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Background Infections are an important cause of morbidity and mortality in patients with rheumatoid arthritis. Patients receiving immunosuppressive or anti-tumor necrosis factor (TNF) agents are vulnerable to fungal infections, including those derived from Aspergillus species. Detection of the Aspergillus galactomannan antigen in serum is useful for the early diagnosis of invasive aspergillosis in patients with hematological malignancies. However, its usefulness for detecting early invasive aspergillosis in rheumatoid arthritis patients remains unestablished. Methods Galactomannan antigen levels were measured in 340 patients (311 female patients). For patients who exhibited galactomannan antigen levels ≥0.5 during the initial examination, a second examination was performed 3–6 months later. Conventional blood tests and chest radiography were also performed. Results Elevated galactomannan antigen levels (≥0.5) were observed in 62 (18.2%) of 340 patients during the initial examination. A second examination was performed in 56 of 62 patients, 50 of whom exhibited elevated antigen levels. Elevated antigen levels were not associated with the use of any drug including anti-TNF agents. Serum galactomannan antigen levels were correlated with the albumin/globulin ratio ( r =−0.19, p r =0.17, p =0.001), and hemoglobin concentration ( r =−0.15, p =0.005). No patient was clinically diagnosed with invasive aspergillosis during the study period. Conclusions Serum galactomannan antigen levels are frequently elevated in a nonspecific manner in patients with rheumatoid arthritis.

We investigated the expression of membrane-type matrix metalloproteinase (MT-MMP) and matrix metalloproteinase (MMP) mRNAs in synovial tissue from patients with rheumatoid arthritis (RA, n = 5) or osteoarthritis (OA, n = 5) by Northern blot analysis. Northern analysis demonstrated strong expression of MT1-MMP, MT3-MMP, MMP-1, and MMP-3 and weak expression of MT2-MMP and MMP-8 in synovial tissue from patients with RA or OA. MT4-MMP was not detected. No significant difference was shown in the expression of MT-MMP mRNAs between RA and OA. Synovial tissue of RA or OA patients expressed MT-MMPs as well as MMPs. These results indicate that, in addition to MMPs, MT1-MMP, MT3-MMP, and probably MT2-MMP may play a role in the degradation of bone and cartilage matrix in RA and OA. Such information may provide a clue to the development of a novel therapeutic approach targeted on the prevention of joint destruction.

CTLA-4 is considered to be one of the attractive candidates for the susceptibility genes to rheumatic diseases. In the present study, the association of CTLA-4 polymorphism with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) was examined in the Japanese population using the case-control association analysis. Polymerase chain reaction-preferential homoduplex formation assay (PCR-PHFA) was applied for the screening of genetic variations and for the genotyping of a large number of samples. A greater proportion of Japanese patients with RA (44%) and SLE (44%) compared with healthy individuals (37%) had exon 1 49 G/G genotype, but the difference did not reach statistical significance. However, when the patients with RA and healthy individuals were stratified according to HLA-DRB1 alleles, a weakly significant increase of the positivity of CTLA-4 49G allele was observed in HLA-DRB1*0405-positive patients (87%) compared with DRB1*0405-positive healthy individuals (71%) (P = 0.014, odds ratio = 2.77). These results indicate that CTLA-4 exon 1 polymorphism does not contribute greatly to the susceptibility to RA and SLE, at least in Japanese, although the presence of CTLA4 49G allele could be a minor predisposing factor for RA in HLA-DRB1*0405-positive individuals. In addition, PCR-PHFA was shown to be useful for a mass screening of gene variations.

We previously reported that rheumatoid factors (RFs) might bear the internal image of Fc gamma-binding proteins (FcBPs) of herpes family viruses, suggesting the possibility that some RFs may be produced as antiidiotypic antibodies to anti-viral FcBP antibodies. Since human cytomegalovirus (HCMV) has been implicated in the pathogenesis of RA, we made an attempt to detect antibodies to 65 KD major HCMV FcBP in sera and synovial fluid from patients with RA. Western blotting was performed using HCMV-infected MRC-5 cell lysate as the antigen. Eleven of 23 patients with RA possessed strong serum antibodies to HCMV-65 KD protein, whereas such antibodies were found in only 2 of 23 normal controls. In the synovial fluid, 10 of 19 RA patients showed anti-HCMV 65 KD reactivity. Pepsin-digested IgG retained anti-65 KD reactivity, indicating that false-positive reaction due to the presence of IgG Fc portion and/or RF was unlikely. 65 KD protein was shown to be different from human heat shock proteins (hsps) using monoclonal antibodies against human hsps. Patients' IgG F(ab')2 also reacted with the 65 KD protein of purified HCMV virion itself. These results support the possibility that some RFs could be produced as antiidiotypic antibodies to anti-viral FcBP antibodies.

Leukocyte immunoglobulin-like receptors (LILRs) are inhibitory, stimulatory or soluble receptors encoded within the leukocyte receptor complex. Some LILRs are extensively polymorphic, and exhibit evidence for balancing selection and association with disease susceptibility. LILRA2 (LIR7/ILT1) is an activating receptor highly expressed in inflammatory tissues, and is involved in granulocyte and macrophage activation. In this study, we examined the association of LILRA2 and adjacently located LILRA1 with systemic lupus erythematosus (SLE), rheumatoid arthritis (RA) and microscopic polyangiitis (MPA). Polymorphism screening detected a LILRA2 SNP (rs2241524 GA) that disrupts splice acceptor site of intron 6. Case-control association studies on 273 Japanese SLE, 296 RA, 50 MPA and 284 healthy individuals revealed increase of genotype A/A in SLE (12.1%, odds ratio (OR) 1.82, 95% confidence interval (CI) 1.02-3.24, P=0.041) and in MPA (16.0%, OR 2.52, 95% CI 1.07-5.96, P=0.049) compared with healthy individuals (7.0%). The risk allele caused an activation of a cryptic splice acceptor site that would lead to a novel LILRA2 isoform lacking three amino acids in the linker region (Delta 419-421). Flow cytometry indicated that this isoform was expressed on the surface of monocytes. These findings suggested that LILRA2 Delta 419-421 isoform encoded by the splice site SNP may play a role in SLE and MPA.

Restriction fragment length polymorphism (RFLP) of the two genes for complement C4A and C4B was studied in 56 Japanese patients with rheumatoid arthritis (RA) and 161 normal individuals. Hindlll digestion revealed six common patterns, from which the segregation of three common RFLP-types were deduced; 32-15 kb, 32-25-15 kb, and 32-20-13-6.5 kb. The last type showed positive associations with C4B5 and HLA-DR4. In the RA patients, an increase of this type was found as well as a decrease of the 32-15 kb/32-25-15 kb heterozygotes.

Objectives. A polymorphism of APRIL, c.199G > A (Gly67Arg), has been reported to be associated with systemic lupus erythematosus (SLE) in Japanese. To identify the causative polymorphism, we screened for polymorphisms of APRIL as well as TWEAK (TNFSF12), a closely located gene that generates a fusion protein TWE-PRIL by intergenic splicing. Association of APRIL and TWEAK with rheumatoid arthritis (RA) was examined in parallel. Methods. Polymorphisms were screened by direct sequencing. Association was analysed by case-control analysis using 266 SLE, 298 RA and 208 healthy individuals. Allele-specific difference in the mRNA level was examined using RNA difference plot analysis. Serum APRIL level was measured by ELISA. Results. The protective effect of APRIL c.199A/A homozygotes in SLE was replicated (odds ratio 0.50, 95% confidence interval 0.30–0.83, P ¼ 0.0073; pooled P ¼ 0.0001, Pcorr ¼ 0.007). In addition, association of c.287A > G (Asn96Ser, P ¼ 0.0064, allele frequency) and c.*263C > T (3’ untranslated region, P ¼ 0.025, allele frequency) was detected. c.199G-c.287A (67Gly-96Asn) haplotype was found to confer risk for SLE, while c.199A-c.287G (67Arg-96Ser) was protective. Association of TWEAK was observed neither for SLE nor RA. APRIL mRNA was increased in SLE-associated c.*263T allele. In addition, serum APRIL was undetectable in all six healthy controls homozygous for the protective c.199A-c.287G haplotype (P ¼ 0.015). Conclusions. In addition to replicating the protective role of APRIL c.199A/A, two additional SNPs in APRIL were found to be associated with SLE. Presence of a protective haplotype and a risk haplotype was demonstrated. The mechanism of association was suggested to be altered expression at the protein and mRNA levels.

Polymorphisms in the genomic region encoding B lymphoid tyrosine kinase ( BLK ) and family with sequence similarity 167, member A ( FAM167A , also referred to as C8orf13 ) at 8p23.1 have been associated with systemic lupus erythematosus (SLE) in Caucasian1 2 and Asian3 4 populations. A recent genome-wide study in a north American population showed new associations with rheumatoid arthritis (RA), among which was a single nucleotide polymorphism (SNP) rs2736340 in the intergenic region of BLK and FAM167A .5 In the HapMap Japanese samples (http://www.hapmap.org/index.html.ja), this SNP is in absolute linkage disequilibrium ( r 2=1) with rs13277113, previously associated with SLE.1,–,4 We have shown that the population frequency of the risk genotype rs13277113A/A and the OR for SLE …

Combined therapy with lobenzarit disodium (CCA), a disease-modifying antirheumatic drug (DMARD), and Boi-ogi-to has been reported to produce synergistic effects. We investigated whether these effects could be produced even in patients suffering from intractable rheumatoid arthritis (RA). The subjects of this study were two separate groups of female patients with high intractable RA activity (erythrocyte sedimentation rate (ESR) >50) for whom therapy with Boi-ogi-to was considered to be indicated. In the first group (group A), CCA was given after Boi-ogi-to had been administered. In the second group (group B), both CCA and Boi-ogi-to had been administered. In the second goup (group B), both CCA and Boi-ogi-to were administered simultaneously. The daily dose of CCA was 80 mg, which was less than the dose generally given. A favorable response was seen in 66% of the patients in group A and in 46% of those in group B; the total percentage for both groups was 55%. The efficacy rates obtained by this study were therefore higher than those reported in a previous study in which only CCA had been administered. In our findings, moreover, the ESR improved to almost the same degree as in a study reported previously. These results indicate that combined therapy of CCA with Boi-ogi-to produces a synergistic effect even in patients suffering from intractable RA.

Introduction TNFAIP3 interacting protein 1, TNIP1 (ABIN-1) is involved in inhibition of nuclear factor-κB (NF-κB) activation by interacting with TNF alpha-induced protein 3, A20 (TNFAIP3), an established susceptibility gene to systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Recent genome-wide association studies revealed association of TNIP1 with SLE in the Caucasian and Chinese populations. In this study, we investigated whether the association of TNIP1 with SLE was replicated in a Japanese population. In addition, association of TNIP1 with RA was also examined. Methods A case-control association study was conducted on the TNIP1 single nucleotide polymorphism (SNP) rs7708392 in 364 Japanese SLE patients, 553 RA patients and 513 healthy controls. Results Association of TNIP1 rs7708392C was replicated in Japanese SLE (allele frequency in SLE: 76.5%, control: 69.9%, P = 0.0022, odds ratio [OR] 1.40, 95% confidence interval [CI] 1.13-1.74). Notably, the risk allele frequency in the healthy controls was considerably greater in Japanese (69.9%) than in Caucasians (24.3%). A tendency of stronger association was observed in the SLE patients with renal disorder (P = 0.00065, OR 1.60 [95%CI 1.22-2.10]) than in all SLE patients (P = 0.0022, OR 1.40 [95%CI 1.13-1.74]). Significant association with RA was not observed, regardless of the carriage of human leukocyte antigen DR β1 (HLA-DRB1) shared epitope. Significant gene-gene interaction between TNIP1 and TNFAIP3 was detected neither in SLE nor RA. Conclusions Association of TNIP1 with SLE was confirmed in a Japanese population. TNIP1 is a shared SLE susceptibility gene in the Caucasian and Asian populations, but the genetic contribution appeared to be greater in the Japanese and Chinese populations because of the higher risk allele frequency. Taken together with the association of TNFAIP3, these observations underscore the crucial role of NF-κB regulation in the pathogenesis of SLE.

The sugar chains of IgG samples purified from sera of patients with rheumatoid arthritis (RA) contain many fewer galactose residues than those from sera of healthy individuals. Enzymatic studies revealed that the low galactose content in the IgGs of RA patients results from the reduced activity in the B cells of a galactosyltransferase (EC 2.4.1.90), which preferentially transfers galactose to asialo-agalacto-IgG. Asialo-agalacto-transferrin and asialo-ovine submaxillary mucin were also galactosylated by detergent-activated human B cell homogenates. However, no difference in the enzymatic activities toward these two acceptors was detected between the B cells from RA patients and from non-RA patients and healthy individuals. Enzyme kinetic studies revealed that an affinity of the galactosyltransferase in the B cells from RA patients was lowered for UDP-Gal but not for asialo-agalacto-IgG, while the affinities for UDP-Gal and asialo-agalacto-transferrin of the galactosyltransferase were not changed between the B cells from RA patients and from non-RA patients and healthy individuals in accordance with their enzyme activities. The results indicated that the reduced galactosyltransferase activity toward asialo-agalacto-IgG in the B cells from RA patients can be ascribed to the lowered affinity for UDP-Gal.

Objective New polymorphisms affecting transcriptional activity were recently reported within the 5′-flanking region of the tumor necrosis factor α gene (TNFA). In addition, genome-wide linkage screening indicated 1p36 as one of the candidate chromosomal regions where the TNF receptor II gene (TNFR2) is located. In the present study, HLA–DRB1, TNFA promoter, and TNFR2 genotypes were determined to examine whether these polymorphisms are associated with rheumatoid arthritis (RA), either independently or in combination. Methods Genotypes of HLA–DRB1, TNFA upstream promoter, and TNFR2 codon 196 were determined in 545 Japanese patients with RA and 265 healthy controls. Association of these genes with susceptibility to RA was analyzed both independently and after stratification by one of the genotypes. Results As expected, the HLA–DRB1 shared epitope was strongly associated with RA. In addition, a significant negative association of DRB1*1405 and 1302 was observed. Furthermore, DRB1*1405 was suggested to possess a protective role for the development of RA in DRB1*0405-positive individuals. A significant increase in TNFA-U02 in RA was detected, which was not independent of DRB1*0405. A significant association was not observed between TNFR2-196M/R polymorphism and RA. Conclusion Among the 3 genes examined in this study, HLA–DRB1 was considered to be most strongly associated with RA.

We investigated polymorphisms of complement components C2, C4, and factor B (BF) in Japanese patients with rheumatoid arthritis (RA). The frequencies of C4AQ0 (32.1%) and C4B5 (35.9%) among RA patients were significantly higher than among healthy control subjects. C4B5 was strongly associated with HLA-Bw54, Bw59, DR4.1, and DQw4. C4AQ0 showed no association with HLA-Bw54 or Bw59, but there was weak association with HLA-DR4.1 and DQw4. The number of persons with both C4AQ0 and C4B5 was significantly higher in the RA patient group (relative risk 13.5). C2C and BFS were the most common alleles in RA patients, as well as in healthy control subjects. These data support the existence of 2 different putative susceptibility haplotypes (HLA-Bw54 or Bw59;C2C; BFS;C4A3;C4B5;DR4.1;DQw4 and C2C;BFS; C4AQ0;C4B1 or C4B2) in Japanese patients with RA.

The levels of kallikrein and collagenase in synovial fluid from rheumatoid arthritis (RA) patients were examined and the role of kallikrein in procollagenase activation is discussed. Both prekallikrein and active kallikrein in synovial fluid from patients with RA were significantly elevated when compared to synovial fluid from patients with osteoarthritis (OA). In RA synovial fluid, the ratio of the active form to total kallikrein was also higher than that in OA synovial fluid. Both active collagenase and the alpha 2-macroglobulin (alpha 2M)-collagenase complex in RA synovial fluid were higher than in OA synovial fluid. A partial correlation (r = 0.58) between active kallikrein and total collagenase (active and alpha 2M-collagenase complex) was observed in RA synovial fluid. These observations indicate that both kallikrein and collagenase are associated with the destruction of cartilage, but the role of kallikrein in procollagenase activation was not fully clarified.

SUMMARY A highly significant association of an amino acid sequence, ‘70Q71R72R73A74A’ located on the DRβ-1 chain, with rheumatoid arthritis (RA) was confirmed in Japanese patients using polymerase chain reaction. The ‘70QRRA74A’ is the most plausible candidate of susceptibility epitope in Japanese RA patients. The patients carrying the sequence showed slightly higher but not significant familial incidence. The positivity of the ‘QRRAA’ showed no effect on the positivity of the rheumatoid factor, rheumatoid nodules, and extra-articular signs. Also no significant differences in other clinical parameters (ESR, CRP, Hb, A/G) and age at onset were observed regarding the positivity. The risk that the ‘QRRAA’ positive subjects would suffer from RA was estimated to be about 1.3% which meant 7.2 times easier to get RA than those without ‘QRRAA’.