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

The transitional stages in the relationship between sentinel monocytes and messenger dendritic cells that are active in adaptive immunity, are, as yet, unclear. To explore these events, 2-hr adherent peripheral blood mononuclear cells were used either as monocytes, or cultured for 7 days with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) to generate dendritic cells, and the phenotypic features and relationship of the two cell populations was investigated using an extensive panel of monoclonal antibodies (mAbs). The features of the shift from monocyte to dendritic cell were also examined by daily phenotyping during the 7-day culture period. Twenty-five mAbs, most of which recognized known CD molecules, bound both monocytes and dendritic cells equally, whereas 19 mAbs exhibited differential staining. Four molecules not previously reported on dendritic cells were documented: CD87, CD98, CD147 and CD148. Seven cell-surface molecules (HLA-DQ, CD1a, CD13, CD30, CD43, CD63 and CD86) were expressed either at very low levels or not at all on monocytes, but had a strikingly increased expression on dendritic cells, suggesting a role in antigen presentation. The kinetics of monocyte to dendritic cell transition revealed a rapid activation phase within the first 24 hr, with a considerable increase in expression of the activation markers HLA-DR, CD13, CD14 and CD98; this was followed by a down-regulation of CD14 and a more gradual development of the other dendritic cell features over the remaining 6 days, with steady increases in CD1a, CD18, CD43, CD86, HLA-DR and HLA-DQ. Thus, these studies have demonstrated four novel components of the dendritic cell, and have documented the dynamic multistep nature of the process whereby an antigen-presenting dendritic cell phenotype may emerge from a monocyte precursor.
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PMID:From sentinel to messenger: an extended phenotypic analysis of the monocyte to dendritic cell transition. 976 44

We present a simple yet powerful method for the isolation and analysis of exosomes released by antigen-presenting cells (APC). Exosomes are small vesicles (40-90 nm) released by APC, and may have an immuno-regulatory function in vivo. Such exosomes originate from MHC class II peptide loading compartments and, as such, express high levels of MHC Class II. We have utilised magnetic beads, coated with monoclonal antibodies specific for HLA DP, DQ, DR for the specific isolation of exosomes from cell-free supernatants. Beads coated with exosomes are subsequently stained with conjugated antibodies, and analysed by flow cytometry. Characterisation of exosomes by this method demonstrated that exosomes derived from B-lymphocytes express abundant MHC Class I and II molecules. Other immunologically important molecules detected included the co-stimulatory molecules B7.1 (CD80) and B7.2 (CD86). The adhesion molecule ICAM-1 (CD54) was also detected. These exosomes also expressed the B cell marker CD20, and the complement inhibitory protein CD59. The expression of CD63, a lysosomal marker, was variable, and there was no detectable expression of transferrin receptor (CD71). Monocyte derived dendritic cells (cultured for 7 days in GM-CSF/IL-4), demonstrated an immature phenotype, and secreted exosomes with a similar phenotype, with abundant MHC molecules. The expression of CD63 was consistently strong, and the MHC Class I-like molecule CD1a was also present, suggesting a possible function in the presentation of lipid antigens. Again CD59 was expressed suggesting a possible role for APC exosomes in complement regulation. There was no detectable CD71, CD40, CD14, CD20 or CD83. Modification of the extraction protocol allowed a comparative analysis of exosome secretion under various conditions. Treatment of cells with calcium ionophore, or phorbol ester resulted in apparent increases in exosome release, while the phosphatidyl inositol 3-kinase inhibitor, wortmannin, reduced exosome secretion. The immuno-magnetic isolation and analysis of exosomes is a versatile and rapid tool for the analysis of APC exosomes, and may prove a valuable tool for the study of exosome biology.
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PMID:Analysis of antigen presenting cell derived exosomes, based on immuno-magnetic isolation and flow cytometry. 1115 May 47

We examined the expression of various CD coded or not yet defined antigens in human thymus samples using indirect immunoperoxidase and immunoflourescent techniques. Data obtained are presented in concurrence with Clusters of Thymic Epithelial Staining (CTES) classification for various monoclonal antibodies recognizing CD antigens (CD1, CD1a, CD6, CD9, CD14, CD16, CD29, CD30, CD32, CD44, CD45RB, CD47, CD48, CD49a, CD49b, CD49c, CD49d, CD49e, CD49f, CD51, CD53, CD54, CD56, CD57, CD63, CD85, CD95, CD98, CD102, CD103, CD106, CD109, CD146, CD147, CD148, CD151, CD152, CD158a, CD158b, CD164, CD165, CD166) and for monoclonal antibodies 1B10, 5G7, A4, BD46, BLTZ, HP1C5, IND.64, M72, WU947 whose specifities are not yet defined. Some of the mAbs such as CD49f, IND.64 and BD46 are detected as good markers for specific cell types or compartments. Significance of the presence of these antigens on thymic epithelial cells at certain locations is briefly discussed.
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PMID:Antigenic profile of human thymus in concurrence with "Clusters of Thymic Epithelial Staining" classification. 1272 40

The aim of the present study was to investigate the effect of loading dendritic cells (DCs) with HeLa-derived exosomes on cytotoxic T-lymphocyte (CTL) responses, and the cytotoxic effects of CTL responses on the HeLa cell line. Ultrafiltration centrifugation combined with sucrose density gradient ultracentrifugation was applied to isolate exosomes (HeLa-exo) from the supernatant of HeLa cells. Morphological features of HeLa-exo were identified by transmission electron microscopy (TEM), and the expression of cluster of differentiation (CD)63 was detected by western blotting. Next, monocytes were isolated from peripheral blood and cultured with the removal of adherent cells to induce DC proliferation. DCs were then phenotypically characterized by flow cytometry. Finally, MTT assays were performed to analyze the effects of DCs loaded with HeLa-exo on T cell proliferation and cytotoxicity assays to evaluate the effect of CTL responses on HeLa cells. TEM revealed that HeLa-exo exhibit typical cup-shaped morphology with a diameter range of 30-100 nm. It was also identified that the CD63 surface antigen is expressed on HeLa-exo. Furthermore, monocyte-derived DCs were able to express CD1a, suggesting that DC induction was a success. DCs exhibited hair-like protrusions and other typical dendritic cell morphology. Furthermore, DCs loaded with HeLa-exo could enhance CTL proliferation and the cytotoxic activity of CTLs compared with DCs without HeLa-exo (P<0.05). In conclusion, DCs loaded with HeLa-exo may promote T cell proliferation and induce CTL responses to inhibit the growth of cervical cancer cells in vitro.
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PMID:Dendritic cells loaded with HeLa-derived exosomes simulate an antitumor immune response. 2961 26

The Epstein-Barr virus (EBV)-associated gastric carcinoma (EBVaGC) is characterized by the infiltration of lymphocytes and a unique tumor microenvironment. Exosomes from cancer cells are essential for intercellular communication. The aims of this study were to investigate the secretion of EBVaGC exosomes and their physiological effect on dendritic cell maturation in vitro and to characterize dendritic cells (DCs) in EBVaGC in vivo. Western blotting analysis of CD63 and CD81 of exosomes from EBV-infected gastric cancer cell lines indicated an increase in exosome secretion. The fraction of monocyte-derived DCs positive for the maturation marker CD86 was significantly suppressed when incubated with exosomes from EBV-infected gastric cancer cell lines. Immunohistochemical analysis of GC tissues expressing DC markers (S100, Langerin, CD1a, CD83, CD86, and BDCA-2) indicated that the density of DCs was generally higher in EBVaGC than in EBV-negative GC, although the numbers of CD83- and CD86-positive DCs were decreased in the group with high numbers of CD1a-positive DCs. A low number of CD83-positive DCs was marginally correlated with worse prognosis of EBVaGC in patients. EBVaGC is a tumor with abundant DCs, including immature and mature DCs. Moreover, the maturation of DCs is suppressed by exosomes from EBV-infected epithelial cells.
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PMID:Exosomes of Epstein-Barr Virus-Associated Gastric Carcinoma Suppress Dendritic Cell Maturation. 3319 73