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1.
Animal ; 16(4): 100491, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35334393

ABSTRACT

Medium-chain fatty acids (MCFAs) have antimicrobial properties and cause negative or positive effects on animal performance depending on its dosage. We hypothesized that MCFA supplementation at a lower dose (i.e., 0.05-0.2% of dietary DM) would increase rumen pH and milk production without decreasing nutrient digestibility which is typically observed with the higher inclusion rates (i.e., >1% of dietary DM). The objective of this study was to evaluate the effects of MCFA supplementation at a lower dose on productivity, plasma energy metabolite concentrations, apparent total tract nutrient digestibility, rumen fermentation, and rumen microbial profile of lactating dairy cows. Thirty (n = 8 primiparous, n = 22 multiparous) Holstein cows in mid-lactation (637 ± 68.5 kg of initial BW, 98.5 ± 27.4 d in milk; mean ± standard deviation) were used in a crossover design with two 28-d periods. The MCFA supplement, consisted of 25% MCFA (containing 32% C8:0, 21% C10:0, 47% C12:0 on DM basis) and 75% carrier ingredients, was fed at 0.25% of dietary DM replacing dry ground corn in control (CON). Total inclusion of MCFA was 0.063% of dietary DM. No differences were observed in DM intake, apparent total tract nutrient digestibility and BW change between MCFA and CON. Milk and milk component yields did not differ between treatment groups. The MCFA supplementation tended to have higher minimum rumen pH (5.66 vs. 5.54), and decreased daily fluctuation range of rumen pH (1.17 vs. 1.40) compared to CON. However, the duration of acidosis (pH < 5.8, min/d) did not differ between treatment groups and ruminal total volatile fatty acid concentration and its profile did not differ between treatment groups. For rumen microbiota, the Chao1 index of bacterial community tended to be lower (10.9 vs. 11.6) whereas the Shannon index did not differ (0.91 vs. 0.93) in MCFA compared to CON, and both indices did not differ for archaeal and protozoan communities between treatment groups. The relative abundance of Methanobrevibacter gottschalkii increased when supplemented with MCFA (5.14 vs. 4.92%). These results suggest that supplementation of MCFA at 0.063% dietary DM may not affect overall animal performance or total tract nutrient digestibility, but decrease the daily range of pH and the bacterial richness in the rumen.


Subject(s)
Lactation , Rumen , Animal Feed/analysis , Animals , Cattle , Diet/veterinary , Dietary Supplements , Digestion , Fatty Acids/metabolism , Female , Fermentation , Milk/metabolism , Rumen/metabolism
2.
Cell Mol Bioeng ; 10(3): 235-248, 2017 Jun.
Article in English | MEDLINE | ID: mdl-31719862

ABSTRACT

Defining the characteristics of cancer stem cells (CSC) has become an important subject in cancer research during the past decade. Although molecular surface expression levels have been used for CSC recognition, the clinical and prognostic impacts of these markers have remained a controversial issue. The finding that cancerous cells are considerably more deformable than normal ones provides the motivation for the hypothesis that the mechanical properties can be used as biomarkers to distinguish between stem-like and non-stem-like cancer cells. In this study, using micropipette aspiration (MA) and intracellular particle tracking (IPT) microrheology, measurements of the whole-cell and local viscoelasticity were made on four breast cancer cell lines with different CSC phenotypes based on their surface markers. Stem-like Hs578T and MDA-MB-231 cell lines were found to be the most deformable, while the non-stem-like MDA-MB-468 line was the least deformable. The non-stem-like BT-20 cell line showed an intermediate deformability. The enhanced deformability for stem-like cells was consistent with the observed lower and more dispersed F-actin content for the stem-like cells. Therefore, the cytoskeleton-related differences in the rheological properties of cancer cells can be a potential biomarker for CSC and eventually lead to novel cancer diagnostic and therapeutic methods.

4.
Mol Psychiatry ; 19(3): 311-6, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24145376

ABSTRACT

Cognitive functions are highly heritable and the impact of complex genetic interactions, though undoubtedly important, has received little investigation. Here we show in an animal model and in a human neuroimaging experiment a consistent non-linear interaction between two genes--catechol-O-methyl transferase (COMT) and dysbindin (dys; dystrobrevin-binding protein 1 (DTNBP1))--implicated through different mechanisms in cortical dopamine signaling and prefrontal cognitive function. In mice, we found that a single genetic mutation reducing expression of either COMT or DTNBP1 alone produced working memory advantages, while, in dramatic contrast, genetic reduction of both in the same mouse produced working memory deficits. We found evidence of the same non-linear genetic interaction in prefrontal cortical function in humans. In healthy volunteers (N=176) studied with functional magnetic resonance imaging during a working memory paradigm, individuals homozygous for the COMT rs4680 Met allele that reduces COMT enzyme activity showed a relatively more efficient prefrontal engagement. In contrast, we found that the same genotype was less efficient on the background of a dys haplotype associated with decreased DTNBP1 expression. These results illustrate that epistasis can be functionally multi-directional and non-linear and that a putatively beneficial allele in one epistastic context is a relatively deleterious one in another. These data also have important implications for single-locus association analyses of complex traits.


Subject(s)
Carrier Proteins/physiology , Catechol O-Methyltransferase/genetics , Catechol O-Methyltransferase/physiology , Epistasis, Genetic , Memory, Short-Term/physiology , Prefrontal Cortex/physiology , Alleles , Animals , Carrier Proteins/biosynthesis , Carrier Proteins/genetics , Catechol O-Methyltransferase/biosynthesis , Dysbindin , Dystrophin-Associated Proteins , Functional Neuroimaging , Gene Expression Regulation/genetics , Gene Expression Regulation/physiology , Homozygote , Humans , Magnetic Resonance Imaging , Male , Maze Learning/physiology , Mice , Mice, Knockout , Mutation
5.
Eur Respir J ; 34(3): 676-86, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19386686

ABSTRACT

We and other investigators have hypothesised that the CXC chemokine receptor (CXCR)3/CXCR3 ligand biological axis is involved in the formation of sarcoid lung granulomas; however, significant discrepancies in the current literature remain. In an effort to clarify previous conflicting findings, we performed the largest observational study to date of interferon-inducible ELR(-) (lacking the sequence glutamic acid-leucine-arginine) CXC chemokines in sarcoid bronchoalveolar fluid (BALF). BALF chemokine levels from sarcoid patients (n = 72) and healthy controls (n = 8) were measured with the ELISA method. Immunohistochemical staining was performed for CXCR3 and its ligands. BALF CXC chemokine ligand (CXCL)10 levels from sarcoid patients were not significantly increased compared with controls. BALF CXCL11 levels from sarcoid patients demonstrated a trend towards elevation; subgroup analysis by stage showed significant BALF CXCL11 elevation in stage I sarcoid patients compared with controls. BALF CXCL9 levels were elevated from sarcoid patients compared with controls. CXC11, CXCL9 and CXCR3 were expressed from epithelioid histiocytes, multinucleated giant cells and other inflammatory cells forming sarcoid lung granulomas. Our data suggest that CXCL9 and CXCL11 are important mediators in recruiting CXCR3-expressing cells. Importantly, we have made the novel observation that both lymphocytes and cells of monocyte linage express CXCR3 and are involved in the formation of sarcoid lung granulomas.


Subject(s)
Chemokines, CXC/metabolism , Receptors, CXCR3/metabolism , Sarcoidosis, Pulmonary/metabolism , Sarcoidosis, Pulmonary/pathology , Adult , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/cytology , Case-Control Studies , Female , Humans , Interferons/physiology , Ligands , Male , Middle Aged , Sarcoidosis, Pulmonary/etiology , Severity of Illness Index
6.
Lung Cancer ; 59(3): 391-4, 2008 Mar.
Article in English | MEDLINE | ID: mdl-17905469

ABSTRACT

Dual time point 2-deoxy-2-[18F] fluoro-d-glucose (FDG) positron emission tomography (PET) imaging has been shown to be useful in helping differentiate benign from malignant lesions. An enhancing mediastinal mass of fat and water density was incidentally detected on computed tomography (CT) in a patient being evaluated for thoracic trauma. He subsequently underwent dual time point FDG PET/CT imaging which revealed a significant rise in standard uptake value (SUV) within the lesion over time, favoring a malignant etiology. Biopsy proved the lesion to represent a hibernoma, an uncommon benign fatty tumor. This case exemplifies the complexity of tissue metabolic properties, and the difficulty in establishing absolute criteria for benign and malignant processes.


Subject(s)
Lipoma/diagnostic imaging , Lipomatosis/diagnostic imaging , Mediastinal Diseases/diagnostic imaging , Tomography, Emission-Computed , Diagnosis, Differential , Fluorodeoxyglucose F18 , Humans , Male , Mediastinal Neoplasms/diagnostic imaging , Middle Aged , Radiopharmaceuticals
7.
Kidney Int ; 71(8): 778-86, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17228365

ABSTRACT

The defense against mucosal infections relies on chemokines that recruit inflammatory cells to the mucosa. This study examined if the chemokine response to uro-pathogenic Escherichia coli is influenced by fimbrial expression. The CXC (CXCL1, CXCL5, CXCL8, CXCL9, CXCL10) and CC chemokines (CCL2, CCL3, CCL5) were quantified after in vitro infection of uro-epithelial cells with a fimbriated E. coli pyelonephritis isolate, or with P or type 1 fimbriated transformants of an avirulent E. coli K-12 strain. The response profile was shown to vary with the fimbrial type. Type 1 fimbriated E. coli elicited mainly CXCL1 and CXCL8, whereas P fimbriated E. coli stimulated CCL2 and CCL5 and class II were more potent chemokine inducers than class III P fimbriae. Chemokines were also quantified in urine samples from 73 patients with febrile urinary tract infection, and analyzed as a function of disease severity and fimbrial expression by the strain infecting each patient. A complex CXC and CC chemokine response was detected in patient urine, with a significant influence of the fimbrial type. The results show that virulence factors like fimbriae may modify the mucosal chemokine response. This mechanism may allow the host to adjust the inflammatory cell infiltrate to fit the infecting strain.


Subject(s)
Chemokines/metabolism , Escherichia coli Infections/metabolism , Escherichia coli/pathogenicity , Fimbriae, Bacterial/metabolism , Urothelium/metabolism , Adhesins, Escherichia coli/genetics , Adult , Aged , Aged, 80 and over , Cell Line , Escherichia coli/genetics , Escherichia coli/metabolism , Female , Fever , Fimbriae Proteins/genetics , Genotype , Humans , Interleukin-8/metabolism , Kinetics , Lectins/metabolism , Male , Middle Aged , Mucous Membrane/metabolism , RNA, Messenger/metabolism , Urinary Tract Infections/metabolism , Urinary Tract Infections/microbiology
8.
Int J Cancer ; 94(6): 783-91, 2001 Dec 15.
Article in English | MEDLINE | ID: mdl-11745478

ABSTRACT

Although it is known that adhesion and antiadhesion are essential to the metastatic spread of tumor cells, little is known about the molecules that regulate these processes. MUC1 is overexpressed and aberrantly glycosylated by a variety of tumor cells. Studies described here examined whether tumor-associated MUC1 conferred new binding properties on tumor cell lines. Flow cytometry analysis with soluble P-, E- and L-selectin/IgM chimeric proteins was performed on human pancreatic (S2-013 and Panc-1) and colon (Caco-2) tumor cells. S2-013 cells bound E- and P-selectin and Caco-2 cells bound P-selectin. Epitope-tagged MUC1 (MUC1F) expressed by S2-013, Panc-1 and Caco-2 tumor cells did not bind to P-, E- or L-selectin. Overexpression of MUC1F on the surface of S2-013 cells blocked the interactions of E-selectin to tumor-associated ligand(s) but did not affect accessibility of monoclonal antibodies to other cell surface glycoproteins (CD9, CD44). Cell aggregation assays revealed that MUC1F expressed by S2-013 cells was able to bind to intracellular adhesion molecule-1 expressed on B cells. Overexpression of MUC1F containing a targeted mutation (the tandem repeat domain entirely or partially deleted) did not block the binding of E-selectin to its S2-013-associated ligand. These results demonstrate for the first time that the heavily O-glycosylated tandem repeat domain of MUC1 can simultaneously mediate and block binding to adhesion molecules with some molecular specificity and further support the hypothesis that MUC1 plays a dual role in the metastatic spread of tumor cells.


Subject(s)
Mucin-1/physiology , Neoplasms/pathology , Amino Acid Sequence , Cell Adhesion , E-Selectin/metabolism , Glycosylation , Humans , Molecular Sequence Data , Tandem Repeat Sequences , Tumor Cells, Cultured
9.
Am J Respir Crit Care Med ; 164(12): 2239-42, 2001 Dec 15.
Article in English | MEDLINE | ID: mdl-11751193

ABSTRACT

Idiopathic pulmonary fibrosis (IPF) is a chronic and often fatal disorder. Fibroplasia and deposition of extracellular matrix are dependent, in part, on angiogenesis and vascular remodeling. We obtained open lung biopsies from patients undergoing thoracic surgery for reasons other than interstitial lung disease (control) (n = 78) and from patients with IPF (n = 91). We found that levels of epithelial neutrophil-activating peptide 78 (ENA-78) were greater from tissue specimens of IPF patients, as compared with control subjects. When ENA-78 was depleted from IPF tissue specimens, tissue-derived angiogenic activity was markedly reduced. Immunolocalization of ENA-78 demonstrated that hyperplastic Type II pneumocytes and macrophages were the predominant cellular sources of ENA-78. These findings support the notion that ENA-78 may be an important additional factor that regulates angiogenic activity in IPF.


Subject(s)
Angiogenesis Inducing Agents/physiology , Chemokines, CXC , Interleukin-8/analogs & derivatives , Interleukin-8/physiology , Lung/blood supply , Neovascularization, Pathologic , Pulmonary Fibrosis/physiopathology , Angiogenesis Inducing Agents/metabolism , Animals , Chemokine CXCL5 , Cornea/blood supply , Enzyme-Linked Immunosorbent Assay , Epithelium/metabolism , Epithelium/pathology , Fibroblasts/pathology , Humans , Interleukin-8/metabolism , Lung/metabolism , Lung/pathology , Macrophages/metabolism , Macrophages/pathology , Neovascularization, Pathologic/physiopathology , Pulmonary Fibrosis/metabolism , Pulmonary Fibrosis/pathology , Rats , Rats, Long-Evans
10.
J Immunol ; 167(6): 3494-504, 2001 Sep 15.
Article in English | MEDLINE | ID: mdl-11544343

ABSTRACT

The use of chemokine antagonism as a strategy to inhibit leukocyte trafficking into inflammatory sites requires identification of the dominant chemokines mediating recruitment. The chemokine(s) directing T cells into cardiac allografts during acute rejection remain(s) unidentified. The role of the CXC chemokines IFN-gamma inducible protein 10 (IP-10) and monokine induced by IFN-gamma (Mig) in acute rejection of A/J (H-2(a)) cardiac grafts by C57BL/6 (H-2(b)) recipients was tested. Intra-allograft expression of Mig was observed at day 2 posttransplant and increased to the time of rejection at day 7 posttransplant. IP-10 mRNA and protein production were 2.5- to 8-fold lower than Mig. Whereas allografts were rejected at day 7-9 in control recipients, treatment with rabbit antiserum to Mig, but not to IP-10, prolonged allograft survival up to day 19 posttransplant. At day 7 posttransplant, allografts from Mig antiserum-treated recipients had marked reduction in T cell infiltration. At the time of rejection in Mig antiserum-treated recipients (i.e., days 17-19), intra-allograft expression of macrophage-inflammatory protein-1alpha, -1beta, and their ligand CCR5 was high, whereas expression of CXCR3, the Mig receptor, was virtually absent. Mig was produced by the allograft endothelium as well as by recipient allograft-infiltrating macrophages and neutrophils, indicating the synergistic interactions between innate and adaptive immune compartments during acute rejection. Collectively, these results indicate that Mig is a dominant recruiting factor for alloantigen-primed T cells into cardiac allografts during acute rejection. Although Mig antagonism delays acute heart allograft rejection, the results also suggest that the alloimmune response circumvents Mig antagonism through alternative mechanisms.


Subject(s)
Chemokines, CXC/physiology , Chemotaxis, Leukocyte/physiology , Graft Rejection/immunology , Heart Transplantation/immunology , Intercellular Signaling Peptides and Proteins , T-Lymphocyte Subsets/immunology , Acute Disease , Amino Acid Sequence , Animals , Chemokine CXCL10 , Chemokine CXCL9 , Endothelium, Vascular/metabolism , Gene Expression Profiling , Gene Expression Regulation , Graft Rejection/pathology , In Situ Hybridization , Isoantigens/immunology , Macrophages/metabolism , Male , Mice , Mice, Inbred A , Mice, Inbred C57BL , Molecular Sequence Data , Myocardium/immunology , Myocardium/metabolism , Myocardium/pathology , Neutrophils/metabolism , Postoperative Period , Receptors, CCR5/biosynthesis , Receptors, CCR5/genetics , Receptors, CXCR3 , Receptors, Chemokine/biosynthesis , Receptors, Chemokine/genetics , Transplantation, Heterotopic , Transplantation, Homologous/immunology
11.
J Clin Endocrinol Metab ; 86(8): 3968-74, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11502840

ABSTRACT

A patient with adrenocortical carcinoma presented with fever, leukocytosis, and increased acute phase reactants. The tumor was infiltrated with neutrophils. Immunohistochemical staining of the tumor showed positive signal for epithelial neutrophil-activating protein-78, an angiogenic and chemotactic CXC chemokine. Conditioned medium from tumor-derived cells (RL-251) showed high concentration of IL-8, epithelial neutrophil-activating protein-78, Gro alpha, and Gro gamma, angiogenic CXC chemokines with a potential role in tumorigenesis. An adrenal cancer/severe combined immunodeficiency mouse chimera was developed. Mice grew tumors rapidly, and circulating levels of IL-8 and epithelial neutrophil-activating protein-78 were detected. In contrast, animals transplanted with NCI-H295 cells, a nonchemokine-secreting cell line, grew tumors more slowly and did not have detectable chemokine levels. Similar to the patient, mice with RL-251 tumors developed marked leukocytosis and neutrophilia, and their tumors were infiltrated with neutrophils. Mice were passively immunized with epithelial neutrophil-activating protein-78 antisera. A marked decrease in tumor growth was observed. Potential for chemokine production by other adrenocortical tumors was investigated by RT-PCR in archival material. Six of seven adrenal carcinomas and one of three adenomas had cDNA for IL-8; six of seven carcinomas and the three adenomas had cDNA for epithelial neutrophil-activating protein-78. We concluded that the clinical presentation of this case resulted from increased tumor production of chemotactic chemokines. Through their angiogenic and chemotactic properties these chemokines may play an important role in adrenal tumorigenesis.


Subject(s)
Adrenal Cortex Neoplasms/genetics , Adrenal Cortex Neoplasms/immunology , Chemokines, CXC/genetics , Interleukin-8/genetics , 17-Hydroxycorticosteroids/urine , 17-Ketosteroids/urine , Adenoma/genetics , Adenoma/immunology , Adenoma/pathology , Adenoma/surgery , Adrenal Cortex Neoplasms/pathology , Adrenal Cortex Neoplasms/surgery , Adrenocorticotropic Hormone , Aged , Chemokine CXCL5 , Chemokines, CXC/analysis , Circadian Rhythm , Fever , Humans , Hydrocortisone/blood , Hydrocortisone/urine , Immunohistochemistry , Interleukin-8/analogs & derivatives , Interleukin-8/analysis , Leukocytosis , Male , Neutrophil Activation , Neutrophils/pathology , Reverse Transcriptase Polymerase Chain Reaction , Syndrome , Tumor Cells, Cultured
12.
J Clin Invest ; 108(4): 547-56, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11518728

ABSTRACT

Bronchiolitis obliterans syndrome (BOS) is the major limitation to survival after lung transplantation. Acute rejection, its main risk factor, is characterized by perivascular/bronchiolar leukocyte infiltration. BOS is characterized by persistent peribronchiolar leukocyte recruitment leading to airway fibrosis and obliteration. The specific mechanism(s) by which these leukocytes are recruited are unknown. Because MCP-1, acting through its receptor CCR2, is a potent mononuclear cell chemoattractant, we hypothesized that expression of this chemokine during an allogeneic-response promotes persistent recruitment of leukocytes and, ultimately, rejection. We found that elevated levels of biologically active MCP-1 in human bronchial lavage fluid (BALF) were associated with the continuum from acute to chronic allograft rejection. Translational studies in a murine model of BOS demonstrated increased MCP-1 expression paralleling mononuclear cell recruitment and CCR2 expression. Loss of MCP-1/CCR2 signaling, as seen in CCR2(-/-) mice or in WT mice treated with neutralizing antibodies to MCP-1, significantly reduced recruitment of mononuclear phagocytes following tracheal transplantation and led to attenuation of BOS. Lymphocyte infiltration was not reduced under these conditions. We suggest that MCP-1/CCR2 signaling plays an important role in recruitment of mononuclear phagocytes, a pivotal event in the pathogenesis of BOS.


Subject(s)
Bronchiolitis Obliterans/etiology , Chemokine CCL2/physiology , Chemotaxis, Leukocyte/physiology , Graft Rejection/etiology , Heart-Lung Transplantation , Lung Transplantation , Postoperative Complications/etiology , Animals , Bronchiolitis Obliterans/metabolism , Bronchoalveolar Lavage Fluid/chemistry , Chemokine CCL2/analysis , Chemokine CCL2/genetics , Chemokine CXCL2 , Chemokines/analysis , Chemokines/physiology , Cohort Studies , Female , Graft Rejection/metabolism , Humans , Immunophenotyping , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Middle Aged , Models, Animal , Phagocytosis , Postoperative Complications/metabolism , RNA, Messenger/biosynthesis , Receptors, CCR2 , Receptors, Chemokine/biosynthesis , Receptors, Chemokine/deficiency , Receptors, Chemokine/genetics , Receptors, Chemokine/physiology , Signal Transduction
13.
J Immunol ; 167(2): 623-7, 2001 Jul 15.
Article in English | MEDLINE | ID: mdl-11441062

ABSTRACT

Recent reports highlighted the chemotactic activities of antimicrobial peptide defensins whose structure, charge, and size resemble chemokines. By assaying representative members of the four known families of chemokines we explored the obverse: whether some chemokines exert antimicrobial activity. In a radial diffusion assay, only recombinant monokine induced by IFN-gamma (MIG/CXCL9), IFN-gamma-inducible protein of 10 kDa (IP-10/CXCL10), and IFN-inducible T cell alpha chemoattractant (I-TAC/CXCL11), members of the IFN-gamma-inducible tripeptide motif Glu-Leu-Arg (ELR)(-) CXC chemokines, were antimicrobial against Escherichia coli and Listeria monocytogenes. Similar to human defensins, antimicrobial activities of the chemokines were inhibited by 50 and 100 mM NaCl. The concentration of MIG/CXCL9 and IP-10/CXCL10 released from IFN-gamma-stimulated PBMC in 24 h were, respectively, 35- and 28-fold higher than from unstimulated cells. Additionally, the amounts of chemokines released per monocyte suggest that, in tissues with mononuclear cell infiltration, IFN-gamma-inducible chemokines may reach concentrations necessary for microbicidal activity. IFN-gamma-inducible chemokines may directly inactivate microbes before attracting other host defense cells to the area of infection.


Subject(s)
Anti-Bacterial Agents/immunology , Chemokines, CXC/immunology , Defensins/immunology , Intercellular Signaling Peptides and Proteins , Interferon-gamma/pharmacology , Peptide Fragments/immunology , Amino Acid Motifs , Arginine/metabolism , Chemokine CXCL9 , Chemokines, CXC/biosynthesis , Conserved Sequence , Defensins/biosynthesis , Escherichia coli/growth & development , Escherichia coli/immunology , Glutamic Acid/metabolism , Humans , Leucine/metabolism , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Listeria monocytogenes/growth & development , Listeria monocytogenes/immunology , Peptide Fragments/biosynthesis
14.
Glycobiology ; 11(6): 459-71, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11445551

ABSTRACT

The biochemical and biophysical properties of mucins are largely determined by extensive O-glycosylation of serine- and threonine-rich tandem repeat (TR) domains. In a number of human diseases aberrant O-glycosylation is associated with variations in the properties of the cell surface-associated and secreted mucins. To evaluate in vivo the O-glycosylation of mucin TR domains, we generated recombinant chimeric mucins with TR sequences from MUC2, MUC4, MUC5AC, or MUC5B, which were substituted for the native TRs of epitope-tagged MUC1 protein (MUC1F). These hybrid mucins were extensively O-glycosylated and showed the expected association with the cell surface and release into culture media. The presence of different TR domains within the chimeric mucins appears to have limited influence on their posttranslational processing. Alterations in glycosylation were detailed by fast atom bombardment mass spectrometry and reactivity with antibodies against particular blood-group and tumor-associated carbohydrate antigens. Future applications of these chimeras will include investigations of mucin posttranslational modification in the context of disease.


Subject(s)
Mucins/metabolism , Protein Processing, Post-Translational , Repetitive Sequences, Amino Acid , Amino Acid Sequence , Antigens, Tumor-Associated, Carbohydrate/biosynthesis , Blood Group Antigens , Carbohydrate Sequence , Glycosylation , Humans , Molecular Sequence Data , Mucin-1/metabolism , Mucins/genetics , Oligosaccharides/chemistry , Recombinant Fusion Proteins/metabolism , Spectrometry, Mass, Fast Atom Bombardment
16.
Am J Physiol Lung Cell Mol Physiol ; 281(1): L92-7, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11404251

ABSTRACT

Interleukin (IL)-12 is a potent inducer of interferon (IFN)-gamma. We postulated that IL-12 would attenuate bleomycin-induced pulmonary fibrosis. To test this hypothesis, we administered IL-12 or murine serum albumin to bleomycin-treated mice by daily intraperitoneal injection until day 12. Mice treated with IL-12 demonstrated decreased hydroxyproline levels compared with control treated mice. Furthermore, administration of IL-12 led to a time-dependent increase in both lung and bronchoalveolar lavage fluid IFN-gamma. The antifibrotic effect of IL-12 could be attenuated with simultaneous administration of neutralizing anti-IFN-gamma antibodies. These findings support the notion that IL-12 attenuates bleomycin-induced pulmonary fibrosis via modulation of IFN-gamma production.


Subject(s)
Interleukin-12/pharmacology , Pulmonary Fibrosis/prevention & control , Animals , Antibodies/pharmacology , Bleomycin , Bronchoalveolar Lavage Fluid/chemistry , Female , Hydroxyproline/metabolism , Interferon-gamma/immunology , Interferon-gamma/metabolism , Lung/drug effects , Lung/metabolism , Mice , Mice, Inbred CBA , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/metabolism
17.
Biochem Biophys Res Commun ; 284(1): 42-9, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11374868

ABSTRACT

This study provides functional evidence that glycosphingolipids constitute ligands for E-selectin but not P-selectin. Chinese hamster ovary (CHO) cells expressing E-selectin (CHO-E) or P-selectin (CHO-P) were perfused over alpha2,3-sialyl Lewis X (alpha2,3-sLe(x)) presented as the hexaosylceramide glycosphingolipid adsorbed in a monolayer containing phosphatidylcholine and cholesterol. CHO-E cells tethered extensively and formed slow, stable rolling interactions with alpha2,3-sLe(x) glycosphingolipid but not with the comparable alpha2,6-sLe(x) glycosphingolipid. Tethering/rolling varied with wall shear stress, selectin density, and ligand density. In contrast, alpha2,3-sLe(x) glycosphingolipid supported only limited, fast CHO-P cell rolling. As calculated from a stochastic model of cell rolling, the step size between successive bond releases from the alpha2,3-sLe(x) glycosphingolipid was smaller for CHO-E than CHO-P cells, whereas the opposite effect was observed for the waiting time between these events. Detachment assays revealed stronger adhesive interactions of CHO-E than CHO-P cells with alpha2,3-sLe(x) glycosphingolipid. These findings indicate that glycosphingolipids expressing an appropriate oligosaccharide mediate cell tethering/rolling via E-selectin but not P-selectin.


Subject(s)
Cell Movement/physiology , E-Selectin/metabolism , Glycosphingolipids/metabolism , Neutrophils/metabolism , Animals , CHO Cells , COS Cells , Cell Adhesion/drug effects , Cell Adhesion/physiology , Cell Extracts/pharmacology , Cell Line , Cell Movement/drug effects , Cricetinae , Dose-Response Relationship, Drug , E-Selectin/genetics , Epitopes/metabolism , Glycosphingolipids/pharmacology , Humans , Lewis X Antigen/metabolism , Ligands , Lipids/isolation & purification , Lipids/pharmacology , Models, Biological , Neutrophils/chemistry , Neutrophils/drug effects , P-Selectin/genetics , P-Selectin/metabolism , Stochastic Processes , Stress, Mechanical , Transfection
18.
Cancer Immunol Immunother ; 49(11): 587-92, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11225989

ABSTRACT

The recently described CC chemokine, 6C-kine, is unique in that it contains -six rather than the usual four conserved cysteines typical of this family. Furthermore, murine 6C-kine binds to one of the CXC chemokine receptors CXCR3, in addition to its other known receptor CCR7. We have shown that two other ligands of CXCR3, IP-10 and MIG, are potent inhibitors of tumor growth in severe combined immunodeficiency (SCID) mice. We postulated that murine 6C-kine may also inhibit tumor growth via inhibition of angiogenesis in this model. SCID mice (n = 6 per group) inoculated with A549 human lung cancer cells were treated with either 6C-kine (100 ng intra-tumor injection every other day) or control protein for 8 weeks. Tumors from murine 6C-kine-treated mice (288 +/- 26 mm3) were significantly smaller than tumors from control treated mice (788 +/- 156 mm3, P = 0.005). Additionally, murine 6C-kine reduced metastases compared with controls (0.5 +/- 0.3 vs 3.0 +/- 1.2 metastases per animal, P = 0.05). Tumor vascularity (as assessed by vessel density counting) was reduced in murine 6C-kine-treated mice compared with controls. Murine 6C-kine had no direct effect on proliferation of A549 cells, and there were no differences in the infiltration of leukocyte sub-populations, assessed by flow cytometry, in the treatment groups. Interestingly, human 6C-kine, unlike murine 6C-kine, does not bind CXCR3 and had no anti-tumor effect in the same model. These data suggest that murine 6Ckine has anti-tumor effects independent of its leukocyte-recruiting activity. Furthermore, while not confirmatory, these data lend further support to the fact that CXCR3 may be the receptor for angiostatic CXC chemokines.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Chemokines, CC/therapeutic use , Lung Neoplasms/drug therapy , Neoplasms, Experimental/drug therapy , Animals , Carcinoma, Non-Small-Cell Lung/pathology , Cell Division/drug effects , Chemokine CCL21 , Chimera , Female , Humans , Leukocytes/immunology , Lung Neoplasms/pathology , Mice , Mice, SCID , Neoplasm Metastasis , Neoplasms, Experimental/pathology , Neovascularization, Pathologic/drug therapy , Receptors, CXCR3 , Receptors, Chemokine/physiology , Tumor Cells, Cultured
19.
Arthritis Rheum ; 44(1): 31-40, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11212173

ABSTRACT

OBJECTIVE: Angiogenesis, the growth of new blood vessels, is vital to the ingress of inflammatory leukocytes in rheumatoid arthritis (RA) synovial tissue and to the growth and proliferation of RA pannus. The factors that mediate the growth of new blood vessels have not been completely defined. This study examined the ability of Glu-Leu-Arg (ELR)-containing chemokines to induce angiogenesis in the RA joint. METHODS: To reflect angiogenic activity in vivo, we selected a model using whole human synovial tissue rather than isolated cells. Tissues were examined by immunohistochemistry and enzyme-linked immunosorbent assay, and tissue homogenates were immunoneutralized and assayed for their ability to induce endothelial cell chemotaxis and rat corneal neovascularization. RESULTS: Cells expressing interleukin-8 (IL-8) and epithelial neutrophil activating peptide 78 (ENA-78) were located in proximity to factor VIII-related antigen-immunopositive endothelial cells. RA homogenates produced more IL-8 and ENA-78 compared with normal synovial tissue homogenates. Moreover, homogenates from RA synovial tissue produced significantly more chemotactic activity for endothelial cells in vitro and angiogenic activity in the rat cornea in vivo than did normal synovial tissue homogenates. The effects of IL-8 and ENA-78 accounted for a significant proportion of the chemotactic activity of endothelial cells and angiogenic activity found in RA synovial tissue homogenates. CONCLUSION: These results indicate that the ELR-containing chemokines IL-8 and ENA-78 are important contributors to the angiogenic activity found in the inflamed RA joint. It is possible that efforts aimed at down-regulating these chemokines offer a novel targeted therapy for the treatment of RA.


Subject(s)
Arthritis, Rheumatoid/physiopathology , Chemokines, CXC/pharmacology , Interleukin-8/analogs & derivatives , Interleukin-8/pharmacology , Neovascularization, Pathologic/drug therapy , Adult , Aged , Aged, 80 and over , Animals , Arthroplasty , Chemokine CXCL5 , Chemotaxis, Leukocyte/drug effects , Chemotaxis, Leukocyte/immunology , Endothelium, Vascular/cytology , Endothelium, Vascular/immunology , Female , Humans , Male , Middle Aged , Neutrophil Activation/drug effects , Neutrophil Activation/immunology , Synovial Membrane/drug effects
20.
Cancer Immunol Immunother ; 50(10): 533-8, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11776375

ABSTRACT

Tumor growth requires angiogenesis, which in turn requires an imbalance in the presence of angiogenic and angiostatic factors. We have shown that the CXC chemokine family, consisting of members that are either angiogenic or angiostatic, is a major determinant of tumor-derived angiogenesis in non-small-cell lung cancer (NSCLC). Intratumor injection of interferon-inducible protein 10 (IP-10, or CXCL10), an angiostatic CXC chemokine, led to reduced tumor growth in a SCID mouse model of NSCLC. In this study, we hypothesized that treatment with CXCL10 would, by restoring the angiostatic balance, improve long-term survival in NSCLC-bearing SCID mice. To test this hypothesis, A549 NSCLC cells were injected in the subcutis of the flank, followed by intratumor injections with CXCL10 continuously (group I), or for ten weeks (group II), or a control group (human serum albumin). Median survival was 169, 130, and 86 days respectively (P<0.0001). We extended these studies to examine the mechanism of prolonged survival in CXCL10-treated mice. CXCL10 treatment inhibited lung metastases, but was dependent upon continued treatment, and was associated with an increased rate of apoptosis in the primary tumor, with no direct effect on the proliferation of the NSCLC cells. Furthermore, the inhibition of lung metastases was due to the angiostatic effect of CXCL10 on the primary tumor, since the rate of apoptosis within lung metastases was unaffected. These data suggest that anti-angiogenic therapy of human lung cancer should be continued indefinitely to realize persistent benefit, and confirms the anti-metastatic capacity of localized angiostatic therapy.


Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Chemokines, CXC/administration & dosage , Lung Neoplasms/drug therapy , Neovascularization, Pathologic/drug therapy , Animals , Carcinoma, Non-Small-Cell Lung/blood supply , Carcinoma, Non-Small-Cell Lung/immunology , Chemokine CXCL10 , Chemokines, CXC/immunology , Female , Humans , Interferon-gamma/immunology , Lung Neoplasms/blood supply , Lung Neoplasms/immunology , Mice , Mice, SCID , Neovascularization, Pathologic/immunology , Survival Analysis , Tumor Cells, Cultured
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