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1.
The finer branches of the biliary tree (FBBT) contain a regenerative compartment. We hypothesized that preservation of the FBBT together with its microvasculature will lead to recovery of biliary damage and prolonged preservation of bile ductules during the development of chronic liver allograft rejection. The interlobular bile ducts, portal bile ductules and extraportal biliary cells with and without microvessels were studied in sequential biopsies in five patients who fulfilled the Banff criteria of early chronic rejection (CR) (imminence group). Biopsies of CR patients (n = 12) served as controls. Biopsies were double immunostained with CD34 (microvessels) and cytokeratin 7 (biliary structures). Proliferation and proangiogenic activity were assessed with Ki67 and VEGF-A immunostaining. Severe damage of bile ducts in the imminence group did not progress to significant bile duct loss. This was associated with a high proliferative activity in all biliary structures and preservation of the microvascular compartment. VEGF-A expression was increased in all but the reperfusion biopsies. In conclusion, both regenerative activity of the FBBT and an intact microvascular compartment are associated with less damage of the biliary tree and could therefore be prerequisites for biliary regeneration.  相似文献   
2.
In most cases of small-cell lung carcinomas (SCLC) phenotypic features compatible with a neuroendocrine differentiation status can be identified by monoclonal (MOC) antibody-based immunohistological procedures. Similar features can be recognized only in a minority of non-SCLC tumors. During a period of 30 months, all diagnostic non-SCLC biopsies (141 cases) were prospectively analysed for the presence of markers indicative for neuroendocrine differentiation. In 31% of all cases, such a presence could be noticed. Neuroendocrine differentiation (50% to 100% positive-staining tumor cells) was recognized more frequently in adenocarcinoma when compared to large-cell and squamous-cell carcinoma (chi 2 = 9.31, 2 degrees of freedom, P less than 0.01). To investigate whether the clinical behavior of these "neuroendocrine" non-SCLC cases mimics SCLC, a multivariate analysis for prognostic factors was performed. Among other prognostic factors, biopsies containing more than 50% positive-staining tumor cells with the MOC antibody-1 (MOC-1) were recognized as negative prognostic factors.  相似文献   
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To detect metastases in the bone marrow of patients with small cell lung cancer, immunofluorescence with a monoclonal antibody detecting a membrane antigen (MOC-1) associated with small cell lung cancer was performed on 53 bone marrow aspirates from 30 patients. In 19 (63%) patients MOC-1 reactive cells were detected. Simultaneous histopathological examination of the bone marrow biopsy specimens detected tumour cells in only six (20%). The method is more sensitive than conventional histochemical staining of bone marrow aspirate and may eventually be able to show additional subgroups, such as patients with limited disease who might benefit from adjuvant radiotherapy or surgery.  相似文献   
5.
The present study documents major histocompatibility complex (MHC) Class I and II expression during early acute rejection of human liver grafts. Serial graft biopsies (pretransplant, time zero, and 1 week) were studied. Ten patients received azathioprine (AZA) and prednisone; the other six patients were treated with quadruple therapy (azathioprine, cyclosporine A, prednisone, and cyclophosphamide). To study the specificity of changes in MHC antigen expression, biopsies of six patients with minor or no morphologic abnormalities served as controls. In addition, phenotypes of inflammatory cells present during rejection were analyzed using a panel of monoclonal antibodies. The results show that during acute rejection expression of MHC Class I and II antigens increased significantly in the AZA-treated patients, in a pattern similar to that seen in the patients treated with quadruple therapy, showing enhanced MHC Class I expression on hepatocytes, bile duct epithelium, and sinusoidal endothelium, and Class II antigen on Kupffer cells and sinusoidal endothelium. Bile duct epithelium was consistently positive for Class II antigen; no significant difference with the nonrejection group was observed. T cells are the predominant inflammatory cells during rejection with equal quantities of CD4+ and CD8+ cells. A majority of the infiltrating T cells show expression of Class II antigen but do not react with anti-interleukin-2 receptor antibody. This may be the result of immunosuppressive therapy or a simple reflection of the temporary expression of interleukin-2 receptors during lymphocyte activation. The authors hypothesize that the induction of MHC antigens on bile duct epithelium leads to rejection whereas the expression on hepatocytes represents an epiphenomenon.  相似文献   
6.
Three mouse monoclonal antibodies (mAb) directed against rat B lineage antigens were produced. The mAb, designated HIS14 (IgG1), HIS22 (IgM) and HIS24 (IgG2b), were characterized for binding to lymphoid and nonlymphoid tissues by immunoperoxidase staining of frozen sections and by (double-) immunofluorescence staining of single cell suspensions from lymphoid organs. HIS14 recognized a pan B cell determinant: it reacted with virtually all cells of each anatomic B cell compartment and with about 95% of surface (s)Ig+ cells in thoracic duct lymph and in suspensions of spleen and lymph nodes. HIS22 and HIS24 detected B lineage-associated antigens expressed by major subpopulations of B cells. HIS22 predominantly stained the lymphocyte corona, but not (or weakly) the germinal centers and splenic marginal zones, whereas HIS24 reacted with both corona and germinal center and not (or weakly) with marginal zone. In accordance with this, substantial proportions of sIg+ cells in spleen cell suspensions did not express HIS22 or HIS24 determinants (20% and 27%, respectively). In bone marrow the vast majority of cytomplasmic mu+ pre-B cells were HIS14+ and HIS24+, and up to one third also HIS22+, indicating an appearance of the determinants early in B lymphocytopoiesis. The antigens recognized by HIS14, HIS22 and HIS24 are lost during the final stage of B cell differentiation: none of the mAb bound to plasma cells. As far as detectable, neither cells of myeloid and erythroid lineages in bone marrow nor thymocytes were stained by HIS14, HIS22, or HIS24. In suspensions of peripheral lymphoid organs (spleen and lymph nodes) but not in thoracic duct lymph, HIS14 and HIS24 labeled a small proportion (12% and 14%, respectively) of Ig- cells. HIS22 did not bind to Ig- peripheral lymphocytes. Reactivity of HIS14, HIS22 and HIS24 with nonlymphoid tissues was virtually absent; HIS22 stained the high endothelial venules in lymph nodes and Peyer's patches. As determined by immunoblotting, the antigenic determinants on lymph node cells recognized by HIS14, HIS22 and HIS24 were present on molecules with an apparent molecular mass of 205 kDa, 210 (and 175) kDa and 205 kDa, respectively, which is similar to the molecular mass of the B cell form of the rat leukocyte common antigen. In addition, the antigens recognized by HIS14, HIS22 and HIS24 co-capped with the leukocyte common antigen. This suggests that each of the three mAb recognize determinants present on the B cell form of the leukocyte common antigen.  相似文献   
7.
A panel of monoclonal antibodies, specific for either protein or carbohydrate components of the leukocyte common antigen (LCA), were used to characterize the expression pattern of different variants of this antigen complex. Immunohistochemical and flow cytometric analysis was carried out on human lymphoid tissues from different anatomical compartments. We found that variations in terminal sialic acid or O-linked sugar moieties were associated with drastic differences in reactivity with some of the CD45R antibodies. For example, the carbohydrate determinants recognized by MT2 (CD45RA) and 2B11 (CD45) were not or were very weakly expressed on germinal center cells, whereas the carbohydrate determinant recognized by MT3 (CD45RB) was not expressed on the majority of mantle zone B cells. On the other hand, KiB3 (CD45RA) reacted with a protein determinant that is normally only exposed on mantle zone B cells but can be uncovered on marginal zone B cells and the CD45RA-positive T-cell subpopulation by enzymatic treatment. The findings suggest that differential biosynthesis and expression of the carbohydrate components of LCA are important mechanisms to generate additional LCA heterogeneity. Similar to the differential usage of the variable region, the exact carbohydrate composition is also linked to the stage of cell development. Heterogeneity in carbohydrate composition of the extracellular domain of LCA appears to enable interactions with different ligands, thereby holding the key to the regulation of LCA cytoplasmic tyrosine phosphatase activity.  相似文献   
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Summary The age and sex distribution and the localization of excised lymph nodes from 206 patients with a nodular variant of Hodgkin's disease with lymphocytic predominance, called nodular paragranuloma, are presented and compared with data on other types of Hodgkin's disease. The age curve of nodular paragranuloma showed a peak in the fourth decade, which was clearly separated from the peak in the third decade exhibited by the nodular sclerosis type of Hodgkin's disease and from the peak in the sixth and seventh decades of the mixed cellularity type. The peak in the age curve of nodular paragranuloma resulted from the high frequency in men in the fourth decade; the female age curve had no peaks. The overall male-to-female ratio was 2.4:1. The age and sex distribution of diffuse paragranuloma was nearly identical to that of nodular paragranuloma, whereas the age and sex distribution of cases of the lymphocytic predominance type other than paragranuloma resembled that of the mixed cellularity type. These data indicate that the lymphocytic predominance type of Hodgkin's disease is not a uniform group and support the view that paragranuloma is a separate entity.  相似文献   
10.
Lymphocyte activation markers CD69 and HLA-DR were studied in metastatic breast and ovarian cancer patients who received active specific immunotherapy (ASI) using cancer vaccines containing the synthetic tumor-associated antigen sialyl-Tn or the Thomsen-Friedenreich antigen conjugated to KLH plus DETOX adjuvant. Breast cancer patients who showed prolonged survival following ASI had lower numbers of total CD69+ and CD4+CD69+ cells prior to ASI compared to patients who died. However, following ASI, the surviving patients showed an increase in CD69+ and CD4+CD69+ cells and the deceased patients showed a decrease. A greater than 50% increase in the percentage of cells bearing the activation marker CD69 is associated with an increase in survival in both ovarian and breast cancer patients. In the surviving breast cancer patients there was a significant decrease in the percentage of non-B lymphocyte HLA-DR+ (CD20?HLA-DR+) cells following cyclophosphamide treatment. A strong positive correlation was found between lymphocyte populations CD20? HLA-DR+ and CD8+CD57+, a putative suppressor cell population. Breast cancer patients who showed a greater than median decrease in CD20?HLA-DR+ lymphocytes following cyclophosphamide treatment had a survival advantage over patients who had less than the median decrease in the percent CD20?HLA-DR+ lymphocytes. © 1995 Wiley-Liss, Inc.  相似文献   
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