Association of SLC11A1 (NRAMP1) with persistent oligoarticular and polyarticular rheumatoid factor–negative juvenile idiopathic arthritis in Finnish patients: Haplotype analysis in Finnish families

Objective

The SLC11A1 (formerly called NRAMP1) gene is important in natural resistance to a variety of intracellular infections mediated by macrophages and has been proposed as a candidate gene for autoimmune disease susceptibility. The aim of this study was to examine susceptibility in Finnish patients with persistent oligoarticular and polyarticular rheumatoid factor (RF)–negative juvenile idiopathic arthritis (JIA) due to the presence of the SLC11A1 locus on chromosome 2.

Methods

A total of 234 Finnish JIA nuclear families and 639 elderly Finnish controls without a history of JIA were evaluated for association with JIA at 3 intragenic single‐nucleotide polymorphisms: an intragenic insertion/deletion, a promoter microsatellite (NRAMP1), and a 3′ microsatellite (D2S1471).

Results

Analysis of marker haplotypes demonstrated a strong association of Finnish JIA with 6‐marker, 4‐marker, and 2‐marker haplotypes. Most impressively, 1 of the 6‐marker haplotypes showed an odds ratio (OR) of 4.0 (95% confidence interval [95% CI] 2.6–6.2) in all JIA patients, 3.5 (95% CI 1.9–6.5) in those with persistent oligoarticular JIA, and 4.1 (95% CI 2.5–6.7) in those with polyarticular RF‐negative JIA. Stratification of the haplotype data suggested that susceptibility to JIA in the haplotype spanning the SLC11A1 locus is independent (P < 0.01) of an association with a DRB1 JIA shared epitope (DRB1*JIASE) that includes well‐characterized strong susceptibility to DRB1*08 and *11 alleles. This SLC11A1 haplotype also had an additive effect with DRB1*JIASE in those with polyarticular, but not those with persistent oligoarticular, disease (P = 0.06, OR 2.9 [95% CI 0.9–9.2] versus P = 0.5, OR 1.6 [95% CI 0.4–6.0]).

Conclusion

Taken together, these data provide support for the existence of a locus at or near SLC11A1 that is a strong susceptibility factor for JIA in Finnish patients.

     

HLA haplotype analysis in Finnish patients with rheumatoid arthritis

OBJECTIVE: To further characterize the HLA gene products that play an important role in the pathogenesis of rheumatoid arthritis (RA). METHODS: One hundred thirty-four haplotypes from 67 Finnish RA patients and 77 control haplotypes were analyzed for HLA-DRB1 loci, associated alleles of the HLA-DQB1 locus, alleles of the type 2 transporter-associated antigen processing (TAP2) genes, and HLA-B27. In addition, a panel of microsatellite markers within the HLA class I and class III regions was studied. RESULTS: The frequency of HLA-DRB1*04 in the haplotypes of RA patients was found to be 34% (45 of 134) compared with 14% (10 of 72) in control haplotypes (P = 0.004). The frequency of HLA-DRB1*13 was decreased in RA haplotypes (4%, or 5 of 134) in contrast to control haplotypes (24%, or 17 of 72) (P = 0.000031). The decrease in DRB1*13 was not secondary to the increase in DRB1*04, since it was also found among DRB1*04-negative haplotypes (P < 0.001). The DRB1*13-associated DQB1*0604 allele was similarly decreased in RA haplotypes (P = 0.025). The TAP2I allele of I/J dimorphism was increased in RA patients (85%, or 114 of 134) as compared with controls (69%, or 49 of 71) (P = 0.011). Of the tumor necrosis factor (TNF) microsatellite alleles, TNFa6 and TNFb5 were found to be increased in RA haplotypes (for a6 27% versus 5% in controls [P = 0.00043], and for b5 43% versus 26% in controls [P = 0.037]). CONCLUSION: Both protection-associated and susceptibility-associated alleles can be found among HLA class II genes, and the results suggest that loci outside DR/DQ may contribute to the pathogenesis of RA.     

Biologic similarities based on age at onset in oligoarticular and polyarticular subtypes of juvenile idiopathic arthritis

Objective

To explore biologic correlates to age at onset in patients with juvenile idiopathic arthritis (JIA) using peripheral blood mononuclear cell (PBMC) gene expression analysis.

Methods

PBMCs were isolated from 56 healthy controls and 104 patients with recent‐onset JIA (39 with persistent oligoarticular JIA, 45 with rheumatoid factor–negative polyarticular JIA, and 20 with systemic JIA). RNA was amplified and labeled using NuGEN Ovation, and gene expression was assessed with Affymetrix HG‐U133 Plus 2.0 GeneChips.

Results

A total of 832 probe sets revealed gene expression differences (false discovery rate 5%) in PBMCs from children with oligoarticular JIA whose disease began before age 6 years (early‐onset disease) compared with those whose disease began at or after age 6 years (late‐onset disease). In patients with early‐onset disease, there was greater expression of genes related to B cells and less expression of genes related to cells of the myeloid lineage. Support vector machine analyses identified samples from patients with early‐ or late‐onset oligoarticular JIA (with 97% accuracy) or from patients with early‐ or late‐onset polyarticular JIA (with 89% accuracy), but not from patients with systemic JIA or healthy controls. Principal components analysis showed that age at onset was the major classifier of samples from patients with oligoarticular JIA and patients with polyarticular JIA.

Conclusion

PBMC gene expression analysis reveals biologic differences between patients with early‐and late‐onset JIA, independent of classification based on the number of joints involved. These data suggest that age at onset may be an important parameter to consider in JIA classification. Furthermore, pathologic mechanisms may vary with age at onset, and understanding these processes may lead to improved treatment of JIA.

     

TNF-alpha promoter gene polymorphisms in Spanish children with persistent oligoarticular and systemic-onset juvenile idiopathic arthritis

OBJECTIVE: To explore the possible association/s of the first reported tumour necrosis factor (TNF-alphaTNF-) alpha promoter gene polymorphisms -308, -238, -376 and -163 (G-->A) with systemic (SoJIA) and oligoarticular subtypes of juvenile idiopathic arthritis (JIA); and to test the association between these polymorphisms and the class I/class II HLA alleles in our population. METHODS: The patient group comprised 29 oligoarticular and 26 systemic Caucasian Spanish children with JIA; 68 healthy volunteers from the same ethnic group and geographical region served as controls. HLA alleles were determined using low-resolution polymerase chain reaction (PCR). TNF-alpha promoter gene polymorphisms were screened using PCR denaturing gradient gel electrophoresis (PCR-DGGE), followed, if positive, by restriction fragment length polymorphism (RFLP) analysis for identification. RESULTS: No statistical association was found between the four polymorphisms studied and JIA. However, the -308 G-->A polymorphism (TNF A2) tended to be more frequent in patients with SoJIA than in the oligoarticular group. TNF A2 was strongly associated with the extended haplotype A1B8DR3 (p = 0.003), and the tandem polymorphism -238/-376 in the presence of B18 and DR3. CONCLUSION: The TNF A2 allele was more frequent in SoJIA than in the oligoarticular group. TNF A2 can help to create a more inflammatory milieu in this JIA subtype, in combination with other polymorphisms involved in regulatory sequences of key molecules in the inflammatory response. The association of the -308 and -238/-376 polymorphisms with specific alleles of the HLA is reconfirmed.     

SLC11A1 (formerly NRAMP1) polymorphisms associated with multidrug-resistant tuberculosis

The solute carrier family 11 member 1 gene (SLC11A1, formerly known as NRAMP1: natural resistance-associated macrophage protein 1) is one of the host genetic factors reported to affect susceptibility to tuberculosis. The aim of this study was to determine whether SLC11A1 polymorphisms affect the incidence of multidrug-resistant tuberculosis (MDR-TB) and other clinical features of pulmonary tuberculosis. Using polymerase chain reaction and the restriction fragment-length polymorphism analyses, we investigated four previously reported SLC11A1 polymorphisms, variations in 5'(GT)n, INT4, D543N, and 3'UTR in 95 patients with pulmonary tuberculosis including 10 MDR-TB patients. Clinical information, including elapsed time for sputum culture conversion, extent of pulmonary involvement, and presence or absence of cavitary lesions, was based on a review of charts and chest radiographs. For the 10 MDR-TB patients, previous therapy and treatment compliance were also evaluated. Although the number of MDR-TB patients was small, our preliminary study showed that the variations of D543N and 3'UTR are significantly associated with the incidence of MDR-TB (odds ratio [OR]=5.03, 95% confidence interval [CI]=1.24-20.62; P=0.02), longer time to sputum culture conversion (OR=3.86, 95% CI=1.23-12.23; P=0.02), and cavity formation (OR=5.04, 95% CI=1.51-23.13; P=0.02). Three out of the 10 MDR-TB patients with good treatment compliance had at least one genetic variation in SLC11A1. These data suggested that genetic variations in SLC11A1 may affect the incidence of MDR-TB and clinical features of pulmonary tuberculosis. Further studies are needed to confirm this association with increased number of MDR-TB patients.     

Natural killer (NK) cells at inflammatory sites of patients with rheumatoid arthritis and IgM rheumatoid factor positive polyarticular juvenile rheumatoid arthritis

Summary NK cell activity and Leu 7⁺ cells were determined in mononuclear cells (MNC) from patients with rheumatoid arthritis (RA) and IgM rheumatoid factor positive polyarticular juvenile rheumatoid arthritis (JRA). NK cell activity was measured in a⁵¹Cr release assay and the Leu 7 positive cells were enumerated in indirect immunofluorescence. The mean NK cell activity ±SEM was reduced in MNC from peripheral blood (PB), synovial fluid (SF) and synovial membranes (SM's) of patients with RA, with the values of 19.5±1.4 (p<0.00003), 18.3±3.1 (p<0.009) and 2.9±0.5 (p<0.0003) respectively, compared with 26.1±1.4 in MNC from the PB of healthy controls. The mean percentages of Leu 7 positive cells in MNC from PB and SF on patients with RA were normal while the mean percentage of Leu 7⁺ cells in MNC eluted from SM's was significantly reduced as compared to that of MNC from PB of healthy controls (p<0.0006). In JRA similar results concerning NK activity and Leu 7 positive cells were found but the number of experiments was too low for statistical analysis. MNC from the SF, in contrast to that of BP and SM, had a significant cytoxicity against the Raji cell line which is a non-NK cell target.     

A case-control sleep study in children with polyarticular juvenile rheumatoid arthritis

OBJECTIVE: To investigate the relationship between clinical manifestations and sleep abnormalities in patients with juvenile rheumatoid arthritis (JRA). METHODS: Twenty-one patients with active polyarticular JRA and 20 healthy controls were enrolled consecutively. Pain and functional impairment were assessed with standardized, validated Brazilian questionnaires. Sleep evaluation was based on parent reporting of their child's sleep habits and polysomnography; subjects underwent an adaptation night in the sleep laboratory. Sleep architecture was analyzed and spectral analysis of non-rapid eye movement (REM) sleep was carried out by electroencephalography. RESULTS: Patients with JRA exhibited higher indexes of periodic leg movements (PLM; p = 0.02), isolated leg movements (LM), and arousals, as well as increases in alpha activity in non-REM sleep (all p < 0.01), in spite of similar frequency of sleep complaints in comparison to controls. Among JRA patients, greater alpha activity in non-REM sleep was observed in the participants with greater joint involvement assessed by the Escola Paulista de Medicina-Pediatric Range of Motion Scale (p = 0.03) or joint count (p = 0.02). Correlation was observed between morning stiffness and PLM and/or LM (rS = 0.75, Sr = 0.74, p < 0.001 for both), and between self-rating scores of pain and alpha activity in non-REM sleep (rS = 0.74, p < 0.001). CONCLUSION: Pain symptoms and disability are related to sleep fragmentation in patients with active polyarticular JRA.     

Optic neuritis associated with etanercept therapy in two patients with extended oligoarticular juvenile idiopathic arthritis

SIR, Two female patients treated with etanercept for extendedoligoarticular juvenile idiopathic (rheumatoid) arthritis (JIA)are presented. The first case was a 12-yr-old girl who was diagnosed at theage of 15 months with oligoarticular JIA with positive ANA.She progressed to extended oligoarticular disease, treated overthe years with NSAIDs, salazopyrin, oral methotrexate, prednisolone,intra-articular steroid injections, physiotherapy and finallyetanercept. At the age of 8 yr she developed bilateral anterior     

Prevalence of antihuman parvovirus B19 IgG antibodies in patients with refractory rheumatoid arthritis and polyarticular juvenile rheumatoid arthritis

We investigated the prevalence of antihuman parvovirus B19 immunoglobulin G (IgG) antibody in 108 Japanese patients with rheumatoid arthritis (RA) and 11 patients with polyarticular juvenile rheumatoid arthritis (JRA). Seropositivity of anti-B19 was significantly higher in patients with refractory RA (57.6%, 38/66) compared with patients with remittent RA (19.0%, 8/42; P>0.001) or age-matched controls (24.3%, 19/78; P>0.001). Patients with refractory polyarticular JRA had a significantly higher frequency of anti-B19 seropositivity (71.4%, 5/7) than age-matched controls (8.3%, 5/60; P>0.001), while none of the remittent group was positive for the antibody (0/4).     

Outcome status in children with sustained polyarticular and systemic juvenile idiopathic arthritis

SIR, Juvenile idiopathic arthritis (JIA) is the most commonrheumatic disease of childhood and an important cause of disability[1]. The reported outcome of JIA varies substantially [2–4].Traditionally, measurement of outcome has focused predominantlyon measurements of disease activity such as erythrocyte sedimentationrate (ESR) and an active joint count. Recent investigationshave highlighted the limitations of such measures [5]. Additionalfunctional outcome scales were introduced, such as the ChildhoodHealth Assessment Questionnaire (CHAQ), the Juvenile ArthritisFunctional Assessment Scale (JAFAS) and the Juvenile ArthritisFunctional Assessment Report (JAFAR). At     

A case of juvenile idiopathic polyarticular arthritis complicated by IgA deficiency in 22q11 deletion syndrome

Chronic arthritis may occur in association with antibody deficiency and chromosomal aberrations. This report presents the case of a 6-year-old girl with chromosome 22q11 deletion syndrome and chronic arthritis. The onset of arthritis occurred at 4?years of age. The chronic arthritis course has been the polyarticular type. Neither antinuclear antibody nor rheumatoid factor was detected. Serum IgA was extremely low. She was diagnosed with juvenile idiopathic polyarticular arthritis (JIA) complicated by IgA deficiency in the 22q11 deletion syndrome. There is an increased prevalence of chronic arthritis in association with 22q11 deletion syndrome with IgA deficiency, but the reasons for this association are unknown. This study evaluated the possible correlation between cytokines and the susceptibility to chronic arthritis in the 22q11 deletion syndrome with IgA deficiency. The expression of pro-inflammatory cytokines such as IL-8, IL-6, MIP-1??, and MCP-1 suggests that T and B cells, macrophages and neutrophils modulate joint inflammation by an immune response. And the presence of IL-10 and IL-5 might suggest that the synovitis is associated with JIA and IgA deficiency.     

Radiographic progression in children with polyarticular juvenile rheumatoid arthritis: a pilot study

OBJECTIVE: To assess disease progression on hand/wrist x rays from children with polyarticular juvenile rheumatoid arthritis. METHODS: Initial and subsequent films of 13 white children (10 girls) were read blind by a paediatric radiologist for the presence of joint space narrowing (JSN), erosions, and relative carpal length (RCL). RESULTS: One child had subcutaneous nodules; one (of 11) was rheumatoid factor positive; six were ANA positive. Median age at diagnosis was 10.7 years (2.5 to 15.9). Median number of involved joints (swelling, pain, or decreased range of motion) at diagnosis was 16 (6 to 33). Four initial x rays had either erosions or JSN. Subsequent x rays were done at (median) 13.3 (8.3 to 24.9) months after initial x rays. One of 10 subsequent x rays had shortened RCL, and six of 13 were worse than the initial ones. Four of these developed new erosions, one had increased number of erosions, and one developed new JSN. CONCLUSIONS: About half the children with polyarticular juvenile rheumatoid arthritis will have evidence of radiographic progression within two years after diagnosis. Thus newly diagnosed children are at high risk of substantial joint destruction and potential disability, emphasising the need for prompt treatment.     

SLC11A1 (formerly NRAMP1) gene polymorphisms and tuberculosis susceptibility: a meta-analysis.

OBJECTIVE: Although many case-control studies have investigated the association between the SLC11 A1 gene polymorphisms and tuberculosis (TB) susceptibility, results were conflicting due to limited power. We reviewed the literature systematically by means of meta-analysis, provided a quantitative summary estimate on the association with TB, and examined some sources of between-study heterogeneity. DESIGN: We searched databases (MEDLINE, PUBMED and OVID) from January 1995 to December 2004 using 'gene' or 'SLC11A1' or 'NRAMP1', in combination with 'tuberculosis', performed a manual search of citations from relevant original studies and review articles, or corresponded with authors. RESULTS: The summary ORs for studies with 3'UTR, D543N, INT4 and 5'(GT)n loci allele variants in the SLC11A1 gene were 1.33 (95%CI 1.08-1.63), 1.67 (95%CI 1.36-2.05), 1.14 (95%CI 0.96-1.35) and 1.32 (95%CI 1.03-1.68), respectively, compared with their corresponding common alleles. The pooled ORs by sub-group analyses for the four loci described above were 1.20 (95%CI 0.86-1.68), 1.69 (95%CI 1.14-2.50), 1.50 (95%CI 1.17-1.91), and 1.31 (95%CI 1.05-1.64) in subjects of African descent, 1.46 (95%CI 1.10-1.94), 1.65 (95%CI 1.29-2.12), 0.91 (95%CI 0.66-1.25) and 1.86 (95%CI 1.33-2.62) in Asian subjects, 1.81 (95%CI 0.66-4.93), 1.79 (95%CI 0.72-4.47), 0.87 (95%CI 0.61-1.22) and 1.02 (95%CI 0.35-2.99) in European subjects. CONCLUSIONS: Polymorphisms at the four loci had no statistically significant association between the SLC11A1 variants and susceptibility to TB in subjects of European descent, while they showed a statistically significant association in Asian subjects (except the INT4 variant), African subjects (except the 3'UTR variant) and the population as a whole (except the INT4 variant).     

Switching the therapy from etanercept to infliximab in a child with rheumatoid factor positive polyarticular juvenile idiopathic arthritis

Tumor necrosis factor α (TNFα)-blocking agents have been used increasingly in the treatment of severe refractory juvenile idiopathic arthritis (JIA). However, some patients have been forced to discontinue these agents because of the lack of efficacy or adverse events. In these situations, cases of switching from one TNF-blocking agent to another are reported in rheumatoid arthritis, but there are few cases in JIA. This report documents the case of a patient with JIA who improved following a switch from etanercept to infliximab.     

Switching the therapy from etanercept to infliximab in a child with rheumatoid factor positive polyarticular juvenile idiopathic arthritis

Abstract

Tumor necrosis factor α (TNFα)-blocking agents have been used increasingly in the treatment of severe refractory juvenile idiopathic arthritis (JIA). However, some patients have been forced to discontinue these agents because of the lack of efficacy or adverse events. In these situations, cases of switching from one TNF-blocking agent to another are reported in rheumatoid arthritis, but there are few cases in JIA. This report documents the case of a patient with JIA who improved following a switch from etanercept to infliximab.     

Therapeutic experience with infliximab in a patient with polyarticular juvenile idiopathic arthritis and uveitis

A pediatric patient with prolonged seronegative polyarticular juvenile idiopathic arthritis (JIA) and concomitant aggressive, anterior uveitis refractory to any conventional antirheumatic therapy was treated with infliximab. Arthritis and C-reactive protein (CRP) values showed prompt positive effects but, after 6 weeks, returned gradually to initial values despite ongoing therapy. In contrast, a more sustained therapeutic effect was observed on the uveitis, with increased visual acuity and reduced inflammatory signs of the affected eye. However, this benefit was also lost at week 30, after which infliximab had to be discontinued due to side effects. To conclude, in polyarticular seronegative JIA, infliximab showed a transient beneficial effect which was more pronounced on uveitis than arthritis.     

Polymorphism at NRAMP1 and D2S1471 loci associated with juvenile rheumatoid arthritis

OBJECTIVE: To examine the role of NRAMP1 in susceptibility to juvenile rheumatoid arthritis (JRA). METHODS: DNA from 119 JRA patients (72 pauciarticular, 47 polyarticular) and 111 healthy controls from Latvia was genotyped for a functional repeat polymorphism in the promoter of NRAMP1 and a linked (<150 kb) microsatellite D2S1471. The findings were compared with those from HLA-DQ alleles typed previously. Chi-square analyses were performed using the Mantel-Haenszel test and stratification according to pure Latvian or pure Russian descent. Haplotype analysis was performed using the Associate program to implement the expectation-maximization algorithm based on the gene-counting technique. RESULTS: Allele 3 at NRAMP1 conferred increased risk (odds ratios [ORs] 2.26, 2.31, and 2.19; P = 0.0006, 0.003, and 0.019) of disease in the JRA, pauciarticular, and polyarticular patient groups, respectively. Allele 2 conferred protection (OR 0.44, 0.43, and 0.46). Alleles at D2S1471 that conferred susceptibility (6 and 12) or protection (11) did so only when on a haplotype with alleles 3 or 2, respectively, at NRAMP1. Allele 3 at NRAMP1 was additive with HLA-DQ7 for susceptibility (OR 3.71, 3.71, and 4.02), and allele 2 at NRAMP1 was additive with HLA-DQ5 for protection (OR 0.19, 0.08, and 0.12). CONCLUSION: The NRAMP1 allele conferring susceptibility to JRA drives high levels of NRAMP1 expression, while the allele associated with protection drives low levels. These 2 alleles are inversely associated with susceptibility to infectious disease, consistent with their maintenance in populations through balancing selection.     

Association analysis of juvenile idiopathic arthritis genetic susceptibility factors in Estonian patients

Clinical Rheumatology - Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic condition of childhood. Genetic association studies have revealed several JIA susceptibility loci...