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)

CD1 proteins are a family of cell surface molecules that present lipid antigens to T cells. We investigated skin dendritic cells and monocyte-derived dendritic cells for expression of CD1 molecules using a panel of 10 different monoclonal antibodies focusing on the recently described CD1d molecule. By immunohistochemical analysis, CD1d expression in normal human skin was restricted to dendritic appearing cells in the papillary dermis mainly located in a perivascular localization. Langerhans cells did not show detectable CD1d expression in situ. Epidermal/dermal cell suspensions analyzed by flow cytometry demonstrated distinct subpopulations of HLA-DR positive dermal dendritic cells expressing CD1a, CD1b, and CD1c. CD1d was expressed on HLA-DRbright dermal antigen-presenting cells in dermal suspensions (16% +/- 3.6%), as well as on highly enriched dermal dendritic cells migrating out of skin explants (60.5% +/- 8.0%). Migrated mature dermal dendritic cells coexpressed CD83 and CD1d. Western blot analysis on microdissected skin sections revealed the presence of a 50-55 kDa CD1d molecule in dermis, suggesting that CD1d is highly glycosylated in skin. Both immature and mature monocyte-derived dendritic cells cultured in autologous plasma expressed CD1d molecules. In contrast, culture in fetal bovine serum downregulated CD1d expression. In conclusion, antigen-presenting cells in skin express different sets of CD1 molecules including CD1d and might play a role in lipid antigen presentation in various skin diseases. Differential expression of CD1 molecules depending on culture conditions might have an impact on clinical applications of dendritic cells for immunotherapy.
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PMID:Cd1d is expressed on dermal dendritic cells and monocyte-derived dendritic cells. 1156 62

Tumour-derived factors suppress differentiation and function of in vitro generated DC. Here, we investigate the effect of two melanoma clones differing in their invasive and metastatic properties on the generation and/or functional maturation of human epidermal LC. LC were generated from CD34(+) cord blood progenitors under GM-CSF/TNF-alpha/TGF-beta 1. CD34(+) cells were co-cultured with or without melanoma cells using Transwell dishes. After 11 days of co-culture, CD34(+)-derived cells display a non-adherent undifferentiated morphology, a high level of monocytic CD14 marker, a down-regulated expression of LC markers (CD1a, E-cadherin) and DC markers (CD40, CD80, CD54, CD58, CD83, CD86, HLA-DR, HLA-class I). These cells were less potent than control LC in inducing allogeneic T cell proliferation. The generation of the CD14(+) population was correlated with a decrease in the CD1a(+) population, without any statistical differences between the two clones. Melanoma cells diverted the differentiation of CD34(+) cells towards a dominant CD14(+) population only if the progenitors were in an early growth phase. IL-10, TGF-beta 1 and VEGF were not responsible for these effects, as assessed by using blocking antibodies. By contrast, co-culture of fresh epidermal LC with melanoma cells did not affect their phenotype and function. Our data demonstrate that melanoma cells inhibit the earliest steps of LC differentiation, but failed to affect the functional maturation of epidermal LC. This suggests that melanoma cells participate in their own escape from immunosurveillance by preventing LC generation in the local cutaneous microenvironment.
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PMID:Human melanoma cells inhibit the earliest differentiation steps of human Langerhans cell precursors but failed to affect the functional maturation of epidermal Langerhans cells. 1174 38

The skin is a unique organ that contains two different subsets of dendritic cells, i.e., Langerhans cells and dermal dendritic cells. Our hypothesis is that cutaneous fibroblasts may affect the development of these dendritic cells. We cocultured cord blood CD34+ hematopoietic progenitor cells with several human cutaneous fibroblast cell lines without any exogenous cytokines for 3 wk. In this culture, hematopoietic progenitor cells increased in number from 20.1 +/- 2.4 times, and produced aggregates of cells with dendritic processes. They were composed of 54.9 +/- 3.2% HLA-DR+ CD14+ CD1a-- cells and 13.8 +/- 3.6% HLA-DR+ CD1a+ cells, which also expressed CD11b and CD11c. There were significant numbers of factor XIIIa+ cells in the culture, whereas no Lag+ or E-cadherin+ cells were detected, and they were potent stimulators in allogeneic T cell activation. There was a significant difference in the ability to induce CD1a+ cells among different human cutaneous fibroblast cell lines. These CD1a+ cells lacked the expression of CD80, CD86, or CD83. In addition, half of them still expressed CD14. When these dendritic cells were cultured with tumor necrosis factor-alpha, however, they became mature dendritic cells with augmented expression of CD86 and CD83 and with increased allogeneic T cell stimulation. The subsequent experiment using a dividing chamber, enzyme-linked immunosorbent assay for granulocyte-macrophage colony-stimulating factor and macrophage colony-stimulating factor, and the blocking studies with antibodies for these cytokines suggested that both the presence of direct contact between hematopoietic progenitor cells and human cutaneous fibroblast cell lines and macrophage colony-stimulating factor produced by human cutaneous fibroblast cell lines are required for their maximum growth and differentiation into CD1a+ dendritic cells, whereas macrophage colony-stimulating factor was solely responsible for their differentiation. These data suggest that cutaneous fibroblasts support the differentiation of dermal dendritic cells in addition to that of monocytes from hematopoietic progenitor cells by their direct contact with hematopoietic progenitor cells and by their macrophage colony-stimulating factor production.
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PMID:Cord blood CD34+ cells differentiate into dermal dendritic cells in co-culture with cutaneous fibroblasts or stromal cells. 1187 84

CD34+ cell-derived hematopoietic precursors amplified with FLT3-ligand, thrombopoietin and stem cell factor became, after a 6-day induction with GM-CSF, IL-4 and TGF-beta1, HLA-DR+, CD1a+, CD83-, CD86-, CD80- cells. A fraction of them expressed Langerin, Lag, and E-cadherin, resembling epidermal Langerhans cells (LC). TNF-alpha added for the last 3 days only marginally induced CD83 expression, but strikingly increased the proportion of immature Langerin+CD83- LC. Langerin+CD83+ and Langerin+CD83- cells were functionally distinct, the former internalizing less efficiently Langerin than the latter. Both CD1a-CD14- and CD1a-CD14+ cells sorted from FLT3-ligand, thrombopoietin and stem cell factor cultures responded to TNF-alpha by an increase of Langerin+ cells. Thus, TNF-alpha rescued LC precursors irrespective of their commitment to the monocytic lineage. When added to GM-CSF, IL-4 and TGF-beta1 containing-cultures, LPS or IL-1beta also induced significant numbers of Langerin+CD83- immature cells displaying a low allostimulatory activity, while CD40-ligand largely promoted highly allostimulatory Langerin-CD83+ cells. Altogether, these data show that in contrast to CD40-ligand, which induced LC maturation even in presence of TGF-beta1, nonspecific proinflammatory factors such as TNF-alpha, IL-1 or LPS, essentially induced immature LC generation, and little cell activation in the presence of TGF-beta1.
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PMID:TNF-alpha induces the generation of Langerin/(CD207)+ immature Langerhans-type dendritic cells from both CD14-CD1a and CD14+CD1a- precursors derived from CD34+ cord blood cells. 1288 72

Current therapy of multiple sclerosis (MS) with interferon-beta (IFN-beta) or glatiramer acetate (GA) has modest effects on the course of MS. Both compounds affect several immune variables, like expression of cell surface molecules and cytokine levels. Here we compared untreated MS, therapy with IFN-beta alone and combined with GA, and healthy controls (HC), regarding expression on HLA-DR+ blood mononuclear cells (MNC) of CD1a that is a cell surface molecule with capacity to present glycolipids to T cells, and of CD80 and CD86 which are costimulatory molecules that activate Th1 and Th2 responses. Cytokine production by MNC was also measured. Flow cytometry and ELISA were used. Cross-sectional comparisons revealed that untreated MS patients had higher CD1a+ HLA-DR+ MNC and lower IL-10 production compared to patients treated with IFN-beta or IFN-beta+GA or HC. Untreated MS patients also had higher spontaneous IFN-gamma and IL-12p70 production compared to MS patients treated with IFN-beta+GA or HC, but not when compared to MS patients on monotherapy with IFN-beta. Low CD1a+ HLA-DR+ MNC and low spontaneous production of IL-12p70 and IFN-gamma were more pronounced in patients treated with IFN-beta+GA than with IFN-beta alone. In order to clarify whether these changes reflect disease activity or treatment effects, we performed a follow up study. Nineteen MS patients with disease progression, despite monotherapy with IFN-beta for more than one year; were re-examined after one to three and four to six months of treatment with IFN-beta+GA. This combination therapy was associated with normalization of CD1a+ HLA-DR+ MNC, IL-12p70 and IFN-gamma. It remains to be shown whether these immunological changes imply a clinical benefit. Follow up studies of immune variables versus clinical effects during combined therapy of MS with IFN-beta+GA are ongoing.
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PMID:Multiple sclerosis: expression of CD1a and production of IL-12p70 and IFN-gamma by blood mononuclear cells in patients on combination therapy with IFN-beta and glatiramer acetate compared to monotherapy with IFN-beta. 1476 Sep 48

To treat leukemia relapse after allogeneic hematopoietic stem cell transplantation (HSCT), we investigated the possibility of immunotherapy using donor CD8+ T cells that were generated by stimulating leukemic cell-derived dendritic cells (leukemic-DCs) or leukemic cell lysate pulsed donor cell-derived DCs (donor-DCs). Leukemic- and donor-DCs were generated from mononuclear cells of patients and CD14+ cells of HLA-matched donors, respectively. The expression of CD80, CD83, CD86, CD1a, and CD40 on leukemic-DCs was significantly lower than that on donor-DCs. Donor-DCs exhibited a higher capacity to stimulate allogeneic T cells compared with leukemic-DCs. Donor CD8+ T cells stimulated by leukemic- or donor-DCs were more cytotoxic than unprimed CD8+ T cells, and slightly higher cytotoxicity was observed with donor-DCs compared to leukemic-DCs. This study indicates that leukemic- or donor-DCs pulsed with leukemic cell lysates can effectively prime donor cytotoxic T cells in vitro, and that they may be used as a potential alternative tool for treating leukemic patients who relapse after allogeneic HSCT.
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PMID:Generation of cytotoxic donor CD8+ T cells against relapsing leukemic cells following allogeneic transplantation by stimulation with leukemic cell- or leukemic lysate pulsed donor cell-derived dendritic cells. 1506 5

The aim of this work was to study the influence of nitric oxide (NO) in the differentiation of human monocytes to dendritic cells. Human monocytes from healthy donors were differentiated to immature dendritic cells in presence of GM-CSF and IL-4. Maturation of dendritic cells was achieved with GM-CSF and TNF-alpha. Nitric oxide donors (SIN-1, DEA-NO or DETA-NO) were added during differentiation of monocytes to dendritic cells and also during dendritic cells maturation. Immature dendritic cells showed a characteristic phenotype CD80+ CD1a+ HLA-DR+ CD86+ CD40+ CD14(low/-), different from adherent monocytes CD80- CD1a- HLA-DR+ CD86+ CD40- CD14++. The addition of SIN-1 the first day of monocyte differentiation reduced cell viability and increased the percentage of apoptotic immature dendritic cells. Peroxynitrite donor, SIN-1, produced more toxic effects than DEA-NO or DETA-NO. An increase in the subpopulation CD1a+ CD80+ HLADR+ of immature dendritic cells was observed when SIN-1 or DEA-NO, but not DETA-NO, was added at the beginning of monocyte culture. There was a significant reduction in the expression of TNF-alpha receptor of mature dendritic cells when SIN-1 and DEA-NO were added together GM-CSF and TNF-alpha at the beginning of maturation. The presence of SIN-1, DEA-NO or DETA-NO in maturation induced an increase of CD83+ cells. These results suggest that nitric oxide affects differentiation and maturation of dendritic cells and this effect depends on the nitric oxide donor used.
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PMID:Effect of nitric oxide in the differentiation of human monocytes to dendritic cells. 1513 4

Using human skin explants, we investigated the effects of two different sunscreen preparations containing a chemical UVB filter alone [sun protection factor (SPF) 5.2] or UVA+UVB filter [SPF 6.2] on sunburn cell formation, dendritic cell (DC) migration, CD86- and CD1a-positive cell number, and tumor necrosis factor alpha (TNFalpha) and interleukin (IL)-1, IL-10, and IL-12 production in the skin after irradiation with different doses of solar-simulated UV radiation. Sunscreen- or placebo-treated skin explants were irradiated with solar-simulated UV radiation at 0.5, 1, and 2 minimal erythematous dose equivalents (MEDE) (as determined in an in vivo human study) multiplied by the SPF of the placebo or sunscreens. After irradiation, skin explants were floated on RMPI medium for 48 h. Cells that had emigrated and the skin explants were histologically analyzed, and the soluble mediators were measured in the supernatants by ELISA. Exposure to UV radiation led to concentration-dependent increases in sunburn cell formation and TNFalpha production but a concentration-dependent decrease in DC migration and CD86- and CD1a-positive cell number in the epidermis. Both chemical sunscreens protected against those alterations. The immunoprotective capacity of the sunscreens correlated with their SPF but was independent of the sunscreens' UVA protection capacity, suggesting that UVA is not a major factor for immunosuppression under the conditions used in the model. UV irradiation did not significantly affect the vitality of emigrated DC; the expression of HLA, CD80, and lag on emigrated cells; the number of CD1a-positive cells in the dermis; or the production of IL-1, IL-10, and IL-12. We conclude that our model may be useful in determining the immunoprotective capacity of sunscreens.
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PMID:Sunburn cell formation, dendritic cell migration, and immunomodulatory factor production after solar-simulated irradiation of sunscreen-treated human skin explants in vitro. 1537 85

Most currently used systems for dendritic cell (DC) production from progenitors entail tumor necrosis factor alpha (TNF-alpha) at the onset of cell culture, based on the notion that TNF-alpha might be required in the early stages of DC development. To optimize conditions for DC expansion from cryopreserved cord blood (CB) CD34+ hematopoietic progenitors, we took a dynamic approach to define the timing of TNF-alpha exposure to the culture. We cultured cord blood CD34+ cells in RPMI-1640 with 10% human AB plasma, stem cell factor (days 1-6), granulocyte-macrophage colony-stimulating factor (days 1-18), interleukin-4 (days 6-18) and varying schedules of TNF-alpha (0-144 h after thawing). Expression of the DC-associated markers, including CD83/CD1a, HLA DR/CD86/CD80, CD14/CD40, was monitored every 3 days. Our data demonstrate that delayed TNF-alpha exposure by 48-72 h after thawing gave rise to two- to three-fold increase in the yield of CD83+ DCs that were highly active in stimulating allogeneic T-cell proliferation compared to immediate TNF-alpha exposure. Thus, the immediate exposure of cryopreserved cord blood CD34+ cells to TNF-alpha, potentially compromising DC expansion, should be avoided. This finding should be of significant consideration when using cryopreserved CD34+ progenitor cells as a source of immunologically competent DCs in a clinical setting.
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PMID:Implication of delayed TNF-alpha exposure on dendritic cell maturation and expansion from cryopreserved cord blood CD34+ hematopoietic progenitors. 1554 Dec 86

The role of endogenously produced cytokines and growth factors in the impaired healing of chronic leg ulcers remains uncertain. The aim of this study was to determine the functional capacity of skin cells in ulcer bed tissue compared to those in the edge of ulcers and skin distal to ulcers. Biopsies from leg ulcers of ten randomly selected patients were examined immunohistochemically for cytokines and growth factors produced by keratinocytes (KC) and vascular endothelial cells (EC). The phenotype of leukocytes infiltrating venous ulcers and the expression of vascular adhesion molecules responsible for extravasation were also studied. The expression of cytokines and growth factors by KC was similar in areas adjacent and remote from an ulcer. In the dermis adjacent to an ulcer, the expression of IL-1alpha, IL-1beta, IL-1Ra, EGF and PDGFa by EC was higher than the levels of expression in EC from the distant dermis. The expression of IL-6, TNFalpha and GM-CSF was comparable to that in cells from intact dermis. For all these factors staining was cytoplasmic, suggesting production in these areas. Ulcer bed tissue contained few fibroblasts and blood capillaries showing a high staining intensity for CD62E and CD106 EC adhesion molecules but no FGF2 expression (P<0.05). The intensity of staining for scavenging CD15+ elastase+ granulocytes and CD35+ (C3bR) activated macrophages in the ulcer bed was comparable to that in the margin but higher than that in the distant dermis (P<0.05), whereas staining for CD68+, HLA DR+, TGFbeta+ and CD54+ dermal macrophages was similar in all areas. There was reduced staining for CD4+ and CD8+ cells in the ulcer bed (P<0.05). There were no CD1a+ Langerhans cells in the epidermis encroaching upon the granulation tissue and there was reduced CD1a staining in the adjacent epidermis (P<0.05). In conclusion, there is chronic accumulation of scavenging cells with lack of remodeling of the granulation tissue and, at the same time, preserved cytokine and growth factor secretory potential of KC and dermal EC in non-healing venous leg ulcers.
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PMID:Keratinocyte and dermal vascular endothelial cell capacities remain unimpaired in the margin of chronic venous ulcer. 1556 1


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