Prominent dermal accumulation of Russell bodies underlying pseudocarcinomatous hyperplasia with fungal infection.

Blockade of the secretion of immunoglobulins leads to their accumulation in plasma cells, resulting in condensed immunoglobulins in the rough endoplasmic reticulum of plasma cells, termed Russell bodies. They are sometimes found in lymphoplasmacellular inflammation of the intestinal mucosa and in lymphoid cell malignancies, but only very rarely in skin diseases. Here, we report an 86-year-old female who presented with a lesion with the prominent accumulation of Russell bodies underlying pseudocarcinomatous hyperplasia with fungal infection in the face. Immunohistochemical staining showed the cells containing Russell bodies to be positive for CD138 and the Russell bodies to be positive for immunoglobulin κ and λ light chains. The present case suggests that when inflammatory cell infiltration with abundant round intracellular eosinophilic materials is observed in the dermis, the dermal accumulation of Russell bodies should be considered in cases with reactive pseudocarcinomatous hyperplasia with fungal infection.

Two novel anti-aminoacyl tRNA synthetase antibodies: Autoantibodies against cysteinyl-tRNA synthetase and valyl-tRNA synthetase.

Anti-aminoacyl-tRNA synthetase (anti-ARS) antibodies are useful for identifying a clinical subset of patients with inflammatory myopathies. Since the myositis of anti-ARS-positive patients is characterized by a unique set of non-myopathic manifestations, including interstitial lung disease, mechanic's hands, and arthralgia, the patients are classified as having anti-synthetase syndrome. Autoantibodies have been identified to eight kinds of ARSs. Of the other 12 ARSs, eight are components of the "OJ" multi-synthetase complex. Autoantibodies to the four remaining ARSs (CysARS, ValARS, SerARS, and TrpARS) have not been reported to be present in patients with inflammatory myopathies. In this study, we first screened samples from more than 300 Japanese patients majorly consisting of those with dermatomyositis (DM) by our established in-house ELISA to find autoantibodies against the four ARSs described above. Since sera from two DM patients specifically reacted to CysARS or ValARS, we determined their reactivities by immunoprecipitation (IP) with the corresponding recombinant proteins and IP-Western blotting with cellular extract. One patient had several features found in anti-synthetase syndrome, but the other did not. The clinical differences among the various anti-ARS antibodies should be explored in a future work.

Immune recognition of lysyl-tRNA synthetase and isoleucyl-tRNA synthetase by anti-OJ antibody-positive sera.

OBJECTIVE: Anti-aminoacyl-tRNA synthetase (anti-ARS) antibodies are useful for identifying a clinical subset of patients with idiopathic inflammatory myopathies (IIMs). Anti-OJ antibodies, which recognize multi-enzyme synthetase complexes including isoleucyl-tRNA synthetase (IARS) and lysyl-tRNA synthetase (KARS), are among the anti-ARS antibodies. Although testing antibodies to other ARSs have been used clinically, no validated immunoassays for detecting anti-OJ antibodies are available. We aimed to establish an anti-OJ ELISA. METHODS: Serum samples were collected from 279 patients with IIMs and 22 patients with idiopathic interstitial pneumonia. Sixty-four of the samples that had been confirmed to be negative for anti-OJ by standard immunoprecipitation were used as the negative control, and 12 anti-OJ-positive reference sera were used as the positive control. Antibodies to IARS and KARS were assayed by ELISA using biotinylated recombinant proteins generated by in vitro transcription/translation. RESULTS: The anti-OJ-positive sera strongly reacted with the KARS and IARS recombinant proteins in ELISA. Although all 12 reference sera were positive in the anti-KARS ELISA, 4 of the 64 anti-OJ-negative sera were also weakly positive. The sensitivity and the specificity were 100% and 93.8%, respectively. Since our anti-KARS ELISA performed well, showing a high agreement with the results for immunoprecipitation (Cohen's κ > 0.8), the remaining 237 samples were also tested. Thirteen anti-KARS-positive sera were newly found by ELISA, all of which were anti-OJ positive by immunoprecipitation. CONCLUSION: Immunoassays for detecting anti-OJ antibodies using KARS and IARS recombinant proteins were developed. Our ELISAs performed well, with very high agreement of the results by immunoprecipitation and can be applied to the first reliable, easy-to-use measurement assays for anti-OJ antibodies.

Strong correlation between cancer progression and anti-transcription intermediary factor 1γ antibodies in dermatomyositis patients.

OBJECTIVES: Transcription intermediary factor 1γ (ΤΙF1γ) protein is known as a tumour suppressor that promotes cellular differentiation. Autoantibodies to ΤΙF1γ have a strong clinical association with cancers associated with dermatomyositis (DM). This study aims to identify the clinical characteristics of cancers in anti-ΤΙF1γ antibody-positive adult patients with DM. METHODS: This retrospective analysis covered 160 adult DM patients who visited Nagoya University Hospital or collaborating medical centres between 2003 and 2016. Anti-TIF1γ antibody and other myositis-specific autoantibodies were detected by ELISA. Based on a review of medical charts, the cancers were staged according to the TNM Classification of Malignant Tumours of the Union for International Cancer Control and were divided into the two groups of "advanced" or "non-advanced" according to the stage classification. RESULTS: Forty-one of the 160 (26%) patients had cancer. The incidence was significantly higher in the anti-TIF1γ-positive patients than in the anti-TIF1γ-negative patients (23/34=68% vs. 18/126=14%, p<1x10-6). Anti-TIF1γ-positive patients with cancer were found more frequently in the "advanced" group than in the "non-advanced" group (21/23=91% vs. 9/18=50%, p<0.0046). The intervals between DM diagnosis and cancer diagnosis were significantly shorter in the anti-TIF1γ-positive patients than in the anti-TIF1γ-negative patients (p=0.047). CONCLUSIONS: Not only did anti-TIF1γ antibodies correlate strongly with malignancy in DM patients, but cancers were also significantly more advanced in anti-TIF1γ-positive DM patients than in anti-TIF1γ-negative patients. Cancers in such cases were very frequently found close to the time of the DM diagnosis.

The majority of generalized pustular psoriasis without psoriasis vulgaris is caused by deficiency of interleukin-36 receptor antagonist.

Generalized pustular psoriasis (GPP) is a rare inflammatory skin disease that can be life-threatening. Recently, it has been reported that familial GPP is caused by homozygous or compound heterozygous mutations of IL36RN. However, the majority of GPP cases are sporadic and it is controversial whether IL36RN mutations are a causative/predisposing factor for sporadic GPP. We searched for IL36RN mutations in two groups of GPP patients in the Japanese population in this study: GPP without psoriasis vulgaris (PV), and GPP with PV. Eleven cases of GPP without PV (GPP alone) and 20 cases of GPP accompanied by PV (GPP with PV) were analyzed. Surprisingly, 9 out of 11 cases of GPP alone had homozygous or compound heterozygous mutations in IL36RN. In contrast, only 2 of 20 cases of GPP with PV had compound heterozygous mutations in IL36RN. The two cases of GPP with PV who had compound heterozygous mutations in IL36RN are siblings, and both cases had PV-susceptible HLA-A*0206. We determined that GPP alone is a distinct subtype of GPP and is etiologically distinguished from GPP with PV, and that the majority of GPP alone is caused by deficiency of the interleukin-36 receptor antagonist due to IL36RN mutations.