The role of cytokines in the accumulation of eosinophil granulocytes in inflamed tissue has been studied extensively during recent years, and these molecules have been found to participate throughout ...the whole process of eosinophil recruitment. Haematopoietic cytokines such as IL‐3, IL‐5 and GM‐CSF stimulate the proliferation and differentiation of eosinophils in the bone marrow, and the release of mature eosinophils from the bone marrow into the blood is probably promoted by IL‐5. Priming of eosinophils in the blood following, for example, allergen challenge is performed mainly by IL‐3, IL‐5 and GM‐CSF. An important step in the extravasation of eosinophils is their adhesion to the vascular endothelium. Adhesion molecules are upregulated by, e.g. IL‐1, IL‐4, TNF‐α and IFN‐γ and the same cytokines may also increase the affinity of adhesion molecules both on eosinophils and endothelial cells. Finally, a number of cytokines have been shown to act as eosinophil chemotactic factors, attracting the cells to the inflammatory focus in the tissue. Some of the most important eosinophil chemoattractant cytokines are IL‐5, IL‐8, RANTES, eotaxin, eotaxin‐2, eotaxin‐3, MCP‐3, MCP‐4 and TNF‐α. Th2 cells, mast cells and epithelial cells are important sources of proinflammatory cytokines, but in recent years, the eosinophils have also been recognized as cytokine‐producing and thereby immunoregulatory cells. The aim of this paper is to review the role of cytokines in the process of eosinophil recruitment in asthma, allergy and ulcerative colitis.
Abstract A series of cancer vaccines have been evaluated in clinical trials with encouraging results, but the demonstration of clinical benefit in confirmatory studies has so far proven to be ...difficult. The development of cancer vaccines is hampered by a range of issues particular to this field of research. On 12th March 2008, the Biotherapy Development Association convened a workshop to discuss issues faced by scientists and clinicians involved in the development of cancer vaccines. This paper is a review of the field, based on discussions held at the BDA workshop, and describes biological barriers encountered in generating effective immune responses to tumours, methodological obstacles encountered in the improvement of immunological monitoring which aims to improve inter-laboratory and inter-trial comparisons, challenges in clinical trial design and problems posed by the lack of specific regulation for cancer vaccines and the impact on their development. Ultimately, a number of general solutions are posed: (1) better patient selection, (2) use of multi-modal treatments that affect several aspects of the immune system at once, (3) a requirement for the development of good biomarkers to stratify patients for selection prior to trial and as surrogates for clinical response and (4) harmonisation of SOPs for immunological monitoring of clinical trials.
Fifty-seven patients with MAGE-3-positive measurable metastatic cancer, most of them with melanoma, were vaccinated with escalating doses of a recombinant MAGE-3 protein combined with a fixed dose of ...the immunological adjuvant SBAS-2, which contained MPL and QS21. The immunisation schedule included 4 intramuscular (i.m.) injections at 3-week intervals. Patients whose tumour stabilised or regressed after 4 vaccinations received 2 additional vaccinations at 6-week intervals. The vaccine was generally well tolerated. Among the 33 melanoma patients who were evaluable for tumour response, we observed 2 partial responses, 2 mixed responses and 1 stabilisation. Time to progression in these 5 patients varied from 4 to 29 months. In addition, a partial response lasting 10 months was observed in 1 of the 3 metastatic bladder cancer patients included. None of the tumour responses described above involved visceral metastases. Immunological responses to the vaccine will be reported separately.
Neutrophil migration and respiratory burst are the prerequisite for efficient first line defense against invading microorganisms. However, migration and respiratory burst can be compromised in adults ...and especially in newborn infants, where sustained neutrophil accumulation, uncontrolled burst and reduced scavenging of ROS might cause inadvertent tissue damage due to uncontrolled inflammation. The aim of this study was to investigate the modulatory effect of the chemoattractants formyl‐methionyl‐leucyl‐phenylalanine (fMLP) and IL‐8 on respiratory burst in neutrophils from term newborn infants and adults. Whole blood from the umbilical cord of 17 healthy term newborn infants delivered by caesarean section and from 17 healthy adults as reference was preincubated with fMLP or IL‐8 and stimulated with PMA or Escherichia coli bacteria. Respiratory burst was quantified by flow cytometry analysis of dihydrorhodamine 123 fluorescence. fMLP reduced the PMA‐induced respiratory burst of neutrophils from newborn infants and adults by 12% and 21%, respectively (P < 0.05). E. coli‐induced burst was also reduced by fMLP in neutrophils from newborn infants (10%; P < 0.01) and adults (6%; P < 0.05). No such changes were observed with IL‐8. Similar respiratory burst in response to single stimulus with PMA or E. coli was observed in both newborn infants and adults. fMLP reduced PMA‐ and E. coli‐induced respiratory burst of neutrophils in whole blood from term newborn infants as well as in adults. The reduced respiratory burst by fMLP might be a mechanism to reduce the detrimental effects of uncontrolled inflammation during neutrophil migration.
We have previously observed that neutrophils from neonates exhibit different migratory responses to intermediate and end‐target chemoattractants compared to adults. The aim of this study was to ...investigate the effect of the chemoattractants IL‐8 (intermediate) and formyl‐methionyl‐leucyl‐phenylalanine (fMLP; end‐target) on cell surface receptor expression involved in adhesion, migration and granule release of neutrophils from term newborn infants and adults. Heparinized cord blood from 16 healthy term newborn infants delivered by caesarean section and peripheral blood from 17 healthy adults were incubated with 1 μm IL‐8 or 0.1 μm fMLP, previously defined as optimal inducers of neutrophil migration. The leukocytes were labelled with antibodies to cell surface receptors (CD11b, CD15S, CD18, CD35, CD44, CD64, CD65, CD88, CD162, CD181 and CD182). Receptor expression was quantified by flow cytometry analysis. Upregulation of CD11b and downregulation of CD88 and CD182 after stimulation with IL‐8 were more pronounced in adults than in neonates (P < 0.05, P < 0.05 and P ≤ 0.001, respectively), whereas fMLP induced changes in receptor expression that were of the same magnitude in neutrophils from neonates as from adults. We observed similar expression of receptors that mediate adhesion, migration, granule activation and phagocytosis induced by fMLP in neutrophils from neonates and adults. In contrast, differences between neonates and adults, induced by IL‐8, suggest that the neutrophil response to intermediate chemoattractants might lead to a compromised infectious response in newborn infants.
This paper reports on a state-of-the-art remote laboratory project called Virtual Instrument Systems in Reality (VISIR). VISIR allows wiring and measuring of electronic circuits remotely on a virtual ...workbench that replicates physical circuit breadboards. The wiring mechanism is developed by means of a relay switching matrix connected to a PCI eXtensions for Instrumentation (PXI) instrumentation platform. The entire equipment is controlled by LabVIEW server software, in addition to a measurement server software that protects the equipment from hazard connections by verifying input circuit designs, sent by students, before being executed. This paper addresses other approaches such as remote labs based on Data Acquisition Cards (DAQs), NetLab, and RemotElectLab, comparing them with VISIR in order to emphasize its singularity. Topics discussed are as follows: the technical description, software, operation cycle, features, and provided services. In addition, the feedback received by students at several universities and the encountered drawbacks along with the proposed solutions are highlighted. The paper finally addresses the ongoing and future challenges within the VISIR community including its integration with Learning Management Systems (LMSs) and iLab Shared Architecture (ISA), its new hardware version release that is based on LAN eXtensions for Instrumentation (LXI), and its new open platform version that supports federated access.
We assessed the tolerability, safety, pharmacokinetics and dose-limiting toxicity (DLT) of the recombinant humanized IgG4 anti-vascular endothelial growth factor (VEGF) monoclonal antibody, HuMV833, ...in patients with advanced cancer. Cohorts of patients with progressive solid tumours received escalating doses of HuMV833 as a 1-h intravenous (I.V.) infusion on days 1, 15, 22, and 29. Twenty patients (median Eastern Cooperative Oncology Group (ECOG) score 1) were accrued. HuMV833 infusions were well tolerated and there were no grade III or IV toxicities definitely related to the antibody. Grade I or II toxicities probably related to the antibody included fatigue, dyspnoea and rash. There were two episodes of asymptomatic hypocalcaemia, one at grade III and one grade IV, which were recorded in early follow-up. There were eight grade I episodes of asymptomatic elevation of activated partial thromboplastin time (APTT) and two grade III events; one in a patient receiving 1
mg/kg and the other receiving extended doses of 10
mg/kg. Pharmacokinetic analysis revealed a non-linear kinetic and an elimination half-life of between 8.2 (0.3
mg/kg) and 18.7 (10
mg/kg) days. One patient with ovarian cancer experienced a partial response (PR) of 9
months duration and eight had disease stabilisation (SD) including one patient with colorectal carcinoma whose disease was stable for 14
months. In 13 of the 14 samples taken from 12 patients, the plasma concentration of hepatocyte growth factor (HGF) was reduced 24
h after drug administration. HuMV833 is safe and lacked DLT at doses up to 10
mg/kg on this schedule. Multiple doses were well tolerated, despite occasional asymptomatic elevations in APTT. By combining pharmacokinetic, pharmacodynamic and toxicity data, we can identify doses of 1 and 3
mg/kg for further investigation. HuMV833 appears to possess some clinical activity.
The adipose tissue-derived hormone leptin regulates body weight homeostasis by decreasing food intake and increasing energy expenditure. The weight-reducing action of leptin is thought to be mediated ...primarily by signal transduction through the leptin receptor (LR) in the hypothalamus. We have used immunohistochemistry to localize LR-immunoreactive (LR-IR) cells in the rat brain using an antiserum against a portion of the intracellular domain of LR that is common to all LR isoforms. The antiserum recognized the short and long isoforms of LR in transfected hematopoietic BaF3 cells. To examine the chemical nature of target cells for leptin, direct double-labeling immunofluorescence histochemistry was applied. The results show extensive distribution of LR-like immunoreactivity (LR-LI) in the brain with positively stained cells present, e.g., in the choroid plexus, cerebral cortex, hippocampus, thalamus, and hypothalamus. In the hypothalamus, strongly LR-IR neurons were present in the supraoptic nucleus (SON) and paraventricular nucleus (PVN), periventricular nucleus, arcuate nucleus, and lateral hypothalamus. Weaker LR-IR neurons were also demonstrated in the lateral and medial preoptic nuclei, suprachiasmatic nucleus, ventromedial and dorsomedial nuclei, and tuberomammillary nucleus. Confocal laser scanning microscopy showed LR-LI in the periphery of individual cells. In magnocellular neurons of the SON and PVN, LR-LI was demonstrated in vasopressin- and oxytocin-containing neurons. In parvocellular neurons of the PVN, LR-LI was demonstrated in many corticotropin-releasing hormone-containing neurons. LR-IR neurons were mainly seen in the ventromedial aspect of the arcuate nucleus, where LR-LI co-localized with neuropeptide Y. In the ventrolateral part of the arcuate nucleus, LR-LI was present in many large adrenocorticotropic hormone-IR proopiomelanocortin-containing neurons and in a few galanin-, neurotensin-, and growth hormone-releasing hormone-containing neurons. In the dorsomedial arcuate nucleus, few tyrosine hydroxylase (dopamine)-containing neurons were seen to have LR-LI. Melanin-concentrating hormone-containing neurons in the lateral hypothalamus had LR-LI. Based on the immunohistochemical results, possible interactions of leptin with brain mechanisms are discussed.
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