COPD (chronic obstructive pulmonary disease) is an inflammatory disorder of the airways, which is associated with irreversible airway obstruction. The pathological hallmarks of COPD are destruction of the lung parenchyma (pulmonary emphysema), inflammation of the central airways (chronic bronchitis) and inflammation of the peripheral airways (respiratory bronchiolitis). Tobacco smoking is established as the main aetiological factor for COPD. A maladaptive modulation of inflammatory responses to inhalation of noxious particles and gases is generally accepted as being a key central pathogenic process; however, the precise regulatory mechanisms of the disease are poorly understood. Two cell types are known to be important in immune regulation, namely regulatory T-cells and the newly identified Th17 (T-helper 17) cells. Both types of cells are subsets of CD4 T-lymphocytes and modulate the immune response through secretion of cytokines, for example IL (interleukin)-10 and IL-17 respectively. The present review will begin by describing the current understanding of inflammatory cell involvement in the disease process, and then focus on the possible role of subsets of regulatory and helper T-cells in COPD.
The cellular DNA content was measured from paraffin-embedded material in 134 colorectal cancers from patients in whom the outcome was known. Seventy-two (55 per cent) were found to contain cells with abnormal DNA (DNA aneuploid). The presence of such a population of cells was not related to pathological stage or histological grade. However, only 14 (19 per cent) patients with DNA aneuploid tumours survived 5 years compared with 27 (43 per cent) of patients with diploid tumours (chi 2 = 8.0, P = 0.005). Stepwise logistic analysis showed cellular DNA content to be an important prognostic factor in colorectal cancer, independent of pathological stage and histological grade.
The production of a mouse monoclonal IgM antibody, NCRC-11, raised against human breast carcinoma is described. It has been characterized immunohistologically. The antigen recognised has a wide but highly specific distribution in normal tissues, being virtually confined to the surface of certain epithelial cell types. It is found in some forms of epithelial metaplasia and most epithelial malignancies, particularly adenocarcinomas. The heterogeneity of staining in mammary carcinomas is outlined and is of particular interest. The immunohistological staining distribution of NCRC-11 is similar to other antibodies, including anti-epithelial membrane antigen, which were raised against human milk fat globule membrane. A competition experiment with some of these antibodies, using a flow cytofluorimeter, showed competition with one antibody, LICR LON/M8.
In this study we investigated the in vitro responses of peripheral blood mononuclear preparations and purified monocytes to Clostridium difficile toxin A. In contrast to the responses of T and B cells, exposure to toxin A led to a rapid loss of monocytes in a time-and dose-dependent fashion (the majority of cells were lost within 24 h of exposure to >100 ng of toxin per ml). Transmission electron microscopy, flow cytometry, and fluorescence microscopy after propidium iodide and Hoechst staining showed that cell death in purified preparations of monocytes following exposure to 100 and 1,000 ng of toxin A per ml occurred by apoptosis. Further studies showed that 5,5,6,6-tetrachloro-1,1,3,3-tetraethylbenzimidazole-carbocyanine iodide aggregates were retained within toxin A-exposed monocyte mitochondria, but cytochrome c was released, suggesting that the apoptotic cascade was triggered in the absence of mitochondrial permeability transition. There was also an increase in caspase-3 activity in toxin A-stimulated monocytes. Following exposure to very high concentrations of toxin A (30 g/ml), monocyte cell death was predominantly of the necrotic type, with rapid extracellular release of lactate dehydrogenase. These studies demonstrated that C. difficile toxin A has a cell-specific effect, in which monocytes exhibit greater susceptibility than lymphocytes and their death is induced in a concentration-dependent manner.
Summary Cellular DNA content of primary tumours from 280 patients with operable breast cancer was determined by flow cytometry using nuclei from paraffin sections stained with DAPI, and 199 of these patients were followed for 8-13 years after surgery. Tumours from 67 patients have also been analyzed for their DNA content using single cell suspensions from fresh tumour tissue stained with mithramycin and ethidium bromide, and the results compared with those obtained from paraffin blocks of the same tumours.Overall
The novel, proinflammatory cytokine endothelial monocyte-activating polypeptide-II (EMAP-II) was first found in tumor cell supernatants. EMAP-II is closely related or identical to the p43 auxiliary protein of the multisynthase complex, which is involved in protein synthesis. In vitro, EMAP-II induces procoagulant activity, increased expression of E- and P-selectins and tumor necrosis factor receptor-1, and ultimately, programmed cell death (apoptosis) in cultured endothelial cells. EMAP-II is also chemotactic for monocytes and neutrophils. However, the role of the p43/EMAP-II cytokine form in tumors is not understood. We hypothesized an immune-regulatory role within neoplastic tissues and investigated its effects on lymphocytes. EMAP-II causes a dose-dependent inhibition of proliferation and apoptosis in Jurkat T cells and mitogen-activated peripheral blood mononuclear cells. Coculture with DLD-1 colorectal cancer cells or media conditioned by these cells induces apoptosis in Jurkat cells, which is partially reversed by antibodies against EMAP-II. Our data suggest that EMAP-II constitutes a component of a novel, immunosuppressive pathway in solid tumors, which is not normally expressed outside the cell but in tumors, may be subject to abnormal processing and released from tumor cells.
The prevalence and associations of autoantibodies in Saudi diabetic patients are very similar to those reported for diabetic patients in other ethnic groups.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.