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1.
J Appl Microbiol ; 124(3): 867-873, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29280544

ABSTRACT

AIMS: The purpose of this survey was to estimate the respective prevalence of the 'gang of seven' and 'non-gang of seven' serotypes of Shigatoxigenic and enteropathogenic Escherichia coli and to identify the O80:H2 serotype in 245 intestinal contents collected at two slaughterhouses in Belgium in 2014. METHODS AND RESULTS: After overnight enrichment growth, the 69 intestinal contents testing positive with PCR targeting the eae, stx1 and stx2 genes were inoculated onto four agar media. Of the 2542 colonies picked up, 677 from 59 samples were PCR confirmed. The most frequent virulotypes were eae+ in 47 (80%) samples, stx2+ in 20 (34%) samples and eae+ stx1+ in 16 (27%) samples. PCR-positive colonies belonged to different virulotypes in 36 samples. No colony was O80-positive, whereas two eae+ colonies from two samples were O26:H11, 50 eae+ stx1+ and eae+ from eight samples were O103:H2 and two eae+ stx1+ stx2+ colonies from one sample were O157:H7. CONCLUSIONS: The 'non-gang of seven' serotypes are more frequent than the 'gang of seven' serotypes and the O80:H2 serotype was not detected among Shigatoxigenic and enteropathogenic Escherichia coli in the intestines of cattle at these two slaughterhouses. SIGNIFICANCE AND IMPACT OF THE STUDY: Although the identification protocols of Shigatoxigenic Escherichia coli focus on the 'gang of seven' serotypes, several other serotypes can be present with possible importance in public health. Innovative selective identification procedures should be designed.


Subject(s)
Enteropathogenic Escherichia coli/isolation & purification , Gastrointestinal Contents/microbiology , Shiga-Toxigenic Escherichia coli/isolation & purification , Abattoirs , Animals , Belgium , Cattle , Enteropathogenic Escherichia coli/genetics , Enteropathogenic Escherichia coli/metabolism , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Gastrointestinal Microbiome , Polymerase Chain Reaction , Prevalence , Serogroup , Serotyping , Shiga-Toxigenic Escherichia coli/genetics , Shiga-Toxigenic Escherichia coli/metabolism
3.
Mucosal Immunol ; 6(6): 1131-42, 2013 Nov.
Article in English | MEDLINE | ID: mdl-23462911

ABSTRACT

Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK), a TNF superfamily member, induces damage of the epithelial cells (ECs) and production of inflammatory mediaters through its receptor Fn14 in a model of acute colitis. In our current study of chronic colitis induced by repeated rectal injection of a hapten, we found that inflammation, fibrosis, and T helper 2 (Th2)-type immunity were significantly reduced in Fn14 gene knockout (KO) mice when compared with wild-type (WT) control mice. Expression of thymic stromal lymphopoietin (TSLP) was lower in Fn14 KO colon ECs than in WT ECs. TWEAK potentiates the induction of TSLP by interleukin-13 (IL-13) in colon explants from WT but not in Fn14 KO tissue. TSLP receptor KO mice exhibit milder chronic colitis, similar to that in Fn14 KO mice. TWEAK and IL-13 synergistically promote fibroblast proliferation. Thus we propose an IL-13-TWEAK/Fn14-TSLP axis as a key mechanism underlying chronic colitis with fibrosis.


Subject(s)
Colitis/immunology , Colon/pathology , Fibroblasts/immunology , Interleukin-13/metabolism , Receptors, Tumor Necrosis Factor/metabolism , Th2 Cells/immunology , Tumor Necrosis Factors/metabolism , Animals , Cell Proliferation , Cells, Cultured , Chronic Disease , Colitis/chemically induced , Cytokine TWEAK , Disease Models, Animal , Female , Fibrosis , Humans , Immunoglobulins/genetics , Immunoglobulins/metabolism , Interleukin-13/immunology , Mice , Mice, Inbred BALB C , Mice, Knockout , Organ Culture Techniques , Receptors, Cytokine/genetics , Receptors, Cytokine/metabolism , Receptors, Tumor Necrosis Factor/genetics , Receptors, Tumor Necrosis Factor/immunology , TWEAK Receptor , Trinitrobenzenesulfonic Acid/administration & dosage , Tumor Necrosis Factors/immunology
4.
J Viral Hepat ; 18(10): e550-60, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21914076

ABSTRACT

The present study was designed to determine the predictive factors for the viral response to pegylated interferon-alpha plus ribavirin combination therapy (PEGIFN/RBV) administered after curative treatment for hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC). The study group was 78 patients treated between January 2005 and January 2009. The sustained viral response (SVR) rate was 25.8% (15/58) in patients infected with HCV-genotype 1 and 55.0% (11/20) in those with genotype 2. Among the 78 patients, 32 (41.0%) could not complete the treatment protocol, and this was because of HCC recurrence in 17 (53%) of them. Multivariate analysis identified partial early viral response (pEVR) as the only independent determinant of SVR [odds ratio (OR) 14.73, P = 0.013] for patients with genotype 1. Multivariate analysis identified male gender (OR 8.72, P = 0.001) and interleukin-28B (IL-28B) genotype (rs8099917) TT (OR 7.93, P = 0.007) as independent predictors of pEVR. Multivariate analysis also identified IL-28B genotype GG+TG (OR 14.1, P = 0.021) and α-fetoprotein >30 (OR 5.4, P = 0.031) as independent predictors of null response. Patients with SVR showed a better survival rate than those without SVR (P = 0.034). The second HCC recurrence rate tended to be lower in patients with SVR than in those without SVR (P = 0.054). With regard to the prognosis of patients with SVR, it is desirable to achieve SVR with interferon therapy even when administered after HCC treatment. IL-28B genotype is a potentially useful marker for the response to PEGIFN/RBV therapy administered after curative treatment of HCV-related HCC.


Subject(s)
Antiviral Agents/administration & dosage , Carcinoma, Hepatocellular/drug therapy , Hepatitis C/drug therapy , Interferons/administration & dosage , Interleukins/genetics , Polymorphism, Genetic , Ribavirin/administration & dosage , Aged , Aged, 80 and over , Female , Genotype , Hepacivirus/classification , Hepacivirus/genetics , Hepatitis C/complications , Humans , Male , Middle Aged , Recurrence , Survival Analysis , Treatment Outcome
6.
Science ; 295(5564): 2433-5, 2002 Mar 29.
Article in English | MEDLINE | ID: mdl-11923534

ABSTRACT

Plastic deformation of materials occurs by the motion of defects known as dislocations and disclinations. High-resolution transmission electron microscopy was used to directly reveal the individual dislocations that constitute partial disclination dipoles in nanocrystalline, body-centered cubic iron that had undergone severe plastic deformation by mechanical milling. The mechanisms by which the formation and migration of such partial disclination dipoles during deformation allow crystalline solids to fragment and rotate at the nanometer level are described. Such rearrangements are important basic phenomena that occur during material deformation, and hence, they may be critical in the formation of nanocrystalline metals by mechanical milling and other deformation processes.

7.
Immunology ; 102(3): 289-300, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11298827

ABSTRACT

The interleukin-5 receptor alpha chain (IL-5Ralpha) is known to regulate the development and function of B cells and eosinophils. Although the functions of IL-5Ralpha cytoplasmic domain subregions have been studied extensively using cultured cell lines, this approach has limitations when studying the functions of distinct primary B-cell subpopulations and their responsiveness to IL-5. In the present study, we generated mice on an IL-5Ralpha null background, each expressing a mutant form of an IL-5Ralpha transgene ligated to a mu enhancer and VH promoter, either lacking the cytoplasmic DC3 region or substituting two proline residues for alanine (ApvA) in the membrane-proximal ppvp motif of the cytoplasmic domain. The ppvp motif, which mediates activation of JAK2/STAT5 and Btk, also contributes to c-fos, c-jun and c-myc expression. IL-5Ralpha null mutant mice showed impaired B-1-cell development, reduced serum immunoglobulin G3 (IgG3) and IgM, no IL-5-induced enhancement of B-cell proliferation and IL-5-induced switch recombination from the mu gene to gamma1 gene; these were not recovered following the expression of the ApvA mutant. In contrast, absence of the DC3 region affected the IL-5-induced switch recombination from the mu to the gamma1 gene and B-1-cell development, while IL-5-induced proliferation and IgM production were at levels similar to those of B cells expressing wild-type IL-5Ralpha transgene. The results clearly indicated that the ppvp motif and the DC3 region of IL-5Ralpha played distinct roles in B-cell proliferation and differentiation. Thus, this present approach offers new insights into the functions of the cytoplasmic subregions of IL-5Ralpha, in particular its carboxy-terminal region.


Subject(s)
B-Lymphocyte Subsets/immunology , Immunoglobulin Class Switching/immunology , Immunoglobulin G/biosynthesis , Receptors, Interleukin/immunology , Amino Acid Sequence , Animals , Cell Culture Techniques , Cell Differentiation/immunology , Cell Division/immunology , Cytoplasm/immunology , Immunoglobulin M/biosynthesis , Interleukin-5/immunology , Mice , Mice, Inbred C57BL , Mice, Transgenic , Molecular Sequence Data , Mutation , Receptors, Interleukin/genetics , Receptors, Interleukin-5 , Structure-Activity Relationship
8.
Int Immunol ; 13(4): 485-93, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11282988

ABSTRACT

Formation of the pre-BCR complex is a critical check point during B cell development and induces the transition of pro-B to pre-B cells. CD79b (Igbeta) is a signaling component in the pre-BCR complex, since differentiation to the pre-B phenotype is induced by cross-linking the CD79b expressed on developmentally arrested pro-B cells from recombination-activating gene (RAG)-2-deficient mice. Bruton's tyrosine kinase (BTK) plays important roles in B cell development. However, its molecular mechanisms in early B cell development are not fully understood. To examine whether BTK functions in CD79b-mediated signaling for the pro-B/pre-B transition, we utilized RAG2/BTK double-knockout (DKO) mice. Pro-B cells from RAG2/BTK-DKO mice did not differentiate into pre-B cells following CD79b cross-linking, although tyrosine phosphorylation of cellular proteins including Erk1/2 and phospholipase C-gamma2 was induced in the same manner as RAG2-KO mice. BTK is phosphorylated after cross-linking of CD79b on RAG2-deficient pro-B cells. These findings suggest that BTK-dependent pathways downstream of CD79b are critical for the pro-B/pre-B transition and BTK-independent signaling pathways are also activated via the pre-BCR complex.


Subject(s)
Antigens, CD/immunology , B-Lymphocytes/immunology , Cell Differentiation , Protein-Tyrosine Kinases/physiology , Signal Transduction , Agammaglobulinaemia Tyrosine Kinase , Animals , B-Lymphocytes/cytology , B-Lymphocytes/enzymology , CD79 Antigens , DNA-Binding Proteins , Isoenzymes/metabolism , Mice , Mice, Knockout , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3 , Mitogen-Activated Protein Kinases/metabolism , Phospholipase C gamma , Phosphorylation , Protein-Tyrosine Kinases/genetics , Receptors, Antigen, B-Cell/immunology , Type C Phospholipases/metabolism , Tyrosine/metabolism
9.
J Biol Chem ; 276(21): 18082-9, 2001 May 25.
Article in English | MEDLINE | ID: mdl-11278409

ABSTRACT

The lck gene encodes a protein-tyrosine kinase that plays a key role in signaling mediated through T cell receptor (TCR) and pre-TCR complexes. Transcription of the lck gene is regulated by two independent promoter elements: the proximal and distal promoters. Previous studies employing transgenic mice demonstrated that the sequence between -584 and -240 from the transcription start site in the mouse lck proximal promoter is required for its tissue-specific expression in the thymus. In this study, we demonstrate that a Krüppel-like zinc finger protein, mtbeta (BFCOL1, BERF-1, ZBP-89, ZNF148), previously cloned as a protein that binds to the CD3delta gene enhancer, binds to the -365 to -328 region of the lck proximal promoter. mtbeta is ubiquitously expressed in various cell lines and mouse tissues. Overexpressed mtbeta is more active in T-lineage cells than B-lineage cells for transactivating an artificial promoter consisting of the mtbeta binding site and a TATA box. Activity of the lck proximal promoter was significantly impaired by mutating the mtbeta binding site or by reducing mtbeta protein expression level by using antisense mRNA. Our results indicate that mtbeta activity is regulated in a tissue-specific manner and that mtbeta is a critical transactivator for the lck proximal promoter.


Subject(s)
Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/genetics , Animals , Cell Line , Humans , Promoter Regions, Genetic/genetics , T-Lymphocytes , Transcription, Genetic
10.
J Comput Assist Tomogr ; 24(6): 890-2, 2000.
Article in English | MEDLINE | ID: mdl-11105707

ABSTRACT

We present a case in which MR arteriography (MRA) with an indwelling catheter was used in a perfusion study of intrahepatic arterial chemotherapy for liver metastases. After embolization of collateral vessels using platinum coils, CT imaging was disturbed by strong artifact. However, platinum coils produced no MR artifact. In addition, MRA had greater advantages in depicting perfusion defects than perfusion scintigraphy. We consider MRA useful in assessing perfusion abnormalities during intrahepatic arterial chemotherapy.


Subject(s)
Antineoplastic Agents/therapeutic use , Catheters, Indwelling , Hepatic Artery , Liver Neoplasms/secondary , Magnetic Resonance Angiography , Antineoplastic Agents/administration & dosage , Artifacts , Collateral Circulation , Contrast Media , Embolization, Therapeutic/instrumentation , Gadolinium DTPA , Hepatic Artery/pathology , Humans , Infusions, Intra-Arterial , Liver Circulation , Liver Neoplasms/blood supply , Liver Neoplasms/drug therapy , Male , Middle Aged , Platinum , Tomography, X-Ray Computed
11.
Immunity ; 13(5): 599-609, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11114373

ABSTRACT

Lnk is an SH2 domain-containing adaptor protein expressed preferentially in lymphocytes. To illuminate the importance of Lnk, we generated lnk(-/-) mice. Whereas T cell development was unaffected, pre-B and immature B cells accumulated in the spleens. In the bone marrow, B-lineage cells were proportionately increased, reflecting enhanced production of pro-B cells that resulted in part from hypersensitivity of precursors to SCF, the ligand for c-kit. Hence, Lnk ordinarily acts to regulate B cell production. Further characterization of lnk(-/-) mice also revealed that full-length Lnk is a 68 kDa protein containing a conserved proline-rich region and a PH domain. Lnk is a representative of a multigene adaptor protein family whose members act, by analogy with Lnk, to modulate intracellular signaling.


Subject(s)
B-Lymphocytes/physiology , Proteins/physiology , Adaptor Proteins, Signal Transducing , Amino Acid Sequence , Animals , B-Lymphocytes/cytology , Cell Differentiation/physiology , Gene Expression Regulation, Developmental/immunology , Intracellular Signaling Peptides and Proteins , Membrane Proteins , Mice , Mice, Knockout , Molecular Sequence Data , Sequence Alignment , Signal Transduction , src Homology Domains
12.
Appl Radiat Isot ; 52(5): 1209-15, 2000 May.
Article in English | MEDLINE | ID: mdl-10836432

ABSTRACT

The right strategy for finding a new ESR dosimetric material sensitive to radiation is to follow the orthodox procedures used in the development of thermoluminescence dosimeters (TLD) and phosphorescence studies. Modern procedures used in materials sciences, such as computer calculation of molecular orbitals (MO), should be employed to estimate the ESR and optical properties of prospective materials. Radiation effects in lithium and magnesium sulfates and metal salts of organic acids, such as lithium and magnesium lactates, have been investigated in search for tissue-equivalent dosimeter with a large G value.

13.
Biochem Biophys Res Commun ; 272(1): 45-54, 2000 May 27.
Article in English | MEDLINE | ID: mdl-10872802

ABSTRACT

Engagement of cell-surface receptors leads to activation of protein tyrosine kinases, which in turn phosphorylate various downstream enzymes and adaptor proteins. Lnk is an adaptor protein that appears to be involved in signal transduction in lymphocytes, and forms an adaptor protein family with SH2-B. We tried to identify another member of the adaptor protein family and isolated the mouse APS (adaptor molecule containing PH and SH2 domains). APS contains a proline-rich region, PH and SH2 domains, and a putative tyrosine phosphorylation site at the C-terminal, and the overall structure resembles those of Lnk and SH2-B. APS is expressed in brain, kidney, muscle, and mature B cells in spleen. Mouse APS gene consists of 8 coding exons and is deduced to map to chromosome 5. APS is tyrosine phosphorylated at the C-terminal phosphorylation site conserved among the Lnk family adaptor proteins by stimulation of IL-5 or IL-3 as well as by crosslinking of B cell receptor complex. These results suggest that APS is a member of the Lnk family adaptor protein and likely plays a role in signaling in B cells.


Subject(s)
Adaptor Proteins, Signal Transducing , Proteins/genetics , Amino Acid Sequence , Animals , Base Sequence , Binding Sites , Blood Proteins/genetics , Cell Line , Chromosome Mapping , Cloning, Molecular , DNA Primers/genetics , Exons , Intracellular Signaling Peptides and Proteins , Membrane Proteins , Mice , Molecular Sequence Data , Phosphoproteins/genetics , Phosphorylation , Proteins/chemistry , RNA, Messenger/genetics , RNA, Messenger/metabolism , Sequence Deletion , Tissue Distribution , Tyrosine/chemistry , src Homology Domains/genetics
14.
Genes Cells ; 4(6): 353-62, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10421844

ABSTRACT

BACKGROUND: TRAF6, a member of the tumour necrosis factor receptor-associated factor family, was first identified as a transducer of CD40 and interleukin-1 receptor (IL-1R) signals based on the interaction of TRAF6 with the cytoplasmic tail of CD40 and with the IL-1R associated kinase in vitro. However, the functions of TRAF6 in vivo remain unidentified. RESULTS: We show that TRAF6-/- mice exhibit severe osteopetrosis and are defective in osteoclast formation. In vitro culture experiments revealed that osteoclast precursor cells derived from TRAF6-/- mice are unable to differentiate to functional osteoclasts in response to osteoclast differentiation factor (ODF). In bone marrow of TRAF6-/- mice, the number of sIgM+B220+ immature B cells is markedly reduced while the ratio of proB to preB cells is not affected. In contrast, development of thymocytes is not affected. Furthermore, TRAF6-/- mice are defective in lymph node organogenesis and IL-1 signalling in thymocytes. CONCLUSIONS: The results identify TRAF6 as an essential component of ODF signalling pathway, and also show that TRAF6 plays pivotal roles in immune and inflammatory systems in vivo.


Subject(s)
Interleukin-1/metabolism , Lymph Nodes/embryology , Osteopetrosis/genetics , Proteins/genetics , Signal Transduction/genetics , Animals , Bone Marrow Cells/cytology , Cell Differentiation , Embryonic and Fetal Development , Mice , Mice, Knockout , Osteoclasts/cytology , Proteins/metabolism , Receptors, Tumor Necrosis Factor/metabolism , Spleen/cytology , TNF Receptor-Associated Factor 6
15.
Acta Neurochir (Wien) ; 141(3): 315-9, 1999.
Article in English | MEDLINE | ID: mdl-10214489

ABSTRACT

The co-existence of multiple cerebral arteriovenous malformations (AVMs) and a spinal AVM is extremely rare. A 22-year-old man suddenly developed severe headache. Computed tomography (CT) scan showed intracerebral haemorrhage in the left occipital lobe. Cerebral angiography revealed eight AVMs; four were in the right frontal lobe and two each were in the right temporal and left occipital lobe, respectively. A huge high-flow spinal AVM was found incidentally. He had no other vascular lesions such as hereditary haemorrhagic telangiectasia. A left occipital craniotomy was performed and the ruptured left occipital AVMs were removed. Further therapeutic treatment was refused. To our knowledge, except for one autopsy case, this is the first reported patient with multiple cerebral AVMs with a spinal AVM. We discuss the characteristics of this case and review reported cases with cerebral and spinal AVMs.


Subject(s)
Cerebral Arteries/abnormalities , Cerebral Cortex/blood supply , Cerebral Veins/abnormalities , Intracranial Arteriovenous Malformations , Spinal Cord/blood supply , Adult , Arteriovenous Malformations/diagnostic imaging , Arteriovenous Malformations/pathology , Cerebral Cortex/diagnostic imaging , Cerebral Cortex/pathology , Humans , Intracranial Arteriovenous Malformations/diagnostic imaging , Intracranial Arteriovenous Malformations/pathology , Male , Radiography , Spinal Cord/diagnostic imaging , Spinal Cord/pathology
16.
Gan To Kagaku Ryoho ; 25(9): 1330-2, 1998 Jul.
Article in Japanese | MEDLINE | ID: mdl-9703820

ABSTRACT

Epirubicin and 5-FU were administered through an indwelling catheter inserted into the internal mammary artery and/or subclavian artery employing an implantable infusion port system for the treatment of unresectable advanced breast cancer and recurrent breast cancer. Intraarterial infusion chemotherapy proved to be an effective treatment modality for unresectable advanced breast cancer and recurrent breast cancer.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Neoplasm Recurrence, Local/drug therapy , Catheters, Indwelling , Doxorubicin/administration & dosage , Drug Administration Schedule , Epirubicin/administration & dosage , Female , Fluorouracil/administration & dosage , Humans , Infusions, Intra-Arterial/methods
17.
J Biol Chem ; 272(23): 14562-70, 1997 Jun 06.
Article in English | MEDLINE | ID: mdl-9169414

ABSTRACT

Stimulation of the T cell antigen receptor (TCR) activates a set of non-receptor protein tyrosine kinases that assist in delivering signals to the cell interior. Among the presumed substrates for these kinases, adaptor proteins, which juxtapose effector enzyme systems with the antigen receptor complex, figure prominently. Previous studies suggested that Lnk, a 38-kDa protein consisting of a single SH2 domain and a region containing potential tyrosine phosphorylation sites, might serve to join Grb2, phospholipase C-gamma1, and phosphatidylinositol 3-kinase to the TCR. To elucidate the physiological roles of Lnk in T cell signal transduction, we isolated the mouse Lnk cDNA, characterized the structure of the mouse Lnk gene, and generated transgenic mice that overproduce Lnk in thymocytes. Here we report that although Lnk becomes phosphorylated during T cell activation, it plays no limiting role in the TCR signaling process. Moreover, we have distinguished p38(Lnk) from the more prominent 36-kDa tyrosine phosphoproteins that appear in activated T cells. Together these studies suggest that Lnk participates in signaling from receptors other than antigen receptors in lymphocytes.


Subject(s)
Adaptor Proteins, Signal Transducing , Protein Biosynthesis , T-Lymphocytes/immunology , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , Exons , Flow Cytometry , GRB2 Adaptor Protein , Genomic Library , Intracellular Signaling Peptides and Proteins , Isoenzymes/metabolism , Membrane Proteins , Mice , Mice, Transgenic , Molecular Sequence Data , Molecular Weight , Phosphatidylinositol 3-Kinases , Phospholipase C gamma , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Polymerase Chain Reaction , Proteins/chemistry , Proteins/genetics , Proteins/metabolism , RNA, Messenger/biosynthesis , Receptors, Antigen, T-Cell/physiology , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/chemistry , Sequence Alignment , Sequence Homology, Amino Acid , Signal Transduction , Spleen/immunology , T-Lymphocyte Subsets/immunology , Thymus Gland/immunology , Transcription, Genetic , Type C Phospholipases/metabolism , src Homology Domains
18.
Annu Rev Immunol ; 15: 125-54, 1997.
Article in English | MEDLINE | ID: mdl-9143684

ABSTRACT

Studies performed during the past several years make plain that ligand occupancy of antigen receptors need not necessarily provoke identical responses in all instances. For example, ligation of antigen receptors may stimulate a proliferative response, induce a state of unresponsiveness to subsequent stimulation (anergy), or induce apoptosis. How does a single type of transmembrane receptor induce these very heterogeneous cellular responses? In the following pages, we outline evidence supporting the view that the nature of the ligand/receptor interaction directs the physical recruitment of signaling pathways differentially inside the lymphocyte and hence defines the nature of the subsequent immune response. We begin by providing a functional categorization of antigen receptor components, considering the ways in which these components interact with the known set of signal transduction pathways, and then review the evidence suggesting that differential signaling through the TCR is achieved by qualitative differences in the effector pathways recruited by TCR, perhaps reflecting the time required to bring complicated signal transduction elements into proximity within the cell. The time-constant of the interaction between antigen and receptor in this way determines, at least in part, the nature of the resulting response. Finally, although our review focuses substantially on T cell receptor signaling, we have included a less detailed description of B cell receptor signaling as well, simply to emphasize the parallels that exist in these two closely related systems.


Subject(s)
Receptors, Antigen, T-Cell/physiology , Animals , Calcium/metabolism , GTP-Binding Proteins/metabolism , Humans , Isoenzymes/metabolism , Lymphocyte Activation , Phospholipase C gamma , Phosphoric Monoester Hydrolases/metabolism , Protein Kinases/metabolism , Receptors, Antigen, B-Cell/physiology , Signal Transduction , T-Lymphocytes/immunology , T-Lymphocytes/physiology , Type C Phospholipases/metabolism
19.
Gan To Kagaku Ryoho ; 23(11): 1526-8, 1996 Sep.
Article in Japanese | MEDLINE | ID: mdl-8854797

ABSTRACT

In order to reduce toxic effects while attaining maximal therapeutic effects, epirubicin 10 mg/day, cyclophosphamide 100 mg/day and prednisolone 10 mg/day were administered through in indwelling catheter inserted into the internal mammary artery and/or subclavian artery for 3-4 weeks, employing the implantable port system for the treatment of unresectable breast cancer and recurrent cancer. Ten out of 11 patients (91%) with unresectable breast cancer showed a response (CR 3, PR 7, NC 1) to this modality of intra-arterial infusion chemotherapy. Seven out of 11 patients (64%) with recurrent cancer of the breast showed a response (CR 1, PR 6, NC 4). Intraarterial infusion chemotherapy for the unresectable advanced breast cancer and recurrent breast cancer proved to be an effective modality of treatment.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Infusion Pumps, Implantable , Cyclophosphamide/administration & dosage , Epirubicin/administration & dosage , Female , Fluorouracil/administration & dosage , Humans , Infusions, Intra-Arterial , Neoplasm Recurrence, Local/drug therapy , Prednisolone/administration & dosage
20.
Int Immunol ; 8(6): 951-60, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8671684

ABSTRACT

We have examined phosphorylation mediated by cross-talk between growth signal pathways induced by IL-2 and IL-5. To analyze the phosphorylation process in the same cells, we established two sublines, T88-Mbeta1, which is a subline of a murine IL-5-dependent cell line, T88-M, by introduction of the human IL-2 receptor beta chain (IL-2Rbeta), and secondly CTLL-5Ralphabeta, which is a subline of a murine IL-2-dependent cell line, CTLL-2, by introduction of the murine IL-5 receptor alpha chain (IL-5Ralpha) and IL-5 receptor beta chain (IL-5Rbeta, betac) genes. Both T88-Mbeta1 and CTLL-5Ralphabeta expressed high-affinity receptors for IL-2 and IL-5, and proliferated in response to both factors. Tyrosine phosphorylation of IL-2Rbeta was induced by stimulation of T88-Mbeta1 with not only IL-2 but also IL-5. Anti-IL-2Rbeta-directed immune complexes from T88-Mbeta1 stimulated with IL-5 as well as with IL-2 contained an activated tyrosine kinase. However, stimulation with IL-5 but not IL-2 induced the tyrosine phosphorylation of IL-5Rbeta, betac, suggesting that IL-2 does not activate a tyrosine kinase which efficiently catalyzes the IL-5Rbeta molecule in response to IL-5. On the other hand, the detection of JAK1 and the other common set of phosphotyrosine-containing proteins after stimulation with either IL-5 or IL-2 suggests the existence of the same tyrosine phosphorylation pathways.


Subject(s)
Interleukin-2/pharmacology , Interleukin-5/pharmacology , Proto-Oncogene Proteins , Receptors, Interleukin-2/metabolism , Receptors, Interleukin/metabolism , Animals , Cell Division/immunology , Cell Line , Janus Kinase 1 , Janus Kinase 2 , Janus Kinase 3 , Kinetics , Mice , Phosphorylation/drug effects , Protein-Tyrosine Kinases/analysis , Protein-Tyrosine Kinases/metabolism , Receptors, Interleukin/biosynthesis , Receptors, Interleukin-2/biosynthesis , Receptors, Interleukin-5 , T-Lymphocytes, Cytotoxic/enzymology
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