Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06126 (CD1a)
 2,221 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Peptides of melanosomal proteins have recently been shown to be recognized in an HLA-restricted mode by specific cytolytic T lymphocytes in melanoma patients. Dendritic antigen-presenting cells (DC) are considered to be the most effective stimulators of T cell responses, and the use of these cells has therefore been proposed to generate therapeutic responses to tumor antigens in cancer patients. We, therefore, generated DC from peripheral blood of normal donors in the presence of granulocyte/macrophage colony-stimulating factor and interleukin-4. Flow cytometric analysis of the cells during a 2-week culture revealed a loss of CD14 and CD34 expression, a concomittent increase of CD1a, CD11a,b and c, CD44, CD45, CD54, HLA-class I and II, and intermediate levels of CD26, CD80 and CD86. Cultured DC stimulated proliferation of allogeneic T cells and induced a marked, up to 20-fold, stimulation of T cell proliferation after pulsing with tetanus toxoid. To achieve independence of already-identified antigenic peptides presented in HLA class I-restricted fashion, which limits the general applicability of such peptides for vaccination of melanoma patients, we tested whether DC are transfectable with eukaryotic expression plasmids. DC transfected with two reporter genes (CAT, beta-galactosidase) using a liposome-based transfection technique, exhibited only low levels of enzymatically active proteins, but were able to degrade rapidly intracellular proteins and to process peptides efficiently. Chloramphenicol acetyltransferase as well as tyrosinase mRNA were detectable after transfection by reverse-transcriptase-polymerase chain reaction, and enzyme activities became measurable. Furthermore, DC transfected with the tyrosinase gene were able to induce specific T cell activation in vitro, indicating appropriate peptide processing and presentation in DC after transfection. These data suggest new approaches to future tumor vaccination strategies.
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PMID:Dendritic cells generated from peripheral blood transfected with human tyrosinase induce specific T cell activation. 748 49

Because activated human macrophages can be potent sources of IL-10, and because immunosuppressive tolerance-inducing macrophages populate the skin after UV exposure, we determined whether IL-10 is induced after UV exposure of human skin and whether it is related to the immigrating macrophages. Keratomes were obtained from control skin or from skin obtained 72 h after a single exposure to four minimal erythemal doses of UVB. Quantitative reverse-transcriptase PCR on total RNA extracted immediately from skin keratomes showed that IL-10 mRNA was elevated in UV-exposed skin. Epidermal cell suspensions from non-UV-exposed keratomes (C-EC) and UV-exposed keratomes (UV-EC) were fractionated by sequential immunobead selection. IL-10 mRNA was reproducibly 200- to 400-fold higher in CD11b+ UV-EC (macrophages) relative to CD11b- UV-EC (keratinocytes). IL-10 mRNA was not detected in C-EC that contained the CD1a+ population (Langerhans cells) nor in CD1a- C-EC keratinocytes from normal skin. As determined by ELISA, CD11b+ UV-EC IL-10 cell-associated protein was fivefold higher than that of CD11b- UV-EC; this was confirmed by flow cytometric visualization of IL-10 protein in permeabilized cells. CD11b+ UV-EC macrophages secreted IL-10 protein into the supernatant at a level of 333 +/- 51 pg/10(6) cells, whereas UV-EC keratinocytes did not secrete detectable levels of IL-10 (n = 3), although UV did induce low levels of IL-10 mRNA and cell-associated protein in keratinocytes. Therefore, although human keratinocytes accumulate intracellular IL-10 after in vivo UV exposure, the most potent production and secretion of IL-10 in the epidermis seems to be that of UV-induced macrophages. Skin-infiltrating macrophage secretion of such a potent immunoregulatory cytokine may account for the delayed immunosuppressive environment of sunburned skin and the altered APC activity of the infiltrating macrophages.
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PMID:CD11b+ macrophages that infiltrate human epidermis after in vivo ultraviolet exposure potently produce IL-10 and represent the major secretory source of epidermal IL-10 protein. 796 79

For therapeutic purposes, large numbers of dendritic cells (DCs) are essential. In this study, we used 2% autologous canine plasma, granulocyte/macrophage colony-stimulating factor (GM-CSF), fms-like tyrosine kinase 3 ligand (Flt3L), and interleukin 4 (IL-4) in generating monocyte-derived DCs from peripheral blood mononuclear cells of dogs. The plasma enriched the population of CD14-positive monocytes by greatly enhancing the efficiency of monocyte adherence, the proportion of adherent cells increasing from 6.6% with 10% fetal bovine serum to 15.3% with 2% autologous canine plasma. Culturing the adherent monocytes for 6 d with human GM-CSF, canine IL-4, and human Flt3L significantly increased the yield of DCs, more than 90% of which were CD14-negative. Because, in the presence of lipopolysaccharide (LPS), monocytes that were CD14-positive expressed tumor necrosis factor ac much more than DCs with low levels of CD14, it is important to decrease the numbers of CD14-positive cells in generating monocyte-derived DCs. With flow cytometry and real-time reverse-transcriptase-mediated polymerase chain reaction assays, we found that in canine immature DCs (iDCs) the expression of DLA class II molecules, CD1a, CD11c, CD40, and CD86 was high and the expression of CD80, CD83, and CD14 either low or negative. During maturation (stimulated by LPS), the expression of CDla, CD40, CD83, and CD80 was upregulated. However, the expression of DLA class II molecules, CD11c, and CD86 was not increased in mature DCs. Incubating the iDCs with LPS decreased antigen uptake and increased the cells' immunostimulatory capacity (assessed by the allogeneic mixed-lymphocyte reaction), indicating that LPS accelerates the functional maturation of DCs. This protocol may facilitate the use of DCs in cellular immunotherapy.
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PMID:Characterization of canine monocyte-derived dendritic cells with phenotypic and functional differentiation. 1769 90