bluuebunny/crossref_metadata_2025 huggingface dataset:
Monoclonal IgG Antibodies Influence the Migration Patterns of Lymphocytes in vivo
Authors: Yousaf Nasim , Williams Bryan D.
Published: April 2003

Monoclonal antibodies (MoAb) are useful therapeutic agents for the treatment of a variety of human disorders, although the effector mechanisms responsible for the outcome of an efficient immunotherapy remain unclear. This study was designed to address the early effects of MoAb on the migration patterns of lymphocytes in vivo. The clearance profiles and tissue distribution of 111In–labelled rat lymph node cells were examined in both normal and decomplemented allogeneic and semi–allogeneic recipients pre–injected with IgG2b (R3/13) or IgG2a (R2/15S) MoAb directed against the RT1Aa, the classical class I major histocompatibility complex antigen of the DA rat. Both MoAb were equally effective in not only augmenting the removal of DA and (DA × PVG)F1 cells from the circulation and promoting their subsequent localization within the liver but also causing a significant degree of cell lysis during the early phase of cell clearance, even in decomplemented recipients. Although R3/13 and R2/15S are known to target erythrocytes differently in normal and cobra venom factor (CVF)–treated animals, no differences were observed in the migration behaviour of lymph node cells in allogeneic or semi–allogeneic hosts pre–injected with the same MoAb. Since rat lymphocytes express a much higher level of the RT1Aa antigen as compared with erythrocytes, we could not exclude a possible role of residual complement components in the circulation of CVF–treated rats that may have accounted for the observed antibody–dependent effects on target lymphocytes. On the basis of these findings we believe that the design and methodology employed in our present experimental opsonization system were inadequate to define clearly the mechanisms responsible for antibody–mediated removal and destruction of target lymphocytes in vivo.
Mechanisms and Pharmacologic Control of Basophil–Derived IL–4 and IL–13
Authors: Schroeder J.T. , MacGlashan Jr. D.W. , Lichtenstein L.M.
Published: April 2003

Human basophils represent a major source of interleukin (IL) 4 and 13 protein, cytokines which share several biological activities central to the pathogenesis of allergic inflammation. Studies show that the production of these cytokines differs with respect to mode of activation and the time course of their secretion. Pharmacologic evidence indicates that IL–4 generation, which is most prominent with IgE–dependent activation, is mediated through a calcineurin–dependent pathway. In contrast, multiple pathways seem evident in the regulation of IL–13 in basophils.
Role of the Th2 Cytokines in the Development of Allergen–Induced Airway Inflammation and Hyperresponsiveness
Authors: Hamelmann Eckard , Wahn Ulrich , Gelfand Erwin W.
Published: April 2003

Increased production of interleukin (IL)–4 and IL–5 by T–helper cells may be pivotal for the induction and regulation of allergic diseases. We have studied the role of IL–4 and IL–5 in the development of eosinophilic airway inflammation (AI) and airway hyperresponsiveness (AHR) in a mouse model of allergen–induced bronchial asthma. Utilizing different modes of sensitization, we delineated the importance of IL–5–mediated eosinophilic airway infiltration for the development of in vitro and in vivo AHR and demonstrated the inhibition of airway inflammation and AHR by anti–IL–5 antibody treatment. Studies in IL–4– and IL–5 deficient mice revealed the importance of both cytokines for the induction of AI and AHR independently from the production of allergen–specific IgE, and indicated these cytokines as potential targets in novel approaches in the treatment of asthma.
TNF–· and IL–5 Gene Induction in IgE plus Antigen–Stimulated Mast Cells Require Common and Distinct Signaling Pathways
Authors: Baumruker T. , Csonga R. , Jaksche D. , Novotny V. , Prieschl E.E.
Published: April 2003

Background: Mast cells produce a variety of cytokines and chemokines in a timely and tightly controlled fashion if stimulated via the FcεRI. Evidence is accumulating that the transcriptional induction of the corresponding genes and the release of these mediators are dependent on common and mediator–specific components of the signal transduction and transcription factor machinery. Methods: We addressed this issue by comparing the effects of mitogen activated protein (MAP) kinase pathway inhibitors and protein kinase C (PKC) inhibitors on the induction of TNF–α and IL–5 after IgE plus antigen (Ag) stimulation in CPII mouse mast cells using Western blot analyses and transient transfections of reporter gene plasmids. Results: TNF–α shows a strict dependence on the MAP kinase pathway, while IL–5 is either activated by PMA–dependent PKCs or along the MAP kinase pathway. In addition, both mediators are sensitive to PKCμ inhibition, suggesting involvement of this atypical, non–PMA dependent PKC in the overall induction process. Conclusion: While the two cytokines were recently shown to be regulated by a member of the nuclear factor of activated T–cells (NF–AT) transcription factor family, activator protein 1 (AP1) was identified as a cofactor at the TNF–α promoter while a GATA family member comprised the cofactor at the IL–5 promoter. This suggests that the differences in requirement for signal transduction cascades are the result of a different usage of NF–AT cofactors for transcription of each cytokine in mast cells.
A New Paradigm of T Cell Allergy: Requirement for the B–1 Cell Subset
Authors: Askenase Philip W. , Kawikova I. , Paliwal V. , Akahira-Azuma M. , Gerard C. , Hugli T. , Tsuji R.
Published: April 2003

Background: We have uncovered a role for B–1–B–cell–produced IgM antibody, in the initiation of contact sensitivity (CS) in mice. CS and delayed–type hypersensitivity (DTH) involve recruitment of T cells to the tissues, to be activated by antigen–presenting cells (APC), and then make cytokines. Little is known about low recruitment is initiated. In CS, soon after immunization, the unique B–1 cell subset, responsible for the formation of most IgM, is activated to produce antigen (Ag)–specific IgM for export to tissues. IgM forms complexes with challenge Ag, activating the classical complement (C) pathway, generating C5a, to activate endothelium directly, or indirectly via C5a receptors (R) on mast cells and platelets, that release vasoactive amines (serotonin) and cytokines (TNF–α). These act together to induce vasodilatation, vascular permeability and expression of endothelial adhesion molecules to promote optimal T cell recruitment. Methods and Results: New findings that established this pathway include: (1) absent CS response in C–deficient, or C–inhibited mice; (2) local generation of C5a in CS tissue extracts; (3) absent CS in C5aR–/– mice; (4) decreased CS in B cell and B–1–cell–deficient mice, and (5) reconstitution of CS by transfer of B–1 cells, or hapten–specific IgM. Conclusion: These findings indicate that the B–1 subset producing Ag–specific IgM is required early in CS to activate C, to induce vasoactive mediators that initiate local T recruitment.
Effects of Inflammatory Neuropeptides on the Arachidonate Cascade of Platelets
Authors: Gecse Árpád , Kis Béla , Mezei Zsófia , Telegdy Gyula
Published: April 2003

Background: During neurogenic inflammation, neuro–peptides (substance P, SP, calcitonin gene–related peptide, CGRP, and neurokinin A) are released from nerve endings, and these peptides initiate inflammatory reactions in the microcirculation. Platelets are one of the most important elements of the microcirculation. Methods: Our in vitro experiments were carried out to determine the effects of inflammatory neuropeptides (SP, and CGRP) on the arachidonate cascade of isolated rat platelets. Cells were labeled with 1–14C–arachidonic acid, then the eicosanoids were separated with overpressure thin–layer chromatography or high–performance liquid chromatography and were quantitatively determined with a liquid scintillation analyzer. Results: SP (10–9 and 10–8 mol/l) significantly increased the activity of the arachidonate cascade. The lipoxygenase pathway was significantly stimulated by SP (10–11, 10–9 and 10–8 mol/l), while the cyclooxygenase system was inhibited by 10–12 mol/l, and stimulated by 10–9 mol/l SP. The dose–response curve of TxA2 to SP exhibited a similar pattern to that detected for the cyclooxygenase pathway. Among the vasodilator cyclooxygenase metabolites, only the synthesis of PGE2 was significantly elevated by SP (10–9 mol/l ). CGRP either in low (10–12–10–11 mol/l) or in high concentrations (10–6 mol/l) activated the cyclooxygenase pathway, while it had no effect on the lipoxygenase pathway. CGRP (8–37), a specific CGRP1 receptor antagonist, inhibited the effects of CGRP. Conclusions: Our data suggest that the arachidonate metabolites of platelets may play a role in the process of neurogenic inflammation.
The Apparent Monovalency of Human IgG4 Is Due to Bispecificity
Authors: Aalberse Rob C. , Schuurman Janine , van Ree Ronald
Published: April 2003

A hypothesis is put forward to explain the apparent monovalency of human IgG4. It is based upon the known instability of the IgG4 hinge. IgG4 is secreted as a regular bivalent antibody, but after secretion interacts with another IgG4 molecule. This interaction results in the exchange of half molecules (a combination of one heavy chain and one light chain) between the two IgG4 molecules. The postulated bispecific IgG4 antibodies can indeed be found in selected human sera following repeated immunization with two non–crossreacting antigens.
Promoter Polymorphism in the Candidate Genes, IL–4, IL–9, TGF–β1, for Atopy and Asthma
Authors: Rosenwasser Lanny J.
Published: April 2003

This paper will review genetic variations in the structure of three important candidate genes with varying effects in atopy and asthma that may have significant overall susceptibility associations in relation to the development of atopy and asthma. The three cytokine genes involved are interleukin (IL)–4, IL–9 and transforming growth factor β1, and the nature of the polymorphisms may be related to significantly higher outputs of these cytokines in atopy and asthma.
Regulatory Mechanisms of Human T Cell IL–5 Synthesis: Differential Roles of the Proximal Promoter–Binding Proteins in IL–5 Gene Transcription
Authors: Mori Akio , Kaminuma Osamu , Ogawa Koji , Kobayashi Noriaki , Akiyama Kazuo , Okudaira Hirokazu
Published: April 2003

Background: IL–5 is crucially involved in eosinophilic inflammation. We have previously reported that IL–5 synthesis by atopic and nonatopic asthmatics is significantly enhanced compared to control subjects. T cell IL–5 synthesis is regulated at the transcriptional level. The proximal human IL–5 promoter (–62 to –46) homologous to the conserved lymphokine element 0 (CLE0) is essential for activation–induced gene transcription by Th cells. Methods: Luciferase reporter analysis and gel shift analysis were performed. Results: The CLE0 homologous element is the overlapping binding site for a constitutive and an inducible binding factor. Site–directed mutagenesis successfully differentiated the two bindings, and revealed that the transcriptional induction was ascribed to the inducible binding, while the constitutive binding was rather inhibitory. A mutant element which lost the constitutive binding, but retained the inducible binding, exerted 3 times more transcriptional activity compared to the wild–type element. In contrast, another mutant element which lost the inducible binding and retained the constitutive binding exhibited no transcriptional induction. Gel shift analysis was performed to clarify that the inducible binding was more prominent and the constitutive binding was less in IL–5 producing Th clones compared to IL–5–nonproducing clones. Conclusion: The ratio of the inducible/constitutive binding to the CLE0 homologous element may determine the capacity of human Th cells to transcribe the IL–5 gene.
Positional Candidate Gene Approach and Functional Genomics Strategy in Atopy Gene Discovery
Authors: Nickel R.G. , Saitta F.P. , Freidhoff L.R. , Yu X.Y. , Ehrlich E. , Barnes K.C. , Beaty T. , Huang S.K.
Published: April 2003

As part of our effort in searching for genetic factors contributing to the susceptibility to atopy and asthma, we have focused on a ‘positional candidate’ approach in identifying CC chemokine gene polymorphisms and their functional correlates. To date, a single–nucleotide polymorphism was found in the RANTES proximal promoter region, and a high degree of sequence variation was identified in the 3′–untranslated region –of the eotaxin gene. Also, we are pursuing a series of functional genomics’ studies designed to identify differentially expressed genes in a panel of allergen–specific human Th2 cells and in antigen–induced hyperreactive murine airways. This is performed using a combination of protocols including suppression–subtractive hybridization and cDNA array hybridizations with 18,363 nonredundant sequences. A data base is being generated from a list of subtracted cDNA sequences and array–positive clones to categorize differentially expressed genes. Sequences are being placed in biologically relevant categories on the basis of function (i.e., receptor, signal transduction pathways, transcription, and translation). With the increasing amount of sequence information compiled by the Human Genome Project, it will be particularly challenging to integrate functional gene–mapping efforts to define and compare aberrant genotypes/phenotypes in atopic diseases.
Regulation of Proinflammatory Cytokines in Seasonal Allergic Rhinitis
Authors: Bachert Claus , van Kempen Muriel , van Cauwenberge Paul
Published: April 2003

Background: Mediators and cytokines have been demonstrated to be released due to nasal allergen exposure in sensitized subjects, but little is known about the release of cytokines and their antagonists under natural conditions. Methods: Mediators – histamine, eosinophilic cationic protein (ECP), leukotrienes (LT) C4/ D4/E4 – and cytokines – interleukin (IL)–1β, IL–8, IL–1 receptor antagonist (ra) – were measured in nasal secretions throughout the grass pollen season (6 visits) and for 6 weeks thereafter (3 visits) in patients with seasonal allergic rhinitis (n = 13) and compared to controls (n = 12). A second study was performed comparing nasal secretions of 13 subjects allergic to house dust mite to 8 controls. Results: Compared to controls, leukotrienes and ECP were significantly elevated at nearly all time points in and postseason in the allergic group. Whereas IL–1β was significantly elevated throughout the study period, IL–1ra was significantly decreased from visit 1 to 3. IL–8 showed no increase compared to controls. Data from subjects with perennial allergic rhinitis supported these findings and additionally demonstrated decreased concentrations of IL–8 and myeloperoxidase in secretions compared to controls. Conclusion: Allergic rhinitis represents a persistent inflammation in terms of an activation of eosinophils and constant upregulation of the proinflammatory cytokine IL–1β in the pollen season and thereafter. We additionally could demonstrate a dysfunction of the anti–inflammatory capacity, i.e. IL–1ra, a naturally occurring antagonist. Persistent inflammation may furthermore lead to the dysregulation of local cellular immunity by reducing the number and activity of neutrophils on the mucosal surface.
Hypothetical Mechanisms of Action of an H1–Antihistamine in Asthma
Authors: Rihoux J.P. , Michel L. , Arnold R. , König W.
Published: April 2003

Some recent clinical studies carried out with the potent H1–antihistamine cetirizine (CTZ) suggest that this drug could be useful for the treatment of mild to moderate asthma and even for the prevention of the disease. Besides a potent antagonism of H1–receptors at bronchial level, this drug was also shown to exert a large series of anti–inflammatory effects in in vitro, ex vivo and in vivo pharmacological models and also in clinical situations in atopic subjects. All the data collected up to now suggest the possible existence in the molecule of a central key mechanism of action on resident cells especially involved in cell trafficking and bronchial inflammation, i.e a down–regulating effect on the nuclear factorKB (NFKB). This hypothesis was tested on human endothelial cells and a human epithelial pulmonary cell line using different experimental methods. The results showed that CTZ down–regulates the TNF–α–induced hyperactivation of NFKB in these two different resident cells at physiological concentrations.
Cytotoxic Properties of Eosinophil Granule Major Basic Protein for Tumor Cells
Authors: Kubo Hirokazu , Loegering David A. , Adolphson Cheryl R. , Gleich Gerald J.
Published: April 2003

Background: Eosinophil granule major basic protein (MBP) mediates many eosinophil–associated immune functions and it adheres eosinophils to parasite targets. Methods: We compared the toxicities of MBP and melittin to K562 and HL–60 cells using five cytotoxicity methods. Results: Trypan blue staining, propidium iodide/ CellTracker™Green staining and incorporation of 14C–leucine assays indicated that MBP damages most cells by 1 h. In contrast, 51Cr and lactic dehydrogenase (LDH) release assays indicated that MBP damages most cells only at 20 h. All five methods indicated that melittin damages nearly all cells by 1 h. To resolve these discrepancies, the procedures were modified. Without cell transfer, dye staining methods showed that MBP produces very little cytotoxicity at 4 h. 51Cr and LDH assays, modified to mimic cell transfer, showed increased cytotoxicities at 4 h. The 14C–leucine assay modified by solubilization of cells with SDS and by trichloroacetic acid precipitation showed increased recovery of labeled protein and, thus, lower cytotoxicity, about 50%, at 4 h. Conclusion: Overall, MBP’s ability to cause molecular and cellular adhesion confounds cytotoxicity measurements. A modified 14C–leucine assay overcame MBP’s adhesiveness and provided an accurate measure of cytotoxicity.
Matrix Metalloproteinase–9 in Myeloid Cells: Implications for Allergic Inflammation
Authors: Hayashi Mitsutoshi , Schellenberg R. Robert , Tsang Samuel , Roberts Clive R.
Published: April 2003

Matrix metalloproteinase–9 (MMP–9; 92 kDa gelatinase) is utilized by myeloid and lymphoid cells for migration across basement membranes. Although eosinophils are commonly seen infiltrating asthmatic airways, the role of basophils in allergic inflammation is debated. This study was undertaken to evaluate the content of MMP–9 in purified basophils compared with eosinophils and neutrophils. Peripheral blood basophils were isolated to greater than 95% purity using negative selection with antibody–coated magnetic beads using a 12–antibody cocktail. Eosinophils of greater than 98% purity were obtained by negative selection and neutrophils by positive selection using anti–CD16 magnetic beads. MMP–9 activity was assessed by gelatin zymography of cell lysates. Under parallel conditions, neutrophils contained 1,000–fold more MMP–9 than eosinophils. No activity was detected from 2×105 basophils. Immunocytochemistry with an anti–MMP–9 antibody showed bright staining of all neutrophils, lesser staining of eosinophils and no detectable staining of basophils. The failure to find MMP–9 in basophils may explain their paucity in asthmatic airway inflammation or suggest they secrete other enzymes capable of degrading type IV collagen.
IL–4 Inhibits Human CD8 T Cell Expression of the Common IL–2 Receptor Gamma Chain
Authors: Vyas B. , Vukmanovic-Stejic M. , Noble A. , Kemeny D.M.
Published: April 2003

Previous studies in both rats and humans have shown that interleukin (IL) 4 can suppress the generation of IL–2–producing CD8 T cells. In an attempt to elucidate the mechanism by which this suppression is brought about, we set out to investigate whether the IL–4 signal interferes with the IL–2 receptor system. It has already been reported that IL–2 can affect the expression of its own receptor and thus provide a means of controlling its own activities. In this study, we demonstrate that the IL–2 Rα– and the IL–2 Rγ–chains are dramatically upregulated following stimulation of CD8 T cells, whereas lower levels of β–chain are observed. IL–4 did not affect the expression of the α– or β–chains, but was found to inhibit the generation of common γ–chain–expressing cells. Moreover, CD4 T cells were found to express much lower levels of this subunit and appeared less sensitive to the effects of IL–4. We postulate that the differential expression of the γ–chain subunit, in the presence and absence of IL–4, may provide a tool for identifying functionally distinct subpopulations of CD8 T cells.
Differences between Cytokine Release from Bronchial Epithelial Cells of Asthmatic Patients and Non–Asthmatic Subjects: Effect of Exposure to Diesel Exhaust Particles
Authors: Devalia J.L. , Bayram H. , Abdelaziz M.M. , Sapsford R.J. , Davies R.J.
Published: April 2003

Background: Recent evidence suggests that the airways of asthmatics are more susceptible to adverse effects of air pollutants than the airways of non–asthmatics, but the underlying mechanisms are not clear. Methods: We have cultured bronchial epithelial cells (HBEC) from biopsies of atopic mild asthmatic patients and non–atopic non–asthmatic subjects, and investigated constitutive and diesel exhaust particles (DEP)–induced release of several pro–inflammatory mediators. Results: HBEC of asthmatic patients constitutively released significantly greater amounts of IL–8, GM–CSF and sICAM–1 than HBEC of non–asthmatic subjects. RANTES was only released by HBEC of asthmatic patients. Incubation of the asthmatic cultures with 10 μg/ml DEP significantly increased the release of IL–8, GM–CSF and sICAM–1 after 24 h. In contrast, only the higher concentrations of 50–100 μg/ml DEP significantly increased the release of IL–8 and GM–CSF from HBEC of non–asthmatics. Conclusions: These results suggest that the increased sensitivity of the airways of asthmatics to air pollutants such as DEP may, at least in part, be a consequence of greater constitutive and pollutant–induced release of specific pro–inflammatory mediators from their bronchial epithelial cells.
Regulation of FcÂRI Synthesis in Human Eosinophils
Authors: Bjerke Torbjørn , Hoffmann Hans Jürgen , Christensen Erik Ilsøe , Poulsen Lars Kaergaard , Skjold Tina , Dahl Ronald
Published: April 2003

FcεRI, the high–affinity receptor for IgE, and eosinophils are thought to be key components of the allergic reaction underlying asthma and rhinitis. We provide evidence at the protein level that FcεRI is expressed in human blood eosinophils, and that the synthesis of FcεRI in purified human blood eosinophils is regulated by fibronectin in combination with IgE, IL–4, both involved in allergic reactions, and by RANTES, a strong chemotactic agent for eosinophils. This provides further evidence for a regulatory effect of IgE on human eosinophils in allergic disease.
Signal Transduction through Interferon–Gamma Receptor on Human Eosinophils
Authors: Ochiai K. , Ishihara C. , Tomioka H.
Published: April 2003

Background: We reported on the constitutive interferon–γ receptor (IFN–γR) expression on eosinophils. But signal transduction through IFN–γR on eosinophils remains to be elucidated. In this study, we examined the involvement of the Jak/Stat pathway in the signaling of eosinophils after IFN–γR conjugation by the ligand binding. Methods: Purified peripheral eosinophils were stimulated with IFN–γ at 37°C for 1–60 min. Tyrosine phosphorylation of IFN–γR, Jak1, Jak2, and Stat1α was examined by immunoblotting. Gel–shift assay was also examined to show the formation of Stat1α–DNA complexes. Results: We show that binding of IFN–γ to human eosinophils initiated a series of events that resulted in the rapid tyrosine phosphorylation of not only the IFN–γRα chain but also Jak1, Jak2, and Stat1α. In addition, IFN–γ enhanced the DNA–binding activity of Stat1α. Conclusion: These data indicate that IFN–γ affects eosinophils through its specific receptor and utilizes the Jak/Stat pathway as its mode of signaling.
DNA–Based Immunization for Asthma
Authors: Broide David , Raz Eyal
Published: April 2003

Background: Immunostimulatory DNA sequences (ISS) containing a CpG motif are able to inhibit Th2–mediated airway eosinophilia and bronchial hyperresponsiveness in a mouse model of asthma. Methods: To determine the optimal frequency and timing of intervention with ISS in inhibiting Th2 cytokine production and airway eosinophilia, we used ISS administration protocols which differed in the frequency (one vs. two doses), route (systemic vs. mucosal) and timing of ISS administration (before or together with antigen) in a mouse model of ovalbumin–induced eosinophilic airway inflammation. Results: ISS induced Th1 cytokine production (IFN–γ) and effectively inhibited Th2 cytokine production (IL–5) as well as eosinophilic inflammation when ISS was administered before or coadministered with inhaled allergen challenge. Although ISS was effective when coadministered with inhaled allergen, it was most effective when administered once 6 days prior to allergen challenge. Mucosal (intranasal and intratracheal) delivery of ISS was as effective as systemic (intraperitoneal) ISS delivery in inhibiting airway eosinophilia and switching cytokine responses from a Th2 to a Th1 response. Conclusions: ISS is most effective in inhibiting airway eosinophilia when administered as a single dose 6 days prior to antigen inhalation. However, ISS can also significantly inhibit eosinophilic inflammation, when coadministered with antigen inhalation. Thus, ISS administered prior or together with allergen should be considered as a novel method of allergen–based immunotherapy.
Soluble Human Interleukin–4 Receptor Is Produced by Activated T Cells under the Control of Metalloproteinases
Authors: Jung Thomas , Schrader Nicole , Hellwig Michaela , Enssle Karl Heinz , Neumann Christine
Published: April 2003

Background: Soluble interleukin 4 receptors (sIL–4R) are present in biological fluids. In contrast to mice, in man no distinct mRNA coding for sIL–4R has been described, suggesting that human sIL–4R is exclusively produced by proteolytic cleavage of the cell surface receptor. It is not known whether human sIL–4R is actively produced during an immune response. Methods: Human purified T cells, CD4+, CD8+, CD45RA+ and CD45R0+ T cell subpopulations were activated in vitro. sIL–4R was determined in the supernatants, cell surface IL–4R was measured by flow cytometry and RT–PCR. Results: Recombinant sIL–4R inhibited IL–4–mediated proliferation and IL–5 upregulation by T cells. sIL–4R could be detected at low levels in supernatants of nonactivated T cells, but at high levels following TCR engagement. This response was paralleled by enhanced transcription and de novo synthesis of the human cell surface IL–4R. Both, activated naive CD45RA+ and memory CD45R0+ T cells, produced sIL–4R with long–lasting kinetics. IL–4 increased sIL–4R production by activated CD45RA+, but there was less of an increase by CD45R0+ T cells. In addition, interferon–γ enhanced sIL–4R production. Cycloheximide and dexamethasone inhibited sIL–4R production by activated T cells, but did not abolish constitutive release of sIL–4R. Phosphoramidon and 1,10–phenanthroline dose–dependently inhibited shedding of the IL–4R, even in nonactivated T cells. Conclusion: The production of human sIL–4R by T cells is regulated by TCR stimuli, IL–4 and IFN–γ and needs the activity of metalloproteinases. Thus, sIL–4R should be regarded as inducible and due to its IL–4–antagonizing activity an immunoregulatory molecule.
Chronic Idiopathic Urticaria: Natural Course and Association with Helicobacter pylori Infection
Authors: Schnyder Benno , Helbling Arthur , Pichler Werner J.
Published: April 2003

Background: Chronic urticaria is a common disease, though only few data on its natural course are available. In most cases the cause cannot be determined. Recently a relationship of chronic urticaria to infection with Helicobacter pylori (HP) has been postulated, but no controlled study has been performed to prove this association. Methods: In this prospective study the clinical course and rate of HP infection in 46 patients with chronic ‘idiopathic’ urticaria were investigated. Infected patients were treated in a double–blind placebo–controlled crossover study with amoxycillin and lansoprazol. Eradication and clinical course were followed up 2 months after each treatment, respectively, 3 and 6 months after the first consultation. Results: In 19/46 (41%) the chronic ‘idiopathic’ urticaria resolved within 6 months. 12 patients (24%) were infected with HP, which corresponds to the infection rate of the population at comparable ages without urticaria in Switzerland. Eradication of HP was achieved in 3, but only in 1 was the eradication associated with the resolution of urticaria. Conclusions: Our data show that in young patients with a rather short history of chronic urticaria frequently a rather favourable natural course of chronic idiopathic urticaria can be seen. No association between HP infection and chronic urticaria could be demonstrated.
Identification of the Soybean Hull Allergens Responsible for the Barcelona Asthma Outbreaks
Authors: Codina Rosa , Lockey Richard F. , Fernández-Caldas Enrique , Rama Ramón
Published: April 2003

Background: Soybean hulls were identified as the etiologic agent responsible for the asthma outbreaks that occurred in Barcelona and Cartagena, Spain. Objective: To identify the main soybean hull allergens using the sera of 18 asthmatic epidemic patients from Barcelona and to compare the results to those previously reported. Methods: Specific IgE to a soybean hull allergen extract was determined by radioimmunoassay and by sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) in a 10–20% Tris–tricine gradient gel followed by Western blot. Results: Specific IgE, which was detected in 15 of the 18 (83.3%) sera, indicated two nonoverlapping band patterns on the SDS–PAGE/Western blot: (1) pattern 1, present in 11 sera, consisted of three bands with estimated molecular weights (MWs) of 8, 7.5 and 7 kD, which are the MWs described for the allergens Gly m 2, Gly m 1A and Gly m 1B, respectively, and (2) pattern 2, present in 3 sera, consisted of a band with an estimated MW of 8.2–8.3 kD and four additional bands in a MW range of 25–36 kD. The remaining positive sera indicated very faint bands. Conclusions: This study confirms that soybean hulls contain three main allergens with MWs of 8, 7.5 and 7 kD, and indicates additional higher MW allergens, which selectively bind specific IgE of the sera that do not react with the three low MW components. This dichotomous and nonoverlapping pattern of allergen recognition has not been previously described.
Genetically Engineered Plant Allergens with Reduced Anaphylactic Activity
Authors: Singh Mohan B. , de Weerd Nicole , Bhalla Prem L.
Published: April 2003

Allergy immunotherapy is based on the administration of increasing amounts of the disease–eliciting allergens in order to yield allergen–specific non–responsiveness. Success of this therapy is associated with modulation of the immune response to allergenic molecules at the level of T–helper cells and the induction of blocking antibodies. The extracts used for immunotherapy are highly heterogenous preparations from natural sources and contain additional components, mostly proteins which are not well defined. Recombinant DNA technology offers novel tools for production of pure and well–characterised allergens for specific immunotherapy. However, high IgE reactivity of pure recombinant allergens is associated with an increased risk of potentially life–threatening anaphylactic reactions. A major improvement in allergen–specific immunotherapy may be achieved by using genetically engineered recombinant allergens with reduced anaphylactic activity. Recently the site– directed mutagenesis technique has been applied successfully to produce variants of major grass, birch and oilseed rape allergens with reduced IgE reactivity but retained T–cell reactivity. These modified allergens with reduced anaphylactic potential are novel candidates for safer and more effective allergen–specific immunotherapy.
Activation of Fc Epsilon RI Inhibits the Pyruvate Kinase through Direct Interaction with the Gamma–Chain
Authors: Oak Min–Ho , Cheong Ho , Kim Kyeong–Man
Published: April 2003

The downstream signaling components of high–affinity IgE receptor (FcεRI) were studied using yeast two–hybrid screening of the cDNA library constructed from RBL–2H3 cells. The cytoplasmic part of the γ–chain but not that of the β–chain was found to interact with pyruvate kinase in the yeast. The in–vitro–translated pyruvate kinase also specifically interacted with the bacterially expressed glutathione–S transferase fusion protein of the cytoplasmic part of the γ–chain. When RBL–2H3 cells were challenged with antigen, the activity of pyruvate kinase gradually decreased, reaching the minimum activity around 5 min after the activation, and then slowly returned to the normal level. The dose–response curve (antigen vs. pyruvate kinase activity) plotted at 5 min after stimulation showed that the pyruvate kinase was dose–dependently inhibited and the maximum inhibition was reached at the concentration of 0.1 μg/ml of antigen. Direct interaction between FcεRI and pyruvate kinase was also demonstrated by co–immunoprecipitation in RBL–2H3 cells. These data suggest that pyruvate kinase is functionally linked with FcεRI and might exert an important role in controlling cellular functions following the activation of FcεRI.
Expression of B7–1, B7–2, and Interleukin–12 in Anti–Fas Antibody–Induced Pulmonary Fibrosis in Mice
Authors: Kuwano Kazuyoshi , Kaneko Yumi , Hagimoto Naoki , Kawasaki Masayuki , Kunitake Ritsuko , Tanaka Takuo , Maeyama Takashige , Miyazaki Hiroyuki , Matsuba Tokuji , Hara Nobuyuki
Published: April 2003

Background: We have previously reported that the inhalation of anti–Fas antibody induced pulmonary fibrosis in mice. To induce an effective immune response, antigen–presenting cells have to not only present antigenic peptide with MHC molecules to T lymphocytes, but also express B7 costimulating molecules. The purpose of this study is to investigate whether B7 family costimulating molecules and interleukin–12 (IL–12), which primarily promote cellular immunity, are associated with anti–Fas antibody–induced pulmonary fibrosis. Methods: We examined the expression of B7–1, B7–2, and IL–12 using the revese transcription–polymerase chain reaction (RT–PCR), RT–in situ PCR, and immunohistochemistry. Results: We observed the upregulation of B7–1, B7–2, and IL–12 p40 mRNA after anti–Fas antibody inhalation. B7–2 and IL–12 p40 mRNA appeared to be expressed in mononuclear cells, while B7–1 mRNA and protein were expressed in bronchiolar epithelial cells as well as macrophages. Conclusion: These findings indicate that the T–cell–mediated immune response in this model involved the upregulation of B7–1, B7–2, and IL–12, and that the aberrant expression of B7–1 in bronchiolar epithelial cells may induce autoreactive T cell proliferation against themselves.
Phenotype of IL–16–Producing Cells in Bronchial Mucosa: Evidence for the Human Eosinophil and Mast Cell as Cellular Sources of IL–16 in Asthma
Authors: Laberge Sophie , Pinsonneault Stéphane , Ernst Pierre , Olivenstein Ronald , Ghaffar Omar , Center David M. , Hamid Qutayba
Published: April 2003

Background: We have previously shown increased expression of the CD4+ cell chemoattractant interleukin (IL)–16 in bronchial biopsies of atopic asthmatic subjects compared to normal controls. IL–16 immunoreactive cells were identified as both epithelial cells and non–epithelial inflammatory cells. The aim of this study was to characterize and compare the phenotype of non–epithelial inflammatory cells that express IL–16 immunoreactivity in bronchial biopsies from non–atopic normal controls and atopic asthmatic subjects. Methods:  Sections from endobronchial biopsies obtained from non–atopic normal controls and atopic asthmatics were processed for double immunocytochemistry. IL–16 immunoreactivity was assessed using a polyclonal anti–IL–16 antibody and the avidin–biotin complex–diaminobenzidine method. The phenotype of IL–16 immunoreactive cells was assessed using anti–CD3, anti–MBP, anti–tryptase and anti–CD68 mAbs and the alkaline phosphatase complex–Fast Red method. Results: In normal subjects, the majority of IL–16 immunoreactive cells were CD3+ T cells (71.1±10.3%) and CD68+ macrophages (22.4±8.1%). IL–16 immunoreactivity coexpressed with tryptase+ mast cells in 4 of 7 normal subjects whereas IL–16 immunoreactivity coexpressed with MBP+ eosinophils in only 1 normal subject. In atopic asthmatic subjects, IL–16 immunoreactive cells were mainly CD3+ T cells (60.8±8.7%) and MPB+ eosinophils (16.8±8.2%). IL–16 immunoreactivity also coexpressed with tryptase+ mast cells (10.6±4.0%) in all asthmatic subjects. The number of IL–16 immunoreactive cells that coexpressed MBP was higher in asthmatic subjects compared to normal controls (p = 0.003). Conclusion: Our data show that T cells are the major non–epithelial cellular source of IL–16 in normal and asthmatic airways. Eosinophils and mast cells comprised other potential cellular sources of IL–16 in asthmatic airways.
Soluble Intercellular Adhesion Molecule–1 in Sera of Children with Bronchial Asthma Exacerbation
Authors: El-Sawy Ihab H. , Badr-El-Din Omneya M. , El-Azzouni Omar E. , Motawae Hanan A.
Published: April 2003

Previous studies have suggested that intercellular adhesion molecule–1 (ICAM–1; CD54) may be involved in the pathogenesis of asthma. In addition, a soluble form of intercellular adhesion molecule–1 (sICAM–1) has been detected in increased concentrations in the sera from adult patients with certain inflammatory, immune, or malignant diseases. To determine whether bronchial asthma exacerbation in children is associated with increased levels of serum sICAM–1 and to investigate the effect of the severity of exacerbation on these levels, the concentrations of sICAM–1 were measured in sera of 20 healthy control children and 45 asthmatic children (15 with mild, 15 with moderate, and 15 with severe asthma exacerbation) using an immunoenzymatic assay. Assessment of the severity of asthma exacerbation was based on clinical and physiological parameters. The mean (± SD) level of serum sICAM–1 for asthmatic children (390.0±108.3 ng/ml) was significantly higher than that for healthy (193.2±33.95 ng/ml; p = 0.000). We have also found a differential rise of serum sICAM–1 level which correlates well with the severity of asthma exacerbation. The elevated concentrations of serum sICAM–1 in acute bronchial asthma may reflect the extensive inflammatory response occurring in the airways during acute exacerbation of the disease with airway obstruction. The results of this study suggest that serum sICAM–1 is a promising serological marker of the severity of inflammation in bronchial asthma in children and it would not only facilitate staging of inflammation but also allow the monitoring of therapy and intervention.
High Levels of Olea europaea Pollen and Relation with Clinical Findings
Authors: Florido J. Fernando , Delgado P. Gonzalez , de San Pedro B. Saenz , Quiralte J. , de Saavedra J.M. Arias , Peralta V. , Valenzuela L. Ruiz
Published: April 2003

Background: Olea europaea pollen is an important cause of seasonal allergic rhinitis and bronchial asthma in southern Spain. For patients allergic to grass pol– len the critical concentration of airborn pollen is 50 grains/m3, but in the case of Olea pollinosis no data is available. Methods: Fifty–six seasonal allergic rhinitis patients (29 in 1994 and 27 in 1995) were included in this study, all of whom lived in Jaen. Daily symptom card were filled in and pollen counts during May and June were performed in both years. A linear regression model was used for analysis of the airborne pollen concentration and the symptom score. Results: Significant correlations among daily counts of Olea pollen and rhinitis symptoms were obtained. Most of our monosensitized patients needed a high Olea pollen concentration in the atmosphere (around 400 grains/m3) to suffer at least from mild allergic rhinitis symptoms. Conclusion: Local conditions with a wide area dedicated to olive tree cultivars result in a high concentration of this pollen in the atmosphere. Monosensitized Olea patients in our area seem to need exceptionally high levels to suffer from allergic symptoms.
Peanut–Induced Anaphylactic Reactions
Authors: Burks Wesley , Bannon Gary A. , Sicherer Scott , Sampson Hugh A.
Published: April 2003

Food allergies, particularly to peanuts, are a common cause of anaphylaxis. Approximately 125 people die each year in the USA secondary to food–induced anaphylaxis. Clinical anaphylaxis is a syndrome of diverse etiology and dramatic presentation of symptoms associated with the classic features of type I, IgE–mediated hypersensitivity [1]. Typically the term anaphylaxis connotes an immunologically–mediated event that occurs after exposure to certain foreign substances. This reaction results from the generation and release of a variety of potent biologically active mediators and their concerted effects on various target organs. Anaphylaxis is recognized by cutaneous, respiratory, cardiovascular, and gastrointestinal signs and symptoms occurring singly or in combination. This article focuses on allergic reactions to peanuts that manifest as signs and symptoms involving multiple target organs or the cardiovascular system alone.
Structural and Ligand Binding Analysis of Recombinant Blo t 13 Allergen from Blomia tropicalis Mite, a Fatty Acid Binding Protein
Authors: Puerta Leonardo , Kennedy Malcolm W. , Jiménez Silvia , Caraballo Luis
Published: April 2003

Background: We have previously described a cDNA (clone Bt6) encoding a novel allergen from Blomia tropicalis, which showed sequence similarities to the FABP/P2/cellular retinoic acid binding protein/cellular retinol binding protein, a family of cytosolic lipid transport proteins (cLTPs). This work was planned to better characterize this allergen to which the official name Blo t 13 had been assigned. Methods: Fluorescence–based lipid ligand binding assays and secondary structure analysis by circular dicroism were carry out using recombinant Blo t 13 (rBlo t 13) protein. Structural predictions and molecular modelling were performed based on the amino acid sequence inferred from the open reading frame of Bt6 cDNA sequence. Results: rBlot t 13 binds the natural fluorescent fatty acid cis–parinaric acid and oleic acid by competition, but not retinol, retinoic acid, cholesterol, dansylated or anthroxylated fatty acids such as dansyl–DL–aminocaprylic acid and 12–(9–anthroyloxy)–stereate. Circular dichroism analysis indicated that rBlo t 13 comprises 45% β–sheet and 13% α–helix. The amino acid sequence of Blo t 13 modelled well to known crystal structures of cLTPs providing a tertiary structural model comprising ten β–strands organized into two β–sheets, and two short α–helices. Conclusion: Blo t 13 is a fatty acid–specific member of the β–rich cLTP family of proteins.
Pertussis Adjuvant Prolongs Intestinal Hypersensitivity
Authors: Kosecka U. , Berin M.C. , Perdue M.H.
Published: April 2003

Background: Immediate hypersensitivity reactions are a hallmark of allergic disease, and result in the clinical features of food allergy, hayfever, and atopic asthma. The mechanism by which an individual becomes sensitized to an ingested or airborne allergen is not clear, however exposure to bacteria or bacterial products that act as adjuvants may be a contributing factor. The purpose of this study was to examine the role of pertussis toxin (PT) in inducing intestinal hypersensitivity reactions, particularly the ability of the adjuvant to prolong the sensitization. Methods: Rats were sensitized to ovalbumin (OA) by injection of OA alone or with 50 ng PT. Secretory responses to OA challenge and nerve stimulation were assessed in jejunal tissues mounted in Ussing chambers. Results: Jejunal segments from rats sensitized to OA alone responded to antigen challenge with ion secretion, but sensitization was transient in that specific IgE titers and responses to luminal antigen disappeared by 14 days. In contrast, co–administration of 50 ng PT with OA resulted in long–lasting sensitization. Secretory responses to both luminal and serosal OA challenge were present 8 months after primary immunization. Enhanced secretory responses to nerve stimulation, increased mucosal mast cell numbers, as well as elevated IgE titers were also induced and may have contributed to the overall responsiveness of the intestine to antigen challenge. Conclusions: Our findings indicate nanogram quantities of PT, when administered with a food protein, result in long–term sensitization to the antigen, and altered intestinal neuroimmune function. These data suggest that exposure to bacterial pathogens may prolong the normally transient immune responsiveness to inert food antigens.
Pathophysiological Features of the Nasal Mucosa in Patients with Idiopathic Rhinitis Compared to Allergic Rhinitis
Authors: Numata Tsutomu , Konno Akiyoshi , Hasegawa Shinya , Hanazawa Toyoyuki , Nagata Hiroshi , Motosugi Hideaki , Terada Nobuhisa
Published: April 2003

Background: The literature on abnormality of vasomotor responses of the nasal mucosa to cold stimulation of the skin in idiopathic rhinitis is conflicting. The objective of this study was to elucidate pathophysiological features of the nasal mucosa in idiopathic rhinitis compared to allergic rhinitis. Methods: The following were studied in patients with idiopathic rhinitis and allergic rhinitis and in normal controls: (1) threshold of the nasal reaction to histamine; (2) inflammatory cells in nasal lavage and scraped nasal mucosal epithelium, and (3) nasal vasomotor response to cold stimulation of the feet evaluated by acoustic rhinometry. Results: Inflammatory cells were not found to be involved in idiopathic rhinitis. Nasal reactivity to histamine was significantly enhanced in patients with idiopathic rhinitis compared to normal controls, but was significantly lower compared to those with allergic rhinitis. The most prominent finding in idiopathic rhinitis was nasal mucosal swelling induced by cold stimulation of the feet. While in normal controls, cold stimulation of the feet caused mucosal contraction due to sympathetic excitation, sympathetic nasal vasomotor response in idiopathic rhinitis patients was significantly inhibited and caused mucosal swelling and enhanced nasal secretion. Mucosal reactions observed in allergic rhinitis were between those observed in idiopathic rhinitis and in normal controls. Cold stimulation of the feet increased systolic blood pressure by 5–15 mm Hg, but the degree of increase observed in the 3 groups was almost equal. Conclusions: The above findings indicate that patients with idiopathic rhinitis have abnormalities that inhibit sympathetic reactions and enhance parasympathetic vasomotor response at peripheral levels, possibly in the nasal mucosa.
Role of IL–5 in the Development of Allergen–Induced Airway Hyperresponsiveness
Authors: Hamelmann Eckard , Gelfand Erwin W.
Published: April 2003

This review evaluates the role of IL–5 and IL–5–mediated eosinophil airway infiltration in the development of allergen–driven airway hyperresponsiveness. It discusses the structure and function of IL–5 and its receptor and the mechanisms of IL–5–triggered eosinophil accumulation and inflammation of the airways. New research data from murine models of airway inflammation and hyperresponsiveness utilizing different modes of sensitization to allergen and anti–IL–5 antibody or IL–5–deficient knock–out mice underscore the outstanding role of this cytokine in the pathogenesis of bronchial asthma. This review identifies possible directions for future treatment of airway hyperresponsiveness and concludes that targeting IL–5–driven inflammatory responses may be most beneficial for a novel therapy in bronchial asthma.