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61.
Interleukin-1, a peptide produced by monocytes, histiocytes, and interdigitating reticulum cells, plays an important role in the regulation of immune function. In this styde, we examined the production of interleukin-1 in 115 patients with a variety of human lymphomas by using a rabbit anti-interleukin-1 antibody and the immunoperoxidase technique. Interleukin-1 was detected in Reed-Sternberg cells from 20 patients with Hodgkin's disease as well as in neoplastic cells from 9 patients with true histiocytic lymphoma or malignant histiocytosis. In the other 86 cases, which included T- and B-cell lymphomas, no interleukin-1 could be detected. This result indicates a close relationship between Hodgkin's disease and true histiocytic malignancies and provides additional evidence to support our hypothesis that Reed-Sternberg cells are related to interdigitating reticulum cells.  相似文献   
62.
H W Hsu  P Schwartzberg  S P Goff 《Virology》1985,142(1):211-214
A series of point mutations in the P30 domain of the Moloney murine leukemia virus gag gene was generated by bisulfite treatment of heteroduplex DNAs containing a single-stranded region in the gag gene. One virus bearing such a mutation exhibited a coordinate defect in gag and pol function, and was similar to previously described deletion mutants with alterations in this gene. One mutant virus displayed a different phenotype: it could assemble virion particles and provide pol function, but the particles were defective in the early stages of infection. The continued concordance of the mutants' failure or ability to both assemble virions and provide pol lends further support to the proposal that similar parts of the gag gene are required for these two processes.  相似文献   
63.
Hodgkin's mononuclear cells, Reed-Sternberg (H-RS) cells, and U-937 and SU-DHL-1 histocytic cell lines were induced to differentiate by phorbol ester in cultures. The phenotypes of cells were determined by a panel of antibodies specific for monocytes, histiocytes, and interdigitating reticulum cells. Before induction, SU-DHL-1 cells and H-RS cells expressed similar markers, such as HeFi-1, 2H9, 1A2, and 1E9. In addition, SU-DHL-1 cells were also stained by Tac and Leu M5. Other monocyte markers, including OK M1, Co Mo2, BRL Mo1, BRL Mo2, and Leu M3 were consistently negative in both types of cells. After induction, SU-DHL-1 cells conserved the same phenotype, but H-RS cells became negative for HeFi-1, 1A2, and 2H9. The U-937 cells expressed Leu M1 and Co Mo2 and became positive for Leu M5, OK M1, Co Mo2, BRL Mo2, 2H9, and 1E9 after phorbol ester induction. The U-937 cells did not express HeFi-1 or 1A2. The marker expression of H-RS cells, SU-DHL-1 cells, and U-937 cells were compared with those of histiocytes or interdigitating reticulum cells in lymphoid tissues and with neoplastic cells in true histiocytic lymphoma and malignant histiocytosis. It is concluded that SU-DHL-1, U-937, and H-RS cells are derived from or most closely related to fixed histiocytes, free histiocytes, and interdigitating reticulum cells, respectively. Our study further confirms the diagnosis of SU-DHL-1 as true histiocytic lymphoma but reveals that U-937 is a case of malignant histiocytosis rather than the previously diagnosed histiocytic lymphoma. The phenotypes and induction properties of SU-DHL-1 cells are quite different from those of U-937 cells, which suggests that true histiocytic lymphoma and malignant histiocytosis are two distinct disease entities.  相似文献   
64.
Wear and wear debris of ultrahigh molecular weight polyethylene (UHMWPE) in joint replacements have been recognized as one of the major contributors to the failure of orthopedic implants. The detailed wear mechanism of polyethylene under biomechanic motions is not well understood. In simulation wear bench tests, it was found that unidirectional sliding produces the least amount of wear, reciprocating motion increases wear significantly, and cross-shear motion (similar to hip and knee joint motion in the human body) produces the highest amount of wear. Conventional wear theories are inadequate to explain this observation. This study utilizes resonant absorption of linearly polarized soft X-rays at a synchrotron radiation beam line to measure the molecular orientation of a UHMWPE surface layer subjected to different wear motions. Carbon-K-edge partial-electron-yield X-ray absorption measurements were done on the worn UHMWPE samples. X-ray absorption measurements show conclusively that the molecular chains of UHMWPE align preferentially parallel to the direction of sliding. Examination under various wear motions showed that unidirectional shear produced the maximum chain orientation, whereas cross-shear wear motions produced the least amount of orientation. When polymeric chains align, the surface layer tends to be more brittle and hard, thus resisting wear. When they do not align, loose chains may be subjected to both Mode I and Mode II fracture, hence increasing the wear rate. This molecular alignment observation may offer an explanation of why different wear motions have different wear characteristics.  相似文献   
65.
Hodgkin's disease (HD) is a neoplastic disease that is characterized by unbalanced and/or unregulated cytokine production. Information accumulated in our own and other laboratories indicates that the cytokines interleukin-1 (IL-1), IL-5, IL-9, tumor necrosis factor-alpha (TNF-alpha), granulocyte colony-stimulating factor (G-CSF), macrophage CSF (M-CSF), and transforming growth factor-beta (TGF-beta) are secreted by Hodgkin's and Reed-Sternberg (H-RS) cells. These and perhaps additional cytokines are likely to be responsible for the unique histopathologic and clinical alterations seen in patients with HD. In this study, we confirmed that IL-6 is produced by cultured H-RS cells as well as by H-RS cells in tissues. By using an enzyme-linked immunosorbent assay, we found that approximately 2 to 10 ng/ml of IL-6 was secreted by cultured H-RS cells (10(6) cells/ml). In tissues, we were able to immunolocalize IL-6 in the cytoplasm in 10 to 30% of H-RS cells by using rabbit polyclonal and mouse monoclonal anti-IL-6 antibodies. There was no correlation among the IL-6 staining intensity, number of H-RS cells stained, and the degree of plasma cell infiltration. However, in 3 of 17 cases studied, a large number (60%) of H-RS cells were positive for IL-6, and in these patients, abundant plasma cells were present. In one patient, the involved lymph node also showed histologic features similar to those of Castleman's disease. In this patient, we noted abundant IL-6 expression not only in H-RS cells, but also in most reactive histiocytes. The cultured H-RS cells did not express functional receptors for IL-6, and exogenously added IL-6 did not induce proliferation of these cells. We also conducted studies with specific anti-IL-4 antibodies, which did not show IL-4 production by H-RS cells in both cultures and tissues. In tissues, only rare IL-4 positive lymphoid cells or dendritic cells were identified. Thus, the study demonstrated that adequate amounts of IL-6 are required for an abundant plasma cell reaction, and that an additional source of IL-6 from histiocytes is essential for the formation of Castleman's disease-like changes in lymph nodes involved by HD. Furthermore, IL-4 is not likely to be responsible for the T-lymphocyte reaction in tissues, by a mechanism distinct from that in T-cell-rich B-cell lymphomas.  相似文献   
66.
Two Hodgkin's Reed-Sternberg cell (H-RS) lines, HDLM-1 and KM-H2, have phenotypes and functional properties very similar to those of H-RS cells in tissues. These two types of cells were induced to differentiate with a combination of phorbol ester, retinoic acid, and extracellular matrix. The induced cells displayed the morphology of histiocytes or histiocytelike cells, with a small, round or oval, eccentric nucleus and abundant cytoplasm. In ultrastructural studies, many cytoplasmic projections and rugae were observed. These induced cells exhibited abundant cytoplasmic lysosomal enzymes, such as esterase, acid phosphatase, alpha 1-antitrypsin, or lysozyme. The histiocytic nature of these induced cells was further confirmed by the increased expression of many monocyte/histiocyte markers, including CD11b, CD11c, CD13, CD14, CD15, CD33, CD68, Mac387, and 1E9. In functional tests, the induced cells were shown to produce interleukin-1, tumor necrosis factor, macrophage colony-stimulating factor, and/or prostaglandin E2. Phagocytosis was detected in less than 5% to 10% of the cells when Candida albicans was added to cultures. The results strongly suggest that H-RS cells are related to cells of histiocyte lineage.  相似文献   
67.
Isolates of Escherichia coli from human urinary tract infections frequently express adherence properties found less often among normal intestinal isolates. These properties include adherence to human uroepithelial cells and primary monkey kidney cells, as well as D-mannose-resistant hemagglutination of human erythrocytes, and they are mediated by a pilus type different from type 1. The genes encoding this pilus type (pyelonephritis-associated pili, pap) and those encoding type 1 pili have been cloned from a urinary tract infection isolate of E. coli and transferred to an E. coli K-12 derivative. The recombinant plasmids were found to express functional pili and to endow the new host with all of the adherence properties of the urinary tract infection isolate. Both pilus types were found to be genetically distinct, and unlike the adherence genes from bovine, porcine, and human diarrheal isolates, both were found to be chromosomally encoded.  相似文献   
68.
B cell-activating factor of the tumor necrosis factor family (BAFF/BLys) plays a critical role in B cell survival and immune responses through its three receptors: BAFF receptor (BAFF-R/BR3), transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) and B cell maturation antigen (BCMA). Using specific antibodies, we have investigated the expression of BAFF-R on human tonsillar B cells and their functional roles in naive and germinal center (GC) B cell differentiation. Our studies show that BAFF-R is the dominant receptor on naive B cells. However, three receptors are differentially modulated during in vitro GC-B cell differentiation. BAFF-R expression increased initially and then decreased with a corresponding induction of TACI and BCMA expression during differentiation to plasma cells (PCs). Consistently, blocking of BAFF-R alone with specific mAb inhibited GC-B cell proliferation and PC generation in the early period of their differentiation, whereas depletion of BAFF with TACI-Ig exhibited consistent inhibition throughout the differentiation. Finally, histological and molecular analyses of human tonsil tissue revealed that follicular dendritic cells produce BAFF. In conclusion, BAFF in the GC plays an important role through more than one receptor, and the three known receptors are differentially modulated as GC-B cells differentiate to PCs.  相似文献   
69.
Highly susceptible inbred male C57BL/6 mice were infected with 2 X 10(7) virulent Salmonella typhimurium by intraperitoneal inoculation. Samples of the liver were removed 2 or 3 days post-infection for examination by electron microscopy. Rapid infiltration of polymorphs and macrophages was observed in the site of infection. Visual evidence is presented to confirm the destruction of salmonellae within these inflammatory phagocytes as previously reported. The proliferation of the pathogens occurred in the extracellular locations of sinusoids and early lesions, and within hepatocytes.  相似文献   
70.
This study presents a 12-year-old girl with Wiskott-Aldrich syndrome variant, who developed acute glomerulonephritis without history of transfer factor therapy and the efficacy of splenectomy for the control of the patient's thrombocytopenia. The patient presented with eczema, severe thrombocytopenia and immunodeficiency. The impaired immunity was featured by impaired delayed hypersensitivity and lymphoproliferative response to nonspecific mitogen, low serum IgM, low isohaemagglutinins, recurrent infections and high IgE. She developed hematuria about one month prior to admission. For her severe thrombocytopenia splenectomy was performed and proved to be effective. At the time of splenectomy, renal biopsy was done and showed proliferative glomerulonephritis with coarse granular deposition of immunoglobulins (IgA and IgM) and C3. Electron microscopy demonstrated granular electron-dense deposits in the glomerulus, indicating an immune complex glomerulonephritis.  相似文献   
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