Tomoki Origuchi

Proposal for a new clinical entity, IgG4-positive multiorgan lymphoproliferative syndrome: analysis of 64 cases of IgG4-related disorders

Background: Mikulicz’s disease (MD) has been considered as one manifestation of Sjögren’s syndrome (SS). Recently, it has also been considered as an IgG4-related disorder. Objective: To determine the differences between IgG4-related disorders including MD and SS. Methods: A study was undertaken to investigate patients with MD and IgG4-related disorders registered in Japan and to set up provisional criteria for the new clinical entity IgG4-positive multiorgan lymphoproliferative syndrome (IgG4+MOLPS). The preliminary diagnostic criteria include raised serum levels of IgG4 (>135 mg/dl) and infiltration of IgG4+ plasma cells in the tissue (IgG4+/IgG+ plasma cells >50%) with fibrosis or sclerosis. The clinical features, laboratory data and pathologies of 64 patients with IgG4+MOLPS and 31 patients with typical SS were compared. Results: The incidence of xerostomia, xerophthalmia and arthralgia, rheumatoid factor and antinuclear, antiSS-A/Ro and antiSS-B/La antibodies was significantly lower in patients with IgG4+MOLPS than in those with typical SS. Allergic rhinitis and autoimmune pancreatitis were significantly more frequent and total IgG, IgG2, IgG4 and IgE levels were significantly increased in IgG4+MOLPS. Histological specimens from patients with IgG4+MOLPS revealed marked IgG4+ plasma cell infiltration. Many patients with IgG4+MOLPS had lymphocytic follicle formation, but lymphoepithelial lesions were rare. Few IgG4+ cells were seen in the tissue of patients with typical SS. Thirty-eight patients with IgG4+MOLPS treated with glucocorticoids showed marked clinical improvement. Conclusion: Despite similarities in the involved organs, there are considerable clinical and pathological differences between IgG4+MOLPS and SS. Based on the clinical features and good response to glucocorticoids, we propose a new clinical entity: IgG4+MOLPS.

A prediction rule for disease outcome in patients with undifferentiated arthritis using magnetic resonance imaging of the wrists and finger joints and serologic autoantibodies

OBJECTIVE To evaluate whether magnetic resonance imaging (MRI) of the wrists and finger joints and an analysis of serologic autoantibodies are clinically meaningful for the subsequent development of rheumatoid arthritis (RA) in patients with undifferentiated arthritis (UA). METHODS A total of 129 patients with UA, a disease status formally confirmed by a rheumatologist over a period of at least 1 year, were included. Gadolinium-diethylenetriamine-enhanced MRI of both wrists and finger joints and serologic variables were examined upon admission to our Early Arthritis Clinic at Nagasaki University. After a prospective followup of 1 year, a predictive value for the development of RA was determined for each patient. RESULTS The subjects were evaluated for their positive or negative status with respect to 3 objective measures at study entry: anti-cyclic citrullinated peptide (anti-CCP) antibodies and/or IgM-rheumatoid factor, MRI-proven symmetric synovitis, and MRI-proven bone edema and/or bone erosion. The patients who were positive for at least 2 of these measures progressed to RA at 1 year with a 79.7% positive predictive value (PPV), 63.0% negative predictive value, 75.9% specificity, 68.0% sensitivity, and 71.3% accuracy. Furthermore, in 22 UA patients positive for both anti-CCP antibodies and MRI-proven bone edema who were considered to have progressed to RA at 1 year, the PPV was increased to 100%. A close correlation was found between the present rule and that established in the Leiden Early Arthritis Cohort. CONCLUSION MRI-proven early joint damage in conjunction with serologic autoantibodies is efficient in predicting progression from UA to RA. This method can be used to identify patients who would benefit from early treatment with disease-modifying antirheumatic drugs.

The diagnostic utility of anti-melanoma differentiation-associated gene 5 antibody testing for predicting the prognosis of Japanese patients with DM

OBJECTIVE Interstitial lung disease (ILD), especially rapidly progressive ILD (RPILD), is a major poor prognostic factor in patients with DM. We investigated the association of anti-melanoma differentiation-associated gene 5 (MDA5) antibody (Ab) with clinical characteristics and mortality in Japanese patients with DM. METHODS Seventy-nine DM patients, comprising 58 classic DM and 21 clinically amyopathic DM (CADM) patients, were enrolled. Serum Abs were screened by immunoprecipitation assays, and an immunosorbent assay (ELISA) was used for MDA5. The relationships of clinical characteristics and mortality with each Ab were investigated. RESULTS Anti-MDA5 Ab was detected in 17 patients. Anti-clinically amyopathic DM 140  kDa polypeptide Abs (anti-CADM-140 Abs) were found in 16 of the 17 anti-MDA5 Ab(+) patients. Skin ulcers, palmar papules, CADM, RPILD and mediastinal emphysema were widely distributed in anti-MDA5 Ab(+) patients. Mortality at 6 months as well as 5 years was also significantly higher in anti-MDA5 Ab(+) patients than in anti-MDA5 Ab(-) patients. In a multivariable Cox regression analysis, mortality was independently associated with anti-MDA5 Ab (relative hazard 6.33; 95% CI 1.43, 28.0). All of the deaths in anti-MDA5 Ab(+) patients were attributed to respiratory failure of RPILD; however, RPILD did not worsen in any of the anti-MDA5 Ab(+) patients who survived the first 6 months. CONCLUSION The presence of anti-MDA5 Ab identifies the characteristic skin, musculoskeletal, pulmonary and prognostic features in patients with DM. In addition, anti-MDA5 Ab seems to predict a group of patients with CADM-complicated fatal RPILD.

Cutoff Values of Serum IgG4 and Histopathological IgG4+ Plasma Cells for Diagnosis of Patients with IgG4-Related Disease.

IgG4-related disease is a new disease classification established in Japan in the 21st century. Patients with IgG4-related disease display hyper-IgG4-gammaglobulinemia, massive infiltration of IgG4+ plasma cells into tissue, and good response to glucocorticoids. Since IgG4 overexpression is also observed in other disorders, it is necessary to diagnose IgG4-related disease carefully and correctly. We therefore sought to determine cutoff values for serum IgG4 and IgG4/IgG and for IgG4+/IgG+ plasma cells in tissue diagnostic of IgG4-related disease. Patients and Methods. We retrospectively analyzed serum IgG4 concentrations and IgG4/IgG ratio and IgG4+/IgG+ plasma cell ratio in tissues of 132 patients with IgG4-related disease and 48 patients with other disorders. Result. Serum IgG4 >135  mg/dl demonstrated a sensitivity of 97.0% and a specificity of 79.6% in diagnosing IgG4-related disease, and serum IgG4/IgG ratios >8% had a sensitivity and specificity of 95.5% and 87.5%, respectively. IgG4+cell/IgG+ cell ratio in tissues >40% had a sensitivity and specificity of 94.4% and 85.7%, respectively. However, the number of IgG4+ cells was reduced in severely fibrotic parts of tissues. Conclusion. Although a recent unanimous consensus of all relevant researchers in Japan recently established the diagnostic criteria for IgG4-related disease, findings such as ours indicate that further discussion is needed.

RS3PE syndrome presenting as vascular endothelial growth factor associated disorder

Objectives: To characterise serum concentrations of various cytokines and detection by magnetic resonance imaging (MRI) of synovial hypervascularity in patients with remitting seronegative symmetrical synovitis with pitting oedema (RS3PE) syndrome before and after corticosteroid treatment. Methods: Vascular endothelial growth factor165 (VEGF165), tumour necrosis factor α (TNFα), and interleukin 1β (IL1β) were measured by enzyme linked immunosorbent assay (ELISA) in serum samples from three patients with RS3PE syndrome. As controls, serum samples from 26 healthy volunteers, 12 patients with rheumatoid arthritis, 10 patients with systemic lupus erythematosus, 13 patients with polymyositis/dermatomyositis, 13 patients with vasculitis syndrome, and 6 patients with mixed connective tissue disease were also analysed. Synovial hypervascularity of patients with RS3PE syndrome was estimated by rate of enhancement (E-rate) in a dynamic MRI study. Results: Serum concentrations of VEGF165 (mean (SD) 2223.3 (156.3) pg/ml) were significantly higher in patients with active RS3PE syndrome than in controls before corticosteroid treatment. TNFα and IL1β levels were similar in patients and controls. Synovial hypervascularity in affected joints and subcutaneous oedema decreased during corticosteroid treatment, in parallel with the fall in serum VEGF165. Conclusions: VEGF promotes synovial inflammation and vascular permeability in patients with RS3PE syndrome, suggesting that RS3PE can be classified as a VEGF associated disorder.

Granzyme B leakage-induced cell death: a new type of activation-induced natural killer cell death

Activation‐induced natural killer (NK) cell death is very rapid compared to activation‐induced T or B cell death. Here we show that NK cell activation is accompanied by the leakage of granzymeB from intracellular granules into the cytoplasm. Evidence for granzyme B leakage includes the formation of granzyme B/serine proteinase inhibitor 9 (PI‐9) complexes that are detected by immunoprecipitation as well as colocalization of granzyme B and PI‐9 detected by immunocytochemistry. The pro‐apoptotic molecule Bid, a specific substrate for granzyme B, was cleaved within 2 min following CD2‐induced NK cell activation, suggesting that granzyme B triggers apoptosis by directing Bid to mitochondrial membranes. The granzyme B/PI‐9 protein ratio was found to mirror the percentage of CD2‐induced NK cell death, suggesting that an excess of leaked granzyme B over its inhibitor is a major determinant of cell death. We suggest that granzyme B leakage‐induced cell death is an important determinant of activation‐induced NK cell death and that this process may be important for the fate of NK cells which encounter malignant or virus‐infected cells.

Low‐level laser irradiation promotes the recovery of atrophied gastrocnemius skeletal muscle in rats

Low‐level laser (LLL) irradiation promotes proliferation of muscle satellite cells, angiogenesis and expression of growth factors. Satellite cells, angiogenesis and growth factors play important roles in the regeneration of muscle. The objective of this study was to examine the effect of LLL irradiation on rat gastrocnemius muscle recovering from disuse muscle atrophy. Eight‐week‐old rats were subjected to hindlimb suspension for 2 weeks, after which they were released and recovered. During the recovery period, rats underwent daily LLL irradiation (Ga–Al–As laser; 830 nm; 60 mW; total, 180 s) to the right gastrocnemius muscle through the skin. The untreated left gastrocnemius muscle served as the control. In conjunction with LLL irradiation, 5‐bromo‐2′‐deoxyuridine (BrdU) was injected subcutaneously to label the nuclei of proliferating cells. After 2 weeks, myofibre diameters of irradiated muscle increased in comparison with those of untreated muscle, but did not recover back to normal levels. Additionally, in the superficial region of the irradiated muscle, the number of capillaries and fibroblast growth factor levels exhibited significant elevation relative to those of untreated muscle. In the deep region of irradiated muscle, BrdU‐positive nuclei of satellite cells and/or myofibres increased significantly relative to those of the untreated muscle. The results of this study suggest that LLL irradiation can promote recovery from disuse muscle atrophy in association with proliferation of satellite cells and angiogenesis.

Osteoprotegerin (OPG) acts as an endogenous decoy receptor in tumour necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis of fibroblast-like synovial cells

We examined the role of osteoprotegerin (OPG) on tumour necrosis factor‐related apoptosis‐inducing ligand (TRAIL)‐induced apoptosis in rheumatoid fibroblast‐like synovial cells (FLS). OPG protein concentrations in synovial fluid from patients with rheumatoid arthritis (RA) correlated with those of interleukin (IL)‐1β or IL‐6. A similar correlation was present between IL‐1β and IL‐6 concentrations. Rheumatoid FLS in vitro expressed both death domain‐containing receptors [death receptor 4 (DR4) and DR5] and decoy receptors [decoy receptor 1 (DcR1) and DcR2]. DR4 expression on FLS was weak compared with the expression of DR5, DcR1 and DcR2. Recombinant TRAIL (rTRAIL) rapidly induced apoptosis of FLS. DR5 as well as DR4 were functional with regard to TRAIL‐mediated apoptosis induction in FLS; however, DR5 appeared be more efficient than DR4. In addition to soluble DR5 (sDR5) and sDR4, OPG administration significantly inhibited TRAIL‐induced apoptogenic activity. OPG was identified in the culture supernatants of FLS, and its concentration increased significantly by the addition of IL‐1β in a time‐dependent manner. Neither IL‐6 nor tumour necrosis factor (TNF)‐α increased the production of OPG from FLS. TRAIL‐induced apoptogenic activity towards FLS was reduced when rTRAIL was added without exchanging the culture media, and this was particularly noticeable in the IL‐1β‐stimulated FLS culture; however, the sensitivity of FLS to TRAIL‐induced apoptosis itself was not changed by IL‐1β. Interestingly, neutralization of endogenous OPG by adding anti‐OPG monoclonal antibody (MoAb) to FLS culture restored TRAIL‐mediated apoptosis. Our data demonstrate that OPG is an endogenous decoy receptor for TRAIL‐induced apoptosis of FLS. In addition, IL‐1β seems to promote the growth of rheumatoid synovial tissues through stimulation of OPG production, which interferes with TRAIL death signals in a competitive manner.

The power Doppler ultrasonography score from 24 synovial sites or 6 simplified synovial sites, including the metacarpophalangeal joints, reflects the clinical disease activity and level of serum biomarkers in patients with rheumatoid arthritis

OBJECTIVE We evaluated the significance of the power Doppler ultrasonography (PDUS) score by comparing it with serum biomarkers and clinical disease activity. METHODS We measured the PDUS scores of 24 synovial sites in 12 joints in 22 RA patients. For convenience, the PDUS scores of six synovial sites in six joints were also examined. Each joint was scored for a power Doppler (PD) signal on a scale from 0 to 3. The PDUS scores are the sums of the PD signal scores for the 24 synovial sites or the 6 synovial sites. On the same day, serum variables as well as clinical disease activity were evaluated. RESULTS The PDUS scores from the 24 joint sites were significantly positively correlated with DAS of 28 joints (DAS-28), simplified disease activity index (SDAI), clinical disease activity index (CDAI) and serum biomarkers including MMP-3, VEGF and tissue inhibitor of metalloproteinases-1 (TIMP-1). Accordingly, the PDUS scores from the six synovial sites greatly correlated with those from the 24 joint sites. Clinical disease activities as well as serum variables were also clearly correlated with the PDUS scores from the six synovial sites. CONCLUSION The standard as well as the simplified PDUS scores well reflected clinical disease activity and serum variables, including angiogenic factors. Our data reaffirm the utility of ultrasonography for monitoring disease activity in patients with RA.

Association of distinct clinical subsets with myositis-specific autoantibodies towards anti-155/140-kDa polypeptides, anti-140-kDa polypeptides, and anti-aminoacyl tRNA synthetases in Japanese patients with dermatomyositis: a single-centre, cross-sectional study.

Objective: To determine the association of distinct clinical subsets with myositis‐specific autoantibodies (MSAs) towards anti‐155/140‐kDa polypeptides [anti‐155/140 antibodies (Abs)], anti‐140‐kDa polypeptides (anti‐140 Abs), and anti‐aminoacyl tRNA synthetases (ARS Abs) in Japanese patients with dermatomyositis (DM). Methods: We compared the clinical features and short‐term prognoses of 30 DM patients whose serological status included these MSAs. The MSAs were determined by immunoprecipitation. Results: Anti‐155/140 Abs (n = 5), anti‐140 Abs (n = 8), and anti‐ARS Abs (n = 7) did not overlap each other. All of the anti‐155/140 Ab‐positive patients (n = 5) were complicated by malignancies, as were all of the anti‐140 Ab‐positive patients (n = 8), who showed rapidly progressive interstitial lung disease (ILD). The survival rate at 6 months from the diagnosis of DM was significantly lower in the anti‐140 Ab‐positive patients than in the other patients. Conclusion: This is the first study to report, in a single cohort of DM patients, that distinct clinical subsets are distributed in an anti‐155/140 Ab‐positive group, an anti‐140 Ab‐positive group, or an anti‐ARS Ab‐positive group. Our data also confirm previous evidence that anti‐155/140 Abs are involved in malignancies and that anti‐140 Abs are involved in rapidly progressive ILD.