Lymphocytes sensitivity to Fas stimulation in healthy and asthmatic children.

Abstract

Abstract:The T cell hypothesis of asthma is based on the concept that the disease is driven and maintained by the persistence of a specialized subset of chronically activated T memory cells sensitized against an array of allergenic, occupational or viral antigens. Overreaction of CD4+ T cells in the peripheral blood and airway tissues is an invariant feature of asthma; therefore a potent mechanism for augmenting the number of activated T cells in this disease would be the resistance to the normally programmed pathway for cell death. The aim of the study was to evaluate the presence of apoptotic markers on peripheral blood lymphocytes from healthy and asthmatic children before and after stimulation with antiCD95 antibodies. The blood was collected from 21 children with atopic asthma suffering from allergic rhinitis because of house dust mite and/or grass pollen allergens and 8 healthy children matched for their age and sex. Blood was mixed with purified monoclonal antibody antiCD95 (Beckman Coulter), incubated for 24 hours and than stained with Annexin V andPI (Becton Dickinson). Prepared suspensions were analyzed with Cytomics FC 500 (Beckman Coulter) flow cytometer. Annexin V(+)/PI(-) cells were characterized as early apoptotic, Annexin V(+)/PI(+) as late apoptotic and Annexin V(-)/PI(+) as dead. In unstimulated sample from asthmatic children 21.09±11.20% cells were characterized as Annexin V positive/PI negative. After stimulation with antiCD95 Annexin V positive/PI negative cells constituted 18.72±9.42% of cells, p=0.1. In unstimulated sample from healthy children 11.69±6.70% cells were characterized as Annexin V positive/PI negative. In the sample stimulated with antiCD95 16.54±2.98% of cells were Annexin V positive/PI negative, p=0.02. There were no differences between results of late apoptotic and necrotic lymphocytes from healthy and asthmatic children. Performed research indicates that lymphocytes from asthmatic children are resistant to Fas mediated apoptosis.

Sublingual immunotherapy in asthma does not influence lymphocyte sensitivity to fas stimulation

“…Those authors have also analyzed the CD95 expression on the cells from sensitized patients after the proper allergen activation. A significant increase has been observed compared with the resting cells (up to 7.5 ± 2.8%), albeit lower than that obtained by us in a previous study (18.0 ± 6.4%) [ 23 ]. Since the Fas pathway is regarded as one of the most important triggers of apoptosis, its relation and influence on the programmed death of analyzed cells should not be ignored and further studies are needed to confirm our observations.…”

“…Since the Fas pathway is regarded as one of the most important triggers of apoptosis, its relation and influence on the programmed death of analyzed cells should not be ignored and further studies are needed to confirm our observations. We have previously shown a significant difference in apoptosis of non-stimulated and Fas-stimulated peripheral blood mononuclear cells from healthy individuals [ 23 ]. Similar results have also been obtained by Jayaraman et al [ 3 ].…”

Synthesis, characterization, and evaluation of cis-diphenyl pyridineamine platinum(II) complexes as potential anti-breast cancer agents

“…Cisplatin was added at 5 μM concentration to MCF 7 and at 10 μM concentration to MDA-MB-231 cells. Cells were stained with fluorescein isothiocyanate (FITC)-conjugated annexin V and propidium iodide (PI) and analyzed by a Cytomics FC 500 flow cytometer [44]. For each sample, data from 10,000 events were recorded [45], and subsequently analyzed.…”