposed between the presence of autoantibodies and bone erosion as well as in the induction of pain. In this review, the diagnostic value of autoantibodies, their synthesis and function as a mediator of joint inflammation, and the significance of IgG-Fc glycosylation are discussed.

On Peptides and Altered Peptide Ligands: From Origin, Mode of Action and Design to Clinical Application (Immunotherapy)

T lymphocytes equipped with clonotypic T cell antigen receptors (TCR) recognize immunogenic peptides only when presented in the context of their own major histocompatibility complex (MHC) molecules. Peptide loading to MHC molecules occurs in intracellular compartments (ER for class I and MIIC for class II molecules) and relies on the interaction of the respective peptides and peptide binding pockets on MHC molecules. Those peptide residues not engaged in MHC binding point towards the TCR screening for possible peptide MHC complex binding partners. Natural or intentional modification of both MHC binding registers and TCR interacting residues of peptides - leading to the formation of altered peptide ligands (APLs) - might alter the way peptides interact with TCRs and hence influence subsequent T cell activation events, and consequently T cell effector functions. This review article summarizes how APLs were detected and first described, current concepts of how APLs modify T cellular signaling, which biological mechanisms might force the generation of APLs in vivo, and how peptides and APLs might be used for the benefit of patients suffering from allergic or autoimmune diseases.

Macrophage Inflammatory Protein-1 Alpha (MIP-1 alpha)/CCL3: As a Biomarker

Macrophage inflammatory protein-1 alpha (MIP-1α/CCL3) is a chemotactic chemokine secreted by macrophages. It performs various biological functions, such as recruiting inflammatory cells, wound healing, inhibition of stem cells, and maintaining effector immune response. It activates bone resorption cells and directly induces bone destruction. Cells that secrete MIP-1α/CCL3 are increased at sites of inflammation and bone resorption. MIP-1α/CCL3 plays an important role in the pathogenesis of various inflammatory diseases and conditions that exhibit bone resorption, such as periodontitis, multiple myeloma, Sjögren syndrome, and rheumatoid arthritis. Biological fluids from patients with these diseases exhibit elevated levels of MIP-1α/CCL3. This finding indicates that MIP-1\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ \alpha $$\end{document}α/CCL3 protein may have diagnostic potential for the detection of several inflammatory diseases and conditions. This chapter discusses the biological functions of MIP-1α/CCL3; describes several diseases associated with MIP-1α/CCL3, particularly periodontitis; and delineates the potential application of MIP-1α/CCL3 as a biomarker.

In Black Africans with rheumatoid arthritis, ACPA recognize citrullinated fibrinogen and the derived peptides α36-50Cit38,42 and β60-74Cit60,72,74, like in Caucasians

Well documented in Caucasians and Asians, the diagnostic value of anti-CCP2 antibodies has been confirmed in Black African populations. However, autoantibodies to other citrullinated peptides/proteins and their fine specificities have not yet been studied. Here, we show that in Cameroonian patients, anti-citrullinated fibrinogen autoantibodies (AhFibA) are sensitive (73%) diagnostic markers for RA. We also determine that autoantibodies directed to α36-50Cit38,42 or β60-74Cit60,72,74 peptides which bear the immunodominant epitopes of citrullinated fibrin, are present in similar proportions in Black Africans and Caucasians with 25/56 (45%) and 41/56 (73%) positive RA-sera in Cameroonians, respectively. They also account for almost all the AhFibA reactivities since 38/41 (93%) AhFibA-positive sera contain anti-α36-50Cit38,42 and/or anti-β60-74Cit60,72,74 autoantibodies. Finally, HLA-DRB1 SE alleles were associated with higher titres of AhFibA and anti-β60-74Cit60,72,74 autoantibodies. In the genetic and environmental backgrounds of Black Africans, AhFibA are a hallmark of RA like in Caucasians, moreover they recognize the same fibrin epitopes.

Treatment of rheumatoid arthritis with roxithromycin: a randomized trial

BACKGROUND

High levels of antibodies to oral anaerobic bacteria have been found in the serum and synovial fluid of patients with rheumatoid arthritis (RA). Macrolide antibiotics are active against oral anaerobic bacteria. The aim of this trial was to evaluate the efficacy of roxithromycin in patients with RA who had not responded to disease-modifying antirheumatic drugs.

METHODS

This was a 6-month, randomized, double-blind, placebo-controlled trial. We treated 100 patients with active RA with either once-daily oral roxithromycin 300 mg or daily oral placebo for 6 months. The primary efficacy variable was the percentage of patients who had a 20% improvement according to the American College of Rheumatology (ACR) criteria (an ACR20 response) at 6 months. Secondary outcome measures were 50% improvement and 70% improvement according to ACR criteria (an ACR50 response and an ACR70 response, respectively).

RESULTS

A significantly greater percentage of patients treated with roxithromycin 300 mg met the ACR 20% improvement criteria (ie, achieved an ACR20 response) at 6 months compared with patients who received placebo (60% vs 34%; P = 0.009). Greater percentages of patients treated with roxithromycin 300 mg also achieved ACR50 responses (38% vs 12%; P = 0.003) and ACR70 responses (18% vs 2%; P = 0.008) compared with patients who received placebo. Roxithromycin was well tolerated, with an overall safety profile similar to that of placebo.

CONCLUSION

In patients with active RA, treatment with roxithromycin significantly improved the signs and symptoms of RA.

[Pathogenesis of parodontitis in rheumatic diseases]

Inflammatory periodontal disease (PD) is a common disease worldwide that has a primarily bacterial aetiology and is characterized by dysregulation of the host inflammatory response. The degree of inflammation varies among individuals with PD independently of the degree of bacterial infection, suggesting that alteration of the immune function may substantially contribute to its extent. Factors such as smoking, education, and body mass index (BMI) are discussed as potential risk factors for PD. Most PD patients respond to bacterial invaders by mobilizing their defensive cells and releasing cytokines such as interleukin (IL)-1beta, tumour necrosis factor (TNF)-alpha, and IL-6, which ultimately causes tissue destruction by stimulating the production of collagenolytic enzymes, such matrix metalloproteinases. Recently, there has been growing evidence suggesting an association between PD and the increased risk of systemic diseases, such ateriosclerosis, diabetes mellitus, stroke, and rheumatoid arthritis (RA). PD and rheumatologic diseases such as RA share many pathological aspects and immunological findings.

Efficacy of roxithromycin in adult patients with rheumatoid arthritis who had not received disease-modifying antirheumatic drugs: a 3-month, randomized, double-blind, placebo-controlled trial

BACKGROUND

It has been reported that antibodies to oral anaerobic bacteria are elevated in the serum and synovial fluids of patients with rheumatoid arthritis. Macrolide antibiotics are active against oral anaerobic bacteria.

OBJECTIVE

The aim of this work was to evaluate the clinical efficacy of roxithromycin in patients with early seropositive rheumatoid arthritis.

METHODS

This was a double-blind trial. We enrolled adult patients with early rheumatoid arthritis who had not previously received disease-modifying antirheumatic drugs and randomized them to receive either once-daily oral roxithromycin 300 mg or once-daily oral placebo for 3 months. The primary efficacy variable was the percentage of patients who had a 20% improvement according to the American College of Rheumatology (ACR) criteria (an ACR 20 response) at 3 months. Secondary outcome measures were 50% improvement and 70% improvement according to ACR criteria (an ACR 50 response and an ACR 70 response, respectively). The 28-joint disease activity score (DAS28) was also calculated. Clinical remission was defined as DAS28 score <2.6, and a low level of disease activity was defined as DAS28 score <3.2 but > or =2.6. Adverse event data (eg, example, type, severity, time of occurrence, time to resolution) were obtained from physical examinations and patient self-reporting.

RESULTS

The roxithromycin group had 16 patients (mean [SD] age, 45 [4] years; 11 women, 5 men; all white). The placebo group had 15 patients (mean [SD] age, 42 [5] years; 10 women, 5 men; all white). A significantly greater percentage of patients treated with 300 mg of roxithromycin experienced an ACR 20 re- sponse at 3 months, compared with those who received placebo (75% [n = 12] vs 20% [n = 3]; P = 0.002). Greater percentages of patients treated with 300 mg of roxithromycin also achieved ACR 50 responses (56% [n = 9] vs 7% [n = 1]; P = 0.003) and ACR 70 responses (44% [n = 7] vs 0%; P = 0.004) compared with patients who received placebo. At month 3, DAS28 response rates were significantly greater with once-daily roxithromycin 300 mg than with once-daily placebo (P < 0.001). Adverse events were reported for 11 patients (69%) in the roxithromycin group and 7 patients (47%) in the placebo group. The most common adverse events (>5%) were nausea, abdominal pain, headache, and dry mouth. There were no dose-limiting toxic effects. One participant in the roxithromycin group withdrew from the study because of severe emesis; two withdrew from the placebo group because of lack of efficacy.

CONCLUSIONS

In these adult patients with rheumatoid arthritis, 3-month treatment with roxithromycin significantly improved the signs and symptoms of rheumatoid arthritis and was generally well tolerated. Future studies should investigate the relationship between disease activity and serum or joint antibodies to anaerobic bacteria.

Infections and autoimmunity--friends or foes?

Autoimmunity can be triggered by many environmental factors, among which infectious agents are pivotal. Here, we summarize current knowledge of the relationship between infection and autoimmunity. An autoimmune disease can be induced or triggered by infectious agents, which can also determine its clinical manifestations. Most infectious agents, such as viruses, bacteria and parasites, can induce autoimmunity via different mechanisms. In many cases, it is not a single infection but rather the 'burden of infections' from childhood that is responsible for the induction of autoimmunity. The development of an autoimmune disease after infection tends to occur in genetically susceptible individuals. By contrast, some infections can protect individuals from specific autoimmune diseases (i.e. the hygiene hypothesis).

Rheumatoid arthritis is linked to oral bacteria: etiological association

The purpose of this review is to evaluate the association between rheumatoid arthritis (RA) and periodontopathic bacteria. Clinical studies of RA and periodontal disease have provided evidence for a significant association between the two disorders. Patients with long-standing active RA have a substantially increased frequency of periodontal disease compared with that among healthy subjects. High levels of oral anaerobic bacterial antibodies have been found in the serum and synovial fluid of RA patients. Porphyromonas gingivalis, Tannerella forsythensis, and Prevotella intermedia have been identified in RA synovial fluid. Ornidazole, levofloxacin, and clarithromycin are used in the treatment of infections caused by anaerobic bacteria. These antibiotics have been shown to be effective against RA. The evidence in this review indicates that oral bacteria directly associate with etiopathogenesis of RA.

Detection of arthritis-susceptibility loci, including Ncf1, and variable effects of the major histocompatibility complex region depending on genetic background in rats

OBJECTIVE

To characterize the arthritis-modulating effects of 3 non-major histocompatibility complex (MHC) quantitative trait loci (QTLs) in rat experimental arthritis in the disease-resistant E3 strain, and to investigate the disease-modulating effects of the MHC region (RT1) in various genetic backgrounds.

METHODS

A congenic fragment containing Ncf1 along with congenic fragments containing the strongest remaining loci, Pia5/Cia3 and Pia7/Cia13 on chromosome 4, were transferred from the arthritis-susceptible DA strain into the background of the completely resistant E3 strain. The arthritis-regulatory potential of the transferred alleles was evaluated by comparing the susceptibility to experimental arthritis in congenic rats with that in E3 rats. The RT1(u) haplotype from the E3 strain was transferred into the susceptible DA strain (RT1(av1)), and various F(1) and F(2) hybrids were generated to assess the effects of RT1 on arthritis susceptibility.

RESULTS

The DA allele of Ncf1 did not break the arthritis resistance of the E3 rats, although it led to enhanced autoimmune B cell responses, as indicated by significantly elevated levels of anticollagen antibodies in congenic rats. Introgressing Pia5 and Pia7 loci on chromosome 4 broke the resistance to arthritis, and the MHC locus on chromosome 20 in DA rats enhanced arthritis when RT1 interacted with E3 genes.

CONCLUSION

The findings in these congenic lines confirm the existence of 3 major QTLs that regulate the severity of arthritis and are sufficient to induce the transformation of a completely arthritis-resistant rat strain into an arthritis-susceptible strain. This study also reveals a dramatic difference in the arthritis-regulatory potential of the rat MHC depending on genetic background, suggesting that strong epistatic interactions occur between MHC and non-MHC genes.

Effects of clarithromycin in patients with active rheumatoid arthritis

OBJECTIVE

To evaluate the clinical efficacy, safety, and tolerability of clarithromycin in patients with rheumatoid arthritis.

RESEARCH DESIGN AND METHODS

This was a 6-month, monocenter, randomized, double-blind, placebo-controlled study. A total of 81 patients with early rheumatoid arthritis were treated with either once-daily oral clarithromycin (500 mg) or daily oral placebo for 6 months.

MAIN OUTCOME MEASURES

The primary efficacy variable was the percentage of patients who had a 20% improvement according to American College of Rheumatology (ACR) criteria (an ACR 20 response) at 6-months. Secondary outcome measures were 50% improvement and 70% improvement according to ACR criteria (an ACR 50 response and an ACR 70 response, respectively).

RESULTS

A significantly greater percentage of patients treated with 500 mg clarithromycin met the ACR 20 response at 6 months compared with patients who received placebo (59 vs. 33%; p < 0.001). Greater percentages of patients treated with 500 mg clarithromycin also achieved ACR 50 responses (34 vs. 10%; p < 0.001) and ACR 70 responses (20 vs. 3%; p = 0.003) compared with patients who received placebo, respectively. Clarithromycin was well tolerated. There were no dose-limiting toxic effects.

CONCLUSIONS

In patients with early active rheumatoid arthritis, treatment with clarithromycin significantly improved the signs and symptoms of rheumatoid arthritis. Clarithromycin has been shown to be effective against rheumatoid arthritis.

Levofloxacin treatment in patients with rheumatoid arthritis receiving methotrexate

BACKGROUND

Sulfasalazine and tetracyclines are effective against rheumatoid arthritis (RA). Levofloxacin, the bacteriologically active isomer of ofloxacin, is used in the treatment of infections caused by periodontopathic bacteria and facultative anaerobic bacteria. The aim of this study is to evaluate the clinical efficacy, safety, and tolerability of levofloxacin in patients with rheumatoid arthritis.

METHODS

In a 6-month, double-blind trial, we randomly assigned 76 patients with persistently active rheumatoid arthritis despite at least 6 months of methotrexate therapy at a stable dose of 15 to 25 mg per week to receive either levofloxacin (500 mg) or placebo orally once daily while continuing to receive methotrexate. The change from baseline to six months in the swollen-joint count and tender-joint count was the primary measure of efficacy. Secondary endpoints included pain, quality of life, duration of morning stiffness, erythrocyte sedimentation rate, C-reactive protein level, and physician's and patient's global assessments. The data were also analyzed to determine the number of patients meeting American College of Rheumatology criteria for 20, 50, and 70% improvement.

RESULTS

The levofloxacin plus methotrexate was associated with the greatest reduction in the number of swollen or tender joints (P < 0.001). The levofloxacin plus methotrexate group also had significant improvement in many of the secondary outcome measures (P < 0.001). Levofloxacin was well tolerated. There were no dose-limiting toxic effects.

CONCLUSION

In patients with active rheumatoid arthritis who received methotrexate, treatment with levofloxacin significantly improved the signs and symptoms of rheumatoid arthritis.

Serum antibodies to oral anaerobic bacteria in patients with rheumatoid arthritis

BACKGROUND

This study was conducted to determine the component that causes the disease in rheumatoid arthritis (RA), which shows great resemblance to periodontitis in a pathologic context.

MATERIALS AND METHODS

Within this study, the pathogen-specific IgG levels formed against Porphyromonas gingivalis FDC 381, Prevotella melaninogenica ATCC 25845, Actinobacillus actinomycetemcomitans Y4, Bacteroides forsythus ATCC 43047, and Prevotella intermedia 25611 oral bacteria were researched from the blood serum samples of 30 RA patients and 20 healthy controls with the enzyme-linked immunosorbent assay (ELISA) method.

RESULTS

The IgG levels of P gingivalis, P intermedia, P melaninogenica, and B forsythus were found to be significantly higher in RA patients when compared with those of the controls. Of the other bacteria antibodies, A actinomycetemcomitans was not found at greater levels in RA serum samples in comparison with the healthy samples.

CONCLUSION

The antibodies formed against P gingivalis, P intermedia, P melaninogenica, and B forsythus could be important to the etiopathogenesis of RA.

Host genetic determinants in hepatitis C virus infection

In addition to viral and environmental/behavioural factors, host genetic diversity is believed to contribute to the spectrum of clinical outcomes in hepatitis C virus (HCV) infection. This paper reviews the literature with respect to studies of host genetic determinants of HCV outcome and attempts to highlight trends and synthesise findings. With respect to the susceptibility to HCV infection, several studies have replicated associations of the HLA class II alleles DQB1(*)0301 and DRB1(*)11 with self-limiting infection predominantly in Caucasian populations. Meta-analyses yielded summary estimates of 3.0 (95% CI: 1.8-4.8) and 2.5 (95% CI: 1.7-3.7) for the effects of DQB1(*)0301 and DRB1(*)11 on self-limiting HCV, respectively. Studies of genetics and the response to interferon-based therapies have largely concerned single-nucleotide polymorphisms and have been inconsistent. Regarding studies of genetics and the progression of HCV-related disease, there is a trend with DRB1(*)11 alleles and less severe disease. Studies of extrahepatic manifestations of chronic HCV have shown an association between DQB1(*)11 and DR3 with the formation of cryoglobulins. Some important initial observations have been made with respect to genetic determinants of HCV outcome. Replication studies are needed for many of these associations, as well as biological data on the function of many of these polymorphisms.

Heavy cigarette smoking is strongly associated with rheumatoid arthritis (RA), particularly in patients without a family history of RA

OBJECTIVES

To investigate the potential relation between cumulative exposure to cigarette smoking in patients with or without rheumatoid arthritis (RA) and a positive family history of the disease.

METHODS

239 outpatient based patients with RA were compared with 239 controls matched for age, sex, and social class. A detailed smoking history was recorded and expressed as pack years smoked. Conditional logistic regression was used to calculate the association between RA and pack years smoked. The patients with RA were also interviewed about a family history of disease and recorded as positive if a first or second degree relative had RA. The smoking history at the time of the study of the patients with RA with or without a family history of the disease was compared directly with that of their respective controls. Patients with RA with or without a family history of the disease were also compared retrospectively for current smoking at the time of disease onset.

RESULTS

An increasing association between increased pack years smoked and RA was found. There was a striking association between heavy cigarette smoking and RA. A history for 41-50 pack years smoked was associated with RA (odds ratio (OR) 13.54, 95% confidence interval (95% CI) 2.89 to 63.38; p<0.001). The association between ever having smoked and RA was modest (OR 1.81, CI 1.22 to 2.19; p=0.002). Furthermore, cigarette smoking in the patients with RA without a positive family history of RA was more prevalent than in the patients with a positive family history of RA for ever having smoked (72% v 54%; p=0.006), the number of pack years smoked (median 25.0 v 4.0; p<0.001), and for smoking at the time of disease onset (58% v 39%; p=0.003).

CONCLUSIONS

Heavy cigarette smoking, but not smoking itself, is strongly associated with RA requiring hospital follow up and is markedly more prevalent in patients with RA without a family history of RA.

Only high disease activity and positive rheumatoid factor indicate poor prognosis in patients with early rheumatoid arthritis treated with "sawtooth" strategy

OBJECTIVES

To investigate the prognostic significance of clinical and genetic markers on the outcome of patients with recent-onset rheumatoid arthritis (RA) treated actively with slow acting antirheumatic drugs (SAARDs).

METHODS

A total of 142 consecutive patients with early RA (median disease duration of 7 months) were treated according to the "sawtooth" strategy and prospectively followed up for an average of 6.2 years. Several clinical parameters at start as well as genetic markers were related to the functional outcome (ARA Functional class and HAQ disability score) and radiographic joint damage (Larsen's score) at the latest visit.

RESULTS

In logistic regression analysis only Mallya score (including morning stiffness, pain scale, grip strength, Ritchie's articular index, haemoglobin, and erythrocyte sedimentation rate) at baseline, and Mallya score and rheumatoid factor (RF) positivity at one year were found to be of significance with respect to the radiographic outcome of the patients. Furthermore, at the latest visit HAQ score was related to radiographic score. At baseline the mean ages of the DR4 positive patients and the patients with RA associated DR alleles were statistically significantly lower than those without the above mentioned risk factors (44 v 49, p = 0.03 and 41 v 53, p = 0.04, respectively). However, these genetic markers had no prognostic significance on the functional or radiographic outcome of the patients.

CONCLUSION

High clinical disease activity at baseline and RF positivity especially at one year after the institution of SAARD treatment are the best predictors of poor prognosis in early RA. However, from the clinical point of view, the disease outcome of an individual patient with early RA, cannot be predicted accurately enough by present means.

Examination of HLA-DR4 as a severity marker for rheumatoid arthritis in Greek patients

OBJECTIVES

Previous reports have shown that HLA-DR4 may be a severity marker for rheumatoid arthritis (RA) in patients of northern European origin. The aim of the present study was to investigate this relation in Greek patients with RA, as RA in Greece differs from the RA described previously on clinical, serological, and immunological grounds.

METHODS

Eighty four patients were studied in whom HLA-DR typing was performed by restriction fragment length polymorphism and the subtypes of HLA-DR4 were determined by the polymerase chain reaction. The absence or presence of HLA-DR4 and its subtypes was correlated with the clinical and serological characteristics of the patients and with the side effects due to disease modifying drugs.

RESULTS

Twenty one of the 84 (25%) patients with RA were DR4+. There was no difference between the DR4+ and DR4-patients with respect to duration of disease, severity of arthritis, functional grade, and joint erosion score. The DR4+ group were more likely to have side effects due to disease modifying drugs (43%) than DR4- patients (36%), but this difference was not statistically significant. DR4-patients had more extra-articular manifestations, including Sjögren's syndrome (47 v 19%). Analysis of the DR4 subtypes showed that Dw15 was the most common variant (9/21 patients; 43%). There was no statistical difference in the clinical manifestations among patients with different DR4 subtypes. The same was also true when the clinical picture was correlated with the 'shared RA epitope' (QKRAA/QRRAA/RRRAA), which is common to all HLA-DRB1 alleles positively associated with RA.

CONCLUSIONS

These results suggest that HLA-DR4 is not a severity marker in Greek patients with RA and further indicate differences in the clinical expression of RA in Greece.

HLA-DR1 and rheumatoid arthritis in Israeli Jews: sequencing reveals that DRB1*0102 is the predominant HLA-DR1 subtype

Rheumatoid arthritis (RA) is associated with the HLA-DR4 cellular subtypes Dw4 and Dw14 in Caucasians, with Dw15 in Japanese, and possibly with HLA-DR1 in Israeli Jews. Sequencing studies in Caucasians have shown that these molecules share a common amino acid sequence in the third hypervariable region of the DR molecule (AA 67-74: LLEQRRAA or LLEQKRAA), suggesting that this sequence is primarily associated with RA. An important argument in favor of this shared-epitope hypothesis has been the reported association between DR1 and RA in Israeli Jews. However, a later report did not confirm this association, and cellular typing showed that Israeli DR1 consists of three or more subtypes, suggesting that new subtypes might be present. Since no sequencing data on Israeli HLA-DR1 genes have been reported, we sequenced the first domain (AA 10-91) of the DRB1 gene in 12 DR1-positive Israeli RA patients, 5 healthy controls and a homozygous typing cell (HTC), defining the major Jewish cellular HLA-DR1 subtype. DRB1*0102 (DR1 Dw20) was found in 8 RA patients, 3 controls and the HTC "LVA". DRB1*0101 (DR1 Dw1) was found in 4 RA patients and 2 controls. No other DR1 subtypes were encountered. In all 20 DR1 haplotypes, the DRB1*0101 or 0102 allele was associated with DQA1*0101 and DQB1*0501, being identical to the Caucasian DR1 haplotypes. Thus, at the sequence level, we found no basis for the reported extensive cellular heterogeneity of DR1 in the Israeli population.(ABSTRACT TRUNCATED AT 250 WORDS)

Novel genetic markers of rheumatoid arthritis in chilean patients, by dr serotyping and restriction fragment length polymorphism analysis

OBJECTIVE

The analysis of genetic markers of rheumatoid arthritis (RA) in a population in which the DR4 serotype is not strongly associated with the disease.

METHODS

Chilean RA patients (56 seropositive and 22 seronegative) and 141 controls were studied by serotyping. Southern blot analysis of Bam HI restriction fragment length polymorphism (RFLP) was done in genomic DNA from 46 patients with seropositive RA, 17 patients with seronegative RA, and 45 controls, using a complementary DNA probe specific for DRB1 genes.

RESULTS

The prevalence of the HLA-DR9 haplotype was strikingly higher in seropositive RA patients (21%) than in controls (3%) (Pcorr less than 0.0008, by Fisher's exact test; relative risk [RR] = 9.34). The prevalence of DR4 and DR1 haplotypes, although slightly increased, did not achieve a significant preponderance. The simultaneous presence of two Bam HI fragments (3.6 kb and 4.5 kb) was found with higher prevalence in seropositive patients (83%; RR = 9; Pcorr less than 0.00002) than in controls (36%), and seemed higher in seronegative RA patients as well (71%; RR = 4). Furthermore, its prevalence remained increased in comparisons of DR4 positive controls (36%) with DR4 positive seropositive patients (100%; RR = 67; Pcorr less than 0.0002) and DR4 positive seronegative patients (100%; RR = 36; Pcorr less than 0.006), even after excluding the DR9 positive individuals. A tendency toward higher association with DR1 seropositive RA patients (67%; RR = 12), a group with no DR4 or DR9 positive individuals, than in DR1 positive controls (14%), was also observed.

CONCLUSION

The HLA-DR9 haplotype was definitively consolidated as a very strong genetic marker exclusively for seropositive RA in Chilean patients, as suggested by our previous observations. RFLP analysis showed that the simultaneous presence of 3.6-kb and 4.5-kb Bam HI fragments constituted a better RA marker than did any of the heretofore studied haplotypes. These fragments together would be linked to RA independently of the DR1, DR4, and DR9 haplotypes. The overall evidence indicates that Chilean seropositive RA patients display a genetic background that is different from that underlying RA susceptibility in other populations and suggests the existence of common, as well as distinct, genetic elements predisposing to seronegative and seropositive RA.

Association of HLA-DR4 with a more progressive disease course in patients with rheumatoid arthritis. Results of a followup study

The association between HLA-DR antigens and rheumatoid arthritis (RA) was investigated in a well-characterized cohort of RA patients who were followed from the beginning of the disease (mean followup 6 years). The frequencies of HLA-DR antigens in patients with possible or probable RA (n = 49) were similar to those in controls. In patients with definite RA (n = 134), the frequencies of DR1, DR4, and DRw53 were increased, whereas the frequencies of DR2, DR3, DRw6, DRw13, and DRw52 were decreased, compared with controls. Comparison of HLA-DR frequencies in patients with definite RA subclassified according to the severity of the disease at the end of the followup period revealed a difference only in the frequency of DR4, which was increased in patients with progressive RA (59.2%) compared with those who had mild RA (34.8%). Further analysis showed that, compared with DR4-negative RA patients, DR4-positive patients had more swollen joints, higher scores on the Ritchie articular index, the Health Assessment Questionnaire, and the Steinbrocker functional classification, more radiologic abnormalities, and more use of second-line drugs. Also, the rate of progression of radiologic abnormalities, functional classification, and use of second-line drugs was higher in DR4-positive patients. We conclude that DR4 is associated with a more severe disease course, and is a prognostic marker in early RA.

Weak association between HLA-DR4 and rheumatoid arthritis in Chilean patients

Evidence has suggested a genetic link between the HLA-DR4 phenotype and rheumatoid arthritis (RA), particularly in its seropositive form. Such an association varies among different ethnic groups and remains controversial for seronegative patients. Data obtained for a group of 64 Chilean patients with RA (46 seropositive, 18 seronegative), as defined by the 1987 criteria of the American Rheumatism Association, and for 76 controls are reported here. The prevalence of HLA-DR4 and DR9 was significantly increased in the group of patients considered as a whole. The prevalence of HLA-DR4 was not significantly higher, however, when seronegative and seropositive patients were separately compared with controls. Also, it did not correlate with the severity of the disease within each subgroup of patients. On the other hand, HLA-DR9 showed a highly significant difference, not previously described, only for the seropositive patients in comparison with controls. The prevalence of DQ specificities showed no relevant differences among the groups. The HLA-DR4 serotype, therefore, is a weak marker for RA and does not differentiate any subgroup of patients in the Chilean group studied. This new finding, indicating an association between RA and the DR9 antigen, may be explained by the suggestion that susceptibility epitopes are shared among different DR molecules. This hypothesis might also account for the variation in the association of DR4 with RA.

Immunogenetic heterogeneity of seronegative rheumatoid arthritis and the antiperinuclear factor

HLA typing was carried out in 132 patients with rheumatoid arthritis (RA) with long term follow up, and special attention was focused on rheumatoid factor negative patients. The patients were divided into four groups: 55 patients with a seropositive RA and a positive antiperinuclear factor (group A); 39 seropositive patients but a negative antiperinuclear factor (group B); 14 patients consistently seronegative for 3-28 years (mean 11.8 years) but positive for antiperinuclear factor (group C); patients consistently negative for 3-28 years (mean 11.8) and also negative for antiperinuclear factor (group D). The prevalence of HLA-DR4 was 31/55 (56%), 29/39 (74%), 10/14 (71%), and 9/24 (37%) for groups A, B, C, and D respectively, and in all groups was significantly higher than in 277 healthy controls (55/277, 20%). No significant difference was found between seropositive (groups A and B) and seronegative (groups C and D) patients, but groups A, B, and C had higher prevalences than group D. It is concluded that in seronegative RA HLA-DR4 is preferentially associated with the antiperinuclear factor positive group.

DR4 prevalence related to the age at disease onset in female patients with rheumatoid arthritis

The prevalence of HLA-DR4 in relation to age at disease onset was calculated in 226 consecutive female patients with definite or classical rheumatoid arthritis (RA). A slight increase in the prevalence of DR4 with age at RA onset was found. This appeared to be due to the low percentage of rheumatoid factor (RF) positivity in the youngest age groups; the DR4 prevalence in the RF positive patients was constant for all decades--that is, approximately 60%. A previously reported declining trend of DR4 prevalence in women with RA in relation to age of RA onset may be due to the disease heterogeneity of the patients included in that study.

Prediction of erosiveness and rate of development of new erosions in early rheumatoid arthritis

Fifty eight patients suffering from a recent onset of rheumatoid arthritis (RA) were studied. Fifty six patients were followed up for 24 months and two for 18 months. Erosions were detected in 17 patients at the onset and at the end of the follow up period the number of patients with erosions was 44. The erosiveness in the joint groups studied was as follows: metatarsophalangeal (MTP) (36 patients), metacarpophalangeal (MCP) (22), proximal interphalangeal (PIP) (21), interphalangeal (IP) joints of first toes and wrists (13), elbows and knees (two), and shoulders, ankles, and hips (one). Erosiveness in the feet was twice that in the fingers, and the erosions in the feet appeared at an earlier phase of disease. Destructions favoured the dominant hand. Swelling in the PIP joints appeared to be a better predictor of erosiveness than joint tenderness. The number of joints to become eroded was significantly increased in the patients with flexor tenosynovitis in the hands. Erythrocyte sedimentation rate (ESR) was more closely related to progression of joint damage than C reactive protein (CRP) or haemoglobin. The rate of development of new erosions was the same in seronegative and seropositive patients. In addition, HLA-DR4 allele did not correlate either with seropositivity or with erosiveness. Adequate antirheumatic drug treatment (gold in most instances) was not able to restrain the erosive process despite decreased rheumatoid disease activity.

Associations of HLA-DR4 with rheumatoid factor and radiographic severity in rheumatoid arthritis

Possible associations between HLA-DR4 and laboratory, radiographic, joint count, functional, and demographic measures of clinical status were analyzed in 154 white patients with rheumatoid arthritis. Overall, 65 percent of the patients were HLA-DR4 positive, similar to other series. HLA-DR4 was associated significantly with the presence of rheumatoid factor and more severe radiographic changes. HLA-DR4 was not associated with significant differences in demographic, joint count, or functional measures of clinical status. HLA-DR1 was not associated significantly with differences in the presence of rheumatoid factor, radiographic changes, or other measures of clinical status. Selective associations of HLA-DR4 with rheumatoid factor and radiographic scores were more marked in men than in women. Patients who were putatively homozygous for HLA-DR4 were all seropositive and had more severe radiographic changes than patients who were heterozygous for HLA-DR4.

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.

Rheumatoid arthritis with pleural effusion includes a subgroup with autoimmune features and HLA-B8, Dw3 association

Twenty-eight patients with rheumatoid pleural effusion were investigated to examine the frequency of HLA antigens as compared with 56 rheumatoid arthritis (RA) patients without this intrathoracic manifestation of RA and with 283 healthy controls. HLA-B8 was strongly associated with the presence of pleural effusion (PE) in RA patients. A high prevalence (71%) of B8/Dw3 was found among male RA patients of the PE group in whom the joint disease had begun at an age over 50 years and who also had besides pleuritis other intrathoracic manifestations of RA associated with high rheumatoid factor titres and low complement (C4) levels in sera. Actually, the HLA-B8 association was not seen in the rest of the PE group. The finding may be related to the heterogeneity of RA, a male subgroup of the disease being characterized by multiple intrathoracic manifestations and genetically associated with the large group of autoimmune disorders, such as SLE, characterized by high prevalences of HLA-B8 and D(R)3.

Diffuse interstitial lung disease in rheumatoid arthritis. Views on immunological and HLA findings

Immunological parameters including HLA typing were studied in 32 patients with rheumatoid arthritis (RA) associated diffuse interstitial lung disease (DILD) and in 32 age- and sex-matched RA control patients. The male RA patient group with DILD also included patients with other intrathoracic manifestations and had a higher prevalence of HLA-B8 and Dw3 than did healthy controls, thus agreeing with our earlier results that RA patients with this antigen combination are prone to multiple intrathoracic complications. Patients with DILD had higher titres of rheumatoid factor (RF) and lower complement (C4) levels than matched RA controls. The RF titre was in inverse correlation with C3 and C4 levels, suggesting that RF immune complexes may also promote rheumatoid lung disease via activation of the classical pathway of complement.

HLA-DR4 as a predictor of outcome three years after onset of rheumatoid arthritis

Data from 59 patients with early rheumatoid arthritis were analysed to determine the predictive value of the possession of HLA-DR4 for disease severity and functional outcome at 3 years after disease onset. The previously reported association of that antigen with seropositive disease was confirmed. Conversely, however, there was no evidence that functional outcome was worse in the HLA-DR4 positive group as measured by the Stanford Health Assessment Questionnaire. The mean articular index was lower in the HLA-DR4 group which also had a smaller proportion with limited wrist extension. In addition, both patient and physicians' global assessment of disease status were better in the HLA-DR4 group. It is concluded that HLA-DR4 is not a useful predictor of poor outcome at 3 years.

Etiology of rheumatoid arthritis

Definite genetic associations with immunological cooperative HLA-D(R) antigens have been demonstrated for rheumatoid arthritis (RA). Microbial etiology has not been proven, but some hope for the supporters of this view is still given by small viruses, plasmids of enteric bacteria or perhaps oncogen-like DNA-sequences. Yet, electrophoretical analysis of membrane proteins or surface glycoproteins of RA synovial cells does not show any differences compared to reference cells. Autoimmunity to several tissue elements has been demonstrated, but most of it is of secondary nature. Antigenicities of type II and III collagens are probably only contributory factors for HLA-DR4 positive individuals. Proteoglycans or minor cartilage collagens have not been extensively studied, so far. Endocrine, dietary or psychological influences might be triggering events for otherwise 'preloaded' individuals.

IgG heavy chain (Gm) allotypes in rheumatoid arthritis and in healthy individuals seropositive for IgM-rheumatoid factor

The frequencies of Gm allotypes a, x, f, b, g and n have been investigated in classical seropositive rheumatoid arthritis (RA), erosive definite seronegative RA, non-erosive definite RA and in healthy individuals with serum IgM-RF. No differences in the frequencies of these Gm allotypes were found between patients and healthy controls. It is concluded that any possible putative genes outside the HLA region involved in RA are most likely unrelated to the genes coding for the constant regions of IgG heavy (gamma) chains.

The prevalence of HLA-DR4 and HLA-DR3 in healthy persons with rheumatoid factor

The frequency of the HLA antigen DR4 has been determined in healthy individuals with serum IgM RF. HLA DR4 was found in 11.6% of these persons as compared with 27% in healthy controls. Thus, no association between IgM RF and HLA-DR4 could be found in this material of healthy individuals. HLA-DR3 was found in 35% of healthy RF-positive persons, which was no different from the 30% prevalence among healthy controls. HLA-DR3 did not seem to be associated with high immune responsiveness of RF in RF-positive individuals.

HLA antigens and seronegative rheumatoid arthritis

HLA antigens and clinical features in a series of 46 Caucasian patients (40 females, 6 males) and definite repeatedly seronegative rheumatoid arthritis (RA) of more than two years' duration (mean 11.6 years) were compared with those in 77 seropositive RA patients and 110 controls of the same ethnic and geographic origin. Seronegative RA appeared to be less often erosive than seropositive RA, and seronegative patients had fewer extra-articular features. The frequency of the HLA antigen DR1 was raised in seronegative patients as compared with controls (p = 0.006, relative risk = 3) and with seropositive patients (p less than 0.05). HLA-DR4 was slightly increased in seronegative patients compared with controls (p less than 0.05) but was clearly less so than in seropositive patients (p less than 0.005). Early onset of disease was very significantly associated with HLA-DR1 in seronegative patients (p = 0.007), whereas HLA-DR4 was present more frequently in seropositive patients with onset prior to age 35 (p less than 0.05). No correlation between HLA antigens and intolerance to drugs was found in seronegative patients, whereas in seropositive patients side effects to gold salts were associated with DR3. These results suggest that seropositive and seronegative RA have distinct HLA-DR associations, especially in disease of early onset, in addition to well established clinical differences.

Prognostic factors and diagnostic criteria in early rheumatoid arthritis

The purpose of the present undertaking was to investigate prognosis of patients with non-specific or rheumatoid arthritis and to study the value of different diagnostic criteria for rheumatoid arthritis (RA) at the beginning of the disease. During the years 1973-75, a total of 442 patients with recent (less than or equal to 6 months) arthritis were studied at the Rheumatism Foundation Hospital, Heinola, Finland. In 1982 the outcome of the 200 patients with the diagnosis of RA or non-specific arthritis was established. Their ages at the time of the first hospitalization were 16-77 years, mean 41. There were 63 men and 137 women. The follow-up period was 6-9 years, mean 7.6. The outcome was measured by joint score, function score, the sum of ESR and CRP, X-ray index, outcome index, which was composed of the preceding ones, ESR, and CRP. The outcome was poor in half of the patients. Ninety-eight signs and symptoms registered at the first hospitalization were compared with the seven facets of outcome using Pearson's correlation coefficient r. The significances of the correlation coefficients were tested by Student's t-test. From 10 to 39 variables correlated highly significantly (p less than 0.001) with the measures of outcome; however, most of the variables had only moderate correlations. At best 14 variables showed 0.40 less than r less than 0.58 when correlated with the outcome index. In conclusion, at the onset of an arthritic disease symmetrical polyarthritis in peripheral joints, serum rheumatoid factor, X-ray changes, morning stiffness, high ESR, and old age correlated best with a destructive joint disease. Plasma proteins as indices of non-specific inflammation mattered less. The relationships between 22 entry variables and the seven facets of prognosis were further evaluated by means of stepwise multiple regression analysis. The results were essentially the same as reached above. One or two variables, most often the number of diseased peripheral joints and serum Waaler-Rose test, always explained the variance better than the number of ARA criteria alone. To study the value of the diagnostic criteria, diagnosis of the patients was made in the following three ways: RA with five or more erosive joints (N = 78), RF-positive and erosive RA (N = 93), RF-positive and nonerosive or RF-negative and erosive RA (N = 125). The patients outside each of the diagnostic groups formed the corresponding control groups.(ABSTRACT TRUNCATED AT 400 WORDS)

HLA antigens in rheumatoid arthritis patients with and without a family history of polyarthritis

The HLA antigens, A, B and DR, were studied in 141 patients with erosive, seropositive rheumatoid arthritis (RA). The frequency of the B27 antigen was significantly increased among patients with a family history of symmetrical polyarthritis compared with blood donor controls (p less than 0.001) and with patients without a family history of polyarthritis (p less than 0.005). The frequency of DR4 was significantly (p less than 0.001) increased among the RA patients, but there was no significant association between DR4 and a family history of polyarthritis.

HLA haplotypes in multiple case families with rheumatoid arthritis

In 9 families of which at least two members were affected by rheumatoid arthritis (RA), no specific combination of HLA genes, i.e., HLA haplotype was found to be associated with transmission of disease susceptibility. The results suggested an important role of HLA-DR4 in the etiology of RA, irrespective of other HLA markers. In addition, it may be concluded that genetic markers other than DR4 may act together with this HLA antigen in determining which individuals are at risk of developing this rheumatic disorder.

A study of IgM rheumatoid factors in a middle-aged population of Northern Norway

A random selection of 8807 blood samples was analysed for the presence of IgM rheumatoid factor (RF). The sera were obtained from an epidemiological survey of rheumatoid arthritis in a middle-aged population of Northern-Norway. The prevalence of IgM-RF was 1.36% for the total population, but a prevalence of IgM RF in healthy individuals between 0.48-0.49% was found with no significant difference between males and females. The majority of RF positive sera were low titred. Only 11.4% of the persons possessing serum IgM RF suffered from classical or definite rheumatoid arthritis. Eighty-one per cent of the IgM RF positive individuals converted to seronegativity in the course of 3.5 years.

Strong association of rheumatoid arthritis with the presence of a polymorphic Ia epitope defined by a monoclonal antibody: comparison with the allodeterminant DR4

Among individuals with rheumatoid arthritis the presence of the polymorphic Ia antigen epitope detected by the monoclonal antibody 109d6 is more strongly correlated with disease susceptibility than are other specificities, such as HLA DR4, DRw53 (MT3) or the antigenic determinant, defined by the monoclonal antibody 17-3-3S. The cells of 93% of Caucasian and Hispanic patients react with the 109d6 reagent. As was the case in normal individuals, all DR4-positive patients express the 109d6 determinant; however, 26% of those with rheumatoid arthritis have the epitope recognized by antibody 109d6, but lack the specificity DR4. Of these, one-third expresses only HLA DR1 and DQw1 (MT1, MB1) determinants. Studies of family members reveal that here the determinants 109d6, DR1, and DQw1 are encoded by the same unusual haplotype. In certain other individuals with rheumatoid arthritis who express DR4, DRw53, and the 109d6 determinants, family studies show that the 109d6 epitope is encoded not only by the haplotype specifying DR4 but also by the opposite haplotype that does not bear the genes for DR4. This suggests that homozygosity for certain Ia epitopes is relevant to determining the disease-susceptibility state. These studies emphasize the utility of monoclonal antibodies as reagents for the recognition of Ia epitopes that are more closely involved in the determination of disease susceptibility than are allomorphic molecules detected by conventional typing alloantisera.