Mayumi Koga

CD14+CD16+ monocyte subpopulation in Kawasaki disease

Kawasaki disease (KD) is an acute febrile illness caused by vasculitis, occurring in early childhood. We have demonstrated that the activation of monocytes/macrophages plays a central role during acute KD. Recently, it has been reported that the CD14+CD16+ monocyte subpopulation plays a more important role in inflammation. In this study, we investigated the peripheral blood CD14+CD16+ monocyte subpopulation by flow cytometry, and serum levels of IL‐10 and IL‐12 using a sandwich ELISA in 28 KD patients. We also investigated this subpopulation in patients with bacterial infections, mononucleosis and anaphylactoid purpura, since the cause of KD remains unknown. We observed an increase in the number of CD14+CD16+ monocytes with acute KD, which was a positive correlation with C‐reactive protein levels, and we observed only the patients with severe bacterial infections had increased this subpopulation during the acute stage among control diseases. In addition, we found that the serum levels of IL‐10, but not IL‐12, were higher during acute KD. These data suggest that increased peripheral blood CD14+CD16+ monocytes are part of the regulatory system of monocyte function during acute KD.

Increase of cord blood cytokine-producing T cells in intrauterine infection

Abstract Background : Although infection is a frequent and important cause of morbidity and mortality in the neonatal period, evaluation of the immune system in cases of intrauterine infection is not easy. The subsets of T helper (Th) 1, which produce mainly interferon gamma (IFN‐γ), and Th2, which produce interleukin (IL) ‐4, have been implicated in the regulation of many immune responses. In this study, we investigated Th1 and Th2 subsets in the cord blood (CB) to evaluate the role of CB T cells in the intrauterine infections.

Cerebral Hypoperfusion During Acute Kawasaki Disease

BACKGROUND AND PURPOSE Kawasaki disease is a febrile disease of children notable for systemic vasculitis. There have been many previous reports of various complications, including disorders of the central nervous system. We evaluated cerebral perfusion during the acute stage in patients with Kawasaki disease. METHODS Single-photon emission-computed tomography (SPECT) with 99mTc-hexamethylpropyleneamine oxime was performed in 21 children with acute stage Kawasaki disease. Follow-up SPECT and MRI were performed about 1 month after the first SPECT in patients who exhibited abnormal SPECT findings during the acute stage. RESULTS In 6 of 21 children SPECT imaging demonstrated localized cerebral hypoperfusion without abnormal neurological findings or clinical symptoms, and the follow-up SPECT and MRI approximately 1 month after the first SPECT revealed no abnormalities. CONCLUSIONS Some patients with Kawasaki disease have transient localized cerebral hypoperfusion at the acute stage.

Decreased interferon-gamma (IFN-γ)-producing T cells in patients with acute Kawasaki disease

Kawasaki disease (KD) is an acute febrile illness of early childhood, in which the activation of monocytes/macrophages plays a central role in the development of vasculitis during the acute stage of disease. In this study we investigated peripheral blood T cells of 10 patients with KD, focusing on the Th1 and Th2 imbalance, using intracellular cytokine staining and analysis of the cytokine‐producing T cells by flow cytometry. We observed a decrease in the numbers of IFN‐γ‐producing, but not IL‐4‐producing, CD3+ T cells, during the acute stage. Our results suggest that there is an imbalance of Th1 and Th2 subsets during the acute stage of KD.

Activation of peripheral blood monocytes and macrophages in Kawasaki disease : Ultrastructural and immunocytochemical investigation

Monocytes/macrophages are considered to play an important role in the pathogenesis of Kawasaki disease (KD). However, the morphological and Immunocytochemical features of the cells in acute KD have not been investigated. The ultrastructural and Immunocytochemical characteristics of peripheral blood CD14+ monocytes/macrophages sorted by a magnetic cell sorter (MACS) during the course of KD were, therefore, studied to evaluate their role in the disease pathogenesis. Electron microscopy showed that CD14+ monocytes/macrophages from patients with acute KD had nuclei with complex shapes, apparent nucleoli and abundant intracytoplasmlc granules, some of which were positive for acid phosphatase. The quantity of intracy‐toplasmic granules was correlated with disease severity, in terms of the duration of fever, maximum level of C‐reactive protein and the presence of coronary artery lesions (CAL), suggesting that the monocytes/macrophages were activated and showed increased phagocytosis. Immunocytochemical staining of smears made from cell suspensions of sorted CD14+ monocytes/macrophages was carried out using a monoclonal antibody against tumor necrosis factor (TNF)‐α. The cytoplasm of monocytes/macrophages from patients with acute KD was strongly positive in comparison to that of cells from control subjects, suggesting that intracytoplasmic granules secrete TNF‐α.

Amyloid Fibril Formation in the Rough Endoplasmic Reticulum of Plasma Cells from a Patient with Localized Aλ Amyloidosis

Evidence for amyloid fibril formation in rough endoplasmic reticulum (RER) of plasma cells from the duodenum of a 62-year-old man with localized A lambda amyloidosis is described. The inclusions in RER of plasma cells were composed of tightly packed, regular arrays of fibrils cut in both longitudinal and cross-sections. The fibrils within the inclusions, measuring 10 nm in width, were oriented parallel to the long axis of the inclusions. By immunoelectron microscopy with an antihuman A lambda antiserum, gold particles labeled the fibrils located both in the RER of plasma cells and in the extracellular space. In addition, electron-dense material in the dilated RER was occasionally labeled. These findings suggest that at least some amyloid fibrils are unequivocally created in the RER of plasma cells.

Maturation of macrophages from peripheral blood monocytes in Kawasaki disease: Immunocytochemical and immunoelectron microscopic study

Kawasaki disease (KD) is regarded as a cytokine‐associated disorder. Despite intensive investigation into the etiology of KD, this remains unclear, although monocytes and macrophages are thought to play an important role. We examined peripheral blood monocytes using a monoclonal antibody, PM‐2K, which recognizes mature macrophages but not monocytes. This study was conducted in 12 patients with KD, three patients with sepsis and 12 control subjects. Approximately 8% of whole peripheral blood monocytes from patients with acute KD were observed to be PM‐2K positive. Approximately 15–20% of peripheral blood CD14+ monocytes from these patients were positive for PM‐2K antibody (as determined by immunoelectron microscopy). PM‐2K‐positive monocytes had significantly fewer numbers of intracytoplasmic peroxidase‐positive granules than monocytes from control subjects. In contrast, PM‐2K‐negative monocytes from patients with acute KD had a significantly greater number of peroxidase‐positive granules in the cytoplasm than in those from controls. Monocytes from patients with sepsis displayed PM‐2K immunocytochemical staining, similar to that in monocytes from patients with KD. These results suggest that during the acute stage of KD, monocytes partly differentiate into macrophages in the peripheral circulation.

An autopsy case of Farber's lipogranulomatosis in a Japanese boy with gastrointestinal involvement.

A boy with Farbers lipogranulomatosis is reported. Excessive ceramide was revealed by thin‐layer chromatography of the extracts from the liver. Acid ceramidase activity of the liver was 31.5% of control with exogenous substrate and 33.3% without exogenous substrate. The histological appearance showed granulomatous lesions, composed of spindle or oval‐shaped storage cells and proliferation of the connective tissues, in the subcutaneous tissue of the lower lip, periarticular regions and the pericardium. Histo‐chemically the storage cells were revealed to contain lipid and polysaccharide. The foreign body granuloma formed by the surgical suture in the liver was surrounded by a large number of foamy cells. In gastrointestinal mucosa widespread erosion, disappearance of glands and abundant collagen fibers were noted. On electron microscopy, the spindle or oval shaped cells in the subcutis of the lip had intracytoplasmic inclusions containing granular or fibrillar materials and a smaller number of curvilinear structures, so called “Farber bodies”. Our case was a typical clinical and histopathological presentation of Farbers lipogranulomatosis. However, ceramidase activity was higher than in previous descriptions, and severe gastrointestinal lesions and the appearance of a large number of foamy cells around the foreign body granuloma have not been described previously.

CD8+ T-lymphocytes infiltrate the myocardium in fulminant herpes virus myocarditis.

We report two cases of fulminant viral myocarditis in previously healthy children. They were caused by herpes simplex virus (HSV)-I (in a boy aged 3 years) and Epstein-Barr virus (EBV) (in a boy aged 12 months). We obtained the diagnosis of HSV-l myocarditis by immunohistochemistry and the diagnosis of EBV myocarditis by in situ hybridization. Histologic examination of heart tissue from the two boys revealed mononuclear cell infiltration of the myocardium. Immunohistochemical staining identified these cells as CD8+ T-lymphocyles. CD8+ T-lymphocytes induced by herpes virus infections may play an important role in the damage to heart muscle fibers seen in fulminant myocarditis in previously healthy children. To our knowledge, this is the first report of HSV-l or EBV myocarditis (at least in children) in which viral infection has been demonstrated in the myocardium.

A case of Farber disease.

We report a case of Farber disease (Farber lipogranulomatosis). The main features were a shrill voice, joint swelling, subcutaneous nodules and retarded psychomotor development. Cytological investigation revealed intracytoplasmic inclusion bodies characteristic of Farber disease. Lipid analysis of liver tissue indicated an accumulation of ceramide containing non‐hydroxy fatty acids. It was found that the acid ceramidase activity in the liver was reduced to 31% of the control value. In this patient there were also persistent diarrhea, cholelithiasis, transient proteinuria and increased urinary total sialic acids. These features have not been noted in previously reported cases.