Epstein-barr virus infections induce aberrant osteoclastogenesis in immune system-humanized NOD/Shi-scid/IL-2RγCnull mice.

Epstein-Barr virus (EBV) and other viral infections are possible triggers of autoimmune diseases, such as rheumatoid arthritis (RA). To analyze the causative relationship between EBV infections and RA development, we performed experiment on humanized NOD/Shi-scid/IL-2RγCnull (hu-NOG) mice reconstituted human immune system components and infected with EBV. In EBV-infected hu-NOG mice, breakdown of knee joint bones was found to be accompanied by the accumulation of receptor activator of nuclear factor-κB (NF-κB) (RANK) ligand (RANKL), a key factor in osteoclastogenesis, human CD19 and EBV-encoded small RNA (EBER)-bearing cells. Accumulation of these cells expanded in the bone marrow adjacent to the bone breakage, showing a histological feature like to that in bone marrow edema. On the other hand, human RANK/human matrix metalloprotease-9 (MMP-9) positive, osteoclast-like cells were found at broken bone portion of EBV-infected mouse knee joint. In addition, human macrophage-colony stimulating factor (M-CSF), an essential factor in development of osteoclasts, evidently expressed in spleen and bone marrow of EBV-infected humanized mice. Furthermore, RANKL and M-CSF were identified at certain period of EBV-transformed B lymphoblastoid cells (BLBCs) derived from umbilical cord blood lymphocytes. Co-culturing bone marrow cells of hu-NOG mice with EBV-transformed BLBCs resulted in the induction of a multinucleated cell population positive for tartrate-resistant acid phosphatase and human MMP-9 which indicating human osteoclast-like cells. These findings suggest that EBV-infected BLBCs induce human aberrant osteoclastogenesis, which cause erosive arthritis in the joints.

Risk factors associated with relapse after methotrexate dose reduction in patients with rheumatoid arthritis receiving golimumab and methotrexate combination therapy.

AIM: To identify risk factors for relapse after methotrexate (MTX) dose reduction in rheumatoid arthritis (RA) patients receiving golimumab (GLM)/MTX combination therapy. METHOD: Data on RA patients ≥20 years old receiving GLM (50 mg) + MTX for ≥6 months were retrospectively collected. MTX dose reduction was defined as a reduction of ≥12 mg from the total dose within 12 weeks of the maximum dose (≥1 mg/wk average). Relapse was defined as Disease Activity Score in 28 joints using C-reactive protein level (DAS28-CRP) score ≥3.2 or sustained (≥ twice) increase of ≥0.6 from baseline. RESULTS: A total of 304 eligible patients were included. Among the MTX-reduction group (n = 125), 16.8% of patients relapsed. Age, duration from diagnosis to the initiation of GLM, baseline MTX dose, and DAS28-CRP were comparable between relapse and no-relapse groups. The adjusted odds ratio (aOR) of relapse after MTX reduction was 4.37 (95% CI 1.16-16.38, P = 0.03) for prior use of non-steroidal anti-inflammatory drugs (NSAIDs), and the aORs for cardiovascular disease (CVD), gastrointestinal disease and liver disease were 2.36, 2.28, and 3.03, respectively. Compared to the non-reduction group, the MTX-reduction group had a higher proportion of patients with CVD (17.6% vs 7.3%, P = 0.02) and a lower proportion of prior use of biologic disease-modifying antirheumatic drugs (11.2% vs. 24.0%, P = 0.0076). CONCLUSION: Attention should be given to RA patients with history of CVD, gastrointestinal disease, liver disease, or prior NSAIDs-use when considering MTX dose reduction to ensure benefits outweigh the risks of relapse.

Anti-neutrophil Cytoplasmic Antibody-negative Eosinophilic Granulomatosis with Polyangiitis Complicated with Peripheral Neuropathy that Underwent Remission Induction with Mepolizumab Monotherapy.

A 72-year-old woman was admitted to our hospital with numbness in her lower extremities and hypereosinophilia. She was diagnosed with eosinophilic granulomatosis with polyangiitis (EGPA). On admission, she was suspected of being complicated with pneumonia and sepsis; therefore, treatment with mepolizumab monotherapy was begun, resulting in partial improvement. After the possibility of a complicating infection was ruled out, corticosteroids were initiated, followed by intravenous gamma globulin therapy. Although the induction of remission of EGPA with mepolizumab monotherapy is not usually recommended, induction with mepolizumab monotherapy may be an option in terms of safety and clinical efficacy in some cases.

Are Viral Infections Key Inducers of Autoimmune Diseases? Focus on Epstein-Barr Virus.

It is generally accepted that certain viral infections can trigger the development of autoimmune diseases. However, the exact mechanisms by which these viruses induce autoimmunity are still not understood. In this review, we first describe hypothetical mechanisms by which viruses induce some representative autoimmune diseases. Then, we focus on Epstein-Barr virus (EBV) and discuss its role in the pathogenesis of rheumatoid arthritis (RA). The discussion is mainly based on our own previous findings that (A) EBV DNA and its products EBV-encoded small RNA (EBER) and latent membrane protein 1 (LMP1) are present in the synovial lesions of RA, (B) mRNA expression of the signaling lymphocytic activation molecule-associated protein (SAP)/SH2D1A gene that plays a critical role in cellular immune responses to EBV is reduced in the peripheral T cells of patients with RA, and (C) EBV infection of mice reconstituted with human immune system components (humanized mice) induced erosive arthritis that is pathologically similar to RA. Additionally, environmental factors may contribute to EBV reactivation as follows: Porphyromonas gingivalis peptidylarginine deiminase (PAD), an enzyme required for citrullination, engenders antigens leading to the production of citrullinated peptides both in the gingiva and synovium. Anti-citrullinated peptides autoantibody is an important marker for diagnosis and disease activity of RA. These findings, as well as various results obtained by other researchers, strongly suggest that EBV is directly involved in the pathogenesis of RA, a typical autoimmune disease.

Successful treatment for eosinophilic granulomatosis with polyangiitis causing severe myocarditis followed by cardiac magnetic resonance.

A 38-year-old woman had a history of asthma for 20 years. Bullous lesions had appeared on her left side of the back. Two months before admission, the biopsy revealed eosinophilic cellulitis. One month later, she experienced numbness in both legs. She was admitted to our hospital for emergency treatment due to chest pain and loss of consciousness. Emergency coronary angiography revealed triple-vessel vasospasm. She had cardiac arrest for 4 min during the examination. We suspected eosinophilic granulomatosis with polyangiitis due to pulmonary infiltrate, eosinophilia, and a history of illness. We, therefore, started methylprednisolone pulse therapy. Although her condition and laboratory findings improved, cardiac magnetic resonance (CMR) imaging performed on day 16 showed myocardial oedema and myocardial fibrosis on late gadolinium enhancement. Coronary angiography on day 35 revealed no spasm, and myocardial biopsy showed the absence of vasculitis. There was no improvement in myocardial oedema. CMR showed enlargement of late gadolinium enhancement and formation of a ventricular aneurysm. As myocarditis did not improve sufficiently, five courses of intravenous cyclophosphamide pulse therapy were administered. CMR on day 152 showed the disappearance of myocardial oedema. We report a unique case of successful treatment of severe myocarditis and the usefulness of follow-up CMR.

Successful Treatment of SARS-CoV-2 Vaccination-related Activation of Rheumatoid Arthritis with Positive Findings for Epstein-Barr Virus.

We herein report a 60-year-old woman who experienced severe flare of rheumatoid arthritis (RA) and Epstein-Barr virus (EBV) positivity following administration of the messenger ribonucleic acid (mRNA)-type severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine. Since 40 years old, she had been in long-term remission of anti-citrullinated protein antibody-positive RA. Ten days after SARS-CoV-2 vaccination, she presented with a high fever and polyarthritis, active synovitis on joint ultrasound, a clinical disease activity index of 35, and positivity for anti-early antigen, diffuse type and restricted type (EA DR) IgG and EBV deoxyribonucleic acid (EBV-DNA). Tocilizumab was introduced to treat RA. The RA disease activity disappeared, and anti-EA DR IgG and EBV-DNA became negative.

Does HTLV-1 Infection Show Phenotypes Found in Sjögren's Syndrome?

Viruses are a possible cause for Sjögren's syndrome (SS) as an environmental factor related to SS onset, which exhibits exocrine gland dysfunction and the emergence of autoantibodies. Although retroviruses may exhibit lymphocytic infiltration into exocrine glands, human T-cell leukemia virus type 1 (HTLV-1) has been postulated to be a causative agent for SS. Transgenic mice with HTLV-1 genes showed sialadenitis resembling SS, but their phenotypic symptoms differed based on the adopted region of HTLV-1 genes. The dominance of tax gene differed in labial salivary glands (LSGs) of SS patients with HTLV 1-associated myelopathy (HAM) and adult T-cell leukemia. Although HTLV-1 was transmitted to salivary gland epithelial cells (SGECs) by a biofilm-like structure, no viral synapse formation was observed. After infection to SGECs derived from SS patients, adhesion molecules and migration factors were time-dependently released from infected SGECs. The frequency of the appearance of autoantibodies including anti-Ro/SS-A, La/SS-B antibodies in SS patients complicated with HAM is unknown; the observation of less frequent ectopic germinal center formation in HTLV-1-seropositive SS patients was a breakthrough. In addition, HTLV-1 infected cells inhibited B-lymphocyte activating factor or C-X-C motif chemokine 13 through direct contact with established follicular dendritic cell-like cells. These findings show that HTLV-1 is directly involved in the pathogenesis of SS.

Involvement of Epstein-Barr virus in the development and spontaneous regression of methotrexate-associated lymphoproliferative disorder in patients with rheumatoid arthritis.

OBJECTIVES: Conventionally, some patients with methotrexate-associated lymphoproliferative disorder (MTX-LPD) undergo spontaneous tumour regression after cessation of MTX. Although the involvement of Epstein-Barr virus (EBV) in the development and spontaneous regression has been suggested, the underlying mechanism remains unknown. In this study, we analysed patients who had developed MTX-LPD to evaluate the association between the development and spontaneous regression of MTX-LPD with EBV. METHODS: We analysed the age, stage, disease activity, MTX dose, lymphocyte count, EBV real-time polymerase chain reaction (PCR) test value, and EBV-encoded small RNA (EBER) positivity rate in patients with MTX-LPD at our hospital. Moreover, we investigated the factors related to spontaneous regression, which is a characteristic of MTX-LPD. RESULTS: Thirty-four patients were enrolled in this study. The MTX dose at LPD onset was 8.3±2.0 mg/week, and the total dose of MTX was 1,530.3±779.2 mg. The EBV load in the peripheral blood was 270.4±431.8 copy/µL, and the pathological tissues of 17 of 34 (50%) patients tested positive for EBER. Twenty-one patients had spontaneous regression after discontinuation of MTX. The factors related to spontaneous regression were examined using a univariate analysis, and the EBV real-time PCR test value in the peripheral blood, EBER in pathological tissues, and improvement rate of lymphocyte count were considered significant factors. The EBV real-time PCR test value in the peripheral blood was defined as an independent factor of spontaneous regression using a multivariate analysis of related factors. CONCLUSIONS: EBV may be involved in the development of MTX-LPD and its spontaneous regression.

Antinuclear antibodies produced in HLA-DR transgenic humanized mice developed chronic graft-versus-host disease.

BACKGROUND: Chronic graft versus host disease (GVHD) has been reported in humanized mice after the implantation of human hematopoietic stem cells (hu-HSC). As such, humanized mice have been applied to a mouse model of chronic GVHD; however, B-cell activation and autoantibody production did not occur, and the clinical features of chronic GVHD were not sufficiently reproduced. The purpose of this study was to establish an improved humanized mouse model with chronic GVHD using HLA-DR transgenic NOD/Shi-scid, IL-2RγKO (NOG) mice. METHODS: CD34-positive cells were isolated from blood extracted from HLA-DRB1∗0405-positive umbilical cords using magnetic cell isolation. Then these were transplanted into NOG-Iab KO, HLA-DR 0405 Tg mice aged 8-16 weeks. GVHD symptoms were observed 26 weeks after transplantation. Histological findings of the skin, lung, liver, and spleen were compared with those of non-humanized mice. Antinuclear antibodies (ANA) were measured by indirect immunofluorescence using sera isolated 26 weeks after transplantation. RESULTS: Although GVHD symptoms were not observed in humanized (hu-HSC) NOG-Iab KO, HLA-DR 0405 Tg mice during the observation period, histological findings of human T-cell infiltration were observed in the skin, liver, and lung, suggesting that GVDH was present; human tingible body macrophages or clusters of BCL-6-positive human B-cells were observed in the spleen. Furthermore, human IgG ANA with peripheral or homogeneous staining patterns were also detected in the sera. CONCLUSION: Hu-HSC NOG-Iab KO, HLA-DR 0405 Tg mice differed from conventional models in terms of B-cell activation and ANA production. This study is the first to report on B-cell activation and autoantibody production in humanized mice with chronic GVHD, suggesting that hu-HSC NOG-Iab KO, HLA-DR 0405 Tg mice could be applied to a new humanized mouse model of chronic GVHD.

Asymptomatic myocardial dysfunction was revealed by feature tracking cardiac magnetic resonance imaging in patients with primary Sjögren's syndrome.

AIM: To evaluate subclinical left ventricular (LV) regional dysfunction in patients with primary Sjögren's syndrome (pSS) using feature tracking cardiac magnetic resonance (FT-CMR) imaging and to identify pSS characteristics independently associated with LV regional dysfunction. METHOD: Fifty patients with pSS and 20 controls without cardiovascular disease underwent non-contrast CMR imaging. Labial gland biopsy was performed in 42 patients (84%). Disease activity was assessed using the European League Against Rheumatism Sjögren's syndrome disease activity index (ESSDAI). LV global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) were measured using FT-CMR. RESULTS: No significant differences in cardiovascular risk factors were found between the pSS group and controls. The pSS group had significantly lower GLS (P = .015) and GCS (P = .008) than the control group. Multiple linear regression analysis indicated that GCS was significantly associated with Raynaud's phenomenon (P = .015), focus score ≥2 (P = .032), and total ESSDAI score ≥8 (P = .029). CONCLUSION: FT-CMR can reveal subclinical LV regional dysfunction in patients with pSS without cardiovascular disease. Furthermore, patients with pSS and Raynaud's phenomenon, a focus score ≥2, or an ESSDAI score ≥8 were considered to be at high risk for myocardial dysfunction.

Successful early introduction of mepolizumab for peripheral neuropathy with a peripheral circulatory disorder in a patient with myeloperoxidase anti-neutrophil cytoplasmic antibody-negative eosinophilic granulomatosis with polyangiitis.

A 26-year-old woman presented with abdominal pain, diarrhoea, vomiting, fever, and progressive paralysis in the lower limbs. She had a history of bronchial asthma and experienced sinusitis, progressive peripheral neuropathy, polyarthritis, and leukocytosis with prominent eosinophilia. The patient was diagnosed with eosinophilic granulomatosis with polyangiitis (EGPA). Abdominal pain was considered to be an ischaemic enteritis associated with EGPA. She was administered 1,000 mg/day of methylprednisolone for 3 days and intravenous immunoglobulin (400 mg/kg/day of γ-globulin for 5 days) followed by 50 mg (1 mg/kg)/day of oral prednisolone due to rapidly progressing peripheral neuropathy. Her symptoms temporarily improved; however, peripheral neuropathy recurred after a week, and the eosinophil count increased. Eighteen days after following the resumed treatment, 300 mg of mepolizumab, a humanised monoclonal antibody, was administered. Subjective symptoms, nerve conduction velocity, and skin perfusion pressure (an index of peripheral circulation in the lower extremities) improved after 4 weeks. Although mepolizumab has been approved for EGPA, there is no evidence of its efficacy against peripheral neuropathy. Early introduction of mepolizumab may contribute to an the early improved progressive peripheral neuropathy with eosinophilia.

Human osteoclastogenesis in Epstein-Barr virus-induced erosive arthritis in humanized NOD/Shi-scid/IL-2Rγnull mice.

Many human viruses, including Epstein-Barr virus (EBV), do not infect mice, which is challenging for biomedical research. We have previously reported that EBV infection induces erosive arthritis, which histologically resembles rheumatoid arthritis, in humanized NOD/Shi-scid/IL-2Rγnull (hu-NOG) mice; however, the underlying mechanisms are not known. Osteoclast-like multinucleated cells were observed during bone erosion in this mouse model, and therefore, we aimed to determine whether the human or mouse immune system activated bone erosion and analyzed the characteristics and origin of the multinucleated cells in hu-NOG mice. Sections of the mice knee joint tissues were immunostained with anti-human antibodies against certain osteoclast markers, including cathepsin K and matrix metalloproteinase-9 (MMP-9). Multinucleated cells observed during bone erosion stained positively for human cathepsin K and MMP-9. These results indicate that human osteoclasts primarily induce erosive arthritis during EBV infections. Human osteoclast development from hematopoietic stem cells transplanted in hu-NOG mice remains unclear. To confirm their differentiation potential into human osteoclasts, we cultured bone marrow cells of EBV-infected hu-NOG mice and analyzed their characteristics. Multinucleated cells cultured from the bone marrow cells stained positive for human cathepsin K and human MMP-9, indicating that bone marrow cells of hu-NOG mice could differentiate from human osteoclast progenitor cells into human osteoclasts. These results indicate that the human immune response to EBV infection may induce human osteoclast activation and cause erosive arthritis in this mouse model. Moreover, this study is the first, to our knowledge, to demonstrate human osteoclastogenesis in humanized mice. We consider that this model is useful for studying associations of EBV infections with rheumatoid arthritis and human bone metabolism.

Salivary Gland Focus Score Is Associated With Myocardial Fibrosis in Primary Sjögren Syndrome Assessed by a Cardiac Magnetic Resonance Approach.

OBJECTIVE: The risk of clinically manifested major cardiovascular (CV) events in primary Sjögren syndrome (pSS) remains unclear. This study aimed to assess myocardial fibrosis in pSS and investigate the associated disease characteristics by cardiac magnetic resonance imaging (cMRI). METHODS: We performed a cross-sectional study of patients with pSS without cardiac symptoms. Labial gland biopsy was documented in 44 patients (85%). Patients without CV risk factors underwent contrast-enhanced cMRI. Late gadolinium enhancement (LGE) was used to assess myocardial fibrosis. Myocardial edema was assessed using T2-weighted imaging (T2WI). We compared the left ventricular (LV) geometry and function between the groups with and without LGE. Further, we explored the associations of cMRI abnormalities with pSS characteristics. RESULTS: Fifty-two women with pSS (median age 55, IQR 47.0-65.7 yrs) were enrolled in the study. LGE was observed in 10 patients (19%), two of whom showed high intensity on T2WI. High intensity on T2WI was observed in 3 patients (5.8%). LV mass index and LV mass/end-diastolic volume tended to be higher in the LGE-positive group than in the LGE-negative group (P = 0.078 and 0.093, respectively). Salivary gland focus score (FS) ≥ 3 was independently associated with LGE-positive in the multivariable analysis (OR 11.21, 95% CI 1.18-106.80). CONCLUSION: Subclinical myocardial fibrosis, as detected by cMRI, was frequent in patients with pSS without cardiac symptoms. Abnormal cMRI findings were associated with salivary gland FS ≥ 3.

Heart Rate-corrected QT Interval Duration in Rheumatoid Arthritis and Its Reduction with Treatment with the Interleukin 6 Inhibitor Tocilizumab.

OBJECTIVE: Individuals with rheumatoid arthritis (RA) are at a heightened risk of sudden cardiac death, an outcome increased in those with prolongation of the corrected electrocardiographic QT interval (QTc). We compared QTc between patients with RA and demographically matched controls and studied the change in QTc after treatment with the interleukin 6 inhibitor tocilizumab (TCZ). METHODS: Standard 12-lead electrocardiograms were obtained and QTc was measured in patients with RA at baseline and after 24 weeks of TCZ treatment, then compared with non-RA controls who were frequency-matched on age and sex. Indicators of the baseline QTc and predictors of change in QTc were studied using multivariable linear regression. RESULTS: A total of 94 RA and 42 non-RA controls were studied. The average baseline QTc was 10 ms longer in the RA group vs controls (422 vs 412 ms, respectively; p < 0.001) and decreased to an average of 406 ms with treatment (p < 0.001). Baseline QTc was significantly and independently higher among those with anticyclic citrullinated peptide antibodies seropositivity, higher swollen joint counts, and higher levels of C-reactive protein (CRP) and matrix metalloproteinase 3. Each log unit decrease in CRP with treatment was associated with an average reduction in QTc of 2.9 ms (p = 0.002) after adjusting for age and baseline QTc. Clinical response measures were not associated with the change in QTc. CONCLUSION: The marked normalization of QTc observed with TCZ treatment, and its close parallel with CRP reduction, support the premise that systemic inflammation contributes to cardiac repolarization abnormalities in RA that may be amenable to treatment.

Remarkably Intense Emission from Ruthenium(II) Complexes with Multiple Borane Centers.

The electrochemical, spectroscopic, and phophysical properties of a series of Ru(II) complexes having a triarylborane-appended 2,2'-bipyridine (bpy) ligand(s) (RuBbpys: [Ru(Bbpy)n(bpy)(3-n)](2+) (B1n) and [Ru(B2bpy)n(bpy)(3-n)](2+) (B2n), B = (dimesityl)boryldurylethynyl group(s) at the 4- or 4,4'-position(s) in bpy, n = 1-3) are described. In the excited states of the complexes, the intramolecular charge transfer transitions between the π-orbital of the aryl group and the vacant p-orbital on the boron atom (π(aryl)-p(B) CT) synergistically interact with the metal-to-ligand charge transfer (MLCT) transitions. The molar absorption coefficient of the MLCT band (ε(MLCT)) of the complex increased with increasing n, and B23 showed extremely intense absorption with ε(MLCT) = 5.6 × 10(4) M(-1) cm(-1) at 488 nm. Furthermore, B23 showed the highest emission quantum yield (0.43) among those of the polypyridine Ru(II) complexes hitherto reported. As one of the interesting results, we report that the radiative rate constant of B2n shows the correlation with ε(MLCT). The effects of the synergistic MLCT/π(aryl)-p(B) CT interactions on the spectroscopic and photophysical characteristics of RuBbpys are discussed in detail.

[Diagnostic value of brain biopsy in intravascular large B-cell lymphoma mimicking progressive multifocal leukoencephalopathy: case report].

We report a 68-years-old woman with systemic sclerosis and interstitial pneumonia (IP). She had developed subacute progressively encephalopathy and dementia while treated with oral cyclophosphamide and prednisolone. She admitted to our hospital because of syncope. Laboratory tests indicated slight elevated cerebrospinal fluid protein, and levels of serum C-reactive protein (CRP), levels of soluble IL-2 receptor was normal. But, magnetic resonance imaging (MRI) of the brain showed multiple infarct-like lesions mainly in the white matter, which mimics progressive multiple leukoencephalopathy (PML). Twenty days after admission, the retested MRI of the brain disclosed initial lesions progressively enlarged and numbers of the lesions were increased. The polymerase chain reaction (PCR) for JC virus of cerebrospinal fluid was negative. To make diagnosis, brain biopsy was performed. Microscopic examination revealed that small vessels were filled with lymphoma cells (CD20+, CD79+, CD3-), and intravascular lymphoma (IVL) was diagnosed. She treated with regimens of R-CHOP. After chemotherapy her consciousness and dementia were gradually improved. IVL of central nerve system (CNS) is a rare disease, and its common symptoms are ischemia, infarction and dementia. Diagnosis of IVL of CNS is difficult when the lesion mimics PML, and patient with similar laboratory examinations and radiographic findings of PML should undergo brain biopsy detected malignant cell in small vessels, which is a value of diagnosis.

Epstein-Barr virus induces erosive arthritis in humanized mice.

Epstein-Barr virus (EBV) has been implicated in the pathogenesis of rheumatoid arthritis (RA) on the basis of indirect evidence, such as its presence in affected joint tissues, antigenic cross reactions between EBV and human proteins, and elevated humoral and cellular anti-EBV immune responses in patients. Here we report development of erosive arthritis closely resembling RA in humanized mice inoculated with EBV. Human immune system components were reconstituted in mice of the NOD/Shi-scid/IL-2Rγ(null) (NOG) strain by transplantation with CD34(+) hematopoietic stem cells isolated from cord blood. These humanized mice were then inoculated with EBV and examined pathologically for the signs of arthritis. Erosive arthritis accompanied by synovial membrane proliferation, pannus formation, and bone marrow edema developed in fifteen of twenty-three NOG mice transplanted with human HSC and inoculated with EBV, but not in the nine NOG mice that were transplanted with HSC but not inoculated with EBV. This is the first report of an animal model of EBV-induced arthritis and strongly suggest a causative role of the virus in RA.

[Two cases of isolated ACTH deficiency suspected as depression with severe appetite loss].

Diagnosing isolated ACTH deficiency can be a challenging task for a clinician due to its non-specific symptoms, such as a decreased appetite, general fatigue, and psychological dysfunction. This report is on two patients with isolated ACTH deficiency who presented with extreme appetite loss and were referred for psychiatric evaluation with a suspected diagnosis of depression. CASE I: A business executive in his late sixties showed severe appetite loss and vomiting in May of the year X. His business had started to experience difficulty two months earlier. A medical workup of the digestive system and a brain MRI revealed no abnormality. Subsequently, the patient was referred for a psychiatric examination with suspected depression in August. Psychiatric pharmacotherapy improved his appetite only temporarily, and he was admitted as a psychiatric inpatient. A more thorough evaluation led to a diagnosis of isolated ACTH deficiency on the basis of abnormally low levels of ACTH and cortisol. The patient's symptoms improved with hydrocortisone supplementation. CASE II: A factory worker in his late fifties started to experience appetite loss, nausea/ vomiting, and decreased energy in May of the year Y, without any apparent cause. Medical evaluations by a family physician, a digestive system specialist, and a neurologist, including a brain CT, were unremarkable. Depression was suspected and the patient was referred to the authors' psychiatric clinic in July of the same year. Upon examination, the patient presented with depressive symptoms such as a depressed mood, decreased energy, middle insomnia, and loss of interest. Blood tests and a hormonal workup revealed abnormally low ACTH and cortisol levels. The patient was admitted as an inpatient of the endocrinology department, and a diagnosis of isolated ACTH deficiency was made. Hydrocortisone supplementation improved his symptoms. In both cases, anti-pituitary antibody was negative and there were no findings of an empty sella or swelling of the pituitary gland. Therefore, isolated ACTH deficiency was a more likely diagnosis than lymphocytic adenohypophysitis. It is important to diagnose this condition as early as possible since it is treatable with hydrocortisone supplementation with a favorable prognosis. Screening for ACTH and cortisol levels should be considered when symptoms of suspected depression include severe general fatigue and appetite loss with vomiting.

Epstein-Barr-Virus-Infected CD15 (Lewis X)-Positive Hodgkin-Lymphoma-Like B Cells in Patients with Rheumatoid Arthritis.

Patients with rheumatoid arthritis (RA), especially those who are treated with methotrexate (MTX), might have an increased risk of Hodgkin lymphoma (HL), a malignancy that is associated with Epstein-Barr virus (EBV). Here we describe a monoclonal EBV-infected B-lymphoblastoid cell line (LCL) called TKS-1 that was established from cells that spontaneously converted from an MTX-treated RA patient. TKS-1 has properties similar to HL cells and it is distinctly different from control LCLs established from normal individuals. TKS-1 cells express the HL -associated surface markers CD15 and CD30 (Takei et al. 1989). Like Hodgkin Reed-Sternberg (H-RS) cells of EBV-positive HL, TKS-1 cells express EBNA1 mRNA transcribed from the Qp promoter of the virus, whereas control LCLs use the Cp or Wp promoter to transcribe mRNA. TKS-1 cells can proliferate in an anchorage-independent manner and possess a cloning efficiency comparable to that of the Burkitt lymphoma (BL) line Raji. In addition, two EBV-positive LCLs established by cocultivated CD34+ cells isolated from the bone marrow of patients with RA and peripheral blood B lymphocytes from a healthy EBV-seronegative individual also expressed CD15. These results indicate that EBV-infected B-lymphoblastoid cells from patients with RA tend to acquire properties similar to HL cells.