Rheumatoid synovial endothelial cells produce macrophage colony-stimulating factor leading to osteoclastogenesis in rheumatoid arthritis.

OBJECTIVES: Periarticular osteoporosis and joint destruction are major complications in rheumatoid arthritis (RA), caused by osteoclast-mediated bone resorption. However, the mechanisms of monocyte/osteoclast maturation and role of RA endothelial cells (RAECs) in the control of osteoclastogenesis remain unclear. The present study was designed to determine the most important factors that influence monocyte accumulation and osteoclast formation among the many factors produced by RAEC. METHODS: We analysed the expression profiles of various genes in human endothelial cells from various organs (RA synovium, umbilical vein, skin, liver sinusoid, renal glomerulus and brain) using oligonucleotide microarrays. Specifically, up-regulated gene in RAECs was assessed by real-time quantitative polymerase chain reaction, enzyme-linked immunosorbent assay and immunostaining of RA synovia. Migration of monocytes was assessed by the chemotactic chamber EZ-TAXIScan. Tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cell (MNC) formation was observed by microscopy. RESULTS: Among many epithelial-expressed factors, macrophage colony-stimulating factor (M-CSF) gene was abundantly expressed specifically in RAECs. Genes of fibroblast growth factor-2, interleukin-6 and osteoprotegerin were also overexpressed in RAECs. Migration of monocytes and osteoclast formation in co-cultures promoted by culture supernatants of RAECs were inhibited by M-CSF neutralizing antibody. CONCLUSIONS: M-CSF produced by RAECs is involved in osteoclastogenesis from monocytes, migration and TRAP-positive MNC formation.

A comparison of gene expression in murine cardiac allografts and isografts by means DNA microarray analysis.

BACKGROUND: Acute rejection of allografts remains a significant problem in clinical transplantation, and the fundamental mechanism underlying this rejection are as yet only poorly elucidated. Recently, DNA microarrays have come into use for the study of gene expression profiles, and we have taken advantage of this new technology to investigate acute rejection. We compared mRNA profiles in murine cardiac allografts with isografts using DNA microarrays with probe sets corresponding to more than 11,000 mice genes. METHODS: We screened for gene expression changes in murine cardiac allografts between fully incompatible mice strains (BALB/c H2d to C3H/He H2k) using a DNA microarray. The heart was heterotopically transplanted. Allografts (BALB/c to C3H/He) were removed on days 1, 3, and 5. As a control, isografts (C3H/He to C3H/He) harvested on days 1, 3, and 5 and native hearts of both strain mice (C3H/He and BALB/c) were obtained. RESULTS: On day 5, interferon-gamma (IFN-gamma) and many IFN-gamma-inducible genes were profoundly induced in the allograft relative to isograft. Monokine induced by IFN-gamma was most profoundly induced followed by inducibly expressed GTPase and Lmp-2. IFN-gamma was also profoundly induced. The induction was detectable from day 3. In contrast, genes regulated by other cytokines exhibited only modest changes. CONCLUSION: IFN-gamma-inducible genes are specifically up-regulated in murine cardiac allografts, suggesting that signaling mediated by IFN-gamma may play an important role in the late phase of acute rejection in vivo.

In vitro model of atherosclerosis using coculture of arterial wall cells and macrophage.

In order to determine the precise mechanism of the interactions between different types of cells, which are common phenomena in tissues and organs, the importance of coculture techniques are becoming increasingly important. In the area of cardiology, artificial arteries have been developed, based on the understanding of physiological communication of the arterial smooth muscle cells (SMC), endothelial cells (EC), and the extracellular matrix (ECM). In the study of atherosclerosis, the modification of low-density lipoprotein (LDL), which result in the recruitment and accumulation of white blood cells, especially, monocytes/macrophages, and foam cell formation, are hypothesized. Although there are well known animal models, an in vitro model of atherogenesis with a precisely known atherogenesis mechanism has not yet been developed. In this paper, an arterial wall reconstruction model using rabbit primary cultivated aortic SMCs and ECs, was shown. In addition, human peripheral monocytes were used and the transmigration of monocytes was observed by scanning electron and laser confocal microscopy. Monocyte differentiation into macrophages was shown by immunohistochemistry and comprehensive gene expression analysis. With the modified form of LDL, the macrophages were observed to accumulate lipids with a foamy appearance and differentiate into the foam cells in the ECM between the ECs and SMCs in the area of our coculture model.

Genomic structure and mapping of human orphan receptor LXR alpha: upregulation of LXRa mRNA during monocyte to macrophage differentiation.

In order to identify changes in the gene expression profile during human monocyte/macrophage differentiation in the presence of GM-CSF, the expression level of various mRNA was studied using DNA microarray technology. We found LXR alpha (LXRa) to be the most highly induced transcriptional regulator during macrophage differentiation. The LXRa mRNA level was induced 40 fold which ranked it as the 10th highest among the approximately 5,600 genes studied. Although only restricted hepatic expression of LXRa mRNA had been reported, the macrophage expressed the highest level of LXRa among the nine human tissues and cultured cells studied. To further investigate transcriptional control, we have characterized the genomic structure of the human LXRa gene and determined the structure of its promoter region. The human LXRa gene consists of eleven exons, and analysis of the promoter region indicated the presence of conserved binding sites for myeloid zinc finger protein 1, which may be related to the extrahepatic expression of LXRa. LXRa is known to be activated by oxysterols, and the induced expression of the gene may be related to the foam cell formation in atherosclerotic lesions.

The gene expression profile of human umbilical vein endothelial cells stimulated by tumor necrosis factor alpha using DNA microarray analysis.

Stimulation of vascular endothelial cells by tumor necrosis factor alpha (TNFalpha) plays a critical role in the pathogenesis of inflammation and vascular diseases. Changes in the gene expression profile in cultured human umbilical vein endothelial cells (HUVEC) treated with TNFalpha was analyzed with high-density oligonucleotide arrays comprised of 35,000 genes. TNFalpha stimulation profoundly induced genes involved in signal transduction, leukocyte adhesion and chemoattraction. ICAM-1 mRNA (fold change 111.9) was most profoundly induced followed by TNFalpha receptor-associated factor 1 (TRAF1) (95.5), Bcl3 (71.8), IL8 (65.4), fractalkaine (62.4), E-selectin (48.0), lymphotoxin beta (41.3) and VCAM-1 (31.7). In addition to these previously known genes, 18 poorly characterized or novel genes known as ESTs profoundly induced by TNFalpha. Initial sequencing analysis identified three of these the genes for squalene epoxydase, chromodomain helicase DNA binding protein 4, and CLP respectively. Further analysis of these genes will provide important information about TNFalpha signaling and function in vascular endothelial cells.

[Scavenger receptor family].

After the proposal of scavenger pathway hypothesis, a family of genes have been discovered. Here we show the precise properties of the first cloned scavenger receptor class A type I and II. Then the profiles of other members of scavenger receptors including lectin receptors are shown briefly.

A 20-year case study of a kidney transplant recipient with chronic active hepatitis C: clinical course and successful treatment for late acute rejection induced by interferon therapy.

BACKGROUND: The influence of hepatitis C virus (HCV) infection has been discussed in kidney transplantation. Our case study focused on four points: the clinical course of an HCV-infected recipient; the pathogenesis of hepatic disorders in such a patient; interferon (IFN)-alpha therapy; and the risk of IFN-alpha therapy. METHOD: A patient was suspected of acquiring HCV via transfusion at kidney transplant. He was examined several times serologically, virologically, endoscopically, and pathologically during a 20-year follow-up. RESULTS: Abnormal biochemical markers were found within a month after transplantation but recovery occurred without any treatment. Within 3 years postoperatively, hepatic disorder developed including peliosis hepatis, nodular regenerative hyperplasia, and cholestasis. These pathological conditions were ascribed to immunosuppressants: cyclophosphamide and azathioprine. Abnormal chemical markers decreased to normal values for 4 consecutive years with the substitution of cyclophosphamide and azathioprine for mizoribine. During the subsequent 13 years, the patient developed chronic hepatitis with clinical and morphological features of hepatitis C infection. Anti-HCV antibody was positive from the second post-transplant year and HCV genome was detected in the 17th year. IFN-alpha therapy was initiated in the 17th year and resulted in normal transaminase activities with no effect on viremia. However, acute cellular rejection developed. The rejection was steroid resistant but responsive to OKT3. CONCLUSION: HCV might remain latent for approximately 7 years even in kidney recipients unless toxic hepatitis occurs. Hepatotoxic drugs may cause a wide spectrum of liver diseases in HCV carriers as a result of the overload of immunosuppressants on hepatocytes. IFN-alpha could induce acute cellular rejection even in the 17th year. Such acute rejection can be reversible with OKT3.

Malignant lymphoma originating in the jejunum of a long-term follow-up case of protein-losing enteropathy.

A 50-year-old female patient, who had been followed for 15 years for protein-losing enteropathy, was hospitalized due to epigastric pain. Examination on admission revealed that the patient was in the sub-ileus state. On the 26th day after admission, she complained of severe abdominal pain and shortly after she went into shock. The emergency laparotomy documented intestinal perforation and a tumor. The perforated site was right at the middle of tumor. The histological and histochemical studies identified the tumor as malignant lymphoma of B lymphocyte lineage. As far as we know, this is the third case of malignant lymphoma occurring in the jejunum in a patient with protein-losing enteropathy in Japan. The possible relationship between lymphomas and protein-losing enteropathy is discussed.

Laparoscopic study of peliosis hepatis and nodular transformation of the liver before and after renal transplantation: natural history and aetiology in follow-up cases.

Although peliosis hepatis and nodular transformation of the liver can occur after renal transplantation, their prevalence has not been well defined. To investigate the incidence of these complications, 137 laparoscopies were studied, 52 in 50 cases before and 85 in 66 cases after renal transplantation. To elucidate the aetiology and natural history of these diseases, cases were followed up by repeated laparoscopies. Peliosis was observed after transplantation (before: n = 1, after: n = 15 [22%], p < 0.005). Nodular transformation was seen only after transplantation (n = 5 [7%]), and was accompanied by peliosis (n = 4, p < 0.01). On observation before and after transplantation in the same cases, these diseases appeared after transplantation (peliosis: n = 9, p < 0.005; nodular transformation: n = 2). In follow-up cases, these diseases were confirmed after the discontinuation of or the controlled administration of immunosuppressants. The aetiology of the micronodular transformation which appeared following peliosis in a case treated without cyclosporin was shown to be azathioprine. However, the macronodular transformation observed in two cases treated with both azathioprine and cyclosporin seemed to be due to cyclosporin. This suggests that cases of peliosis hepatis and nodular transformation which appear after renal transplantation are associated with immunosuppressants, and that cyclosporin treatment may also affect the morphogenesis of nodular transformation.

Histiocytic neoplasias: immunohistochemical evaluation of their frequencies among malignant lymphoma and related conditions in Japan.

Through histologic review of 1,766 cases with malignant lymphoma and related conditions, 35 cases (2%) were selected as probable histiocytic neoplasias. Proliferating cells in these cases had voluminous, granulated cytoplasm, and round to irregularly shaped nuclei often with bi- or multinucleated forms showing monomorphous or polymorphous proliferation accompanying small lymphocytes, plasma cells, and, less frequently, eosinophils. Cases showing proliferation of convoluted cells with numerous benign-appearing histiocytes or large cells with clear cytoplasm were excluded under a diagnosis of T-cell lymphoma. To evaluate the immunologic character of proliferating cells, immunohistochemistry using antibodies Mx-Pan B, MB-1, MT-1, UCHL-1, lysozyme, alpha 1-antitrypsin, alpha 1-antichymotrypsin, S-100 alpha, S-100 beta, Leu M1, epithelial membrane antigen, and Ki-1 were carried out in 23 cases. Naphthol-ASD-chloracetate reaction and toluidine blue stain were also performed. These procedures revealed that 12 cases (52%) were B-cell type, three cases (13%) T-cell type, six cases (26%) true histiocytic type, and two cases null type. Therefore, the frequency of cases with true histiocytic neoplasias among cases with malignant lymphoma and related conditions in Japan may be 0.5%.

[A review of childhood cases of malignant lymphoma in Osaka, Japan].

Fifty-one cases of malignant lymphomas in patients under 20 years of age have been reviewed in Osaka, Japan. The breakdown of these cases revealed 6 cases (11.8%) of Hodgkin's disease (HD) and 45 cases (88.2%) of a non-Hodgkin's lymphoma (NHL). Both the HD and NHL cases were determined by using the Rye classification, as well as the Rappaport, Kiel, and LSG classifications, respectively. The results have shown that (1) the incidence of HD in childhood is the same as that seen in the adult in Japan; (2) that a NHL of the nodular type is rare in Japan as it is in Western countries; (3) that any significant differences were not present in the distribution of each histologic subtype in the cases of a NHL among Japan and Western countries, and that the lymphoblastic type was the most common. From this study it is concluded that geographical differences were not a factor in comparing cases of childhood malignant lymphomas in Japan and Western countries.

[A case of transitional cell carcinoma of the bladder with heterotopic bone formation].

A 85-year-old woman consulted our clinic due to asymptomatic macrohematuria on January 6, 1987. In the cystoscopic examination, solitary and pedunculated bladder tumor was revealed. This tumor was located on the retrotrigonal region near the right ureteral orifice. On January 20, transurethral resection of bladder tumor was planned but the base of the tumor was stony hard, so complete resection was not performed. On February 10, transurethral resection of bladder was performed repeatedly. At that time, the cystoscopic finding showed that the tumor size had increased and transurethral bladder ultrasonography showed invasion into the deep muscular layer. On February 17, total cystectomy and ileal conduit was done. Histological examination revealed poorly differentiated TCC with osteoid, bone and cartilage. This patient was discharged in good condition on March 27. Heterotopic bone formation in the bladder tumor is rare. Ten cases were collected from the literature. We report a case of heterotopic bone formation and discuss the mechanism of the etiology.

Choriocarcinoma in infant and mother.

A 2-month-old female baby was noticed to have liver tumor. A hemangioma of the right lobe was suspected from the findings by celiac angiography. Histologic findings of the surgically resected material revealed choriocarcinoma of the liver. At autopsy, multiple metastatic nodules were found in the lungs, but remnant liver, ovaries, uterus, mediastinum, and sacrococcygeal region were free of tumor. The ovary had several thecalutein cysts, and the endometrium of the uterus showed pseudodecidual change of the stroma. The mother died two months later. Although histologic materials were not available, the clinical findings including a high value of serum HCG seemed to show that she had been affected by choriocarcinoma. The most probable origin of the choriocarcinoma in the infant from the mother is discussed.