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)

The therapeutic use of dendritic cells (DC) in antigen-specific anti-tumor vaccines, requires sufficient numbers of functional DC, the preparation of which should comply with the code of Good Manufacturing Practice. In addition, the expression of tumor specific antigen should be possible in these DC. As a preclinical step, the method reported here was developed in healthy volunteers. Monocytes (Mo) were isolated by leukapheresis from 12 donors, purified by elutriation and then cultured for 6 days in sealed bags in AIM-V serum free medium with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-13 (IL-13). Between 6x10(8) and 1x10(9) immature DC (iDC) could be differentiated from one leukapheresis. Cells displayed a characteristic iDC phenotype (CD1a(+), CD14(-), CD80(+), CD86(+), HLA DR(+), CD83(-)), and had potent allogeneic and antigen dependent autologous T cell-stimulatory capacity. Moreover, iDC could be further differentiated into mature DC by CD40 ligation as assessed by CD83 expression and the upregulation of HLA-DR and costimulatory molecules. After infection with a recombinant adenovirus encoding for beta-galactosidase (betaGal), 50% to 80% of iDC expressed betaGal without toxicity. Adenovirus infection increased the expression of both costimulatory molecules and CD83, and also increased allogeneic stimulatory capacity. Thus, the method developed here allows us to use large numbers of functional iDC as will be required for therapeutic uses in man. These DC can express a transgenic protein.
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PMID:Adenoviral transduction of human 'clinical grade' immature dendritic cells enhances costimulatory molecule expression and T-cell stimulatory capacity. 1091 50

In the present study, we show that endothelial-like cells (ELCs) can develop from human CD14-positive mononuclear cells (CD14 cells) in the presence of angiogenic growth factors. The CD14 cells became loosely adherent within 24 h of culture and subsequently underwent a distinct process of morphological transformation to caudated or oval cells with eccentric nuclei. After 1 week in culture the cells showed a clear expression of endothelial cell markers, including von Willebrand factor (vWF), CD144 (VE-cadherin), CD105 (endoglin), acetylated low-density lipoprotein (AC-LDL)-receptor, CD36 (thrombospondin receptor), FLT-1, which is vascular endothelial cell growth factor (VEGF) receptor-1, and, to a weaker extent, KDR (VEGF receptor-2). Furthermore, in these cells structures resembling Weibel-Palade bodies at different storage stages were identified by electron microscopy, and upon culturing on three-dimensional fibrin gels the cells build network-like structures. In addition, cell proliferation and vWF expression was stimulated by VEGF, and the endothelial cell adhesion molecules CD54 (ICAM-1), and CD106 (VCAM-1) became transiently inducible by tumor necrosis factor-alpha (TNF-alpha). In contrast, the dendritic markers CD1a, and CD83 were not expressed to any significant extent. The expression of CD68, CD80 (B7-1), CD86 (B7-2), HLA-DR and CD36 may also suggest that ELCs might be related to macrophages, sinus lining or microvascular endothelial cells. Taken together, our observations indicate that ELCs can differentiate from cells of the monocytic lineage, suggesting a closer relationship between the monocyte/macrophage- and the endothelial cell systems than previously supposed.
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PMID:Endothelial-like cells derived from human CD14 positive monocytes. 1092 8

We previously reported an increased percentage of CD14+CD16++ monocytes in the peripheral blood of HIV-infected patients but the physiopathological role of this monocyte subset remains unclear. Cells with a CD14+CD16++ phenotype may be obtained in vitro by culturing human peripheral blood monocytes in the presence of GM-CSF, IL-4 and IL-10. In the present study, we compared the phenotypic and functional characteristics of monocytes-derived CD14+CD16++ cells with those of macrophages and dendritic cells. We show that the CD14+CD16++ cells express dendritic cell markers: CD40, CD80, CD86, HLA-DR, CD11b, CD11c, CD18, CD1a, and CD83. Using RNase protection assay, we demonstrate that CD14+CD16++ cell subset expresses a low ratio of IL-1beta/IL-1ra mRNA and expresses IL-6, MIP-1alpha, MIP-1beta, MCP-1, IL-8, RANTES and I-309 transcripts, similar to dendritic cells. CD14+CD16++ cells produce IL-12, MCP-1 and IL-8, as assessed by flow cytometry. Moreover, CD14+CD16++ cells pulsed with different recall antigens induce a potent autologous T cell proliferation. Altogether, these results provide evidence that CD14+CD16++ cells differentiated in vitro from peripheral blood monocytes exhibit dendritic cell characteristics.
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PMID:CD14+CD16++ cells derived in vitro from peripheral blood monocytes exhibit phenotypic and functional dendritic cell-like characteristics. 1094 Aug 76

Peripheral blood mononuclear cells (PBMCs) from 15 newly diagnosed acute myeloid leukemia (AML) patients were cultured in fetal calf serum-free media supplemented with either granulocyte/macrophage-colony stimulating factor (GM-CSF), interleukin (IL)-4 and tumor necrosis factor alpha (TNFalpha), or GM-CSF, stem cell factor (SCF), TNFalpha and transforming growth factor beta (TGFbeta) in order to generate leukemia-derived dendritic cells (DCs). Cultured cells were analyzed by flow cytometry with respect to DC-associated surface molecules (CD1a, CD83, CD40, CD80, CD86, HLA-DR) when they showed significant DC morphology in culture (14 cases). After cultivation, neo-expression or upregulation of CD1a antigen was found in 8 samples, CD83 in 2, CD40 in 14, CD80 in 7, and CD86 in 9. Twelve of 14 AMLs, in which DC morphology could be induced upon cultivation, showed upregulation of at least 2 DC-associated molecules. For induction of DC differentiation. GM-CSF, IL-4 plus TNFalpha was superior in 11 cases, and better results were obtained with GM-CSF, SCF, TNFalpha plus TGFbeta in 3 cases. In 7 of 14 samples tested, a marked increase of the T-cell stimulatory capacity could be demonstrated in the allogeneic mixed lymphocyte reaction. The leukemic origin of in vitro-generated DCs was demonstrated by fluorescence in situ hybridization in a patient with translocation t(15;17). Our results suggest that the use of different culture conditions may extend the number of AML patients in which a differentiation towards the DC lineage can be induced in vitro.
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PMID:Culture requirements for induction of dendritic cell differentiation in acute myeloid leukemia. 1096 83

HLA-DM has been known to be largely absent from the cell surface of antigen-presenting cells, accumulating instead in the intracellular compartment. In this study, we demonstrated that a population of HLA-DM-positive (HLA-DM+) dendritic cells (DCs) can be identified in an in vitro culture of CD34+ bone marrow haematopoietic stem cells. CD34+ bone marrow cells of healthy donors were used to generate DCs with the recombinant human cytokines granulocyte-macrophage colony-stimulating factor (GM-CSF), tumour necrosis factor alpha (TNF-alpha) and stem cell factor (SCF), both with and without interleukin 4 (IL-4). Flow cytometric analysis demonstrated that HLA-DM+ cells comprised 2.5 +/- 0.9% and 1.8 +/- 0.4% of the CD34+ cell-derived progeny in the presence of GM-CSF, TNF-alpha and SCF after 7 d and 14 d of culture respectively. The number of HLA-DM molecules expressed per HLA-DM+ cell on d 7 was significantly higher than that on d 14 (1410 +/- 47 versus 370 +/- 25, P < 0.05). The addition of IL-4 to the cytokines from the commencement of culture increased the proportion of HLA-DM+ cells and increased the number of HLA-DM molecules per HLA-DM+ cell significantly (P < 0.05). Although most of the HLA-DM+ cells expressed CD1a, CD80 or CD86 antigen, only a small proportion of CD1a+, CD80+ or CD86+ cells expressed HLA-DM. About half the HLA-DM+ cells expressed CD83. The addition of IL-4 resulted in a decrease in the expression of CD83 on the HLA-DM+ cells on d 7. Microscopic evaluations of sorted HLA-DM+ cells revealed the characteristic morphological features of DCs. Primary mixed lymphocyte cultures demonstrated that the HLA-DM+ cells elicited a vigorous proliferation of allogeneic T cells. The level of antigen-specific T-cell activation induced by antigen-pulsed, chloroquine-treated HLA-DM+ cells was substantially higher than that induced by HLA-DM- cells (P < 0.05). These results show that HLA-DM can be used as a useful DC lineage-specific marker, as well as a tool for the characterization of DCs and human immunotherapy.
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PMID:Surface expression of HLA-DM on dendritic cells derived from CD34-positive bone marrow haematopoietic stem cells. 1097 96

Although dendritic cells (DC) can be cultured from cord blood (CB) CD34+ progenitor cells, the generation of DC from CB monocytes has not been reported. In this paper, we explored the generation of DC from CB monocytes to establish the simplest way to obtain a substantial number of DC from CB. We isolated monocytes from CB mononuclear cells (CB-MNC) by the plastic adherence method. These adherent cells (monocyte-rich cells) were cultured in RPMI 1640 medium supplemented with 10% fetal bovine serum (FBS) or in serum-free X-VIVO 15 medium (SFM) for 7 days, both of which contained 100 ng/ml granulocyte-macrophage colony-stimulating factor (GM-CSF) and 10 ng/ml interleukin-4 (IL-4) with or without 10 ng/ml tumor necrosis factor-alpha (TNF-alpha) (added at day 5). In the presence of GM-CSF and IL-4, CB-adherent cells became nonadherent, acquired DC morphology, and showed increased expression of CD1a, CD80, CD86, and HLA-DR; they lost membrane CD14 and some cells with the expression of CD83 and CMRF-44 were generated. With the addition of TNF-alpha to these cultures and culturing for further 2 days, the proportion of CD83+ cells was elevated in both the FBS and SFM culture systems, compared with the culture without TNF-alpha. In the culture with TNF-alpha, cells expressing CD1a, CD80, CD86, HLA-DR, and HLA-DQ were markedly increased. TNF-alpha-treated cells were demonstrated to be stronger stimulators for proliferation of both allogeneic CB lymphocytes and PB lymphocytes than were cells not treated with TNF-alpha. The yield of CD83+ DC at day 7 of cultures was 4.9 +/- 1.1 x 10(5) or 3.0 +/- 0.5 x 10(5) per 1.2 x 10(7) CB-MNC plated initially when cultured in FBS or SFM, respectively. These results have shown that a substantial number of mature DC could be generated from CB-adherent cells even by serum-free culture. We then compared these CB-adherent cell-derived DC (CB-DC) with peripheral blood (PB)-adherent cell-derived DC (PB-DC) in cell-surface phenotype and function. We found day 7 CB-DC have lower expression of CD80, CD1a, CD83, and CMRF-44 than day 7 PB-DC, but CB-DC have a similar capacity to stimulate the proliferation of both allo-CB lymphocytes and PB lymphocytes, compared with PB-DC. CB-DC cultured with GM-CSF and IL-4 have almost identical capacity of phagocytosis to take up fluorescein isothiocyanate (FITC)-dextran and Lucifer yellow (LY), compared with PB-DC. In summary, our findings suggest CB adherent cells, when cultured with GM-CSF, IL-4, and TNF-alpha, are a potent source of functional DC. Thus, CB-DC as well as PB-DC may become valuable tools for immunotherapy.
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PMID:Generation of dendritic cells from adherent cells of cord blood by culture with granulocyte-macrophage colony-stimulating factor, interleukin-4, and tumor necrosis factor-alpha. 1098 43

We describe a phenotypically and functionally novel monocyte-derived dendritic cell (DC) subset, designated mDC2, that lacks IL-12 synthesis, produces high levels of IL-10, and directs differentiation of Th0/Th2 cells. Like conventional monocyte-derived DC, designated mDC1, mDC2 expressed high levels of CD11c, CD40, CD80, CD86, and MHC class II molecules. However, in contrast to mDC1, mDC2 lacked expression of CD1a, suggesting an association between cytokine production profile and CD1a expression in DC. mDC2 could be matured into CD83+ DC cells in the presence of anti-CD40 mAbs and LPS plus IFN-gamma, but they remained CD1a- and lacked IL-12 production even upon maturation. The lack of IL-12 and CD1a expression by mDC2 did not affect their APC capacity, because mDC2 stimulated MLR to a similar degree as mDC1. However, while mDC1 strongly favored Th1 differentiation, mDC2 directed differentiation of Th0/Th2 cells when cocultured with purified human peripheral blood T cells, further indicating functional differences between mDC1 and mDC2. Interestingly, the transfection efficiency of mDC2 with plasmid DNA vectors was significantly higher than that of mDC1, and therefore mDC2 may provide improved means to manipulate Ag-specific T cell responses after transfection ex vivo. Taken together, these data indicate that peripheral blood monocytes have the capacity to differentiate into DC subsets with different cytokine production profiles, which is associated with altered capacity to direct Th cell differentiation.
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PMID:Monocyte-derived CD1a+ and CD1a- dendritic cell subsets differ in their cytokine production profiles, susceptibilities to transfection, and capacities to direct Th cell differentiation. 1103 59

Presentation of cell-associated antigen to T cells is a critical event in the initiation of an anti-tumor immune response but it appears to often be deficient or limiting. Here we report an experimental system for stimulation of human T lymphocytes using autologous antigen presenting cells (APCs) and autologous tumor cells. Two types of APCs were prepared from human bone marrow: MC and DC. MC were produced by using GM-CSF and SCF. DC were obtained with the same cytokines plus IL-4. DC and MC were generated in parallel from the same patients and their phenotypes and capacities to prime T lymphocytes were analyzed and compared. MC were CD14+, CD1a-, CD33+ and HLA-DR+. Two populations of DC were defined: immature DC were uniformly CD1a-; mature DC expressed CD1a, CD80, CD86, HLA-DR, CD54 and CD58 but lacked surface CD14. Stimulation of autologous T lymphocytes was studied by measuring their proliferation and cytotoxic function. In more than 80% of our experiments the proliferation of autologous T lymphocytes cocultured with APC pulsed or not with tumor cell lysates was higher than that of T cells cultured alone. DC were more effective than MC in stimulating proliferation of lymphocytes. The capacity of a patient's autologous bone marrow-derived APC to stimulate T cells when exposed to autologous tumor cell lysates suggest that such antigen-exposed APC may be useful in specific anti-tumor immunotherapy protocols.
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PMID:In vitro immunization of patient T cells with autologous bone marrow antigen presenting cells pulsed with tumor lysates. 1107 49

The 5-lipoxygenase (5-LO) pathway in human CD34(+) hematopoietic progenitor cells, which were induced to differentiate into dendritic cells (DCs) by cytokines in vitro and in DCs of lymphoid tissues in situ, was examined. Extracts prepared from HPCs contained low levels of 5-LO or 5-LO-activating protein. Granulocyte-macrophage colony-stimulating factor (GM-CSF) plus tumor necrosis factor-alpha (TNF-alpha) promoted DC differentiation and induced a strong rise in 5-LO and FLAP expression. Fluorescence-activated cell sorter (FACS) analyses identified a major DC population coexpressing human leukocyte antigen (HLA)-DR/CD80 and monocytic or Langerhans cell markers. Transforming growth factor-beta1 (TGF-beta-1), added to support DC maturation, strongly promoted the appearance of CD1a(+)/Lag(+) Langerhans-type cells as well as mature CD83(+) DCs. TGF-beta-1 further increased 5-LO and FLAP expression, recruited additional cells into the 5-LO(+) DC population, and promoted production of 5-hydroxyeicosatetraenoic acid and leukotriene B(4) in response to calcium (Ca(++)) ionophore A23187. These in vitro findings were corroborated by 5-LO expression in distinct DC phenotypes in vivo. Scattered 5-LO and FLAP in situ hybridization signals were recorded in cells of paracortical T-lymphocyte-rich areas and germinal centers (GCs) of lymph nodes (LNs) and tonsil and in cells of mucosae overlying the Waldeyer tonsillar ring. 5-LO protein localized to both CD1a(+) immature DCs and to CD83(+) mature interdigitating DCs of T-lymphocyte-rich areas of LNs and tonsil. As DCs have the unique ability to initiate naive lymphocyte activation, our data support the hypothesis that leukotrienes act at proximal steps of adaptive immune responses. (Blood. 2000;96:3857-3865)
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PMID:5-lipoxygenase expression in dendritic cells generated from CD34(+) hematopoietic progenitors and in lymphoid organs. 1109 70

Dendritic cells (DCs) were prepared from human bronchoalveolar lavage (BAL) cells. We previously reported that, in particular, the CD1a fraction of the low autofluorescent (LAF) cells contains the precursors for DCs: after overnight culture, 40% of the LAF cells change into functionally and phenotypically prototypic dendritic/veiled cells. There are, as yet, no data on the modulatory effects of glucocorticoids (GC) on the maturation and function of such DCs isolated from the human lung. Functional tests (allogeneic mixed lymphocyte reaction: allo-MLR) were therefore performed with CD1a+ LAF cells at different stimulator-to-T-cell ratios and after preincubation with different dexamethasone (DEX) concentrations. DEX caused suppression of the T-cell stimulatory capacity of CD1a+ LAF cells, which was dose-dependent, and more evident at the higher stimulator-to-T-cell ratios. Here, we also show that CD80 and CD86 are normally expressed at low levels on CD1a+ LAF cell-derived DCs compared to other DC populations. This low-level expression of costimulatory molecules is discussed here in relation to the previously reported low-level expression of CD80 (and CD86) on lung DCs in experimental animals. This appears to play a role in a predominant Th2 cell stimulating potential of DC from the lung environment. DEX exposure of CD1a+ LAF cells prevented the upregulation of even this low-level expression of CD80 and CD86. The veiled/dendritic morphology and the expression of other relevant cell surface markers and adhesion molecules was not affected by DEX exposure. It is concluded that DEX hampers the maturation of CD1a+ LAF cells into active lung DCs.
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PMID:Glucocorticoids hamper the ex vivo maturation of lung dendritic cells from their low autofluorescent precursors in the human bronchoalveolar lavage: decreases in allostimulatory capacity and expression of CD80 and CD86. 1109 Dec 80


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