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1.
J Histochem Cytochem ; 48(12): 1667-76, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11101635

ABSTRACT

Studies were undertaken to provide information regarding cell-specific expression of mucin genes and their relation to developmental and neoplastic patterns of epithelial cytodifferentiation. In situ hybridization was used to study mRNA expression of mucin genes in duodenum and accessory digestive glands (liver, gallbladder, pancreas) of 13 human embryos and fetuses (6. 5-27 weeks' gestation), comparing these with normal and neoplastic adult tissues. These investigations demonstrated that the pattern of mucin gene expression in fetal duodenum reiterated the patterns we observed during gastric and intestinal ontogenesis, with MUC2 and MUC3 expression in the surface epithelium and MUC6 expression associated with the development of Brünner's glands. In embryonic liver, MUC3 was already expressed at 6.5 weeks of gestation in hepatoblasts. As in adults, MUC1, MUC2, MUC3, MUC5AC, MUC5B, and MUC6 were expressed in fetal gallbladder, whereas MUC4 was not. In contrast, MUC4 was strongly expressed in gallbladder adenocarcinomas. MUC5B and MUC6 were expressed in fetal pancreas, from 12 weeks and 26 weeks of gestation, respectively. Surprisingly, MUC3 which is strongly expressed in adult pancreas, was not detected in developmental pancreas. Taken together, these data show complex spatio-temporal regulation of the mucin genes and suggest a possible regulatory role for mucin gene products in gastroduodenal epithelial cell differentiation.


Subject(s)
Duodenum/metabolism , Gallbladder/metabolism , Liver/metabolism , Mucins/metabolism , Pancreas/metabolism , Adenocarcinoma/metabolism , Adult , Biliary Tract/metabolism , Duodenum/embryology , Gallbladder Neoplasms/metabolism , Gestational Age , Humans , In Situ Hybridization , Mucins/genetics , Organ Specificity , RNA, Messenger/metabolism
2.
Blood ; 92(12): 4778-91, 1998 Dec 15.
Article in English | MEDLINE | ID: mdl-9845545

ABSTRACT

The escape of malignant cells from the immune response against the tumor may result from a defective differentiation or function of professional antigen-presenting cells (APC), ie, dendritic cells (DC). To test this hypothesis, the effect of human renal cell carcinoma cell lines (RCC) on the development of DC from CD34(+) progenitors was investigated in vitro. RCC cell lines were found to release soluble factors that inhibit the differentiation of CD34(+) cells into DC and trigger their commitment towards monocytic cells (CD14(+)CD64(+)CD1a-CD86(-)CD80(-)HLA-D Rlow) with a potent phagocytic capacity but lacking APC function. RCC CM were found to act on the two distinct subpopulations emerging in the culture at day 6 ([CD14(+)CD1a-] and [CD14(-)CD1a+]) by inhibiting the differentiation into DC of [CD14(+)CD1a-] precursors and blocking the acquisition of APC function of the [CD14(-)CD1a+] derived DC. Interleukin-6 (IL-6) and macrophage colony-stimulating factor (M-CSF) were found to be responsible for this phenomenon: antibodies against IL-6 and M-CSF abrogated the inhibitory effects of RCC CM; and recombinant IL-6 and/or M-CSF inhibited the differentiation of DC similarly to RCC CM. The inhibition of DC differentiation by RCC CM was preceeded by an induction of M-CSF receptor (M-CSFR; CD115) and a loss of granulocyte-macrophage colony-stimulating factor receptor (GM-CSFR; CD116) expression at the surface of CD34(+) cells, two phenomenon reversed by anti-IL-6/IL-6R and anti-M-CSF antibodies, respectively. Finally, a panel of tumor cell lines producing IL-6 and M-CSF induced similar effects. Taken together, the results suggest that the inhibition of DC development could represent a frequent mechanism by which tumor cells will escape immune recognition.


Subject(s)
Antigens, CD34 , Carcinoma, Renal Cell/metabolism , Dendritic Cells/physiology , Interleukin-6/physiology , Macrophage Colony-Stimulating Factor/physiology , Antibodies/pharmacology , Antigens, CD34/metabolism , Cell Differentiation/drug effects , Cell Division/drug effects , Cell Size/drug effects , Culture Media, Conditioned/pharmacology , Dendritic Cells/drug effects , Dendritic Cells/metabolism , Dose-Response Relationship, Drug , Endothelial Growth Factors/immunology , Endothelial Growth Factors/pharmacology , Gene Expression Regulation/drug effects , Humans , Immunophenotyping , Interleukin-6/immunology , Interleukin-6/pharmacology , Lymphokines/immunology , Lymphokines/pharmacology , Macrophage Colony-Stimulating Factor/immunology , Macrophage Colony-Stimulating Factor/pharmacology , Receptor, Macrophage Colony-Stimulating Factor/biosynthesis , Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/biosynthesis , Tumor Cells, Cultured , Vascular Endothelial Growth Factor A , Vascular Endothelial Growth Factors
3.
Mol Immunol ; 35(9): 513-24, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9809579

ABSTRACT

Using a cDNA subtraction technique, a novel member of the immunoglobulin superfamily was isolated from human Dendritic cells (DC). This cDNA which we named DORA, for DOwn-Regulated by Activation encodes a protein belonging to the CD8 family of receptors containing a single V type loop domain with an associated J chain region, a transmembrane region containing an atypical tyrosine residue and a cytoplasmic domain containing three putative tyrosine phosphorylation sites. The hDORA gene has been localised to chromosome 16. From database searches a rat cDNA was identified that encoded a polypeptide with 63% identity to hDORA. The expression of the human cDNA was studied in detail. Northern blot analysis revealed 1.0 kb and 2.5 kb mRNAs in peripheral blood lymphocytes, spleen and lymph node, while low levels were observed in thymus, appendix, bone marrow and fetal liver. No signal was noted in non-immune system tissues. By RT-PCR analysis of hDORA revealed expression in cells committed to the myeloid lineage but not in CD34+ precursors or B cells and low expression in T cells. Expression was also observed in DC, purified ex vivo or generated in vitro from either monocytes or CD34+ progenitors. This was down-regulated following activation both by PMA and Ionomycin treatment and also by CD40L engagement. In situ hybridisation performed on tonsil sections showed the presence of hDORA in cells within Germinal Centers. This structure and expression suggests a function as a co-receptor, perhaps in an antigen uptake complex, or in homing or recirculation of DC.


Subject(s)
Dendritic Cells/immunology , Immunoglobulins/biosynthesis , Membrane Glycoproteins/metabolism , Amino Acid Sequence , Antigen Presentation , Base Sequence , CD40 Ligand , CD8 Antigens , Cloning, Molecular , DNA, Complementary/genetics , Down-Regulation , Germinal Center/chemistry , Hematopoietic Stem Cells/chemistry , Humans , Immune System/chemistry , Immunoglobulins/genetics , Molecular Sequence Data , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Signal Transduction , Tissue Distribution
4.
J Exp Med ; 188(2): 373-86, 1998 Jul 20.
Article in English | MEDLINE | ID: mdl-9670049

ABSTRACT

DCs (dendritic cells) function as sentinels of the immune system. They traffic from the blood to the tissues where, while immature, they capture antigens. They then leave the tissues and move to the draining lymphoid organs where, converted into mature DC, they prime naive T cells. This suggestive link between DC traffic pattern and functions led us to investigate the chemokine responsiveness of DCs during their development and maturation. DCs were differentiated either from CD34(+) hematopoietic progenitor cells (HPCs) cultured with granulocyte/macrophage colony-stimulating factor (GM-CSF) plus tumor necrosis factor (TNF)-alpha or from monocytes cultured with GM-CSF plus interleukin 4. Immature DCs derived from CD34(+) HPCs migrate most vigorously in response to macrophage inflammatory protein (MIP)-3alpha, but also to MIP-1alpha and RANTES (regulated on activation, normal T cell expressed and secreted). Upon maturation, induced by either TNF-alpha, lipopolysaccharide, or CD40L, DCs lose their response to these three chemokines when they acquire a sustained responsiveness to a single other chemokine, MIP-3beta. CC chemokine receptor (CCR)6 and CCR7 are the only known receptors for MIP-3alpha and MIP-3beta, respectively. The observation that CCR6 mRNA expression decreases progressively as DCs mature, whereas CCR7 mRNA expression is sharply upregulated, provides a likely explanation for the changes in chemokine responsiveness. Similarly, MIP-3beta responsiveness and CCR7 expression are induced upon maturation of monocyte- derived DCs. Furthermore, the chemotactic response to MIP-3beta is also acquired by CD11c+ DCs isolated from blood after spontaneous maturation. Finally, detection by in situ hybridization of MIP-3alpha mRNA only within inflamed epithelial crypts of tonsils, and of MIP-3beta mRNA specifically in T cell-rich areas, suggests a role for MIP-3alpha/CCR6 in recruitment of immature DCs at site of injury and for MIP-3beta/CCR7 in accumulation of antigen-loaded mature DCs in T cell-rich areas.


Subject(s)
Cell Movement/immunology , Chemokines/immunology , Dendritic Cells/cytology , Dendritic Cells/immunology , Macrophage Inflammatory Proteins , Receptors, Chemokine/immunology , Cell Differentiation/immunology , Cell Movement/drug effects , Chemokine CCL20 , Chemokine CCL3 , Chemokine CCL4 , Chemokine CCL5/immunology , Chemokine CCL5/pharmacology , Chemokines/pharmacology , Chemokines, CC/immunology , Chemokines, CC/pharmacology , Humans , Macrophage Inflammatory Proteins/immunology , Macrophage Inflammatory Proteins/pharmacology , Receptors, CCR6 , Receptors, CCR7
5.
Eur J Immunol ; 27(10): 2471-7, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9368598

ABSTRACT

Using a cDNA subtraction technique, a novel member of the ubiquitin family was isolated from human dendritic cells. This gene encodes a diubiquitin protein containing tandem head to tail ubiquitin-like domains, with the conservation of key functional residues. Expression of this 777-bp mRNA was restricted to dendritic cells and B cells, with strong expression in mature B cells. Southern blot analysis indicated that a single copy of this gene is present. In situ hybridization on tonsillar tissue showed expression in epithelial cells and isolated cells within the germinal center. With respect to an expressed-sequence tag (EST) this cDNA could be localized to the major histocompatibility complex class I region of chromosome 6. Comparative analysis and the expression pattern of this gene suggests a function in antigen processing and presentation.


Subject(s)
B-Lymphocytes/metabolism , Dendritic Cells/metabolism , Ubiquitins/isolation & purification , Amino Acid Sequence , Base Sequence , Cell Differentiation , Consensus Sequence , DNA, Complementary/genetics , Fetal Blood/cytology , Gene Expression , Genes , Humans , Molecular Sequence Data , Palatine Tonsil/cytology , Polymerase Chain Reaction , RNA, Messenger/biosynthesis , Sequence Alignment , Sequence Homology, Amino Acid , Subtraction Technique , Ubiquitins/biosynthesis , Ubiquitins/genetics
6.
J Exp Med ; 186(6): 837-44, 1997 Sep 15.
Article in English | MEDLINE | ID: mdl-9294138

ABSTRACT

Dendritic cells initiate immune responses by ferrying antigen from the tissues to the lymphoid organs for presentation to lymphocytes. Little is known about the molecular mechanisms underlying this migratory behavior. We have identified a chemokine receptor which appears to be selectively expressed in human dendritic cells derived from CD34+ cord blood precursors, but not in dendritic cells derived from peripheral blood monocytes. When stably expressed as a recombinant protein in a variety of host cell backgrounds, the receptor shows a strong interaction with only one chemokine among 25 tested: the recently reported CC chemokine macrophage inflammatory protein 3alpha. Thus, we have designated this receptor as the CC chemokine receptor 6. The cloning and characterization of a dendritic cell CC chemokine receptor suggests a role for chemokines in the control of the migration of dendritic cells and the regulation of dendritic cell function in immunity and infection.


Subject(s)
Dendritic Cells/immunology , Macrophage Inflammatory Proteins/metabolism , Receptors, Chemokine , Receptors, Cytokine/genetics , Receptors, Cytokine/metabolism , Amino Acid Sequence , Animals , Base Sequence , CHO Cells , Chromosome Mapping , Cloning, Molecular , Cricetinae , DNA, Complementary/genetics , Dendritic Cells/metabolism , Gene Expression , Humans , Hybrid Cells , Molecular Sequence Data , Polymerase Chain Reaction , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptors, CCR6 , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Homology, Amino Acid , Transfection
7.
J Hepatol ; 27(6): 1057-66, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9453432

ABSTRACT

BACKGROUND/AIMS: In recent years considerable advances have been made in our knowledge of human mucin genes. Although analysis of their genomic organization is still in progress, the pattern of their expression in different human mucosae is now fairly well established. However, little is known about their expression in the biliary tree. In this study we determined the pattern of expression of the different human mucin genes in gallbladder biliary epithelial cells, intrahepatic bile ducts and liver. METHODS: Two complementary methods were used: Northern-blot and in situ hybridization analyses. The experiments were performed with eight probes corresponding to MUC1, MUC2, MUC3, MUC4, MUC5AC, MUC5B, MUC6 and MUC7. RESULTS: Our results revealed a strong mRNA expression of MUC3, MUC6 and MUC5B, a weak expression of MUC1, MUC5AC and MUC2, and no expression of MUC4 and MUC7. Surprisingly, MUC3, which was the gene which was most expressed in the biliary tree, was also found in hepatocytes, suggesting another function for the MUC3 protein than that of a secreted mucin. CONCLUSIONS: We conclude that MUC3, MUC6 and MUC5B were the main mucin genes expressed in biliary epithelial cells.


Subject(s)
Gallbladder/metabolism , Mucins/genetics , RNA, Messenger/analysis , Adult , Bile Ducts, Intrahepatic/metabolism , Blotting, Northern , Epithelial Cells/metabolism , Gallbladder/pathology , Humans , In Situ Hybridization , Liver Neoplasms/secondary
8.
Int J Cancer ; 57(6): 875-82, 1994 Jun 15.
Article in English | MEDLINE | ID: mdl-7911458

ABSTRACT

We have studied the cellular content and the extracellular release of cathepsins B and D, and of plasminogen activator, in 2 different tumor cell populations before confluence and after late confluence: the HT-29 colon carcinoma cell line, which contains primarily undifferentiated cells, and a subpopulation derived from this cell line, which contains cells committed to differentiation into mucus-secreting goblet cells after confluence. In both populations, cellular cathepsin-B activity increased after confluence, and latent cathepsin B was found in all culture media. In the parental cell line, cellular cathepsin D activity decreased after confluence; however, cathepsin D was secreted at high levels into the extracellular medium. In contrast, in the subpopulation of cells committed to differentiation, cellular cathepsin D activity increased after confluence, and cathepsin D was not secreted into the extracellular medium, but was immunolocalized in the apical brush border of the differentiated cells. Plasminogen activator of urokinase type was identified by immunocytochemistry. Both subconfluent cell populations, and the post-confluent undifferentiated cell population, produced plasminogen activator activity at similar levels. In contrast, in the differentiated postconfluent cells, the production of plasminogen activator activity was markedly lower. Our data show that the differentiation of HT-29 colon carcinoma cells into mucus-secreting cells impairs the secretion of plasminogen activator and cathepsin D, but does not affect cathepsin B.


Subject(s)
Carcinoma/enzymology , Cathepsin D/metabolism , Colonic Neoplasms/enzymology , Plasminogen Activators/metabolism , Carcinoma/pathology , Cathepsin B/metabolism , Cell Differentiation/drug effects , Cell Line , Colonic Neoplasms/pathology , Dipeptidyl Peptidase 4 , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/metabolism , Humans , Methotrexate/pharmacology , Mucus , Tumor Cells, Cultured
9.
Clin Chem ; 37(2): 296-300, 1991 Feb.
Article in English | MEDLINE | ID: mdl-1993347

ABSTRACT

We describe a disorder in which low-density lipoprotein (LDL)-cholesterol and apolipoprotein B are in low concentration (0.47 mmol/L and 0.28 g/L, respectively) and chylomicrons are still present in plasma after an 18-h fast. The d less than 1.006 fraction was isolated by flotation ultracentrifugation and the apolipoproteins were analyzed by electrophoresis, immunoblotting with anti-apolipoprotein B-100 antiserum, and isoelectric focusing. In the d less than 1.006 fraction of the fasting serum, we found an apolipoprotein B form with the same apparent molecular mass as apolipoprotein B-48 and similar in amount to apolipoprotein B-100 (respective percentages, 46% and 54%). The monosialylated form of the apolipoprotein C-III was severely decreased. After an oral fat load, the repartition of the two species of apolipoprotein B did not change greatly (respective percentages, 60% and 40%), and the concentration of serum triglyceride increased only from 1.20 to 1.65 mmol/L.


Subject(s)
Apolipoproteins B/blood , Cholesterol/blood , Chylomicrons/blood , Hypobetalipoproteinemias/metabolism , Adult , Apolipoproteins A/blood , Child , Chromatography, High Pressure Liquid , Electrophoresis , Female , Humans , Hypobetalipoproteinemias/genetics , Immunoblotting , Isoelectric Focusing , Male , Middle Aged , Phospholipids/blood
10.
Trans R Soc Trop Med Hyg ; 84(6): 792-4, 1990.
Article in English | MEDLINE | ID: mdl-2096509

ABSTRACT

We have studied the serum lipoprotein system in human African trypanosomiasis (Trypanosoma brucei gambiense infection). The study was carried out on 74 Congolense patients suffering from sleeping sickness and 34 Congolense control subjects living in the endemic region of Boko Songho. We have determined the serum concentrations of lipids (triglycerides, cholesterol, phospholipids) and apolipoproteins (apolipoprotein A-I and B), and the separation of serum lipoproteins by electrophoresis. For the patients infected with T. b. gambiense, in comparison with control subjects, the results have shown (i) a significant increase in triglyceride concentration and a decrease in cholesterol concentration; (ii) a significant rise in apolipoprotein B concentration and a significant reduction in apolipoprotein A-I concentration; and (iii) an increase in low density lipoproteins and a decrease in high density lipoproteins. We conclude, therefore, that human African trypanosomiasis is associated with marked alterations in the composition and levels of host lipoproteins.


Subject(s)
Lipids/blood , Lipoproteins/blood , Trypanosoma brucei gambiense , Trypanosomiasis, African/blood , Adolescent , Adult , Aged , Animals , Apolipoproteins/blood , Child , Child, Preschool , Cholesterol/blood , Female , Humans , Lipoproteins, HDL/blood , Lipoproteins, LDL/blood , Male , Middle Aged , Triglycerides/blood
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