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1.
Oncogene ; 35(15): 1909-18, 2016 Apr 14.
Article in English | MEDLINE | ID: mdl-26477313

ABSTRACT

The BRAF(V600E) mutation is found in approximately 40% of papillary thyroid cancers (PTC). Mice with thyroid-specific expression of Braf(V600E) (TPO-Braf(V600E)) develop PTC rapidly with high levels of serum thyroid-stimulating hormone (TSH). It is unclear to what extent the elevated TSH contributes to tumor progression. To investigate the progression of Braf(V600E)-induced PTC (BVE-PTC) under normal TSH, we transplanted BVE-PTC tumors subcutaneously into nude and TPO-Braf(WT) mice. Regression of the transplanted tumors was observed in both nude and TPO-Braf(WT) mice. They were surrounded by heavy lymphocyte infiltration and oncogene-induced senescence (OIS) was demonstrated by strong ß-gal staining and absence of Ki-67 expression. In contrast, BVE-PTC transplants continued to grow when transplanted into TPO-Braf(V600E) mice. The expression of Trp53 was increased in tumor transplants undergoing OIS. Trp53 inactivation reversed OIS and enabled tumor transplants to grow in nude mice with characteristic cell morphology of anaplastic thyroid cancer (ATC). PTC-to-ATC transformation was also observed in primary BVE-PTC tumors. ATC cells derived from Trp53 knockout tumors had increased PI3K/AKT signaling and became resistant to Braf(V600E) inhibitor PLX4720, which could be overcome by combined treatment of PI3K inhibitor LY294002 and PLX4720. In conclusion, BVE-PTC progression could be contained via p53-dependent OIS and TSH is a major disruptor of this balance. Simultaneous targeting of both MAPK and PI3K/AKT pathways offer a better therapeutic outcome against ATC. The current study reinforces the importance of rigorous control of serum TSH in PTC patients.


Subject(s)
Carcinoma, Papillary/pathology , Neoplasm Proteins/physiology , Thyroid Neoplasms/pathology , Thyrotropin/physiology , Tumor Suppressor Protein p53/biosynthesis , Animals , Carcinoma/genetics , Carcinoma/pathology , Carcinoma, Papillary/genetics , Cellular Senescence , Chromones/pharmacology , Chromones/therapeutic use , Disease Progression , Down-Regulation , Female , Gene Expression Regulation, Neoplastic , Genes, p53 , Humans , Indoles/pharmacology , Indoles/therapeutic use , Lymphocytes, Tumor-Infiltrating/immunology , MAP Kinase Signaling System/drug effects , Mice , Mice, Inbred BALB C , Mice, Knockout , Mice, Nude , Mice, Transgenic , Morpholines/pharmacology , Morpholines/therapeutic use , Mutation, Missense , Neoplasm Proteins/blood , Neoplasm Proteins/genetics , Neoplasm Transplantation , Phosphatidylinositol 3-Kinases/physiology , Phosphoinositide-3 Kinase Inhibitors , Proto-Oncogene Proteins B-raf/antagonists & inhibitors , Proto-Oncogene Proteins B-raf/genetics , Proto-Oncogene Proteins B-raf/physiology , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Proto-Oncogene Proteins c-akt/physiology , Signal Transduction/drug effects , Sulfonamides/pharmacology , Sulfonamides/therapeutic use , Thyroid Neoplasms/genetics , Thyrotropin/blood , Tumor Suppressor Protein p53/deficiency , Tumor Suppressor Protein p53/genetics
2.
Cancer Gene Ther ; 15(2): 101-7, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18197164

ABSTRACT

Anaplastic thyroid carcinoma is the most aggressive type of thyroid malignancies. Previously, we demonstrated that tumorigenicity of anaplastic thyroid carcinoma cell line ARO was significantly reduced following interleukin (IL)-12 gene transfer. We suspected that tumor target structure in ARO/IL-12 cells might be changed and such a change may make them more susceptible to be killed through mechanisms apart from natural killer-dependent pathway. To identify genes involved, we examined gene expression profile of ARO and ARO/IL-12 by microarray analysis of 3757 genes. The most highly expressed gene was cannabinoid receptor 2 (CB2), which was expressed eightfold higher in ARO/IL-12 cells than ARO cells. CB2 agonist JWH133 and mixed CB1/CB2 agonist WIN-55,212-2 could induce significantly higher rate of apoptosis in ARO/IL-12 than ARO cells. Similar results were obtained when ARO cells were transfected with CB2 transgene (ARO/CB2). A considerable regression of thyroid tumors generated by inoculation of ARO/CB2 cells was observed in nude mice following local administration of JWH133. We also demonstrated significant increase in the induction of apoptosis in ARO/IL12 and ARO/CB2 cells following incubation with 15 nM paclitaxel, indicating that tumor cells were sensitized to chemotherapy. These data suggest that CB2 overexpression may contribute to the regression of human anaplastic thyroid tumor in nude mice following IL-12 gene transfer. Given that cannabinoids have shown antitumor effects in many types of cancer models, CB2 may be a viable therapeutic target for the treatment of anaplastic thyroid carcinoma.


Subject(s)
Carcinoma/metabolism , Carcinoma/therapy , Genetic Therapy , Interleukin-12/physiology , Receptor, Cannabinoid, CB2/biosynthesis , Receptor, Cannabinoid, CB2/genetics , Thyroid Neoplasms/metabolism , Thyroid Neoplasms/therapy , Animals , Apoptosis/genetics , Cell Line, Tumor , Female , Gene Transfer Techniques , Humans , Interleukin-12/administration & dosage , Interleukin-12/genetics , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Transplantation , Receptor, Cannabinoid, CB2/metabolism , Receptor, Cannabinoid, CB2/physiology
3.
Appl Radiat Isot ; 64(7): 769-77, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16713896

ABSTRACT

A non-invasive imaging technique capable of relating a signal from the beta-cells to their mass will be of immense value in understanding the progression of diabetes. Several molecular markers have indeed been identified and investigations are ongoing aimed at accomplishing the said goal. These include pancreatic islet antigen (IC-2), somatostatin receptors (SSTRs), and sulfonylurea receptors (SURs) on the pancreatic beta-cells. Therefore investigations exploiting the potential application of the radiolabeled ligands for these receptors for beta-cell imaging are receiving intensive research attention. Radioiodinated peptidomimetic based on beta-naphthylalanine and n-hexanediamine has been synthesized. The molecule was subjected to in vitro and in vivo evaluation. Radioligand binding studies on CHO cell line expressing the SSTR2 showed very low affinity. Nonetheless, biodistribution in normal mice showed significant uptake in the pancreas. There was partial blockage of the pancreatic uptake when excess of the peptidomimetic was coinjected. The result implies that the pancreatic uptake was receptor mediated but may not involve the SSTR2 and therefore warrants further investigation.


Subject(s)
Insulin-Secreting Cells/diagnostic imaging , Iodine Radioisotopes/chemistry , Radiopharmaceuticals/chemical synthesis , beta-Alanine/analogs & derivatives , Animals , CHO Cells , Cricetinae , Insulin-Secreting Cells/metabolism , Isotope Labeling/methods , Magnetic Resonance Spectroscopy , Mass Spectrometry , Mice , Mice, Inbred CBA , Radionuclide Imaging , Tissue Distribution , beta-Alanine/chemistry , beta-Alanine/metabolism
4.
J Leukoc Biol ; 78(1): 51-61, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15809289

ABSTRACT

The role of innate immune cells in the recognition and activation of xenogeneic endothelium has always been considered secondary to the initial insult of xenoreactive natural antibodies (XNA) and complement. It was argued, however, that innate immune cells are capable of recognizing and activating xenogeneic endothelium in the absence XNA and complement. Here, we show that porcine aortic endothelial cells (PAECs) activate human neutrophils directly. This contact-dependent activation causes a transient calcium rise leading to increased reactive oxygen metabolite (ROM) production. Neutrophil gene-expression profiling using an adenylate uridylate-rich element-based microarray revealed a dramatic change in the neutrophil gene profiles upon exposure to PAECs. The PAEC-dependent neutrophil transcriptional activity was further confirmed by real-time polymerase chain reaction, which revealed a rapid increase in the mRNA message of a number of inflammatory cytokines. The activation of human neutrophils by PAECs was independent of galactose alpha1,3-galactose (Galalpha1,3-gal) structures, as inclusion of saturating concentrations of anti-Galalpha1,3-gal l antibodies had no significant effect. Furthermore, this activation was inhibited in the presence of the calcium chelator 1,2-bis(O-aminophenyl-ethane-ethane)-N,N,N',N'-tetraacetic acid-acetoxymethyl ester and the ROM inhibitor diphelylene iodonium. Our data illustrate the direct activation of innate immune cells by PAECs in the absence of XNA and complement and suggest alternative recognition sites between PAECs and human innate immune cells.


Subject(s)
Endothelial Cells/immunology , Gene Expression Profiling , Gene Expression Regulation/immunology , Graft Rejection/immunology , Neutrophils/immunology , Transplantation, Heterologous/immunology , Animals , Antigens, Surface/chemistry , Antigens, Surface/immunology , Aorta/cytology , Aorta/immunology , Calcium Signaling/immunology , Cells, Cultured , Chelating Agents/pharmacology , Chemotaxis, Leukocyte/immunology , Cytokines/genetics , Disaccharides/immunology , Enzyme Inhibitors/pharmacology , Humans , Oligonucleotide Array Sequence Analysis , RNA, Messenger/metabolism , Reactive Oxygen Species/antagonists & inhibitors , Reactive Oxygen Species/metabolism , Sus scrofa , Transcriptional Activation/immunology
5.
J Dent Res ; 84(5): 414-7, 2005 May.
Article in English | MEDLINE | ID: mdl-15840775

ABSTRACT

Papillon-Lefèvre syndrome (PLS), palmoplantar hyperkeratosis with periodontitis, has been genetically characterized. However, suspected associated immune dysfunctions remain elusive. The purpose of this study was to evaluate peripheral blood lymphocyte levels and natural killer (NK) cell cytotoxicity in PLS. Twenty patients and 20 healthy controls were examined. Peripheral blood lymphocytes were analyzed by flow cytometry for surface markers. NK cell cytotoxicity against K562 cells was determined by means of a 51Cr release assay. White blood cell differential and proportions of B-, T-, T-helper, T-suppressor, and NK cells revealed only sporadic borderline variations from control values. In contrast, NK cell cytotoxicity was consistently and severely depressed (32-53% of control values) in all patients. To the best of our knowledge, this newly described impairment of NK cell cytotoxic function is the first consistent immune dysfunction reported in PLS. This suggests that the impaired NK cell cytotoxicity might contribute to the pathogenesis of PLS-associated periodontitis.


Subject(s)
Cytotoxicity, Immunologic/immunology , Papillon-Lefevre Disease/immunology , Adolescent , Adult , B-Lymphocytes/immunology , Child , Child, Preschool , Chromium Radioisotopes , Female , Flow Cytometry , Humans , K562 Cells , Killer Cells, Natural/immunology , Leukocyte Count , Lymphocyte Count , Male , Periodontitis/immunology , Radiopharmaceuticals , T-Lymphocytes/immunology , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Regulatory/immunology
6.
Appl Radiat Isot ; 62(1): 39-47, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15498683

ABSTRACT

Numerous molecular entities with diverse structures have been radiolabeled and investigated as potential infection and inflammation detection agents. However, none of these molecules have gained the acceptance of gallium citrate or radiolabeled autologous white blood cells. We have radioiodinated interleukin-8 using two different methods and tested the biological behavior of the products in mice. As expected, the direct radioiodinated material displayed extensive in vivo deiodination. The use of pyridine-based prosthetic label yielded a product with better kinetics than the direct radioiodination method and showed a better target to non-target ratio. Nonetheless, this method is not suited for labeling of bioactive peptides such as the title peptide because of the very high specific activity required to prevent cytotoxic effects in a human application.


Subject(s)
Escherichia coli Infections/diagnostic imaging , Escherichia coli Infections/metabolism , Interleukin-8/pharmacokinetics , Neutrophils/diagnostic imaging , Neutrophils/metabolism , Animals , Cells, Cultured , Interleukin-8/chemistry , Iodine Radioisotopes/chemistry , Iodine Radioisotopes/pharmacokinetics , Isotope Labeling/methods , Metabolic Clearance Rate , Mice , Mice, Inbred CBA , Organ Specificity , Radionuclide Imaging , Radiopharmaceuticals/chemical synthesis , Radiopharmaceuticals/pharmacokinetics , Tissue Distribution
7.
J Leukoc Biol ; 76(3): 603-8, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15178700

ABSTRACT

Recruitment of leukocytes from bloodstream to extrahematic sites is tightly regulated by a variety of adhesion molecules that are expressed on the leukocytes and the vessel walls. In this manuscript, we describe the interactions between natural killer (NK) cells and activated, autologous platelets under physiologic flow. We found that surface-adherent human platelets are capable of recruiting human NK cells from flow and that this recruitment is characterized by an initial tethering followed by a rolling phase. Both phases were dependent on the adhesion molecule P-selectin and its counter-ligand on the NK cells (P-selectin glycoprotein ligand 1). Activation of rolling NK cells with inflammatory mediators commonly found in atherosclerotic plaques (interleukin-12 and leukotriene B4) causes immediate cessation of the rolling process and conversion to stationary adhesion. Blocking antibodies to the adhesion molecules membrane-activated complex-1 and leukocyte function antigen-1 inhibited this conversion. Our data suggest that platelets deposited at sites of vascular injury may provide an alternative substrate to endothelial cells for initial recruitment of NK cells to the vessel wall. This may result in extravasation of the NK cells if the appropriate chemotactic signal is applied. These data implicate the P-selectin and integrin family of adhesion molecules in the recruitment of NK cells to atherosclerotic sites.


Subject(s)
Blood Platelets/immunology , Cell Adhesion/immunology , Chemotaxis, Leukocyte/immunology , Inflammation Mediators/pharmacology , Interleukin-12/pharmacology , Killer Cells, Natural/immunology , P-Selectin/immunology , Antibodies/pharmacology , Blood Platelets/metabolism , CD18 Antigens/immunology , Cells, Cultured , Humans , Inflammation Mediators/immunology , Interleukin-12/immunology , Killer Cells, Natural/drug effects , Leukotriene B4/immunology , Leukotriene B4/pharmacology , Lymphocyte Function-Associated Antigen-1/immunology , Macrophage-1 Antigen/immunology
8.
Appl Radiat Isot ; 60(6): 839-43, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15110348

ABSTRACT

We have synthesized 2-[(18)F]-fluoroisonicotinic acid hydrazide by nucleophilic displacement reaction on ethyl-2- (trimethylammonium)-isonicotinate precursor in acetonitrile. Kryptofix 222 was used as the phase transfer catalyst. The intermediate fluorinated ethyl ester reacted with hydrazine hydrate to produce the hydrazide. Excellent radiochemical yield was attained with total synthesis time of approximately 60 min. Biological evaluation was performed in bacterial cells and biodistribution in normal as well as E. coli infected CBA/J mice. It was found that the S. pneumoniae cells retained the radiotracer in an in vitro assay. The tracer showed positive localization at the infection/inflammation site in E. coli infected mice.


Subject(s)
Escherichia coli Infections/diagnostic imaging , Fluorine Radioisotopes , Infections/diagnostic imaging , Tuberculosis, Pulmonary/diagnostic imaging , Animals , Disease Models, Animal , Humans , Hydrazines/chemical synthesis , Isonicotinic Acids/chemical synthesis , Mice , Mice, Inbred BALB C , Radionuclide Imaging
9.
Allergy ; 57(6): 508-18, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12028116

ABSTRACT

BACKGROUND: Date fruit and pollen antigens share a number of cross-reactive epitopes. Date pollen has been shown to cross-react with antigens from Artemisia, cultivated rye (Secale cereale), Timothy grass (Phleum pratense), Sydney golden wattle (Acacia longifolia) and Bermuda grass (Cynodon dactylon) pollen. The present study was carried out to examine any cross-reactivities between date palm polypeptides and antigens of some common foods and vegetables that have been implicated in the oral allergy syndrome (OAS). Because most of such cross-reactivities in other allergens are attributable to the presence of carbohydrate chains and profilin, their role was also investigated. METHODS: Fresh extracts of 20 common fruits and vegetables were prepared. Putative date profilins were isolated by affinity chromatography using a poly L-proline column. Date fruit extracts were digested by various endoglycosidases and the immunoglobulin (Ig)E binding of the postdigest products was assessed in immunoblots. Rabbit antisera to whole date fruit extracts, Timothy grass profilin and putative date profilins, as well as human sera from date sensitive individuals were used in immunoblotting, ELISA and in inhibition experiments. RESULTS: IgG, ELISA and immunoblot results with the different rabbit antisera and date-sensitive atopic sera showed several antigenic cross-reactivities and similar cross-reactivities were seen with birch, date and timothy grass profilins. IgE, ELISA and immunoblot experiments with pooled date sensitive human sera showed a range of cross-reactivities with some food extracts. A number of the IgE cross-reactivities could be inhibited after preabsorption of pooled sera with date extracts. Sixty-six percent of individual date hypersensitive human sera bound IgE in putative date fruit profilin and their pooled sera bound IgE in birch pollen profilin. IgE-binding of the endoglycosidase digested date fruit extracts to atopic serum pool was restricted to only a very low molecular weight band of 6.5-8 kDa. CONCLUSION: These results indicate that date palm polypeptides share cross-reactive IgG and IgE epitopes with a number of foods implicated in the oral allergy syndrome, bind to birch and Timothy grass profilins and bind IgE through glycosyl residues. The clinical relevance of these cross-reactivities needs to be further elucidated.


Subject(s)
Contractile Proteins , Cross Reactions/immunology , Food Hypersensitivity/etiology , Fruit/adverse effects , Fruit/immunology , Peptides/adverse effects , Peptides/immunology , Allergens/administration & dosage , Allergens/adverse effects , Allergens/immunology , Animals , Dose-Response Relationship, Immunologic , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Epitopes/immunology , Galectin 3/blood , Galectin 3/drug effects , Galectin 3/immunology , Glycosylation/drug effects , Humans , Immunoblotting , Immunoglobulin E/blood , Immunoglobulin E/immunology , Immunoglobulin G/blood , Immunoglobulin G/immunology , Microfilament Proteins/adverse effects , Microfilament Proteins/immunology , Microfilament Proteins/isolation & purification , Molecular Weight , Peptides/administration & dosage , Pollen/adverse effects , Pollen/immunology , Profilins , Proline/adverse effects , Proline/immunology , Proline/isolation & purification , Rabbits , Syndrome
10.
Xenotransplantation ; 8(3): 172-5, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11472624

ABSTRACT

Higher primates, including humans, have high levels of pre-existing naturally circulating antibodies that predominantly recognize the epitope Gal (1,3-Gal), which is highly expressed on the surface of xenogenic cells. Deposition of these antibodies on the endothelial cell surface of vascularized xenografts leads to an activation of the classical pathway of the complement system, resulting in tissue ischemia and necrosis with rapid demise of the xenograft. This hyperacute rejection (HAR) is always a major barrier in xenograft transplantation and should be minimized by accurately monitoring the naturally occurring antibodies. In the present study, we utilized a simple and rapid flow cytometric (FCM) assay to monitor the presence of these naturally occurring antibodies. We found that the FCM assay is very effective in measuring human antibodies bound to the xenogenic cells, which cause cytotoxicity. This assay could be useful in the pre- and post-xenotransplantation monitoring of xenoantibodies, thus, helping in the development of strategies to block the binding of preformed human antibodies to the xenograft in order to overcome the problem of HAR.


Subject(s)
Antibodies, Heterophile/blood , Cell Survival , Endothelium, Vascular/cytology , Adult , Animals , Aorta , Cells, Cultured , Disaccharides/immunology , Epitopes/immunology , Flow Cytometry/methods , Humans , Middle Aged , Swine
11.
Transplantation ; 71(6): 796-801, 2001 Mar 27.
Article in English | MEDLINE | ID: mdl-11330545

ABSTRACT

BACKGROUND: Vaccinia virus complement control protein (VCP) was the first secretory microbial protein shown to have structural similarity to the family of complement control proteins. VCP can block both the classical and alternate complement pathways. Recently, VCP has been shown to bind to heparin, and this property contributes to separate functions, making the molecule a multifunctional protein. METHODS: VCP prepared from a natural infection of RK-13 cells with vaccinia virus was purified to homogeneity. Cultured pig aortic endothelial cells (PAECs) were mixed with human serum, anti-Gal alpha1,3 Gal antibody, neutrophils, or natural killer (NK) cells in the presence or absence of VCP and either direct binding of FITC-labeled antibody or killing by cytotoxic cells was estimated. RESULTS: Our cell culture studies demonstrate that VCP blocks complement-mediated killing of PAECs by human serum in a dose-dependent manner. We also demonstrate that VCP is capable of blocking Gal alpha1,3 Gal binding sites on PAECS. Surprisingly, VCP effectively blocked interactions between PAECs and cytotoxic cells such as human naive neutrophils and NK cells. CONCLUSION: VCP is a novel protein amongst the complement control protein family and can, not only block xenorejection by inhibiting complement but also by blocking killing by cytotoxic cells.


Subject(s)
Endothelium, Vascular/cytology , T-Lymphocytes, Cytotoxic/immunology , Viral Proteins/pharmacology , Animals , Antibody-Dependent Cell Cytotoxicity/drug effects , Aorta/cytology , Cytotoxicity, Immunologic , Graft Rejection/prevention & control , Humans , Swine , Transplantation, Heterologous/immunology
12.
Nucl Med Biol ; 28(3): 225-33, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11323231

ABSTRACT

The success of (111)In-pentetreotide as a cancer-imaging agent has given impetus to the search for other peptide-based radiopharmaceuticals. The labeling with Tc-99m has become even more attractive because of the ready availability and near ideal physical properties. Additionally, the kinetics of the peptide-receptor interactions favors the radiolabeling with technetium-99m. A somatostatin analog RC-160 has been labeled with Tc-99m using the "3+1" mixed ligand approach utilizing the NNS/S coordination sites. The ternary complex was formed in greater than 95% within 30 min by simultaneous reduction and complexation of technetium-99m pertechnetate. The Tc-99m and the surrogate rhenium complexes showed similar chromatographic behavior. The complex was evaluated by in vitro receptor binding studies carried out on HTB-121 breast cancer cell line and biodistribution studies performed in normal mice. Our findings suggest that RC-160 can be labeled by the mixed ligand approach with the complex retaining its biological activity and warrants further studies.


Subject(s)
Radiopharmaceuticals/chemical synthesis , Somatostatin/chemical synthesis , Animals , Breast Neoplasms/metabolism , Female , Humans , Ligands , Mice , Radioligand Assay , Somatostatin/analogs & derivatives , Somatostatin/pharmacokinetics , Technetium Compounds/chemistry , Tissue Distribution , Tumor Cells, Cultured/metabolism
13.
Biochem Pharmacol ; 61(5): 517-25, 2001 Mar 01.
Article in English | MEDLINE | ID: mdl-11239494

ABSTRACT

Fluorinated analogues of propranolol, namely trifluoroethyl propranolol (F3), pentafluoropropyl propranolol (F5), and heptafluorobutyl propranolol (F7), were found to induce reactive oxygen metabolite (ROM) production in human neutrophils in a dose-dependent manner. Preincubation of neutrophils with the calcium chelator BAPTA-AM or the tyrosine kinase inhibitor genistein inhibited this ROM production. Direct measurements of intracellular calcium revealed that these analogues caused a transient increase in intracellular calcium. In addition, these fluorinated analogues of propranolol caused a transient increase in actin polymerization. The effects of these compounds were found to be dependent upon the degree of fluorination of the parent compound. Propranolol, on the other hand, had no direct effect on ROM, calcium, or actin polymerization when added alone to neutrophils, although it did modify responses of cells to various stimuli. Whereas ROM production induced by the chemotactic peptide formyl-methionyl-leucyl-phenylalanine was enhanced in a dose-dependent manner, the response to the particulate stimulus, latex beads, was abolished.


Subject(s)
Calcium/metabolism , Neutrophils/drug effects , Propranolol/pharmacology , Reactive Oxygen Species/metabolism , Actins/metabolism , Fluorine/chemistry , Homeostasis/drug effects , Humans , In Vitro Techniques , Neutrophils/metabolism , Oxidants/chemistry , Oxidants/pharmacology , Propranolol/analogs & derivatives , Propranolol/chemistry
14.
Int Arch Allergy Immunol ; 123(2): 137-44, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11060485

ABSTRACT

BACKGROUND: Date fruits are allergenic and standardized extracts are required for diagnosis and therapy of this allergy. Since there are several cultivars of dates, this study was carried out to assess the allergenicity of different cultivars in order to select suitable source material for standardization. METHODS: The protein profiles of 18 of the most commonly sold varieties were compared by SDS-PAGE and their relative allergenicity assessed by SPT and IgE-based ELISA and immunoblotting. Thirty-two date fruit-sensitive patients were skin tested with a pooled extract from all the cultivars. Six of the patients with high SPT results (> or =3+) who volunteered were further tested with the 18 cultivars and their sera used in ELISA and immunoblotting. RESULTS: Six of the cultivars gave high SPT-positive reactions in > or =4 of patients. Five of these high SPT-reactive cultivars gave high IgE ELISA scores (> or =0.58) but individual cultivars varied in their number of IgE immunoblot bands. Cultivar-specific IgE-binding patterns indicated that only certain cultivars bound IgE at molecular weights of < or =14.3 and 27-33 kDa whilst all cultivars bound to a 54-58 kDa doublet. Cultivars that bind to the < or =14.3 and 27-33 kDa bands appeared to form the majority of the high SPT-reactive cultivars. When individual sera of 24 of the 32 SPT-positive patients were used in IgE immunoblots with the pooled cultivar extract, all sera bound IgE at < or =14.3 and 27-33 kDa and about 60% of sera bound to a 54-58 kDa doublet bands. CONCLUSIONS: These results indicate that allergenicity of date fruits is a cultivar-specific phenomenon. Sixty to 100% of sera from date fruit-allergic patients bind IgE to three major allergens of < or =14.3, 27-33 and 54-58 kDa. Five of the cultivars that evoke high SPT reactions, high IgE ELISA scores and bind IgE to the major allergens, can be selected for the preparation of 'in-house' allergen extracts and for allergen standardization.


Subject(s)
Allergens/analysis , Epitopes/immunology , Food Hypersensitivity/etiology , Fruit/adverse effects , Immunoglobulin E/immunology , Adult , Allergens/chemistry , Allergens/immunology , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Female , Food Hypersensitivity/blood , Food Hypersensitivity/epidemiology , Fruit/immunology , Humans , Immunoblotting , Immunoglobulin E/blood , Male , Molecular Weight , Plant Extracts/analysis , Plant Extracts/immunology , Saudi Arabia/epidemiology , Skin Tests
15.
Transplantation ; 70(6): 917-28, 2000 Sep 27.
Article in English | MEDLINE | ID: mdl-11014645

ABSTRACT

BACKGROUND: Interaction between vascularized xenograft and host immune system is thought to occur via Galactose alpha (1,3) Galactose (Gala 1,3 gal) structures decorating the xenograft. METHODS: We raised anti-Gala 1,3 gal-BSA polyclonal antibodies in baboons and investigated effect(s) of these antibodies as well as soluble Gala 1,3 gal-BSA on human naive natural killer (NK) cell interactions with porcine aortic endothelial cells. RESULTS: We demonstrate that human naive (unstimulated) NK cells recognize xenogeneic endothelial cells under conditions where binding to the Gala 1,3 gal structures is minimized by the presence of blocking anti-Gala 1,3 gal IgG or soluble Gala 1-3 gal and in the absence of xenoreactive natural antibodies and complement. After xenogeneic encounter both endothelial cells and human NK cells are activated. Endothelial cell activation is rapid and is manifested initially by an intraendothelial calcium transient and subsequently by expression of P-selectin and vascular endothelial cell adhesion molecule-1 on the xenoendothelium surface. NK cell activation is manifested by increased expression of perforin and increased cytotoxicity towards the xenoendothelium. Neither recognition nor activation of the xenoendothelium was affected by the introduction of either anti-Gala 1,3 gal IgG or soluble Gala 1-3 gal. CONCLUSION: Our data provide evidence that innate immune cells, such as NK cells, recognize and activate xenoendothelial cells independently of Gala 1-3 gal structures and raise the possibility of novel interactive sites on both human naive NK cells and discordant xenogeneic endothelium.


Subject(s)
Endothelium, Vascular/cytology , Galactose/pharmacology , Killer Cells, Natural/cytology , Killer Cells, Natural/transplantation , Transplantation, Heterologous/pathology , Animals , Antibodies/blood , Calcium/metabolism , Cell Transplantation , Galactose/immunology , Humans , Lymphocyte Activation/drug effects , Papio , Sheep , Swine
16.
Br J Cancer ; 79(7-8): 1234-9, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10098765

ABSTRACT

Tumour cell invasion and metastasis is a multistep process that involves the degradation of extracellular matrix proteins by matrix metalloproteinases (MMPs). Tissue inhibitors of metalloproteinases (TIMPs) act as negative regulators of MMPs and thus prevent tumour cell invasion and metastasis by preserving extracellular matrix (ECM) integrity. In the present study we examined the expression of one member of TIMPs, TIMP-1, in 39 thyroid tumour specimens and two thyroid carcinoma cell lines (NPA and SW579). We also investigated the effect of high TIMP-1 expression on the invasive potential of NPA cells. Northern blot analysis showed that TIMP-1 mRNA levels correlated directly with tumour aggressiveness: the highest number of TIMP-1 transcripts was found in stages III and IV vs benign goitre (P < 0.0001). However, TIMP-1 expression was not increased in NPA and SW579 cells, both of which are derived from poorly differentiated thyroid tumours. Immunohistochemical study showed strong TIMP-1 staining in the stroma cells of advanced stages of carcinomas. Overexpression of TIMP-1 by gene transfer resulted in a significant suppression of the malignant phenotype of NPA cells as judged by an in vitro tumour invasion assay. These results suggest that high levels of TIMP-1 transcripts in advanced stages of thyroid carcinoma likely come from stroma rather than thyroid cancer cells, and TIMP-1 may function as a thyroid tumour invasion/metastasis suppressor.


Subject(s)
Carcinoma, Papillary/metabolism , Neoplasm Proteins/metabolism , RNA, Messenger/metabolism , Thyroid Neoplasms/metabolism , Tissue Inhibitor of Metalloproteinase-1/metabolism , Adult , Aged , Carcinoma/metabolism , Carcinoma/pathology , Carcinoma, Papillary/pathology , Female , Gene Expression Regulation, Enzymologic , Gene Expression Regulation, Neoplastic , Genetic Vectors/administration & dosage , Goiter, Nodular/metabolism , Humans , Male , Middle Aged , Neoplasm Invasiveness , Neoplasm Proteins/genetics , Neoplasm Staging , Thyroid Neoplasms/pathology , Tissue Inhibitor of Metalloproteinase-1/genetics , Transfection
17.
Allergy ; 54(12): 1270-7, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10688430

ABSTRACT

BACKGROUND: Date-palm (Phoenix dactylifera L.) fruits are eaten daily by most inhabitants of the Middle East and the neighboring countries. Recent reports have indicated that dates are allergenic. This study aimed to investigate the antigenic and allergenic potential of date fruits. METHODS: Date-fruit extracts from eight cultivars were evaluated in skin prick tests (SPT) in an atopic population, used to produce antisera, analyzed by SDS-PAGE, and fractionated by gel-filtration chromatography. Sera from SPT-positive individuals were evaluated by ELISA and RAST, and in anti-igE immunoblot experiments. RESULTS: About 13% of patients were SPT-positive for at least two extracts. SDS-PAGE of whole extracts revealed 15-18 protein bands of 6.5->100 kDa, and Sephacryl S-200 fractions gave distinct peptide bands. RAST and anti-IgE ELISA gave a range of positive results, which could be abrogated when sera were preabsorbed with fruit extracts. IgE immunoblots of different extracts with pooled positive sera revealed different anti-IgE-binding immunoprints. All the positive sera from fruit-allergic and pollen-allergic individuals bound strongly to two anti-IgE reactive bands of 6.5 to 12-14 kDa and 28-33 kDa, respectively, and about 50% of sera bound to a 54-58-kDa band. CONCLUSIONS: These results strongly indicate that 1) date-palm fruit is a potent allergen 2) sera from fruit-allergic as well as pollen-allergic patients recognize common fruit-specific epitopes 3) there is heterogeneity in patient responses to the different extracts.


Subject(s)
Allergens/adverse effects , Antigens/adverse effects , Food Hypersensitivity , Fruit/adverse effects , Allergens/chemistry , Allergens/immunology , Antigens/chemistry , Antigens/immunology , Blotting, Western , Chromatography, Gel , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Fruit/chemistry , Fruit/immunology , Humans , Immunoglobulin E/blood , Plant Extracts/adverse effects , Plant Extracts/chemistry , Plant Extracts/immunology , Radioallergosorbent Test , Skin Tests
18.
J Immunol ; 161(7): 3737-45, 1998 Oct 01.
Article in English | MEDLINE | ID: mdl-9759899

ABSTRACT

The cytokine IL-12 is proposed to play a bridging role between innate and adaptive immunity. Here we demonstrate that IL-12 binds specifically to human neutrophils. This binding leads to a transient increase in 1) intracellular free calcium due to its release from membrane-enclosed stores and its influx from extracellular medium, 2) actin polymerization, and 3) tyrosine phosphorylation. IL-12 treatment also leads to a concentration-dependent increase in reactive oxygen metabolite production. The effect of IL-12 is blocked by neutralizing Abs to IL-12. Inhibition of either calcium transient or tyrosine phosphorylation causes inhibition of reactive oxygen metabolite production. However, inhibition of actin polymerization enhances IL-12-induced oxidase activation. Our data suggest 1) a direct role for IL-12 in the activation of human neutrophils, and 2) a calcium-dependent signaling pathway for IL-12.


Subject(s)
Calcium/metabolism , Interleukin-12/physiology , Neutrophils/metabolism , Signal Transduction/immunology , Tyrosine/metabolism , Actins/metabolism , Calcium/physiology , Humans , Interleukin-12/metabolism , Neutrophil Activation/drug effects , Neutrophils/drug effects , Neutrophils/immunology , Phosphorylation/drug effects , Polymers/metabolism , Protein Binding/immunology , Signal Transduction/drug effects , Tyrosine/physiology
19.
Am J Reprod Immunol ; 40(1): 13-8, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9689355

ABSTRACT

PROBLEM: Cytokines have been shown to be present in human follicular fluid and have regulatory functions on follicular maturation. The presence of leukemia inhibitory factor (LIF) and interleukin (IL)-12 in human follicular fluid obtained at different stages of maturation was investigated. METHOD OF STUDY: Follicular fluids and granulosa cells were obtained from preovulatory and immature follicles. Follicular fluids from both groups were assayed for IL-12 and LIF by enzyme-linked immunosorbent assay. Granulosa cells from preovulatory and immature follicles were treated with human chorionic gonadotropin (hCG) in vitro and subsequent LIF and IL-12 production were measured. RESULTS: The average concentration of LIF was significantly higher in preovulatory follicles (7.6 +/- 1.3 pg/ml, n = 24) than in immature follicles (2.0 +/- 1.3 pg/ml, n = 6). The concentration of IL-12 was significantly higher in follicular fluid obtained from immature follicles (10.9 +/- 5.0 pg/ml) than in preovulatory follicles (1.3 +/- 0.4 pg/ml). hCG only stimulated LIF production from mature granulosa cells; it had no effect on IL-12 production. CONCLUSIONS: IL-12 and LIF are present in follicular fluid and their levels are regulated differently during follicular maturation. hCG stimulates LIF production from granulosa cells in vitro.


Subject(s)
Follicular Fluid/metabolism , Growth Inhibitors/biosynthesis , Interleukin-2/biosynthesis , Interleukin-6 , Lymphokines/biosynthesis , Cells, Cultured , Chorionic Gonadotropin/pharmacology , Female , Fertilization in Vitro , Granulosa Cells/metabolism , Growth Inhibitors/analysis , Humans , Infertility, Female/therapy , Leukemia Inhibitory Factor , Lymphokines/analysis , Ovarian Follicle/metabolism , Pregnancy
20.
Allergy ; 53(3): 255-65, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9542605

ABSTRACT

Aeroallergens and antigens in sandstorm dust, extracts of which were skin prick test (SPT) positive in allergic patients, were detected by rocket immunoelectrophoresis and ELISA. Fungi and bacteria isolated by agar settle plates and soil dilution and soil washing methods were enumerated and identified. Cat dander, Acacia, Alternaria, Aspergillus, Chenopodium, Cladosporium, Bermuda grass, Pithecellobium, Prosopis, Rumex, cultivated rye, and Washingtonia palm allergens were detected by both methods. Viable microbes including 1892 +/- 325 colony-forming units (cfu) of bacteria, and 869 +/- 75 cfu of fungi were isolated per gram of dust by the soil dilution method. Randomly selected microbial colonies on streaking and subculture were found to consist of between two and seven mixed colonies. Fungi including Alternaria, Aspergillus, Botrytis, Cladosporium, Mortierella, Mucor, Mycelia sterilia, Penicillium, Pythium, Ulocladium, Verticillium, and some yeasts were isolated. Actinomyces, Bacillus, Pseudomonas, and mostly coagulase-negative Staphylococcus species were identified, but the bulk of unidentified bacterial isolates were mainly mixed colonies of rods, cocci, coccobacilli, and some filamentous types. Six-hour agar settle-plate counts during sandstorms were 100 and 40% higher for bacteria and fungi, respectively, than without sandstorms. The most abundant aeroallergens were those of Acacia, Alternaria, Aspergillus, Bermuda grass, Cladosporium, cultivated rye, Prosopis, and cat dander. Pithecellobium dulce, Rumex crispus, and Washingtonia palm allergens were detectable for the first time in Riyadh. IgE reactivities of the dust in man were demonstrated by ELISA using sera from atopic, exposed, and normal subjects. These results indicate that sandstorm dust is a prolific source of potential triggers of allergic and nonallergic respiratory ailments, and the methods mentioned here should be routinely used for quick sampling of the environment.


Subject(s)
Air Pollutants/analysis , Allergens/analysis , Bacteria/isolation & purification , Dust , Fungi/isolation & purification , Respiratory Hypersensitivity/etiology , Respiratory Tract Diseases/etiology , Wind , Enzyme-Linked Immunosorbent Assay , Humans , Immunoelectrophoresis , Saudi Arabia , Skin Tests
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