Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P14784 (IL-2 receptor)
 3,849 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We hypothesized that metabolic products of the Alzheimer beta amyloid precursor protein (APP) might be targets for cells of the immune system. To test this hypothesis, peripheral blood lymphocytes from young and old healthy blood donors and patients with Alzheimer's disease were analysed for their responsiveness upon stimulation with amyloid beta protein as well as with four other synthetic peptides corresponding to parts of the APP sequence. Stimulation of resting blood lymphocytes from young and old healthy blood donors resulted in IL-2 receptor expression and proliferation in both age groups. In contrast, lymphocytes from the majority of patients with Alzheimer's disease did not proliferate, when stimulated with APP peptides, while their proliferative response to anti-CD3 was unimpaired. This lack of proliferative responsiveness to APP peptides was not due to apoptosis, but could reflect T cell anergy, as it was accompanied by unimpaired IL-2 receptor expression. The results suggest that autoreactive lymphocytes with specificity for metabolic products of APP occur in healthy individuals. These cells may be of relevance for the elimination of potentially amyloidogenic substances. This mechanism could be impaired in patients with Alzheimer's disease.
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PMID:APP peptides stimulate lymphocyte proliferation in normals, but not in patients with Alzheimer's disease. 883 28

We have previously demonstrated that soluble amyloid beta protein (A beta) induces IL-2 receptor expression and proliferation in peripheral T cells from young and old healthy individuals, but not from patients with Alzheimer's disease (AD). It seemed of interest to examine how the immune system would react upon stimulation with A beta in its aggregated form. It was the aim of this study to define interactions between the spontaneously aggregating A beta (25-35) and antigen-presenting cells. Human dendritic cells (DC), propagated from the peripheral blood of young healthy individuals, were incubated with A beta (25-35) and its effects on DC survival, cytokine release, and surface marker expression were monitored. The question whether DC could present amyloid to T cells was also addressed. We demonstrated that A beta (25-35) does not induce DC apoptosis or necrosis. This was shown by electron microscopy as well as by nuclear staining with propidium iodide. Some peptide aggregates were found in intracellular vacuoles of DC. This process did not increase production of TNF alpha and did not change the surface expression of CD18, CD11a or CD11b. A decreased surface expression of MHC class II molecules was, however, noted. DC pulsed with A beta aggregates were unable to stimulate T cells in an autologous coculture system. The results demonstrate that amyloid may escape immune recognition by its failure to activate antigen-presenting cells and by inhibiting MHC class II surface expression.
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PMID:Interactions of the Alzheimer beta amyloid fragment (25-35) with peripheral blood dendritic cells. 914 74