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C J Sanderson

Publications and source records attributed to C J Sanderson.

At least 37 records · Page 2Linked to original sources
PubMed1998

Biological and molecular characteristics of interleukin-5 and its receptor.

Interleukin-5 (IL5) is a T cell-derived cytokine involved in the pathogenesis of atopic diseases. It specifically controls the production, the activation and the localization of Eosinophils. The Eosinophils are the major cause of tissue damage resulting in the symptoms of asthma and related allergic disorders. T cells purified from bronchoalveolar lavage and peripheral blood of asthmatics secrete elevated amount of IL5. Therefore IL5 emerges to be an attractive target for the generation of new anti-allergic drugs. Agents which inhibit either the production or the activity of IL5 could be expected to ameliorate the pathological effects of the allergic response. A better understanding of the biology of IL5 and the regulation of its expression is, however, a prerequisite for the development of new therapeutic agents. This review covers the major biological, molecular and structural aspects of IL5 research since the identification of this cytokine ten years ago.

Eosinophils↗
PubMed1998

New directions in understanding interleukin-5 gene expression.

Specific regulation of the interleukin-5 (IL-5) gene is implied by the unique control of eosinophilia which is regulated by IL-5. In studies of IL-5 gene expression, the only control elements identified for the IL-5 gene have been transcriptional elements in the 5' untranslated region (UTR). Significant differences exist in the arrangement of the murine and human IL-5 promoters, which is surprising considering the tight regulation of the gene. Novel palindromic regulatory elements involved in transcriptional regulation have been found in the 5' UTR and new results show the presence of transcriptional elements in the 3' UTR. Post-transcriptional control mechanisms in both the 5' and 3' UTRs have also been described.

Animals↗
PubMed1997

Eosinophilic interleukin 5 (IL-5) transgenic mice: eosinophil activity and impaired clearance of Schistosoma mansoni.

Eosinophilia is a feature common to many invasive helminth infections and eosinophils are often considered to be effector cells in immunity to helminths. This study examined the possible influence of constitutive eosinophilia on the clearance of Schistosoma mansoni infections in mice. Eosinophils from interleukin-5 transgenic mice exhibit normal ultrastructure and function with regard to phagocytosis and killing of bacteria and responses to chemotactic stimuli. IL-5 transgenics and non-transgenic littermates were immunized once or four (hyperimmunization) times with irradiated cercariae of S. mansoni. Animals were challenged percutaneously with unirradiated cercariae one month after their last exposure to irradiated parasites. One month after challenge transgenic animals, whether unimmunized, vaccinated or hypervaccinated, carried significantly more liver-stage parasites than non-transgenic animals. These results suggest that although eosinophils from IL-5 transgenic mice are functional for a number of key parameters, large numbers of eosinophils and/or high levels of IL-5 may in some way impair clearance of S. mansoni. A re-evaluation of the roles of eosinophils and IL-5 in infections with this and other parasites may therefore be warranted.

Animals↗
PubMed1997

Anti-interleukin 5 strategies as a potential treatment for asthma.

A paradigm shift, championed largely by cellular immunologists, has redefined asthma as an immune mediated phenomenon characterised by an interleukin 5 (IL-5) driven eosinophilic bronchitis. This change in emphasis has provoked intense interest in the possibility that inhibitors of IL-5 production, or antagonists of its activity, will provide a new generation of anti-asthma drugs.

Asthma↗
PubMed1996

Two pathways can activate the interleukin-5 gene and induce binding to the conserved lymphokine element 0.

Eosinophilia is a uniquely specific phenomenon regulated by interleukin-5 (IL-5), suggesting specific control for IL-5 gene expression. Using a transient-transfection reporter assay and DNA mobility-shift experiments in EL4 mouse lymphoma cells, reporter expression and binding of transcription factors to the conserved lymphokine element 0 (CLE0) in the mouse (mIL-5) promoter was investigated. Activation of the IL-5 promoter required costimulation of T cells with phorbol ester (phorbol 12-myristate 13-acetate [PMA]) and cyclic adenosine 3',5'-monophosphate (cAMP), but was blocked by the immunosuppressive drug, cyclosporin A (CsA). Binding to CLE0 was induced under conditions optimal for IL-5 transcription but was not blocked by CsA. CD28-induced signals could partly substitute for cAMP. However, the effects of cAMP, but not of CD28, were sensitive to the cAMP-dependent protein kinase inhibitor, H89, suggesting that CD28 does not involve a cAMP mechanism. It therefore appears that IL-5 expression can be induced by at least two distinct stimulatory pathways. Although CLE0 contains sequences similar to AP-1 and NF-AT, only the AP-1 moiety of the CLE0 element could be demonstrated to have inducible binding. Experiments with antisera to the AP-1 family of transcription factors indicated that c-fos and JunB bind to the IL-5 CLE0 in activated lymphoma cells. The role of the NF-AT-like element was less clear. A constitutively expressed protein showed a weak band that was inhibited by mIL-2 NF-AT competitor sequences. However, this protein did not react with an anti-NF-ATp antiserum. On the other hand, transcription was partially inhibited by an oligonucleotide containing the intact NF-AT-like element from CLE0, suggesting that the element is important for optimal transcription, but the nature of the protein binding to it remains unknown. The fact that these factors are induced in a subclone of EL4 that does not express IL-5 and bind to a number of other cytokine gene promoters suggests that although binding to CLE0 appears to be necessary for IL-5 transcription, other factors must control the specific expression of the gene.

Animals↗
PubMed1996

How is expression of the interleukin-5 gene regulated?

Eosinophilia is a uniquely specific phenomenon regulated by interleukin-5 (IL-5), suggesting specific control for IL-5 expression. However in eosinophilia IL-5 is often co-expressed with other lymphokines such as IL-4, indicating that common, as well as independent, control mechanisms must exist. IL-5 gene expression is regulated at the transcriptional level. The molecular analysis of the IL-5 promoter region reveals the presence of positive regulatory sites that are common to many lymphokine genes. Results from immunosuppression studies suggest that the key control mechanism of IL-5 regulation may not depend on specific regulatory factors but on how gene expression is activated.

Animals↗
PubMed1996

Diagnostic criteria for selenium toxicosis in aquatic birds: dietary exposure, tissue concentrations, and macroscopic effects.

A feeding study with mallard ducks (Anas platyrhynchos) was conducted during March to July 1988 in Laurel, Maryland (USA), to identify diagnostic criteria for selenium toxicosis in birds. One-year-old male mallards in groups of 21 were fed diets containing 0, 10, 20, 40, or 80 parts per million (ppm) selenium, as seleno-DL-methionine, for 16 weeks. All ducks receiving 80 ppm died. Ducks receiving 40 or 80 ppm selenium consumed less feed than ducks in the other treatment groups. Body weights of ducks receiving 40 or 80 ppm selenium declined during the study. The post-breeding molt was delayed in ducks receiving 40 ppm; most ducks receiving 80 ppm selenium died prior to the onset of molt. At necropsy, numerous abnormalities were observed in ducks that died but only a small number of abnormalities were observed in ducks surviving to the end of the study in the 40 ppm group. Weights of the heart, spleen, and pancreas were mostly lower and weights of the kidney were higher for ducks dying during the study than for euthanized ducks. Liver weights were unaffected. Selenium accumulated in soft tissues approximately in proportion to dietary concentrations. Selenium concentrations in tissues of all ducks that died were different from those of surviving ducks in the 0, 10, and 20 ppm groups, but were not different from those of surviving ducks in the 40 ppm group. Proposed diagnostic criteria for fatal chronic selenosis were derived from body weight, macroscopic abnormalities, organ weights, and concentrations of selenium in the liver. Proposed diagnostic criteria for non-fatal chronic selenosis were derived from body weight, plumage condition, macroscopic abnormalities, concentrations of selenium in the liver, reproductive failure, and alterations of blood and tissue chemistries. Lead or dioxin poisoning have diagnostic criteria most similar to selenium toxicosis.

Administration, Oral↗
PubMed1995

Detailed analysis of the IL-5-IL-5R alpha interaction: characterization of crucial residues on the ligand and the receptor.

The receptor for interleukin-5 (IL-5) is composed of two different subunits. The IL-5 receptor alpha (IL-5R alpha) is required for ligand-specific binding while association with the beta-chain results in increased binding affinity. Murine IL-5 (mIL-5) has similar activity on human and murine cells, whereas human IL-5 (hIL-5) has marginal activity on murine cells. We found that the combined substitution of K84 and N108 on hIL-5 by their respective murine counterpart yields a molecule which is as potent as mIL-5 for growth stimulation of a murine cell line. Since the unidirectional species specificity is due only to the interaction with the IL-5R alpha subunit, we have used chimeric IL-5R alpha molecules to define regions of hIL-5R alpha involved in species-specific hIL-5 ligand binding. We found that this property is largely determined by the NH2-terminal module of hIL-5R alpha, and detailed analysis defined D56 and to a lesser extent E58 as important for binding. Moreover, two additional residues, D55 and Y57, were identified by alanine scanning mutagenesis within the same region. Based on the observed homology between the NH2-terminal module and the membrane proximal (WSXWS-containing) module of hIL-5R alpha we located this stretch of four amino acid residues (D55, D56, Y57 and E58) in the loop region that connects the C and D beta-strands on the proposed tertiary structure of the NH2-terminal module.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1993

Human interleukin-5 induces staphylococcal A Cowan 1 strain-activated human B cells to secrete IgM.

Studies on the role of human interleukin (IL)-5 in B cell growth and differentiation have yielded conflicting results. To clarify this issue, we studied the role of purified recombinant IL-5 on activated human B cells which were depleted of T cells and adherent cells. Human IL-5 augments IgM secretion, but not IgG or IgA secretion of purified human B cells activated with staphylococcal A Cowan 1 strain (SAC). However, the period of B cell activation with SAC is critical for the B cell to respond to IL-5. After 24 h of SAC activation, human B cells are responsive to the IL-5 signal, but with longer periods of activation, IL-5 responsiveness diminishes. This may explain some of the previous conflicting results. The IgM enhancement was not seen when B cells were activated with pokeweed mitogen. In addition, human recombinant IL-4 synergized with IL-5 in augmenting IgM secretion by SAC-activated B cells, while IL-5 synergized with IL-2 to augment IgM, IgG and IgA secretion by SAC-activated B cells. As the purified IL-5 was derived from a COS-1 cell supernatant, and COS-1 cells secrete IL-6, we examined whether a polyclonal IL-6 antibody blocked the IgM-enhancing activity of IL-5. IL-6 antibody did not block the IL-5 enhancement of IgM secretion, but a monoclonal antibody to IL-5 inhibited the human IL-5 activity on human B cells. These results demonstrate that human IL-5 augments IgM secretion of SAC-activated human B-cells. In addition, this lymphokine synergizes with IL-4 and IL-2 in supporting Ig secretion.

Antibodies, Monoclonal↗
PubMed1992

Release of granule proteins from eosinophils cultured with IL-5.

Eosinophils isolated from normal individuals were cultured in the presence of human rIL-5 (hrIL-5) for up to 14 days, and the effects of this exposure were determined. First, the hrIL-5-cultured eosinophils were activated and degranulated more readily than freshly isolated eosinophils. For example, eosinophils cultured for 7 days with hrIL-5 released 30 and 10% of granule eosinophil-derived neurotoxin (EDN) when exposed to Sepharose 4B beads coupled to secretory IgA and IgG, respectively, whereas freshly isolated eosinophils released only 19 and 4%, respectively, of their EDN in response to the same stimuli. Degranulation of hrIL-5-cultured eosinophils was not augmented by further exposure to hrIL-5, whereas degranulation of freshly isolated cells to secretory IgA and IgG beads was increased by exposure to hrIL-5. Second, eosinophils cultured with hrIL-5 had prolonged viability in vitro. For example, after four days of culture with 50 U/ml of hrIL-5, 86% of eosinophils were viable compared to 12% in medium alone. Third, hrIL-5-cultured eosinophils became hypodense, and electron microscopy showed that they contained granules with core and matrix lucency and with evidence of granule fusion. Fourth, hrIL-5-cultured eosinophils spontaneously lost 30 to 60% of their EDN, eosinophil cationic protein, and eosinophil peroxidase and about 50% of their eosinophil granule major basic protein content compared to freshly isolated eosinophils, and all four of the granule proteins were released into the culture medium. Fifth, detailed studies of eosinophils cultured in hrIL-5 showed that 89 +/- 10% of the starting quantity of EDN could be recovered at 7 days. Whereas 99 +/- 1% of the EDN at day 0 was cell associated, by 7 days 60 +/- 9% was in the cell supernatants. Thus, hrIL-5 activates eosinophils, increases their viability, decreases their density, and their content of granule proteins and causes release of the granule proteins into culture fluids. The striking loss of granule proteins during culture with hrIL-5 may be an important mechanism for deposition of these cationic toxins in various diseases where IL-5 plays a role.

Blood Proteins↗
PubMed1992

Comparison of Nissen total and Lind partial transabdominal fundoplication in the treatment of gastro-oesophageal reflux.

Fifty-two patients with gastro-oesophageal reflux disease refractory to medical treatment were randomized to undergo a Nissen total (360 degrees wrap) or Lind partial (300 degrees wrap) transabdominal fundoplication. Each group was comparable in number (26 patients), mean age (47 and 48 years) and sex distribution (eight women). Preoperative and postoperative assessment involved a modified Visick score, 22-h intraoesophageal pH monitoring, endoscopy and manometry. Follow-up was at 6 weeks and between 3 and 33 (mean 13) months. The prevalence of heartburn and regurgitation and the results of pH monitoring improved significantly after both operations (P less than 0.001). At early assessment eight previously asymptomatic patients (31 per cent) from the Nissen group and six (23 per cent) from the Lind group experienced difficulty swallowing. Ten patients (38 per cent) in each group complained of 'gas bloat'. Both complications had improved at late assessment in the majority of patients. No statistically significant advantage could be demonstrated for either operation.

Adult↗
PubMed1992

Interactive effects of selenium, methionine, and dietary protein on survival, growth, and physiology in mallard ducklings.

Concentrations of over 100 ppm (100 mg/kg) selenium (Se) have been found in aquatic food chains associated with irrigation drainwater. Both quantity and composition of dietary protein for wild ducklings may vary in selenium-contaminated environments. Day-old mallard (Anas platyrhynchos) ducklings received one of the following diets containing 22% protein: unsupplemented (controls), 15 ppm Se (as selenomethionine), 60 ppm Se, methionine supplemented, 15 ppm Se with methionine supplement, or 60 ppm Se with methionine supplement. In a second concurrent experiment the above sequence was repeated with a protein-restricted (11%) but isocaloric diet. In a third concurrent experiment all ducklings received 44% protein with 0, 15, or 60 ppm Se added. After 4 weeks, blood and tissue samples were collected for biochemical and histological examination. With 22% protein and 60 ppm Se in the diet, duckling survival and growth was reduced and histopathological lesions of the liver occurred. Antagonistic interactive effects occurred between supplementary methionine and Se, including complete to partial alleviation of the following Se effects by methionine: mortality, hepatic lesions, and altered glutathione and thiol status. With 11% protein, growth of controls was less than that with 22% protein, Se (60 ppm) caused 100% mortality, and methionine supplementation, although protective afforded less protection than it did with 22% protein. With 44% protein, ducklings experienced physiological stress, and Se was more toxic than with methionine-supplemented 22% protein. These findings suggest the potential for antagonistic effects of Se, methionine, and protein on duckling survival and physiology.

Analysis of Variance↗
PubMed1992

Interactive effects of arsenate, selenium, and dietary protein on survival, growth, and physiology in mallard ducklings.

High concentrations of arsenic (As) and selenium (Se) have been found in aquatic food chains associated with irrigation drainwater. Total biomass of invertebrates, a major source of protein for wild ducklings, may vary in environments that are contaminated with selenium. Day-old mallard (Anas platyrhynchos) ducklings received an untreated diet (controls) containing 22% protein or diets containing 15 ppm Se (as selenomethionine), 60 ppm Se, 200 ppm As (as sodium arsenate), 15 ppm Se with 200 ppm As, or 60 ppm Se with 200 ppm As. In a concurrent experiment, the same sequence was repeated with a protein-restricted (7%) but isocaloric diet. After 4 weeks, blood and tissue samples were collected for biochemical and histological examination. With 22% protein and 60 ppm Se in the diet, duckling survival and growth was reduced and livers had histopathological lesions. Arsenic alone caused some reduction in growth. Antagonistic interactive effects occurred between As and Se, including complete to partial alleviation of the following Se effects: mortality, impaired growth, hepatic lesions and lipid peroxidation, and altered glutathione and thiol status. With 7% protein, survival and growth of controls was less than that with 22% protein, Se (60 ppm) caused 100% mortality, and As (200 ppm) caused mortality, decreased growth, and liver histopathology. These findings suggest the potential for antagonistic effects of Se and As on duckling survival, growth, and physiology with adequate dietary protein but more severe toxicological effects when dietary protein is diminished.

Animals↗
PubMed1992

Interleukin-5.

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Amino Acid Sequence↗
PubMed1991

Production and purification of recombinant human interleukin-5 from yeast and baculovirus expression systems.

A cDNA for human interleukin-5 (hIL-5) was created from the hIL-5 gene using site-directed mutagenesis to splice out the introns in vitro. This cDNA was expressed in yeast and baculovirus systems, utilizing in both cases an in-frame fusion to the pre sequence of the alpha-mating-type factor to direct secretion. The highest level of production was achieved from Sf9 cells using a baculovirus vector in serum-containing medium (2.7 mg/l), whereas in serum-free medium ten times less hIL-5 was produced. In the yeast system much lower levels of hIL-5 were produced (12.5 micrograms/l). Recombinant hIL-5 was purified to homogeneity from serum-free baculovirus cultures. The rhIL-5 consisted of a 30-kDa homodimer linked by disulfide bridging. The purified recombinant protein had a specific activity on murine BCL1 cells of 1.5 x 10(4) U/mg, of 3 x 10(5) U/mg in the murine eosinophil differentiation factor assay, and 2.4 x 10(7) U/mg in a human peripheral eosinophil maintenance assay.

Baculoviridae↗