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Shepherd SV, Schmitt D, Platt ML. Visual orienting strategies in freely-moving primates. J Vis 2004. [DOI: 10.1167/4.8.658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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77
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Staquet MJ, Sportouch M, Jacquet C, Schmitt D, Guesnet J, Péguet-Navarro J. Moderate skin sensitizers can induce phenotypic changes on in vitro generated dendritic cells. Toxicol In Vitro 2004; 18:493-500. [PMID: 15130607 DOI: 10.1016/j.tiv.2003.12.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2003] [Accepted: 12/04/2003] [Indexed: 11/25/2022]
Abstract
In the present study, we analyzed the phenotypic alterations induced by several allergens on immature dendritic cells (DC), with the aim to develop a potential in vitro alternative for predicting the sensitizing potential of chemicals. DC were generated from human monocytes cultured in the presence of GM-CSF, IL-4 and TGF-beta1 and treated for 2 or 4 days with different chemicals. Surface marker expression (HLA-DR, CD1a, CD40, CD54, CD83, CD86, CCR7 and E-cadherin) was analyzed by flow cytometry. Results showed that a 2-day treatment with the representative allergens DNCB and NiSO(4) induced significant changes of most antigens while other chemicals such as balm of Peru (strong allergen), kathon (moderate allergen), cinnamic aldehyde (mild allergen) or the irritant SLS had no significant effect. In contrast, the 4-day treatment with allergens substantially improved the results. Indeed, despite a large variability according to the donors, the number of modified antigens was significantly higher with all the tested chemicals, except kathon, as compared to that observed with the irritant SLS. The present study indicates that, in this model, the screening of mild or moderate allergens requires both the consideration of many antigens and a prolonged time of incubation with the chemicals.
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Staquet MJ, Piccardi N, Piccirilli A, Vincent C, Schmitt D, Msika P. Novel Protein Kinase C and Matrix Metalloproteinase Inhibitors of Vegetable Origin as Potential Modulators of Langerhans Cell Migration following Hapten-Induced Sensitization. Int Arch Allergy Immunol 2004; 133:348-56. [PMID: 15031608 DOI: 10.1159/000077354] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2003] [Accepted: 01/07/2004] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Migration and maturation of epidermal dendritic cells, the Langerhans cells (LC), are central events in the initiation of the cutaneous immune response. LC migration from skin to draining lymph nodes is regarded as an indispensable step for the early phase of antigen-specific sensitization. Among the several agents which influence the ability of LC to migrate, previous studies have revealed that matrix metalloproteinases (MMPs) and protein kinase C (PKC) contribute to promoting LC migration. In this work, we studied the effect of two recently developed PKC and MMPs inhibitors of vegetable origin on the migration of in vitro activated LC. METHODS The migratory capacity of epidermal and in vitro generated LC was assessed using a reconstituted basement membrane assay (Matrigel), mimicking the prerequisite passage through the dermal-epidermal basement membrane on the way to the lymph nodes. RESULTS Contact with chemical allergens, Bandrowski's base or 2,4-dinitrobenzenesulfonic acid (DNBS), triggered migration. In the presence of PKC inhibitors, D-erythro-sphingosine and OX100, or an inhibitor of MMPs, LU105, allergen-induced migration of LC was strongly decreased. The association between OX100 and LU105 was more efficient in modulating the migration of activated LC compared to each molecule tested separately. CONCLUSIONS These results showed that PKC and MMPs inhibitors act in synergy to inhibit the migration of activated epidermal dendritic cells in vitro. They underscore the role of PKC and MMPs inhibitors and suggest they may be of relevance for therapeutically regulating epidermal dendritic cell migration in inflammatory dermatoses.
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Peguet-Navarro J, Dalbiez-Gauthier C, Le Varlet B, Courtellemont P, Schmitt D. Determination of sunscreen immune protection factors using human dendritic cell suspensions. Toxicol In Vitro 2004; 18:359-64. [PMID: 15046784 DOI: 10.1016/j.tiv.2003.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2003] [Accepted: 10/20/2003] [Indexed: 11/30/2022]
Abstract
In a previous study, we have used UVB-irradiated human skin explants and the allostimulatory function of Langerhans cells (LC) to determine immune protection factors (IPF) for sunscreens. We sought here to simplify the model by using either human enriched LC suspensions or in vitro generated dendritic cells from human monocytes (MoDC). LC or MoDC suspensions were irradiated with increasing doses of UVB through a piece of translucent strip recovered or not with the sunscreens. The allostimulatory function of the cells was then analysed in a mixed lymphocyte reaction and the UVB dose providing 50% immunosuppression (D50%) was determined graphically. IPF were determined by the ratio of the D50% value in the presence of sunscreen to that of the vehicle alone. In either experimental conditions, the D50% in the presence of sunscreens was significantly higher (p < 0.01) than that obtained with the vehicle, demonstrating the sunscreen immunoprotective effect. IPF values obtained with either DC suspensions were very similar and quite comparable to those previously obtained in the skin explant model. Thus, the present in vitro model provides easy tools to determine a new important biological parameter for sunscreens, i.e. immune protection.
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Trompezinski S, Berthier-Vergnes O, Denis A, Schmitt D, Viac J. Comparative expression of vascular endothelial growth factor family members, VEGF-B, -C and -D, by normal human keratinocytes and fibroblasts. Exp Dermatol 2004; 13:98-105. [PMID: 15009103 DOI: 10.1111/j.0906-6705.2004.00137.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The vascular endothelial growth factor (VEGF) family includes the related polypeptides VEGF-B, -C and -D, which contribute to endothelial and lymphatic vessel development. The parental VEGF molecule, VEGF-A, has been widely described in the skin, but the other members of the VEGF family have not yet been reported. The aim of our study was to determine whether the two main skin cells, keratinocytes and fibroblasts, expressed VEGF-B, -C and -D in basal condition and after stimulation by either growth factors or the pro-inflammatory cytokine tumour necrosis factor-alpha (TNF-alpha). Reverse-transcription polymerase chain reaction (RT-PCR) analysis on cultured normal human keratinocytes (NHKs) and normal human fibroblasts (NHFs) allowed the detection of different levels of VEGF-B, -C and -D mRNA, in both cell types with similar RT-PCR products in the skin cells. A semi-quantitative evaluation of the VEGF family proteins by dot blot, using the different human recombinant VEGFs, showed different levels of VEGF-B, -C and -D, in NHKs and NHFs. After cell stimulation by growth factors (epidermal growth factor (EGF) and transforming growth factor-beta1 (TGF-beta1) for NHKs and NHFs, respectively), a significant up-regulation of the VEGF family member proteins was observed in NHFs but not in NHKs. Conversely, TNF-alpha did not exert a significant effect. However, we could not detect any transcriptional modification in stimulated cells, whatever the stimulation duration. The addition of cycloheximide to the cell cultures strongly inhibited the increase of VEGF proteins in TGF-beta1-stimulated NHFs. Taken together, the results underline the major role played by NHFs in the elaboration of the VEGF family proteins known to regulate wound healing, chronic inflammation and tumour angiogenesis and lymphangiogenesis.
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Kinast EJ, Antonietti V, Schmitt D, Isnard O, da Cunha JBM, Gusmão MA, dos Santos CA. Bicriticality in FexCo1-xTa2O6. PHYSICAL REVIEW LETTERS 2003; 91:197208. [PMID: 14611614 DOI: 10.1103/physrevlett.91.197208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2003] [Indexed: 05/24/2023]
Abstract
X-ray and neutron-diffraction, dc magnetic susceptibility, magnetization, and specific-heat measurements are reported for FexCo(1-x)Ta2O6 mixed oxides. X-ray refinement indicates homogeneous samples for all the reported concentrations. The neutron-diffraction measurements reveal magnetic structures with double propagation vectors (+/-1/4,1/4,1/4) for CoTa2O6, and (1/2,0,1/2) and (0,1/2,1/2) for FeTa2O6. The latter remain unchanged in the Fe-rich samples, for 0.46< or =x<1.00, while the Co-rich samples show propagation vectors (+/-1/4,1/4,0) for 0.09< or =x<0.46. The temperature vs x phase diagram exhibits a bicritical point at about T=4.9 K and x=0.46. For this concentration, and at low temperatures, the system shows coexistence of both magnetic structures. This novel bicritical behavior is interpreted as induced by competition between the different magnetic and crystallographic structures.
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Chadebech P, Goidin D, Jacquet C, Viac J, Schmitt D, Staquet MJ. Use of human reconstructed epidermis to analyze the regulation of -defensin hBD-1, hBD-2, and hBD-3 expression in response to LPS. Cell Biol Toxicol 2003; 19:313-24. [PMID: 14703118 DOI: 10.1023/b:cbto.0000004975.36521.c8] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Defensins have been identified as key elements of innate immunity against microbial infections. In the present study, human beta-defensin-2 (hBD-2) mRNA and peptide expression were evaluated by RT-PCR and Western blotting in normal human keratinocytes, in function of their stage of differentiation. In proliferating, non-differentiating keratinocytes generated in serum-free, low-calcium medium, a very low hBD-2 mRNA expression was found. A significantly higher expression was detected in high-calcium cultivated keratinocytes grown either as monolayers or as multilayers under submerged conditions. In an air-liquid interface culture of keratinocytes, allowing epidermis to be reconstructed, hBD-2 mRNA expression level was significantly higher than in the other conditions and displayed inter-individual variability as observed in native epidermis. The peptide was detected only in reconstructed epidermis. These results indicate that hBD-2 gene expression in normal human keratinocytes is dependent upon their stage of differentiation. The level of expression of hBD-1 mRNA was lower and that of hBD-3 was higher than that of hBD-2 in reconstructed epidermis. Exposure of reconstructed epidermis to bacterial lipopolysaccharide (LPS) resulted in an average 4-fold increase in hBD-2 mRNA 18 h after challenge, but not of hBD-1 and hBD-3 gene expression. These results show the selective regulation of hBD-2-encoding gene in an organotypic epidermal model, in response to LPS. They also provide evidence that in vitro reconstructed epidermis represents a useful model for studying regulation of expression of beta-defensins after skin challenge with pathogenic microorganisms in conditions as close as possible to the in vivo situation.
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Schmitt D, Saravia F, Frimmel FH, Schuessler W. NOM-facilitated transport of metal ions in aquifers: importance of complex-dissociation kinetics and colloid formation. WATER RESEARCH 2003; 37:3541-3550. [PMID: 12867320 DOI: 10.1016/s0043-1354(01)00525-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The transport of metal ions (Al, Fe, Zn, Pb) complexed by natural organic matter (NOM) was investigated by column experiments. Direct breakthrough of metal-NOM complexes was observed after elution of one bed volume for Al, Fe, and Pb, but not for Zn. This observation cannot be understood assuming local thermodynamic equilibrium in the columns. Hence, a model was developed, taking into account the kinetics of the interactions of metal ions with NOM and the solid phase. Of all possible reactions during passage through the column, the dissociation of the metal-NOM complexes was assumed to be the rate-determining step. Dissociation-rate constants were determined by cation-exchange experiments with a non-NOM-adsorbing cation-exchange resin (Chelex-100). These rate constants were used to predict the migration of metal-NOM complexes in the column experiments. Experimental and modeling results were in good agreement for the bivalent metal ions. Also, the model well predicted the pH dependence of breakthrough of trivalent metal ions and the differences between Al and Fe breakthrough on a qualitative basis. This leads to the conclusion that the dissociation kinetics of metal-NOM complexes is an essential parameter for the estimation of NOM-facilitated metal transport. However, for the trivalent metals, Al and Fe, the model overestimated the direct breakthrough, thus giving a worst case prediction of metal transport. With the help of coupling size-exclusion chromatography to inductively coupled plasma-mass spectrometry, the formation of Al-hydroxide and Fe-hydroxide colloids in addition to NOM complexes was detected. These colloids, which were not considered in the model, were partially filtered off in the column, thus leading to overestimation of metal breakthrough.
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Persat F, Noirey N, Diana J, Gariazzo MJ, Schmitt D, Picot S, Vincent C. Binding of live conidia of Aspergillus fumigatus activates in vitro-generated human Langerhans cells via a lectin of galactomannan specificity. Clin Exp Immunol 2003; 133:370-7. [PMID: 12930363 PMCID: PMC1808778 DOI: 10.1046/j.1365-2249.2003.02222.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Aspergillus fumigatus is the most common aetiological fungus responsible for human pulmonary aspergilloses. This study investigated the primary contact between Langerhans cells (LC), corresponding to dendritic cells present in pulmonary mucosa and live conidia of A. fumigatus. LC play a key role in antigen presentation for initiation of the primary T cell response. In vitro-generated LC (iLC) were differentiated from cultured human cord blood CD34+ cells and incubated at 4 degrees C or 37 degrees C with fluorescein-isothiocyanate (FITC)-stained conidia or control latex beads. In vitro, conidia were shown by microscopy and cytometry to adhere to iLC in a dose- and time-dependent manner. This adhesion was not limited to iLC because interstitial dendritic and other cells also fluoresced in the presence of conidia-FITC. A lectin other than mannose receptor-type lectin was demonstrated to be responsible of conidial binding. Inhibition of binding was observed with heterologous galactomannan and EDTA, indicating a C-lectin-like receptor with galactomannan structure specificity. After binding only a few conidia were internalized in acidic vesicles, as indicated by the cessation of conidial fluorescence. Conidial binding was followed by activation and maturation of iLC, suggesting that LC present in the lung may play a role in cellular host defence against aspergilloses.
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85
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DeLong MJ, Schmitt D, Scott KM, Ramakumar S, Lien YHH. Multicentric papillary renal carcinoma in renal allograft. Am J Kidney Dis 2003; 42:381-4. [PMID: 12900823 DOI: 10.1016/s0272-6386(03)00663-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A renal transplant recipient with 13 years of excellent allograft function was found incidentally to have a malignant mass in his transplanted kidney. After resection, pathological analysis showed 29 separate lesions of renal cell carcinoma. All tumors were confined within the renal capsule. The majority of tumors (21 of 29 tumors) were chromophil basophilic carcinoma with papillary architecture, 5 tumors were clear cell, 2 tumors were mixed cell type, and 1 tumor was chromophil eosinophilic papillary carcinoma. These histological findings are similar to those reported in hereditary papillary renal carcinoma. To our knowledge, this is the first case of multicentric papillary renal carcinoma occurring in the renal allograft. We speculate that the allograft in this case is predisposed to malignant changes because of preexisting genetic mutations, as well as prolonged immunosuppression.
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MESH Headings
- Adenocarcinoma, Clear Cell/etiology
- Adenocarcinoma, Clear Cell/pathology
- Adenocarcinoma, Clear Cell/surgery
- Adult
- Carcinoma, Papillary/etiology
- Carcinoma, Papillary/pathology
- Carcinoma, Papillary/surgery
- Carcinoma, Renal Cell/etiology
- Carcinoma, Renal Cell/pathology
- Carcinoma, Renal Cell/surgery
- Cell Transformation, Neoplastic
- Disease Susceptibility
- Humans
- Immunosuppression Therapy/adverse effects
- Incidental Findings
- Kidney Neoplasms/etiology
- Kidney Neoplasms/pathology
- Kidney Neoplasms/surgery
- Kidney Transplantation
- Male
- Middle Aged
- Neoplasms, Multiple Primary/etiology
- Neoplasms, Multiple Primary/pathology
- Neoplasms, Multiple Primary/surgery
- Nephrectomy
- Polycystic Kidney, Autosomal Dominant/surgery
- Postoperative Complications/pathology
- Tissue Donors
- Transplants/adverse effects
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86
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Sivard P, Dezutter-Dambuyant C, Kanitakis J, Mosnier JF, Hamzeh H, Bechetoille N, Berthier O, Sabido O, Schmitt D, Genin C, Misery L. In vitro reconstructed mucosa-integrating Langerhans' cells. Exp Dermatol 2003; 12:346-55. [PMID: 12930289 DOI: 10.1034/j.1600-0625.2003.00108.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
All three-dimensional in vitro mucosal models constructed, thus far, have only been reconstituted by epithelial cells. We have developed a reconstructed oral and vaginal epithelium that integrates Langerhans' cells (LC), the dendritic cells (DC) of malpighian epithelia. The epithelium was composed of gingival or vaginal keratinocytes seeded on a de-epidermized dermis (DED) and grown in submerged culture for 2 weeks. LC precursors, obtained after differentiation of cord blood-derived CD34+ hematopoietic progenitor cells (CD34+HPC) by granulocyte macrophage-colony stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and Flt3-ligand (Flt3-L), were introduced after 6-8 days of culture into the reconstituted epithelium. The in vitro reconstituted mucosal epithelium formed a multilayered, well-differentiated epithelial structure, confirmed by the immunohistochemical expression of cytokeratins 4, 6, 10, 13, 14, 16 and involucrin. LC were identified in the basal and suprabasal epithelial layers by CD1a antigen, S100 protein and Langerin/CD207 expression, and by transmission electron microscopy. Type IV collagen was expressed at the chorio-epithelial junction, and most ultrastructural features of this junction were visualized by electron microscopy. This in vitro reconstructed gingiva or vagina integrating LC represents interesting models very similar to native tissues. Because LC play an important role in the mucosal immune system, our models could be useful for conducting studies on interactions with pathogenic agents (viruses, bacteria etc.), as well as in pharmacological, toxicological and clinical research.
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Concha M, Vidal MA, Moreno I, Salem C, Figueroa CD, Schmitt D, Péguet-Navarro J. Evidence for modulation of human epidermal differentiation and remodelling by CD40. Br J Dermatol 2003; 148:1105-14. [PMID: 12828736 DOI: 10.1046/j.1365-2133.2003.05300.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND It is widely accepted that CD40 plays a critical role in the regulation of immune response. However, the significance of CD40 expression on normal human keratinocytes is only partially known. OBJECTIVES To perform a morphological re-examination of the role of CD40 on the differentiation of human keratinocytes and remodelling of the epidermis. METHODS Keratinocytes were grown on fibroblasts transfected with the CD40 ligand (CD40L) to investigate the formation of epidermal sheets in culture under the influence of the CD40L. Control experiments were carried out using the same cells but transfected with CD32. Further, three specific anti-CD40 monoclonal antibodies were used as soluble agonists to analyse the effect of CD40 ligation on keratinocyte differentiation. RESULTS Epidermal sheets developing from keratinocytes cocultured with fibroblasts transfected with CD40L but not with CD32 showed an up to 50% reduction in thickness compared with control sheets. This change depended mostly on cellular flattening and a decrease in the number of cell layers, and was coincident with a transient decrease in cell surface CD40 immunoreactivity. On the other hand, normal epidermis, and freshly isolated and cultured keratinocytes revealed a predominant CD40+/Ki-67- phenotype that was demonstrated by double immunocytochemistry. Consistent with these observations, keratinocytes primed with interferon-gamma responded to the three soluble agonists, but not to control IgG1, producing immunoreactive (pro)filaggrin and displaying morphological changes in shape and size equivalent to those seen in differentiated cells. CONCLUSIONS As a whole, our findings provide evidence that CD40+ keratinocytes represent a poorly differentiated population, not actively engaged in the cell cycle, which under specific stimulation is committed towards terminal differentiation.
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Bolot G, Popa I, Paret MJ, David MJ, Schmitt D, Portoukalian J. A set of glycoproteins recognized by A2B5 antibody with major bands at 55 and 76 kDa is overexpressed in human head and neck squamous cell carcinomas. Biochimie 2003; 85:409-12. [PMID: 12770779 DOI: 10.1016/s0300-9084(03)00044-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A2B5 antibody was found to strongly label frozen sections of human head and neck squamous cell carcinomas. The low amount of glycolipids (c-series gangliosides and sulfatides) purified from the same tumors and reactive with A2B5 by immunostaining on thin-layer plates could not account for the high level of tissue labeling. Proteins were extracted from both normal tissues and squamous cell carcinomas and analyzed by Western blot with A2B5 antibody on PVDF membranes. The antibody was found to stain a set of glycoproteins with two major bands at 55 and 76 kDa present in normal tissues and overexpressed in carcinomas. Staining was abolished by prior treatment of the PVDF membranes either with Arthrobacter ureafaciens neuraminidase or with a solution of 10 mM periodate that is known to destroy carbohydrates. Our results show that the carbohydrate epitope recognized by A2B5 antibody can be displayed by both glycolipids and glycoproteins.
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90
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Noirey N, Staquet MJ, Gariazzo MJ, Serres M, Dezutter-Dambuyant C, André C, Schmitt D, Vincent C. Withdrawal of TNF-alpha after the fifth day of differentiation of CD34+ cord blood progenitors generates a homogeneous population of Langerhans cells and delays their maturation. Exp Dermatol 2003; 12:96-105. [PMID: 12631252 DOI: 10.1034/j.1600-0625.2003.00043.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Human cord blood CD34+ progenitors cultured in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta) generate a heterogeneous population of dendritic cells (DC), including Langerhans cells (LC). This combination of cytokines has been shown to be crucial for differentiation into LC. After day 5 of culture, TNF-alpha has been maintained in the medium in most studies despite the observation of spontaneous maturation of LC after day 12. Five-day samples of in vitro differentiated LC were cultured in parallel with or without TNF-alpha. The absence of TNF-alpha was shown to: (1) slow down proliferation without triggering apoptotic cell death, (2) enhance the percentage of LC, (3) delay or abrogate the expression of CD83, CD86, HLA-DR and CD208 molecules, and (4) maintain endocytosis by receptor and macropinocytosis. The withdrawal of TNF-alpha abrogated the spontaneous synthesis of matrix metalloproteinases. At day 12, TNF-alpha-deprived LC were less efficient in allogeneic T cell activation than LC cultivated with TNF-alpha. These data indicate that the suppression of TNF-alpha after day 5 maintains cells in an immature state and provides a population with 80% of LC at day 12.
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Nova D, Le Griel C, Holvoet S, Gentilhomme E, Vincent C, Staquet MJ, Schmitt D, Serres M. Comparative studies on the secretion and activation of MMPs in two reconstructed human skin models using HaCaT- and HaCaT-ras-transfected cell lines. Clin Exp Metastasis 2003; 20:675-83. [PMID: 14713102 DOI: 10.1023/b:clin.0000006816.09548.31] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Matrix metalloproteinases play an important role in tissue regeneration, wound healing and tumor invasion. Our previous studies have shown a higher motility of HaCaT-ras-transfected cells compared with HaCaT or normal human keratinocytes (NHK) in correlation with a higher secretion of MMP-2 (72 kDa) or MMP-9 (92 kDa), according to the medium used for cell cultures. Presently, the expression and activity of MMPs were investigated in two reconstructed skin models, using a dead de-epidermized dermis (DED) or a dermal substitute including living fibroblasts. In all experiments, MMP-9 was essentially secreted by NHK and to a greater extent by HaCaT cells. Its active form (86 kDa) was only detected in both reconstructed skin models according to keratinocyte differentiation. MMP-2 was mainly secreted by living fibroblasts included in the dermal substitute skin model. In this case, its activation was up-regulated when HaCaT cell lines were seeded onto the dermal substitute according to their culture at air/liquid interface as shown for MMP-9. The collagenase MMP-1 and stromelysin-1 (MMP-3), susceptible to activate pro-MMP-2 and -9, respectively, were detected in their inactive form by ELISA. MMP-1 was expressed in both models but MMP-3 required the presence of living fibroblasts. Their activities were not detected using specific fluorogenic substrates. In the skin equivalent model using HaCaT, the extensive secretion and activation of MMP-2 and MMP-9 could explain the defect observed in basal membrane reconstruction, suggesting a direct interaction of HaCaT with fibroblasts.
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Trompezinski S, Denis A, Schmitt D, Viac J. IL-10 is unable to downregulate VEGF expression in human activated keratinocytes. Arch Dermatol Res 2002; 294:377-9. [PMID: 12420107 DOI: 10.1007/s00403-002-0339-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2002] [Revised: 05/22/2002] [Accepted: 07/23/2002] [Indexed: 10/19/2022]
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93
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94
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Staquet MJ, Piccardi N, Msika P, Schmitt D. [Langerhans cell migration. An essential step in the induction of contact hypersensitivity]. Ann Dermatol Venereol 2002; 129:1071-7. [PMID: 12442117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
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95
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Haftek M, Creidi P, Richard A, Humbert P, Schmitt D, Rougier A. Topically applied ascorbic acid helps to restructure chronically photodamaged human skin. Eur J Dermatol 2002; 12:XXVII-XXIX. [PMID: 12120617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
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96
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Schmitt D, Taylor HE, Aiken GR, Roth DA, Frimmel FH. Influence of natural organic matter on the adsorption of metal ions onto clay minerals. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2002; 36:2932-2938. [PMID: 12144270 DOI: 10.1021/es010271p] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The influence of natural organic matter (NOM) on the adsorption of Al, Fe, Zn, and Pb onto clay minerals was investigated. Adsorption experiments were carried out at pH = 5 and pH = 7 in the presence and absence of NOM. In general, the presence of NOM decreased the adsorption of metal ions onto the clay particles. Al and Fe were strongly influenced by NOM, whereas Zn and Pb adsorption was only slightly altered. The interaction of the metal ions with the minerals and the influence of NOM on this interaction was investigated by coupling SdFFF with an inductively coupled plasma mass spectrometer (ICPMS) or an inductively coupled plasma atomic emission spectrometer (ICPAES). Quantitative atomization of the clay particles in the ICP was confirmed by comparing elemental content determined by direct injection of the clay into the ICPMS with values from acid digestion. Particle sizes of the clays were found to be between 0.1 and 1 microm by sedimentation field-flow fractionation (SdFFF) with UV detection. Aggregation of particles due to metal adsorption was observed using SdFFF-ICPMS measurements. This aggregation was dependent on the specific metal ion and decreased in the presence of NOM and at higher pH value.
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Staquet MJ, Peguet-Navarro J, Richard A, Schmitt D, Rougier A. In vitro effect of a spa water on the migratory and stimulatory capacities of human Langerhans calls. Eur J Dermatol 2002; 12:LIX-LXI. [PMID: 12120606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
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Trompezinski S, Denis A, Vinche A, Schmitt D, Viac J. IL-4 and interferon-gamma differentially modulate vascular endothelial growth factor release from normal human keratinocytes and fibroblasts. Exp Dermatol 2002; 11:224-31. [PMID: 12102661 DOI: 10.1034/j.1600-0625.2002.110305.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
IL-4 and interferon-gamma (IFN-gamma) are crucial modulators of the immune system and are reported as active antitumor agents and potent inhibitors of angiogenesis. We investigated the effects of these two cytokines on the expression of vascular endothelial growth factor (VEGF), a mediator of major importance in the angiogenesis associated with inflammation, wound healing and tumor invasion and expressed by activated keratinocytes and dermal fibroblasts. Human keratinocytes (HK) and fibroblasts (HF) derived from foreskins, were further cultured during 24 h in defined medium, supplemented or not with the selected growth factors, EGF and TGF-beta1, respectively, before receiving the addition of either IL-4 or IFN-gamma during 24 and 48 h. In basal conditions, fibroblasts produced smaller amounts of VEGF than keratinocytes; the addition of growth factors to the skin cells induced a drastic increase of VEGF secretion. In HF, the basal level of VEGF secretion was reduced by IFN-gamma and slightly increased by IL-4 whereas in HK, IFN-gamma enhanced the secretion of VEGF after 48 h and IL-4 either tended to reduce VEGF secretion or did not exert any effect. Similar but more significant results were observed in skin cells activated by growth-stimulating factors. The association of IL-4 and IFN-gamma mimicked the effects of IFN-gamma alone both in HF and HK. Taken together, these results indicate opposite effects of IFN-gamma and IL-4 on VEGF expression from normal and activated HF and HK. IL-4 may be considered as a poor modulator of VEGF secretion by dermal and epidermal cells. Conversely, IFN-gamma appears as a prominent and versatile mediator in the desregulated angiogenesis associated with inflammatory skin reactions characterized by a T-helper type 1 cell-mediated response.
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Guironnet G, Dezutter‐Dambuyant C, Bechetoille CVN, Schmitt D, Péguet‐Navarro J. Antagonistic effects of IL‐4 and TGF‐β1 on Langerhans cell‐related antigen expression by human monocytes. J Leukoc Biol 2002. [DOI: 10.1189/jlb.71.5.845] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Guironnet G, Dezutter-Dambuyant C, Vincent C, Bechetoille N, Schmitt D, Péguet-Navarro J. Antagonistic effects of IL-4 and TGF-beta1 on Langerhans cell-related antigen expression by human monocytes. J Leukoc Biol 2002; 71:845-53. [PMID: 11994510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Abstract
In this study, we analyzed the specific effects of transforming growth factor beta (TGF-beta1) and/or IL-4 on monocyte-derived cells. Monocytes were cultured with GM-CSF, GM-CSF/TGF-beta1, GM-CSF/IL-4, or GM-CSF/IL-4/TGF-beta1 before cell morphology, phenotype, and function were assessed. As expected, interleukin-4 is mandatory for monocyte differentiation into potent allostimulatory DC. In its absence, monocyte-derived cells share many phenotypic and functional features with macrophages. However, it is interesting that the cells express E-cadherin, independent of exogenous TGF-beta1, and addition of the cytokine induced CCR6 expression. Most importantly, a subset of monocytes cultured with GM-CSF/TGF-beta1 expresses Langerin, as confirmed by electron microscopy analysis. Langerin engagement with specific monoclonal antibodies induces its internalization and the formation of typical Birbeck granules. Monocytes cultured in GM-CSF/IL-4 did not express the LC markers E-cadherin, CCR6, or Langerin. The simultaneous addition of TGF-beta1 allows most of the cells to express E-cadherin but rarely CCR6 and Langerin. Taken together, the results add further evidence that LC can derive from monocytes and demonstrate an antagonistic effect of IL-4 and TGF-beta1 on monocyte differentiation toward the LC pathway.
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