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1.
Int J Immunopathol Pharmacol ; 28(1): 114-8, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25816413

ABSTRACT

Transcutaneous electrical nerve stimulation (TENS) is extensively used as pain relief through endorphins release. Moreover, recent findings showed a role in the activation of the autonomic nervous system (ANS); it was evidenced by modification in the heart rate variability and ANS-related marker. The objective of this pilot study is to evaluate salivary alpha amylase (sAA) as a marker of stress in two groups of healthy subjects, one receiving ultra-low frequency transcutaneous electrical nerve stimulation (ULF-TENS) and one without stimulation. Sixty healthy people were enrolled. The test group consisted of 30 participants (15 men, 15 women). The control group consisted of 30 participants (15 men, 15 women). Statistical analysis showed that sAA levels were statistically different between men and women independently from TENS; we hypothesize that treatment could influence sAA levels because it is thought to activate µ opioid receptors. The results of this study seem to indicate that the analysis of sAA, through a non-invasive saliva sample, could be an efficient aid for understanding the functions of the autonomic nervous system.


Subject(s)
Biomarkers/metabolism , Saliva/metabolism , Adult , Autonomic Nervous System/metabolism , Female , Heart Rate/physiology , Humans , Male , Pilot Projects , Receptors, Opioid, mu/metabolism , Transcutaneous Electric Nerve Stimulation/methods , Young Adult
2.
J Ultrasound ; 16(4): 201-7, 2013 Oct 19.
Article in English | MEDLINE | ID: mdl-24432175

ABSTRACT

PURPOSE: To assess the impact of ultrasonography on defining the diagnostic and therapeutic pathways for pediatric patients admitted to the emergency department for acute abdominal pain. METHODS: We performed a retrospective study of all patients aged <16 years with acute abdominal pain who underwent ultrasound examination at our Diagnostic Imaging Department from October 2010 to March 2012. We investigated for each patient the pathway following ultrasound examination and definitive diagnosis. The impact of ultrasonography was defined based on the frequency with which the information resulting from this examination confirmed or denied the diagnostic suspicion made by the emergency physician on the basis of clinical and laboratory findings. RESULTS: In 497/729 patients (69 %), ultrasound examination did not determine variations in the diagnostic and therapeutic pathways, either because it confirmed the outcome of clinical examination and laboratory tests, or because, even addressing in the opposite direction to these, the emergency physician did not consider its result because of being particularly alarmed or sufficiently reassured by clinical examination and laboratory tests. In the remaining 232/729 cases (31 %), ultrasound examination determined an increase or a reduction of the provided care and attention (subsequently proved justified in the vast majority of cases) in spite of what was initially assessed based on clinical examination and laboratory tests. CONCLUSIONS: The results of our retrospective study demonstrated that ultrasonography was a valuable tool in the management of pediatric patients with acute abdominal pain together with clinical examination and laboratory tests.

3.
Ann Ital Chir ; 75(4): 495-8, 2004.
Article in Italian | MEDLINE | ID: mdl-15754704

ABSTRACT

The authors are surgeons of Moscati Hospital in Aversa (CE)-Italy, and one of them is a Radiologist in the same hospital; they describe a rare case of lumbar hernia, the Petits hernia and describe the anatomical aspects of parietals hernias. Subsequently they describe the diagnostics aspects and then the surgicals treatments. In this case-report the authors describe the surgical operation to use one prolene-net to close the parietal breach. The most important aspect, that the authors emphsasize, is the absolute importance of careful clinic examination to diagnose it. This work is completed with some pictures that show it; some pictures are made in operatory-room during the surgical treatment and some of them are TC images.


Subject(s)
Hernia, Abdominal , Diagnosis, Differential , Follow-Up Studies , Hernia, Abdominal/diagnosis , Hernia, Abdominal/diagnostic imaging , Hernia, Abdominal/surgery , Humans , Male , Middle Aged , Polypropylenes , Surgical Mesh , Syndrome , Time Factors , Tomography, X-Ray Computed
4.
Protein Expr Purif ; 15(2): 202-6, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10049676

ABSTRACT

Bax is a proapoptotic ion channel forming protein of the Bcl-2 family. In cells the protein is found in the cytosol and in the mitochondria membrane where it presumably is involved during apoptosis in disruption of the mitochondrial membrane potential and release of cytochrome c. The protein has a hydrophobic domain at the C-terminus, which renders it a limited solubility. Thus, all studies on recombinant Bax has so far been performed on C-terminal truncated protein. We have expressed and purified the full-length human Bax alpha. The protein was expressed with a His tag at the N-terminus and purified by affinity chromatography on Ni-NTA-agarose followed by ion-exchange chromatography on Q-Sepharose. The protein was more than 98% pure on SDS-PAGE and in the presence of 1% (w/v) octyl glucoside it could be concentrated up to 0.5 mg/ml. Full-length Bax was 25-fold more efficient, compared to C-terminal truncated Bax, in forming ion channels and trigger carboxyfluorescein release from liposomes.


Subject(s)
Proto-Oncogene Proteins c-bcl-2 , Proto-Oncogene Proteins/isolation & purification , Amino Acid Sequence , Apoptosis/genetics , Base Sequence , Chromatography, Affinity , Chromatography, Ion Exchange , Escherichia coli , Fluoresceins , Fluorescent Dyes , Genetic Vectors/genetics , Humans , Ion Channels/metabolism , Liposomes , Molecular Sequence Data , Peptide Fragments/biosynthesis , Peptide Fragments/isolation & purification , Peptide Fragments/pharmacology , Proto-Oncogene Proteins/biosynthesis , Proto-Oncogene Proteins/genetics , Proto-Oncogene Proteins/pharmacology , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/pharmacology , Solubility , bcl-2-Associated X Protein
5.
J Cell Biol ; 143(1): 217-24, 1998 Oct 05.
Article in English | MEDLINE | ID: mdl-9763433

ABSTRACT

Bcl-2 family members either promote or repress programmed cell death. Bax, a death-promoting member, is a pore-forming, mitochondria-associated protein whose mechanism of action is still unknown. During apoptosis, cytochrome C is released from the mitochondria into the cytosol where it binds to APAF-1, a mammalian homologue of Ced-4, and participates in the activation of caspases. The release of cytochrome C has been postulated to be a consequence of the opening of the mitochondrial permeability transition pore (PTP). We now report that Bax is sufficient to trigger the release of cytochrome C from isolated mitochondria. This pathway is distinct from the previously described calcium-inducible, cyclosporin A-sensitive PTP. Rather, the cytochrome C release induced by Bax is facilitated by Mg2+ and cannot be blocked by PTP inhibitors. These results strongly suggest the existence of two distinct mechanisms leading to cytochrome C release: one stimulated by calcium and inhibited by cyclosporin A, the other Bax dependent, Mg2+ sensitive but cyclosporin insensitive.


Subject(s)
Cytochrome c Group/metabolism , Intracellular Membranes/physiology , Magnesium/metabolism , Mitochondria, Liver/physiology , Proto-Oncogene Proteins/metabolism , Animals , Bongkrekic Acid/pharmacology , COS Cells , Cyclosporine/pharmacology , Female , HeLa Cells , Humans , Magnesium/pharmacology , Mice , Mice, Inbred Strains , Mitochondria, Liver/drug effects , Permeability , Proto-Oncogene Proteins c-bcl-2/metabolism , Recombinant Proteins/metabolism , Transfection , bcl-2-Associated X Protein
6.
Science ; 277(5324): 370-2, 1997 Jul 18.
Article in English | MEDLINE | ID: mdl-9219694

ABSTRACT

Proteins of the Bcl-2 family are intracellular membrane-associated proteins that regulate programmed cell death (apoptosis) either positively or negatively by as yet unknown mechanisms. Bax, a pro-apoptotic member of the Bcl-2 family, was shown to form channels in lipid membranes. Bax triggered the release of liposome-encapsulated carboxyfluorescein at both neutral and acidic pH. At physiological pH, release could be blocked by Bcl-2. Bcl-2, in contrast, triggered carboxyfluorescein release at acidic pH only. In planar lipid bilayers, Bax formed pH- and voltage-dependent ion-conducting channels. Thus, the pro-apoptotic effects of Bax may be elicited through an intrinsic pore-forming activity that can be antagonized by Bcl-2.


Subject(s)
Ion Channels/physiology , Proto-Oncogene Proteins c-bcl-2/physiology , Proto-Oncogene Proteins/physiology , Animals , Apoptosis , Cell Membrane Permeability , Cells, Cultured , Erythrocytes/cytology , Fluoresceins/metabolism , Hemolysis , Humans , Hydrogen-Ion Concentration , Lipid Bilayers , Liposomes , Membrane Potentials , Neurons/cytology , Patch-Clamp Techniques , Proto-Oncogene Proteins/pharmacology , Proto-Oncogene Proteins c-bcl-2/antagonists & inhibitors , Proto-Oncogene Proteins c-bcl-2/pharmacology , Sheep , Sympathetic Nervous System/cytology , bcl-2-Associated X Protein
7.
Protein Expr Purif ; 9(1): 61-8, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9116503

ABSTRACT

Escherichia coli remains an organism of choice for the production of recombinant proteins required in large quantities. Whenever possible, secretion is the preferred strategy since it permits easy and efficient purification from the extracellular medium. Our efforts to use E. coli to secrete a human CD23 soluble variant fused to a pair of IgG binding domains via the Staphylococcal protein A signal peptide were unsuccessful. Surprisingly, when the same construct was expressed in the baculovirus system, efficient secretion was observed and cleavage of the signal peptide occurred at the expected site. Varying the genes in the fusions or the tags, or the topology of the gene and the tag, did not affect the high-level secretion and cleavage at the correct site. We envision that fusion of the bacterial signal sequence to eukaryotic recombinant genes will prove to be a tool of value for efficient protein secretion in insect cells using the baculovirus expression system.


Subject(s)
Baculoviridae/genetics , Protein Sorting Signals/genetics , Receptors, IgE/genetics , Recombinant Fusion Proteins/metabolism , Staphylococcal Protein A/genetics , Amino Acid Sequence , Animals , Biological Transport , Cell Compartmentation , Endoplasmic Reticulum , Eukaryotic Cells , Humans , Mice , Molecular Sequence Data , Prokaryotic Cells , Protein Engineering/methods , Spodoptera/cytology , Spodoptera/virology
8.
Eur Respir J Suppl ; 22: 63s-66s, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8871046

ABSTRACT

At least two cell-derived signals have been shown to be necessary for the induction of immunoglobulin isotype switching in B-cells. The first signal is given by either of the soluble lymphokines, interleukin (IL)-4 or IL-13, which induce germline epsilon transcript expression, but this alone is insufficient to trigger secretion of immunoglobulin E (IgE). The second signal is provided by a physical interaction between B-cells and activated T-cells, basophils and mast cells, and it has been shown that the CD40/CD40 ligand (CD40L) pairing is crucial for mediating IgE synthesis. In hyper-immunoglobulin M1 (HIGM1) syndrome, which is characterized by greatly decreased levels of immunoglobulin G, A and E (IgG, IgA and IgE), there are mutations in the CD40L resulting in a completely non-functional extracellular domain. The CD40L is, therefore, playing a central role in immunoglobulin isotype switching. Amongst the numerous pairs of surface adhesion molecules, the CD23-CD21 pair seems to play a key role in the generation of IgE. The CD23 molecule is positively and negatively regulated by factors which increase or decrease IgE production, respectively. Antibodies to CD23 have been shown to inhibit IL-4-induced human IgE production in vitro and to inhibit antigen-specific IgE responses in a rat model, in an isotype selective manner. CD23 interacts with CD21 on B-cells, preferentially driving IgE production. CD23 recognizes two main epitopes on the CD21 molecule. One region consists of short consensus repeat (SCR) sequences 1-2 and the other of SCR 5-8. In the latter region, Asn 370 and 295 are critical in the interaction with the lectin CD23. Therefore, a restricted number of cytokines and surface molecules seems to selectively regulate human immunoglobulin E synthesis.


Subject(s)
Antigens, Surface/immunology , CD40 Antigens/immunology , Hypergammaglobulinemia/immunology , Immunoglobulin Class Switching/immunology , Immunoglobulin E/biosynthesis , Immunoglobulin M/biosynthesis , Receptors, Complement 3d/immunology , Receptors, IgE/immunology , Animals , Antigens, Surface/physiology , B-Lymphocytes/immunology , CD40 Antigens/genetics , CD40 Antigens/physiology , Eosinophils/immunology , Humans , Immunoglobulin A/biosynthesis , Immunoglobulin G/biosynthesis , Interleukin-13/immunology , Interleukin-4/immunology , Mast Cells/immunology , Rats , Receptors, Complement 3d/physiology , Receptors, IgE/genetics , Receptors, IgE/physiology , Signal Transduction , Syndrome
9.
J Electrocardiol ; 29(1): 39-44, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8808524

ABSTRACT

Elderly people, even if asymptomatic and in apparently good cardiovascular condition, have a high incidence of cardiovascular events. Prognostic markers by noninvasive procedures would therefore be desirable. The aim of this study was to evaluate the prognostic usefulness of Holter monitoring in this setting. Holter findings in 50 asymptomatic elderly subjects with sinus rhythm were correlated with major clinical cardiovascular events occurring during a 5-year follow-up period (16% incidence). No significant association was found with any baseline arrhythmia category, even complex arrhythmias such as unsustained ventricular tachycardia, which had a 10% baseline prevalence. On the other hand, cardiovascular events were correlated (P < .01) with the presence of silent ST-segment depression (8% baseline prevalence), which seems to have an unfavorable clinical significance, in elderly, as well as younger, people. Holter monitoring, because of the benignity of high-prevalence findings and the very low incidence of unfavorable events, has an overall limited prognostic usefulness in asymptomatic elderly subjects with sinus rhythm. In a cost-conscious medical environment, its use seems to be justified only in selected cases.


Subject(s)
Arrhythmia, Sinus/diagnosis , Electrocardiography, Ambulatory , Aged , Arrhythmia, Sinus/etiology , Arrhythmia, Sinus/physiopathology , Female , Follow-Up Studies , Humans , Male , Prevalence , Prognosis
10.
Eur J Immunol ; 25(3): 863-5, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7705419

ABSTRACT

CD40 ligand (CD40L), a surface molecule which can be expressed by T cells, mast cells and basophils, has been shown to be involved in the control of B cell proliferation, immunoglobulin class switching as well as in the activation of monocytes and T cells. We demonstrate that CD40L can also be expressed constitutively by eosinophils from an hypereosinophilic patient or, upon activation, by the eosinophilic cell line EOL-3 and normal blood eosinophils. Eosinophils were able to induce, in conjunction with IL-4, CD40L-dependent B cell proliferation in vitro. These results suggest that CD40L could play a role in the inflammatory processes during which eosinophil infiltration and activation are observed.


Subject(s)
Eosinophils/immunology , Membrane Glycoproteins/biosynthesis , B-Lymphocytes/immunology , Blotting, Northern , CD40 Ligand , Cell Line , Humans , Hypereosinophilic Syndrome/immunology , Lymphocyte Activation/immunology , Polymerase Chain Reaction , RNA, Messenger/biosynthesis
11.
J Biol Chem ; 270(13): 7025-8, 1995 Mar 31.
Article in English | MEDLINE | ID: mdl-7706236

ABSTRACT

CD40 ligand (CD40L) is expressed on the surface of activated CD4+ T cells, basophils, and mast cells. Binding of C40L to its receptor, CD40, on the surface of B cells stimulates B cell proliferation, adhesion and differentiation. A preparation of soluble, recombinant CD40L (Tyr-45 to Leu-261), containing the full-length 29-kDa protein and two smaller fragments of 18 and 14 kDa, has been shown to induce differentiation of B cells derived either from normal donors or from patients with X-linked hyper-IgM syndrome (Durandy, A., Schiff, C., Bonnefoy, J.-Y., Forveille, M., Rousset, F., Mazzei, G., Milili, M., and Fischer, A. (1993) Eur. J. Immunol. 23, 2294-2299). We have now purified each of these fragments to homogeneity and show that only the 18-kDa fragment (identified as Glu-108 to Leu-261) is biologically active. When expressed in recombinant form, the 18-kDa protein exhibited full activity in B cell proliferation and differentiation assays, was able to rescue of B cells from apoptosis, and bound soluble CD40. Sucrose gradient sedimentation shows that the 18-kDa protein sediments as an apparent homotrimer, a result consistent with the proposed trimeric structure of CD40L. This demonstrates that a soluble CD40L can stimulate CD40 in a manner indistinguishable from the membrane-bound form of the protein.


Subject(s)
Antigens, CD/metabolism , B-Lymphocytes/immunology , Membrane Glycoproteins/biosynthesis , Amino Acid Sequence , Animals , Antibody Formation , Apoptosis , CD40 Ligand , Cell Line , Glutamic Acid , Haplorhini , Humans , Immunoglobulin M/biosynthesis , Immunologic Deficiency Syndromes/immunology , Interleukin-4/pharmacology , Kidney , Leucine , Ligands , Lymphocyte Activation , Macromolecular Substances , Membrane Glycoproteins/isolation & purification , Membrane Glycoproteins/pharmacology , Mice , Molecular Weight , Palatine Tonsil/immunology , Polymerase Chain Reaction , Recombinant Proteins/biosynthesis , Recombinant Proteins/isolation & purification , Recombinant Proteins/pharmacology , Reference Values , Sequence Homology, Amino Acid , Transfection
12.
Cytotechnology ; 18(3): 183-92, 1995 Jan.
Article in English | MEDLINE | ID: mdl-22358744

ABSTRACT

We demonstrate here that transient expression with COS cells can be performed at the one litre scale for a period of more than 10 days. Cells grown in T225 flasks were transfected by electroporation, transferred into spinners, and then grown either in suspension or on microcarriers. A daily medium change significantly extented culture life and production time, compared with standard protocols.Concentrations of the product, the secreted fusion protein CD40-Fc, were comparable in microcarrier and suspension culture. Cultures were started in fetal calf serum containing medium and the subsequent production process was performed in a low protein serum free medium which allowed easy downstream processing. 10 litres of supernatant, collected from one transfected batch of cells, yielded 30 mg of purified and biologically active protein.In addition to developing a simplified protocol for generation of cells we also reduced the material (DNA, cuvettes) required for electroporation. Our results show that scale up of transient expression to the litre scale can be successfully acieved. This provides a new tool to generate milligram quantities of protein within weeks of gene cloning.

13.
J Exp Med ; 180(5): 1775-84, 1994 Nov 01.
Article in English | MEDLINE | ID: mdl-7964460

ABSTRACT

The induction of immunoglobulin E (IgE) switching in B cells requires at least two signals. The first is given by either of the soluble lymphokines interleukin 4 (IL-4) or IL-13, whereas the second is contact dependent. It has been widely reported that a second signal can be provided by the CD40 ligand (CD40L) expressed on the surface of T cells, mast cells, and basophils. A defect in the CD40L has been shown recently to be responsible for the lack of IgE, IgA, and IgG, characteristic of the childhood X-linked immunodeficiency, hyper IgM syndrome (HIGM1). IgE can however be detected in the serum of some HIGM1 patients. In this study, we isolated T cell clones and lines using phytohemagglutinin (PHA) and allergen, respectively, from the peripheral blood of one such patient who expressed a truncated form of CD40L, and investigated their ability to induce IgE switching in highly purified, normal tonsillar B cells in vitro. Unexpectedly, 4 of 12 PHA clones tested induced contact-dependent IgE synthesis in the presence of exogenous IL-4. These clones were also shown to strongly upregulated IL-4-induced germline epsilon RNA and formed dense aggregates with B cells. Of the four helper clones, three were CD8+, of which two were characteristic of the T helper cell 2 (Th2) subtype. Two allergen-specific HIGM1 T cell lines, both of the Th0 subtype, could also drive IgE synthesis when prestimulated using specific allergen. All clones and lines were negative for surface expression of CD40L, and the mutated form of CD40L was confirmed for a representative clone by RNase protection assay and sequencing. The IgE helper activity could not be attributed to membrane tumor necrosis factor alpha (TNF-alpha) although it was strongly expressed on activated clones, and the addition of neutralizing anti-TNF-alpha antibody did not abrogate IgE synthesis. These results therefore suggest the involvement of T cell surface molecules other than CD40L in the induction of IgE synthesis, and that these molecules may also be implicated in other aspects of T-B cell interactions.


Subject(s)
Genetic Linkage , Hypergammaglobulinemia/immunology , Immunoglobulin E/biosynthesis , Membrane Glycoproteins/physiology , T-Lymphocytes/physiology , X Chromosome , Base Sequence , CD40 Ligand , Cell Line , Child , Clone Cells , Humans , Hypergammaglobulinemia/genetics , Lymphokines/analysis , Male , Membrane Glycoproteins/genetics , Molecular Sequence Data , RNA, Messenger/analysis , T-Lymphocytes/immunology , Tumor Necrosis Factor-alpha/analysis
15.
Immunology ; 81(1): 111-4, 1994 Jan.
Article in English | MEDLINE | ID: mdl-7510662

ABSTRACT

A mutagenized subclone of the murine EL-4 thymoma (clone B5) is approximately 30 times more potent than parental EL-4 cells in stimulating proliferation and Ig secretion of murine or human B cells by direct cell contact in the presence of appropriate cytokines. In this study we found that CD40 ligand (CD40L) expression was constitutive and very similar on EL-4 B5 and parental EL-4 cells according to Northern blot and flow cytometry. Activation with phorbol 12-myristate 13-acetate (PMA) alone, PMA and ionomycin, interleukin-1 (IL-1) or human T-cell supernatant did not lead to significant CD40L up-regulation. A receptor-binding assay with soluble CD40 did not reveal different ligand affinities. However, murine and human soluble CD40-IgFc fusion proteins inhibited human B-cell stimulation by EL-4 B5 cells in the presence of human T-cell supernatant. Inhibition was 96% when soluble CD40 was added on day 0 of culture and progressively decreased when the CD40 was added subsequently. Ig secretion by cytoplasmic Ig-positive cells was no longer inhibited. These findings imply that, although CD40 ligand is necessary for B-cell activation by EL-4B5 cells, additional molecule(s) must be responsible for the increased helper activity of the EL-4 B5 clone.


Subject(s)
Antigens, CD/analysis , Antigens, Differentiation, B-Lymphocyte/analysis , B-Lymphocytes/immunology , Lymphocyte Cooperation/immunology , T-Lymphocytes, Helper-Inducer/immunology , Animals , Blotting, Northern , CD40 Antigens , Humans , Ligands , Lymphocyte Activation/immunology , Mice , Mutation , Thymoma/immunology , Thymus Neoplasms/immunology , Tumor Cells, Cultured
16.
Curr Opin Immunol ; 5(6): 944-9, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8297528

ABSTRACT

Following advances during the past 5 years in our understanding of the molecular structure of receptors for IgE, progress has been made in elucidating the structure and function of IgE receptors and the signalling events through these receptors. IgE is not the only ligand for some of these receptors, leading to their having unexpected and interesting biological activities.


Subject(s)
Receptors, IgE/physiology , Animals , Humans , Receptors, IgE/chemistry , Signal Transduction/immunology
17.
Eur J Immunol ; 23(9): 2294-9, 1993 Sep.
Article in English | MEDLINE | ID: mdl-7690328

ABSTRACT

We studied the ability of B lymphocytes from patients with X-linked hyper IgM syndrome (HIGM1) to be activated via the CD40 membrane receptor. HIGM1 is caused by a CD40 ligand gene mutation, leading to defective expression on the membrane of activated T lymphocytes. We found that triggering of B cells by an anti-CD40 monoclonal antibody or the soluble CD40 ligand plus interleukin (IL)-4 or IL-10 led to B cell proliferation and/or differentiation towards IgG, IgA and IgE secretion. This was reflected by transcription of C gamma, alpha and epsilon membrane isotype expression and IgG, IgA and IgE production. These results confirm the integrity of B cells in patients with the HIGM1 immunodeficiency and open up new therapeutic possibilities.


Subject(s)
Antibodies, Monoclonal/immunology , Antigens, CD/immunology , Antigens, Differentiation, B-Lymphocyte/immunology , B-Lymphocytes/immunology , Hypergammaglobulinemia/immunology , Immunoglobulins/biosynthesis , Membrane Glycoproteins/immunology , Base Sequence , CD40 Antigens , CD40 Ligand , Child , Child, Preschool , Cytokines/pharmacology , Genetic Linkage , Humans , Hypergammaglobulinemia/genetics , Immunoglobulin M/analysis , Ligands , Lymphocyte Activation , Male , Molecular Sequence Data , X Chromosome
18.
Nature ; 365(6444): 340-3, 1993 Sep 23.
Article in English | MEDLINE | ID: mdl-7690905

ABSTRACT

Immunoglobulin E (IgE) is central to the induction of allergic diseases through its binding to the high-affinity receptor (Fc epsilon R1) on mast cells and basophils. Crosslinking by allergens of the bound IgE leads to the release of various inflammatory mediators. IgE production by B cells requires a physical interaction with T cells, involving a number of surface adhesion molecules, as well as the soluble factors interleukin-4 (IL-4) and IL-13 (ref. 5) produced by T cells, basophils and mast cells. Here we report that, in the presence of IL-4, mast and basophilic cell lines can provide the cell contact signals that are required for IgE synthesis. The human cell lines HMC-1 (mast) and KU812 (basophilic) both express the ligand for CD40 (CD40L) which is shown to be responsible for the IgE production. Moreover, freshly isolated purified human lung mast cells and blood basophils are also shown to express CD40L and to induce IgE production. This evidence suggests that mast cells and basophils may therefore play a key role in allergy not only by producing inflammatory mediators, but also by directly regulating IgE production independently of T cells.


Subject(s)
B-Lymphocytes/metabolism , Basophils/physiology , Immunoglobulin E/biosynthesis , Mast Cells/physiology , Animals , Antigens, CD/metabolism , Antigens, Differentiation, B-Lymphocyte/metabolism , Base Sequence , Blood , CD40 Antigens , CD40 Ligand , Cell Communication , Cell Line , Cyclosporine/pharmacology , DNA, Single-Stranded , Humans , Interleukin-4/physiology , Ligands , Lung/cytology , Membrane Glycoproteins/biosynthesis , Membrane Glycoproteins/metabolism , Molecular Sequence Data , Palatine Tonsil/cytology , Skin/cytology , T-Lymphocytes/physiology
19.
J Biol Chem ; 268(10): 7401-6, 1993 Apr 05.
Article in English | MEDLINE | ID: mdl-8463273

ABSTRACT

A protein kinase C homologue of Schizosaccharomyces pombe, pkc1+, was isolated from a genomic library by screening with the Saccharomyces cerevisiae PKC1 probe. From its primary sequence and biochemical properties, we conclude that S. pombe pkc1+ encodes a phospholipid-activated Ca(2+)-independent protein kinase, homologous to the delta/epsilon classes of mammalian protein kinase C. Gene disruption experiments show that pkc1+ is not essential for cell viability; however, overexpression of the protein leads to an abnormal cell morphology and a block in cell separation following mitosis suggestive of a role in cell division. In vitro phosphorylation experiments reveal several potential pkc1+ substrates.


Subject(s)
Calcium/metabolism , Protein Kinase C/metabolism , Schizosaccharomyces/enzymology , Amino Acid Sequence , Base Sequence , Blotting, Northern , DNA, Fungal , Molecular Sequence Data , Phenotype , Protein Kinase C/genetics , Restriction Mapping , Schizosaccharomyces/genetics
20.
FEBS Lett ; 315(3): 259-66, 1993 Jan 11.
Article in English | MEDLINE | ID: mdl-7678552

ABSTRACT

Here we report the cloning of the cDNA for human CD40-Ligand (CD40-L) from a CD4-positive T cell clone. The deduced amino acid sequence predicts a type II membrane protein of 261 amino acids. Northern blot and FACS analysis of PBMNC revealed that the human CD40-L can be detected on T cells and is absent from B cells and monocytes. The human CD40-L is expressed on both CD4- and CD8-positive T cells, (CD45R0+) and (CD45RA+) subsets. We observed that IL-4, an inducer of IgE production, upregulated CD40-L mRNA level while IFN gamma, an inhibitor of IgE synthesis, reduced the expression of CD40-L mRNA. These data suggest a the correlation between human CD40-L expression and IgE production.


Subject(s)
Antigens, CD , Antigens, Differentiation, B-Lymphocyte , Gene Expression Regulation , Immunoglobulin E/biosynthesis , Membrane Glycoproteins/genetics , Amino Acid Sequence , Base Sequence , Blotting, Northern , CD40 Antigens , CD40 Ligand , Cells, Cultured , Cloning, Molecular , Cytokines/physiology , DNA , Flow Cytometry , Humans , Ligands , Molecular Sequence Data , Neutrophils/metabolism , RNA, Messenger/genetics , Sequence Homology, Amino Acid
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