Objective. To determine the range of antinuclear antibodies (ANA) in “healthy” individuals compared with that in patients with systemic lupus erythematosus (SLE), systemic sclerosis (SSc; scleroderma), Sjögren's syndrome (SS), rheumatoid arthritis (RA), or soft tissue rheumatism (STR). Methods. Fifteen international laboratories experienced in performing tests for ANA by indirect immunofluorescence participated in analyzing coded sera from healthy individuals and from patients in the 5 different disease groups described above. Except for the stipulation that HEp‐2 cells should be used as substrate, each laboratory used its own in‐house methodology so that the data might be expected to reflect the output of a cross‐section of worldwide ANA reference laboratories. The sera were analyzed at 4 dilutions: 1:40, 1:80, 1:160, and 1:320. Results. In healthy individuals, the frequency of ANA did not differ significantly across the 4 age subgroups spanning 20–60 years of age. This putatively normal population was ANA positive in 31.7% of individuals at 1:40 serum dilution, 13.3% at 1:80, 5.0% at 1:160, and 3.3% at 1:320. In comparison with the findings among the disease groups, a low cutoff point at 1:40 serum dilution (high sensitivity, low specificity) could have diagnostic value, since it would classify virtually all patients with SLE, SSc, or SS as ANA positive. Conversely, a high positive cutoff at 1:160 serum dilution (high specificity, low sensitivity) would be useful to confirm the presence of disease in only a portion of cases, but would be likely to exclude 95% of normal individuals. Conclusion. It is recommended that laboratories performing immunofluorescent ANA tests should report results at both the 1:40 and 1:160 dilutions, and should supply information on the percentage of normal individuals who are positive at these dilutions. A low‐titer ANA is not necessarily insignificant and might depend on at least 4 specific factors. ANA assays can be a useful discriminant in recognizing certain disease conditions, but can create misunderstanding when the limitations are not fully appreciated.

Systemic lupus erythematosus (SLE) is a multisystem, autoimmune disease that predominantly affects women. Previous findings that duplicated Toll-like receptor 7 (Tlr7) promotes lupus-like disease in male BXSB mice prompted us to evaluate TLR7 in human SLE. By using a candidate gene approach, we identified and replicated association of a TLR7 3′UTR SNP, rs3853839 (G/C), with SLE in 9,274 Eastern Asians (P combined = 6.5 × 10 −10 ), with a stronger effect in male than female subjects [odds ratio, male vs. female = 2.33 (95% CI = 1.64-3.30) vs. 1.24 (95% CI = 1.14-1.34); P = 4.1 × 10]. G-allele carriers had increased TLR7 transcripts and more pronounced IFN signature than C-allele carriers; heterozygotes had 2.7-fold higher transcripts of G-allele than C-allele. These data established a functional polymorphism in type I IFN pathway gene TLR7 predisposing to SLE, especially in Chinese and Japanese male subjects. functional polymorphism | disease susceptibility | autoimmunity | type I interferon S ystemic lupus erythematosus [SLE; Online Mendelian Inheritance in Man (OMIM) no. 152700] is a multisystem, autoimmune disease with strong genetic and environmental components (1). SLE predominantly affects women, with a female-to-male ratio of approximately 9:1. Male patients with SLE, although rare, tend to have more severe disease and poorer outcome (2), suggesting potential sex dimorphism in the disease development. Although the sex effect has often been attributed to sex hormones, the fact that XXY male subjects have approximately a 14-fold higher risk of developing SLE than 46 XY men indicates that X-linked genes may be risk factors for human SLE (3).Located at Xp22.2, Toll-like receptor 7 (TLR7; OMIM no. 300365) and its functionally related gene TLR8 (OMIM no. 300366) encode proteins that play critical roles in pathogen recognition and activation of innate immunity (4). They recognize endogenous RNA-containing autoantigens and induce the expression of type I IFN, a pivotal cytokine in the pathogenesis of SLE (5). In lupus-prone BXSB mice, the translocation of a segmental duplication of X chromosome to Y chromosome creates the Y-linked autoimmune accelerator (Yaa) locus, which was associated with autoreactive B cell responses to RNA-related antigens and exacerbation of glomerulonephritis in male mice (6). Although translocated X chromosome segment in Yaa may contain as many as 16 genes, the major gene for causation of the autoimmune phenotypes was identified to be TLR7 (7), making it a potential susceptibility gene for SLE. By using a candidate gene approach, we report herein that a functional polymorphism in 3′UTR of TLR7 is associated with SLE in Chinese and Japanese populations, with a stronger effect in male than female subjects. ResultsDiscovery and Replication of the Association of a TLR7 3′UTR SNP with SLE in Eastern Asian Population. We genotyped 27 SNPs from the TLR7-TLR8 region (12 in TLR7 and 15 in TLR8) in 1,434 SLE cases and 1,591 control subjects of Eastern Asian ancestry using the Beadstation Infinium II...

Objective. Autoantibodies against DFS70 (dense fine speckles 70) antigen (also known as lens epithelium-derived growth factor) have been recently identified among the antinuclear antibodies (ANAs) in patients with atopic disorders. We undertook this study to examine the frequency of anti-DFS70 antibodies in a large number of healthy people.Methods. Sera of 597 healthy individuals working in a hospital (142 men, 455 women) were analyzed for ANAs and for anti-DFS70 antibodies by indirect immunofluorescence (IIF) with HEp-2 cells as a substrate and by immunoblotting using DFS70 recombinant protein and whole HeLa cell extract.Results. ANAs were present in 20% of all individuals by IIF. Nine percent of subjects were ANA positive at a serum dilution of 1:40, 4.0% at 1:80, 5.5% at 1:160, 1.0% at 1:320, and 0.3% at 1:640. There were 64 anti-DFS70 antibody-positive individuals. Surprisingly, this was 11% of the whole population and 54% of the ANA-positive population. The percentage of female anti-DFS70 antibody-positive subjects (86%; 55 of 64 subjects) was higher than the percentage of female anti-DFS70 antibody-negative subjects (75%; 398 of 533 subjects) (P < 0.05). The prevalence of anti-DFS70 antibody-positive sera decreased with increasing age (P ‫؍‬ 0.0017).Conclusion. Considering that anti-DFS70 antibody positivity is rare in patients with systemic autoimmune diseases, introducing the anti-DFS70 antibody examination as a screening test for ANA-positive persons could be used to rule out systemic autoimmune diseases, resulting in considerable cost-saving potential. In addition, this test defines a subpopulation of healthy people in whom long-term followup might reveal healthrelated implications of this finding, since anti-DFS70 antibodies have been shown to be associated with some illnesses.

IntroductionWe investigated the clinical and serological features of patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) in Japan using data from a nationwide, prospective, inception cohort study.MethodsIn total, 156 Japanese patients with newly diagnosed AAV were classified according to the European Medicines Agency (EMEA) algorithm with exploratory surrogate markers for AAV-related non-granulomatous pulmonary lesions, predefined as alveolar haemorrhage and interstitial lung disease (ILD), and their clinical and serological features were evaluated.ResultsUsing the EMEA algorithm, we identified 14 patients (9.0%) with eosinophilic granulomatosis with polyangiitis (EGPA), 33 (21.2%) with granulomatosis with polyangiitis (GPA), 78 (50.0%) with microscopic polyangiitis and renal-limited vasculitis (MPA/RLV), and 31 (19.9%) with unclassifiable vasculitis. The average ages of patients with EGPA (male/female, 5/9), GPA (12/21), and MPA/RLV (35/43) and unclassifiable (9/22) were 58.0, 63.6, 71.1, and 70.6 years, respectively. Myeloperoxidase (MPO)-ANCA and proteinase-3 ANCA positivity was 50.0% and 0% for EGPA, 54.6% and 45.5% for GPA, 97.4% and 2.6% for MPA/RLV, and 93.5% and 3.2% for unclassifiable, respectively. According to the Birmingham Vasculitis Activity Score (BVAS), cutaneous (71.4%) and nervous system (92.9%) manifestations were prominent in EGPA and ear, nose, and throat manifestations (84.9%) and chest manifestations (66.7%) in GPA. Renal manifestations developed frequently in MPA/RLV (91.0%) and GPA (63.6%). The average serum creatinine levels were 0.71 mg/dL for EGPA, 1.51 mg/dL for GPA, 2.46 mg/dL for MPA/RLV, and 0.69 mg/dL for unclassifiable. The percentages of patients with ILD were 14.3% for EGPA, 9.0% for GPA, 47.4% for MPA/RLV, and 61.3% for unclassifiable. Patients with ILD (n = 61) had significantly lower BVAS (P = 0.019) with fewer ear, nose, and throat and cardiovascular manifestations than patients without ILD (n = 95).ConclusionsMPO-ANCA-positive MPA/RLV is the most common form of AAV in Japanese patients, and one-half of patients with GPA were positive for MPO-ANCA. ILD is an important clinical manifestation in Japanese patients with AAV. Unclassifiable vasculitis with MPO-ANCA positivity and ILD may represent a novel variant of MPA.Trial RegistrationThe University Hospital Medical Information Network Clinical Trials Registry: UMIN000001648. Registered 28 February 2009.

A nuclear antigen associated with cell proliferation (proliferating cell nuclear antigen-PCNA) and blast transformation is recognized by autoantibodies in the sera of some patients with systemic lupus erythematosus. This autoantibody is a precipitating antibody and also reacts in immunofluorescence, staining the nucleoplasm of proliferating and blast-transformed cells. The autoantibody was used as a reagent to determine the distribution of PCNA in a synchronized continuous B lymphoid cell line (WiL-2) and in mitogen-induced blast-transformed lymphocytes. In WiL-2 cells, PCNA was detected as speckled nucleoplasmic staining in G1, S, and G2 phases of the cell cycle. In addition, during late G1 and early S phases, PCNA was also detected in the nucleolus. During mitogen-induced blast transformation of lymphocytes, PCNA was noticed in the nucleolus before the initiation of DNA synthesis and later became nucleoplasmic with disappearance of nucleolar staining. These studies demonstrate that the relationship of PCNA to proliferation and blast transformation may be associated with events related to DNA synthesis in these cells.