Correlation of antinuclear antibody and anti-double-stranded DNA antibody with clinical response to infliximab in patients with rheumatoid arthritis: a retrospective clinical study

[Introduction]The induction of antinuclear antibodies (ANAs) or anti-double-stranded (ds) -DNA antibodies (Abs) after infliximab (IFX) therapy in rheumatoid arthritis (RA) is a well-known phenomenon, but the correlation of such Abs with the clinical response to IFX has not yet been determined. The aims of this retrospective observational study were to examine the prevalence of positive ANA and anti-ds-DNA Abs before and after IFX therapy in patients with RA and to investigate whether an increased titer of such Abs is associated with the clinical efficacy of IFX. [Methods]One hundred eleven RA patients who had received IFX were studied. ANA (indirect immunofluorescence with HEp-2 cells) and anti-ds-DNA Abs (Farr assay) results were examined before and after IFX therapy. [Results]The overall clinical response assessed by EULAR response criteria was as follows: good response in 55%, including remission in 38%; moderate response in 18%; and no response (NOR) in 27%. The positivity of ANA (≥ 1:160) and anti-ds-DNA Abs significantly increased from 25% to 40% (P = 0.03) and from 3% to 26% (P < 0.001) after IFX, respectively. EULAR response differed significantly according to the ANA titer before IFX (P = 0.001), and the efficacy of IFX became worse as the ANA titer before starting IFX increased. Furthermore, the differences in the clinical response of the ANA titer before IFX ≤ 1:80 and ≥ 1:160 were significant (good, moderate, and no response were 66%, 9%, and 25% in ≤ 1:80 group versus 26%, 33%, 41% in ≥ 1:160 group, respectively; P < 0.001). In 13 patients whose ANA had increased after IFX, 10 showed NOR, only one showed a good response, and none reached remission. These clinical responses were significantly different from ANA no-change patients. In 21 patients with positive anti-ds-DNA Abs after IFX, 16 showed NOR, only two showed a good response, and none reached remission. [Conclusions]The present study suggests that the ANA titer before starting IFX predicts the clinical response to IFX. The increased titers of ANA or anti-ds-DNA Abs after IFX may be useful markers of NOR

Prevalence and predictors of direct discharge home following hospitalization of patients with serious adverse events managed by the rapid response system in Japan: a multicenter, retrospective, observational study

Aim: The rapid response system (RRS) is an in-hospital medical safety system. To date, not much is known about patient disposition after RRS activation, especially discharge home. This study aimed to investigate the prevalence, characteristics, and outcomes of patients with adverse events who required RRS activation. Methods: Retrospective data from the In-Hospital Emergency Registry in Japan collected from April 2016 to November 2020 were eligible for our analysis. We divided patients into Home Discharge, Transfer, and Death groups. The primary outcome was the prevalence of direct discharge home, and independently associated factors were determined using multivariable logistic regression. Results: We enrolled 2,043 patients who met the inclusion criteria. The prevalence of discharge home was 45.7%; 934 patients were included in the Home Discharge group. Age (adjusted odds ratio [AOR] 0.96; 95% confidence interval [CI], 0.95-0.97), malignancy (AOR 0.69; 95% CI, 0.48-0.99), oxygen administration before RRS (AOR 0.49; 95% CI, 0.36-0.66), cerebral performance category score on admission (AOR 0.38; 95% CI, 0.26-0.56), do not attempt resuscitation order before RRS (AOR 0.17; 95% CI, 0.10-0.29), RRS call for respiratory failure (AOR 0.50; 95% CI, 0.34-0.72), RRS call for stroke (AOR 0.12; 95% CI, 0.03-0.37), and intubation (AOR 0.20; 95% CI, 0.12-0.34) were independently negative, and RRS call for anaphylaxis (AOR 15.3; 95% CI, 2.72-86.3) was positively associated with discharge home. Conclusion: Less than half of the in-hospital patients under RRS activation could discharge home. Patients' conditions before RRS activation, disorders requiring RRS activation, and intubation were factors that affected direct discharge home

Overexpression of a Minimal Domain of Calpastatin Suppresses IL-6 Production and Th17 Development via Reduced NF-κB and Increased STAT5 Signals

Calpain, a calcium-dependent cysteine protease, is reportedly involved in the pathophysiology of autoimmune diseases such as rheumatoid arthritis (RA). In addition, autoantibodies against calpastatin, a natural and specific inhibitor of calpain, are widely observed in RA. We previously reported that E-64-d, a membrane-permeable cysteine protease inhibitor, is effective in treating experimental arthritis. However, the exact role of the calpastatin-calpain balance in primary inflammatory cells remains unclear. Here we investigated the effect of calpain-specific inhibition by overexpressing a minimal functional domain of calpastatin in primary helper T (Th) cells, primary fibroblasts from RA patients, and fibroblast cell lines. We found that the calpastatin-calpain balance varied during Th1, Th2, and Th17 development, and that overexpression of a minimal domain of calpastatin (by retroviral gene transduction) or the inhibition of calpain by E-64-d suppressed the production of IL-6 and IL-17 by Th cells and the production of IL-6 by fibroblasts. These suppressions were associated with reductions in RORγt expression and STAT3 phosphorylation. Furthermore, inhibiting calpain by silencing its small regulatory subunit (CPNS) suppressed Th17 development. We also confirmed that overexpressing a minimal domain of calpastatin suppressed IL-6 by reducing NF-κB signaling via the stabilization of IκBα, without affecting the upstream signal. Moreover, our findings indicated that calpastatin overexpression suppressed IL-17 production by Th cells by up-regulating the STAT5 signal. Finally, overexpression of a minimal domain of calpastatin suppressed IL-6 production efficiently in primary fibroblasts derived from the RA synovium. These findings suggest that inhibiting calpain by overexpressing a minimal domain of calpastatin could coordinately suppress proinflammatory activities, not only those of Th cells but also of synovial fibroblasts. Thus, this strategy may prove viable as a candidate treatment for inflammatory diseases such as RA

Serum IgG levels demonstrate seasonal change in connective tissue diseases: a large-scale, 4-year analysis in Japanese.

Hypergammaglobulinemia is often found in patients with autoimmune diseases, such as systemic lupus erythematosus (SLE), and its level may correlate with disease activity. However, it is unclear whether immunoglobulin G (IgG) displays seasonal changes. We analyzed the seasonal change in serum IgG by assessing 450 patients with connective tissue disease. The serum IgG levels in summer were compared with those in winter from 2006 to 2009. Independent samples from 355 patients were analyzed to confirm results in the first set. The differences in the IgG levels between the two seasons were analyzed in each disease and compared with disease activity. 488 patients without connective tissue disease were analyzed as reference instead of healthy people as control. We found that connective tissue disease patients tended to show higher levels of serum IgG in summer than in winter every year from 2006 to 2009, whereas patients without connective tissue disease did not demonstrate such a tendency. We observed this seasonal tendency in each disease. Seasonal changes weakly correlated with those of anti-DNA antibody in SLE patients and those of disease activity score in rheumatoid arthritis (RA) patients. Serum IgG levels of patients with connective tissue diseases display seasonal variations. Biological and clinical significance of these variations should be elucidated

Anti-U1 RNP antibodies in cerebrospinal fluid are associated with central neuropsychiatric manifestations in systemic lupus erythematosus and mixed connective tissue disease.

[Objective]To determine the significance of anti–U1 RNP antibodies in the cerebrospinal fluid (CSF) of patients with systemic lupus erythematosus (SLE) or mixed connective tissue disease (MCTD) who have central neuropsychiatric SLE (NPSLE). [Methods]The frequency of antinuclear antibodies including anti–U1 RNP antibodies in the sera and CSF of 24 patients with SLE and 4 patients with MCTD, all of whom had neuropsychiatric syndromes, was determined using an RNA immunoprecipitation assay and an enzyme-linked immunosorbent assay. The frequency of anti–U1 RNP antibodies in the CSF of patients with central NPSLE was examined, and the anti–U1 RNP index ([CSF anti–U1 RNP antibodies/serum anti–U1 RNP antibodies]/[CSF IgG/serum IgG]) was compared with CSF interleukin-6 (IL-6) levels and the albumin quotient (Qalb, an indicator of blood–brain barrier damage). CSF and serum antibodies against U1-70K, U1-A, and U1-C, including autoantigenic regions, were examined, and the U1-70K, U1-A, and U1-C indices as well as the anti–U1 RNP index were calculated. [Results]CSF anti–U1 RNP antibodies with an increased anti–U1 RNP index showed 64.3% sensitivity and 92.9% specificity for central NPSLE. The anti–U1 RNP index did not correlate with CSF IL-6 levels or the Qalb. The anti–U1-70K index was higher than the anti–U1-A and anti–U1-C indices in the CSF of anti–U1 RNP antibody–positive patients with central NPSLE. The major autoantigenic region for CSF anti–U1-70K antibodies appeared to be localized in U1-70K amino acid 141–164 residue within the RNA-binding domain. [Conclusion]The frequency of anti–U1 RNP antibodies in the CSF and the anti–U1 RNP index are useful indicators of central NPSLE in anti–U1 RNP antibody–positive patients. The predominance of anti–U1-70K antibodies in CSF suggests intrathecal anti–U1 RNP antibody production

NEFA/nucleobindin-2 is a target autoantigen of the anti-Wa antibody and is associated with transfer RNA.

[Objectives]: The anti-Wa antibody found in systemic sclerosis patients reacts with a transfer RNA (tRNA)-associated 48-kDa protein and immunoprecipitates several tRNAs. We investigated the Wa antigen and its binding to tRNA species. [Methods]: We performed molecular cloning of the Wa antigen and made its recombinant protein. To investigate Wa antigen distribution in the cell, we performed an indirect immunofluorescence study. To determine the Wa-bound tRNA species, we performed a reverse transcription (RT)-polymerase chain reaction (PCR) using the RNAs immunoprecipitated by anti-Wa antibody as templates, and synthetic primers of mammalian tRNA sequences. To clarify the tissue expression of Wa antigen, we performed quantitative and semi-quantitative PCR of the cDNA. [Results]: We demonstrated that the Wa antigen was identical to NEFA (DNA binding/EF-hand/acidic amino acid rich region), otherwise known as nucleobindin-2. A full-length and an alternative splice variant cDNA lacking exon 11 were isolated by cloning NEFA cDNA. Anti-Wa-positive sera stained both the nucleus and cytoplasm of HEp-2 cells. RT-PCR suggested that Wa binds at least six tRNA species. In human tissues, NEFA is expressed predominantly in exocrine glands. [Conclusions]: We have demonstrated that the Wa antigen is NEFA or nucleobindin-2, which binds specific tRNA species, and is distributed in specific human tissues