P4-13-01: Pain Severity and Analgesic Use Associated with Skeletal-Related Events in Patients with Advanced Breast Cancer and Bone Metastases

Background: Skeletal-related events (SREs), which include pathologic fracture (PF), radiation to bone (RB), surgery to bone (SB), and spinal cord compression (SCC), occur frequently in patients with bone metastases and can lead to debilitating clinical consequences such as functional impairment and bone pain. Denosumab (XGEVA®) is a fully human monoclonal antibody against RANKL, shown to be superior to zoledronic acid (ZA; Zometa®) for the prevention of SREs in patients with solid tumors. Denosumab also delayed the onset of moderate or severe pain compared with ZA. The pain severity and analgesic use associated with each type of SRE were assessed in patients with advanced breast cancer and bone metastases.

Methods: Eligible patients received denosumab 120 mg SC or ZA 4 mg (adjusted for renal function) IV every 4 weeks in a randomized, multinational, double-blind, double-dummy trial. Patient-reported pain was assessed with the Brief Pain Inventory (BPI; 0 no pain to 10 severe pain) at baseline (BL) and at each monthly visit. Opioid and non-opioid analgesic use was recorded and scored using the Analgesic Quantification Algorithm (AQA; 0 no analgesic use to 7 > 600mg oral morphine equivalent/day). Data from the two treatment arms were pooled for this analysis. Pain and analgesic use were evaluated from 6 months prior to and 6 months after the first on-study SRE for each patient. The comparator group included patients without an SRE and was centered at the median time from randomization to first SRE by SRE type, with corresponding 12 month assessments. The proportion of patients with moderate/severe pain (BPI worst pain score > 4) and proportion of patients shifting from no/low analgesic use (AQA ≤ 2) at baseline to strong opioid use (AQA ≥ 3) were reported by month and by SRE type, and are summarized by mean relative change (%) across the time period.

Results: In total, 687 patients with first on-study SRE occurrences (PF=450, RB=201, SCC=16, SB=20) were analyzed. A similar proportion of patients with and without a PF had moderate/severe pain, but a higher proportion of patients with a PF shifted from no/low analgesic use to strong opioid use (mean relative increase 80%). Starting 3 months prior to the event, more patients with RB than those without had moderate/severe pain (27% mean relative increase) and shifted from no/low analgesic use to strong opioid use (mean relative increase 269%). Similar pain and analgesic use patterns were noted for patients with SCC (mean relative increase in pain: 63%; in AQA shift: 913%). More patients with SB than those without had moderate/severe pain in the 6 months leading on to SB (mean relative increase 51%). The difference was attenuated after SB, but during this time a much higher proportion of patients with SB shifted from no/mild opioid use to strong opioid use (mean relative increase 220%).

Discussion: SREs are associated with increased pain severity and analgesic use in patients with advanced breast cancer and bone metastasis. Patterns of pain severity and analgesic use differed by SRE type. Effective treatments to prevent SREs can decrease pain and the need for treatment with opioid analgesics.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-13-01.

OT1-01-03: A Phase 3 Randomized, Double-Blind, Placebo-Controlled Multicenter Study Comparing Denosumab with Placebo as Adjuvant Treatment for Women with Early-Stage Breast Cancer Who Are at High Risk of Disease Recurrence (D-CARE)

Background

Bone is a common site of distant recurrence in women with early-stage breast cancer. Cancer cells are thought to stimulate osteoclast-mediated bone resorption, which releases growth factors and cytokines that promote tumor growth. RANK Ligand (RANKL) is the key mediator of osteoclast-induced bone destruction. In preclinical studies, RANKL inhibition reduced the incidence of bone and lung metastases, suppressed tumor progression, and prolonged survival of tumor-bearing mice. Effects were additive with hormonal, chemotherapy, or targeted therapies. Denosumab is a fully human monoclonal antibody against RANKL, approved in the U.S. for the prevention of skeletal-related events in patients with bone metastases from solid tumors. In patients with castrate-resistant prostate cancer, denosumab significantly improved bone metastasis-free survival (BMFS) compared to placebo. The D-CARE trial evaluates BMFS effects of denosumab in women with stage II or III breast cancer.

Methods: Women with node-positive or locally advanced (T3 or T4) disease, and known hormone and HER-2 receptor status are eligible. Standard-of-care adjuvant or neoadjuvant chemo-, endocrine, or HER-2 targeted therapy, alone or in combination must be planned with curative intent. Women with a prior history of breast cancer (other than ductal carcinoma in situ [DCIS] or lobular carcinoma in situ [LCIS]) or distant metastasis, oral bisphosphonate (BP) use within 1 year or any intravenous BP use are excluded. Patients are randomized 1:1 to receive denosumab 120 mg or placebo subcutaneously monthly for 6 mos, then every 3 mos, for a total of 5 yrs treatment. All patients receive vitamin D (≥ 400 IU) and calcium (≥ 500 mg) supplements. Primary endpoint of this event-driven trial is BMFS. Secondary endpoints include disease-free (DFS) and overall survival. The study is powered for both, BMFS and DFS. Safety, quality of life assessments and biomarkers are additional endpoints. The trial, sponsored by Amgen Inc. and registered with the ClinicalTrials.gov identifier NCT01077154 began enrolling patients in June 2010. PG and DF are supported in part by the Avon Foundation, NY.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT1-01-03.

Symptomatic treatment of ascites with a peritoneo-vesical automated fluid shunt system in a dog

A six-year-old Rottweiler with chronic ascites and moderate panhypoproteinaemia that had been treated with large volume paracentesis over several months duration was diagnosed with a large bi-atrial mass and hepatic fibrosis. For palliative treatment, a peritoneo-vesical automated fluid shunt system with an integrated chargeable battery and an integrated computer to control pump function and to transmit data transcutaneously was implanted by coeliotomy. The pump was left in place for 10 weeks, eliminating the need for further paracentesis during this time. At the end of this period, no ascites was discernible and serum protein concentrations had returned to their respective reference intervals. As a complication, decubitus with skin perforation had developed above the pump. Besides palliative treatment of chronic refractory ascites, this pump may have application in other conditions characterised by chronic cavity effusion or in peritoneal dialysis.

Oxytocin administration attenuates stress reactivity in borderline personality disorder: a pilot study

Oxytocin has known stress-reducing and attachment-enhancing effects. We thus hypothesized that oxytocin would attenuate emotional and hormonal responses to stress in borderline personality disorder (BPD). Fourteen BPD and 13 healthy control (HC) adults received 40 IU intranasal oxytocin or placebo in double-blind randomized order followed by the Trier Social Stress Test. Subjective dysphoria (Profile of Mood Changes) and plasma cortisol levels were measured. Childhood trauma history, attachment style, and self-esteem were also rated. A significant "Group × Drug × Time" interaction effect for dysphoria (p=.04) reflected a proportionately greater attenuation of stress-induced dysphoria in the BPD group after oxytocin administration. Additionally, a marginally significant "Group × Drug" interaction effect for cortisol (p=.10) reflected a tendency toward greater attenuation of the stress-induced cortisol surge in the BPD group after oxytocin administration. In the combined sample, the oxytocin-placebo difference in the emotional stress reactivity was significantly predicted by childhood trauma alone (p=.037) and combined with self-esteem (p=.030), whereas the oxytocin-placebo difference in cortisol stress reactivity was predicted only by insecure attachment (p=.013). Results suggest that oxytocin may have a beneficial impact on emotional regulation in BPD, which merits further investigation and could have important treatment implications.

Identifying patients with axial spondyloarthritis in primary care: how useful are items indicative of inflammatory back pain?

Background

The value of clinical items defining inflammatory back pain to identify patients with axial spondyloarthritis (SpA) in primary care is unclear.

Objective

To identify predictive clinical parameters for a diagnosis of axial SpA in patients with chronic back pain presenting in primary care.

Methods

Consecutive patients aged <45 years (n=950) with back pain for >2 months who presented to orthopaedic surgeons (n=143) were randomised based on four key questions for referral to rheumatologists (n=36) for diagnosis.

Results

The rheumatologists saw 322 representative patients (mean age 36 years, 50% female, median duration of back pain 30 months). 113 patients (35%) were diagnosed as axial SpA (62% HLA B27+), 47 (15%) as ankylosing spondylitis (AS) and 66 (21%) as axial non-radiographic SpA (nrSpA). Age at onset ≤35 years, improvement by exercise, improvement with non-steroidal anti-inflammatory drugs, waking up in the second half of the night and alternating buttock pain were identified as most relevant for diagnosing axial SpA by multiple regression analysis. Differences between AS and nrSpA were detected. No single item was predictive, but ≥3 items proved useful for good sensitivity and specificity by receiver operating characteristic modelling.

Conclusion

This study shows that a preselection in primary care of patients with back pain based on a combination of clinical items is useful to facilitate the diagnosis of axial SpA.

The neuropeptide calcitonin gene-related peptide affects allergic airway inflammation by modulating dendritic cell function

BACKGROUND

The neuropeptide calcitonin gene-related peptide (CGRP) is released in the lung by sensory nerves during allergic airway responses. Pulmonary dendritic cells (DC) orchestrating the allergic inflammation could be affected by CGRP.

OBJECTIVE

To determine the immunomodulatory effects of CGRP on DC function and its impact on the induction of allergic airway inflammation.

METHODS

CGRP receptor expression on lung DC was determined by RT-PCR and immunofluorescence staining. The functional consequences of CGRP receptor triggering were evaluated in vitro using bone marrow-derived DC. DC maturation and the induction of ovalbumin (OVA)-specific T cell responses were analysed by flow cytometry. The in vivo relevance of the observed DC modulation was assessed in a DC-transfer model of experimental asthma. Mice were sensitized by an intrapharyngeal transfer of OVA-pulsed DC and challenged with OVA aerosol. The impact of CGRP pretreatment of DC on airway inflammation was characterized by analysing differential cell counts and cytokines in bronchoalveolar lavage fluid (BALF), lung histology and cytokine responses in mediastinal lymph nodes.

RESULTS

RT-PCR, immunofluorescence and cAMP assay demonstrated the expression of functionally active CGRP receptors in lung DC. RT-PCR revealed a transcriptional CGRP receptor down-regulation during airway inflammation. CGRP specifically inhibited the maturation of in vitro generated DC. Maturation was restored by blocking with the specific antagonist CGRP(8-37) . Consequently, CGRP-pretreated DC reduced the activation and proliferation of antigen-specific T cells and induced increased the numbers of T regulatory cells. The transfer of CGRP-pretreated DC diminished allergic airway inflammation in vivo, shown by reduced eosinophil numbers and increased levels of IL-10 in BALF.

CONCLUSIONS AND CLINICAL RELEVANCE

CGRP inhibits DC maturation and allergen-specific T cell responses, which affects the outcome of the allergic airway inflammation in vivo. This suggests an additional mechanism by which nerve-derived mediators interfere with local immune responses. Thus, CGRP as an anti-inflammatory mediator could represent a new therapeutic tool in asthma therapy.

Bronchoconstriction in nonhuman primates: a species comparison

Bronchoconstriction is a characteristic symptom of various chronic obstructive respiratory diseases such as chronic obstructive pulmonary disease and asthma. Precision-cut lung slices (PCLS) are a suitable ex vivo model to study physiological mechanisms of bronchoconstriction in different species. In the present study, we established an ex vivo model of bronchoconstriction in nonhuman primates (NHPs). PCLS prepared from common marmosets, cynomolgus macaques, rhesus macaques, and anubis baboons were stimulated with increasing concentrations of representative bronchoconstrictors: methacholine, histamine, serotonin, leukotriene D₄ (LTD₄), U46619, and endothelin-1. Alterations in the airway caliber were measured and compared with previously published data from rodents, guinea pigs, and humans. Methacholine induced maximal airway constriction, varying between 74 and 88% in all NHP species, whereas serotonin was ineffective. Histamine induced maximal bronchoconstriction of 77 to 90% in rhesus macaques, cynomolgus macaques, and baboons and a lesser constriction of 53% in marmosets. LTD₄ was ineffective in marmosets and rhesus macaques but induced a maximum constriction of 44 to 49% in cynomolgus macaques and baboons. U46619 and endothelin-1 caused airway constriction in all NHP species, with maximum constrictions of 65 to 91% and 70 to 81%, respectively. In conclusion, PCLS from NHPs represent a valuable ex vivo model for studying bronchoconstriction. All NHPs respond to mediators relevant to human airway disorders such as methacholine, histamine, U46619, and endothelin-1 and are insensitive to the rodent mast cell product serotonin. Only PCLS from cynomolgus macaques and baboons, however, responded also to leukotrienes, suggesting that among all compared species, these two NHPs resemble the human airway mechanisms best.

The NKT cell ligand αgalactosylceramide suppresses allergic airway inflammation by induction of a Th1 response

One experimental approach for the treatment of allergic reactions is the stimulation of immunoregulatory NKT cells with the synthetic glycolipid αgalactosylceramide. For a first evaluation of the immunomodulatory potential of αGalCerMPEG a human in vitro allergy model was exploited. Acting as an adjuvant, the glycolipid induced an enhanced Th1-biased allergen-specific immune response of autologous lymphocytes. In a mouse model of allergic airway inflammation, αGalCerMPEG-activated NKT cells promoted a cytokine environment in the spleen, leading to priming of Th1 cells. The shift towards a Th1-dominated allergen-specific immune response thus might mediate the abrogation of allergic airway inflammation and thereby might provide a valid option for therapeutic intervention.

A Study on Oxidized Glassy Carbon sheets for Bipolar Supercapacitor Electrodes

Electrochemical Double Layer Capacitors (EDLC) for high energy and power density applications, based on glassy carbon (GO) electrodes, are being developed in our laboratory. In the context of this project, GC sheets were oxidized and investigated with Small Angle X-ray Scattering (SAXS), Electrochemical Impedance Spectroscopy (EIS) and Nitrogen Gas Adsorption (BET). During oxidation an active film with open pores is built on the surface of the GC. Upon oxidation, the internal volumetric surface area of the active film decreases, whereas the volumetric electrochemical double layer capacitance increases. We show that this effect is correlated with the opening, the growth and the coalescence of the pores.

[Innervation of the airways in asthma bronchiale and chronic obstructive pulmonary disease (COPD)]

Airway nerves have the capacity to control airway functions via neuronal reflexes and through neuromediators and neuropeptides. Neuronal mechanisms are known to play a key role in the initiation and modulation of airway hyperresponsiveness and inflammation. Therefore, the nerve fibres may contribute to airway narrowing in asthma and COPD. In addition to the traditional transmitters such as norepinephrine in postganglionic sympathetic nerve fibres and acetylcholine in parasympathetic nerve fibres, a large number of neuropeptides have been identified to have different pharmacological effects on the muscle tone of the vessels and bronchi, mucus secretion and immune cells. Meanwhile, a broad range of stimuli including capsaicin, bradykinin, hyperosmolar saline, tobacco smoke, allergens, ozone, inflammatory mediators and even cold, dry air have been shown to activate sensory nerve fibres to release neuropeptides such as the tachykinins substance P (SP) and neurokinin A (NKA) to mediate neurogenic inflammation. Different aspects of the neurogenic inflammation have been well studied in animal models of chronic airway inflammation and anticholinergic agents such as ipratropium bromide (Atrovent (®)) and tiotropium bromide (Spiriva (®)) have been proved to be important when used as bronchodilators for the treatment of obstructive airway diseases such as COPD. However, little is known about the role of neurogenic airway inflammation in human diseases. In this review, we address the current knowledge of the airway sensory nerves in human asthma and COPD.

Abstract P6-14-09: Acute-Phase Reactions Following Treatment with Zoledronic Acid or Denosumab: Results from a Randomized, Controlled Phase 3 Study in Patients with Breast Cancer and Bone Metastases

Background: Intravenous (IV) bisphosphonates (BP) are currently used to treat bone metastases and prevent skeletal-related events (SRE) in patients with advanced breast cancer. In a phase 3 study, denosumab, a fully human monoclonal antibody against RANKL, was shown to be superior to zoledronic acid (ZA) in delaying or preventing SREs in patients with breast cancer and bone metastases. This prespecified analysis compares ZA and denosumab for the incidence of acute-phase reactions (flu-like syndrome including pyrexia, chills, flushing, bone pain, arthralgias, and myalgias) during the first 3 days after initial treatment in that study.

Methods: Eligible patients were randomized in a double-blind, double-dummy fashion to receive IV ZA 4 mg (adjusted for creatinine clearance as specified by the Zometa label) or subcutaneous denosumab 120 mg every 4 weeks. Most patients (99%) were women; mean (SD) age was 57 (12) years, and baseline characteristics were balanced between groups. Safety analyses were conducted in patients who received ≥1 dose of denosumab (N=1020) or ZA (N=1013). Patient records were searched for adverse events (AEs) and serious AEs that occurred during the first 3 days after the first administration of study drug, using 37 prespecified MedDRA 12.0 preferred terms potentially indicating acute-phase reactions. Per study protocol, AEs were considered serious if they were fatal, life-threatening, required or prolonged in-patient hospitalization, resulted in a persistent or significant disability, or were considered to present a significant medical hazard.

Results: AEs associated with acute-phase reactions in the first 3 days after treatment occurred in fewer patients in the denosumab group (10.4%) than in the ZA group (27.3%; P&lt;0.0001), and no events were attributed to denosumab. The most common acute-phase reaction AEs included pyrexia (0.9% denosumab, 11.5% ZA), fatigue (2.4% denosumab, 4.0% ZA), bone pain (1.3% denosumab, 3.6% ZA), chills (0.3% denosumab, 3.6% ZA), and arthralgia (1.5% denosumab, 3.2% ZA). No patients (0%) in the denosumab group and 10 patients (1%) in the ZA group reported serious AEs associated with acute-phase reactions during the first 3 days. These events included pyrexia (n=7); bone pain (n=2); and asthenia, back pain, chest pain, chills, headache, and malaise (n=1 each). For 6 of the 10 patients, events of pyrexia, chest pain, chills, and bone pain were resolved within 4 days. Three patients with serious acute-phase reaction AEs discontinued ZA treatment after the first dose. Conclusion: Patients treated with denosumab experienced no serious AEs of acute-phase reaction and significantly fewer overall AEs of acute-phase reaction than patients receiving ZA.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-14-09.

Abstract P1-13-05: The Effect of Treatment with Denosumab or Zoledronic Acid on Health-Related Quality of Life in Patients with Metastatic Breast Cancer

Background: Patients with breast cancer and bone metastases often experience skeletal-related events (SREs) and pain, which may impact health-related quality of life (HRQoL). Denosumab is a fully human monoclonal antibody against RANKL shown to be superior in delaying/preventing SREs and more effective in delaying moderate or severe pain in patients with advanced breast cancer compared with zoledronic acid (ZA). Previously reported results from this study population showed that both denosumab and ZA patients showed improvement or maintenance in HRQoL relative to baseline (BL), and a greater proportion of denosumab-treated patients had a clinically meaningful improvement in HRQoL. We now describe the effect of denosumab and ZA treatment on HRQoL among patients with varying degrees of pain at BL.

Methods: Enrolled patients received subcutaneous (SC) denosumab 120 mg or intravenous (IV) ZA 4 mg every 4 weeks in a double-blind, double-dummy fashion. Pain was evaluated using the Brief Pain Inventory — Short Form (BPI). Patients were divided into 2 subgroups based on the level of pain reported at BL: no/mild pain or moderate/severe pain. Patients completed the Functional Assessment of Cancer Therapy-General (FACT-G) questionnaire at BL, day 8, and before each monthly visit to assess overall HRQoL. Higher scores (range 0 to 108) represent better HRQoL. Improvement, maintenance, and worsening of HRQoL were assessed through month 18, when 30% of patients had dropped out due to death, disease progression, or withdrawal of consent. A change of ≥5 points (increase or decrease) in the FACT-G total score was considered a meaningful improvement.

Results: Among patients who reported no/mild pain at baseline, more denosumab-treated patients had a ≥5-point increase in their FACT-G score from month 4 onwards. Over the 18 month period, an average of 4.1% more (range: −0.6% to 9.3%) denosumab-treated patients experienced meaningful improvement in HRQoL than ZA-treated patients. There were also fewer denosumab-treated patients experiencing ≥5-point decrease in HRQoL over 18 months (average of 2.4% fewer [range:-4.4% to 6.3% fewer]). Similar patterns were also noted for patients with moderate/severe pain at baseline. An average of 3.0% more (range:-1.7% to 7.9%) denosumab-treated patients had ≥5-point increase in FACT-G scores compared with ZA-treated patients over 18 months. A lower proportion of denosumab-treated patients (3.5% fewer [range: −1.1% to 11.5% fewer]) than ZA-treated patients had a decrease ≥5-points in their FACT-G score over 18 months.

Conclusion: In patients with breast cancer and bone metastases, a greater proportion treated with denosumab than ZA had a meaningful improvement in HRQoL regardless of their pain level at BL.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-13-05.

Abstract P1-13-01: Comparing the Effects of Denosumab and Zoledronic Acid on Pain Interference with Daily Functioning in a Randomized Phase 3 Trial of Patients with Breast Cancer and Bone Metastases

In a recently completed trial of breast cancer patients with bone metastases, denosumab, a fully human monoclonal anti-RANKL antibody, was superior to zoledronic acid (ZA) in delaying/preventing skeletal-related events. Between-treatment differences in patient-reported pain interference with daily functioning were assessed.

Eligible breast cancer patients received monthly subcutaneous denosumab 120 mg or intravenous ZA 4 mg (double-bind, double-dummy design). Patients completed the Brief Pain Inventory (BPI) to assess pain severity and interference with daily functioning (range 0 [does not interfere]-10 [interferes completely]) at baseline (BL), day 8, and before each monthly visit through end of study. The BPI interference scale generated a total interference score as well as an activity subscale (interference with walking, general activity, and work) and an affective subscale (interference with relations with others, enjoyment of life, and mood). Analyses were conducted on all randomized patients with ≥1 PRO assessment and were performed through week 73, when 30% of patients had dropped out due to death, disease progression, or consent withdrawal. Subgroups included patients with no/mild and moderate/severe worst pain at BL. Analyses included time to improvement (≥2-point decrease) or worsening (≥2-point increase) in pain interference, mean change from baseline, and proportion of patients with improving or worsening pain interference scores. Time to improvement in pain interference with activity (PIWA) tended to occur more quickly with denosumab compared with ZA (N=1124; median: 70 days denosumab v 86 days ZA; P=0.09), and time to worsening PIWA tended to be longer with denosumab compared with ZA (N=1676; median: 394 days denosumab v 310 days ZA; P=0.13). In patients with no/mild pain at BL, denosumab also demonstrated a trend for shorter time to improvement in PIWA (N=388; 93 days denosumab v 120 days ZA; P=0.06) and longer time to worsening PIWA (N=755; 369 days denosumab v 232 days ZA; P=0.12). Overall, a greater proportion of patients on denosumab had improvement in PIWA on study than ZA (Figure). Findings were similar with the total interference score and affective subscale.

Figure Proportion of Patients With Improvement in Pain Interference With Activity (≥2-point decrease from BL)*

Daily functioning (total interference and interference with activity and affect) tended to be less disrupted by pain in patients on denosumab compared with ZA. Decreased pain interference showed a trend to occur more quickly with denosumab. Overall, a greater proportion of denosumab patients reported decreased pain interference than ZA patients.

Effects of an alpha-4 integrin inhibitor on restenosis in a new porcine model combining endothelial denudation and stent placement

Restenosis remains the main complication of balloon angioplasty and/or stent implantation. Preclinical testing of new pharmacologic agents preventing restenosis largely rely on porcine models, where restenosis is assessed after endothelial abrasion of the arterial wall or stent implantation. We combined endothelial cell denudation and implantation of stents to develop a new clinically relevant porcine model of restenosis, and used this model to determine the effects of an α4 integrin inhibitor, ELN 457946, on restenosis. Balloon-angioplasty endothelial cell denudation and subsequent implantation of bare metal stents in the left anterior descending coronary, iliac, and left common carotid arteries was performed in domestic pigs, treated with vehicle or ELN 457946, once weekly via subcutaneous injections, for four weeks. After 1 month, histopathology and morphometric analyses of the arteries showed complete healing and robust, consistent restenotic response in stented arteries. Treatment with ELN 457946 resulted in a reduction in the neointimal response, with decreases in area percent stenosis between 12% in coronary arteries and 30% in peripheral vessels. This is the first description of a successful pig model combining endothelial cell denudation and bare metal stent implantation. This new double injury model may prove particularly useful to assess pharmacological effects of drug candidates on restenosis, in coronary and/or peripheral arteries. Furthermore, the ELN 457946 α4 integrin inhibitor, administered subcutaneously, reduced inflammation and restenosis in stented coronary and peripheral arteries in pigs, therefore representing a promising systemic therapeutic approach in reducing restenosis in patients undergoing angioplasty and/or stent implantation.

Pituitary adenylate cyclase-activating peptide receptor 1 mediates anti-inflammatory effects in allergic airway inflammation in mice

BACKGROUND

Bronchial asthma is characterized by airway inflammation and reversible obstruction. Since the gold standard of therapy, a combination of anti-inflammatory corticosteroids and bronchodilatory β(2) agonists, has recently been discussed to be related to an increased mortality, there is a need for novel therapeutic pathways.

OBJECTIVE

A new experimental concept that encompasses the vasoactive intestinal peptide/pituitary adenylate cyclase activating peptide (PACAP) family of receptors by demonstrating the anti-inflammatory effects of the PACAP receptor 1 (PAC1R) in a murine model of allergic asthma is described.

METHODS

PAC1R expression was investigated in lung tissue and isolated dendritic cells (DCs) via real-time PCR. Ovalbumin (OVA)-induced asthma models were used in PAC1R-deficient mice and BALB/c mice treated with PAC1R agonist maxadilan (MAX). Bronchoalveolar lavages have been performed and investigated at the cellular and cytokine levels. Fluorescence staining of a frozen lung section has been performed to detect eosinophil granulocytes in lung tissue. Plasma IgE levels have been quantified via the ELISA technique. Lung function was determined using head-out body plethysmography or whole-body plethysmography.

RESULTS

Increased PAC1R mRNA expression in lung tissue was present under inflammatory conditions. PAC1R expression was detected on DCs. In OVA-induced asthma models, which were applied to PAC1R-deficient mice (PAC1R(-/-)) and to BALB/c mice treated with the specific PAC1R agonist MAX, PAC1R deficiency resulted in inflammatory effects, while agonistic stimulation resulted in anti-inflammatory effects. No effects on lung function were detected both in the gene-depletion and in the pharmacologic studies. In summary, here, we demonstrate that anti-inflammatory effects can be achieved via PAC1R.

CONCLUSION

PAC1R agonists may represent a promising target for an anti-inflammatory therapy in airway diseases such as bronchial asthma.

A short receptor downregulates JAK/STAT signalling to control the Drosophila cellular immune response

Regulation of JAK/STAT signalling by a short, nonsignalling receptor in Drosophila modulates response to specific immune challenges such as parasitoid infestations.

The posterior signalling centre (PSC), a small group of specialised cells, controls hemocyte (blood cell) homeostasis in the Drosophila larval hematopoietic organ, the lymph gland. This role of the PSC is very reminiscent of the “niche,” the micro-environment of hematopoietic stem cells in vertebrates. We have recently shown that the PSC acts in a non–cell-autonomous manner to maintain janus tyrosine kinase/signal transducers and activators of transcription (JAK/STAT) signalling in hematopoietic progenitors (prohemocytes), thereby preserving the multipotent character necessary for their differentiation into lamellocytes, a cryptic and dedicated immune cell type required to fight specific immune threats such as wasp parasitism. In this report, on the basis of a knock out generated by homologous recombination, we show that a short type I cytokine-related receptor CG14225/Latran is required for switching off JAK/STAT signalling in prohemocytes. This is a prerequisite to massive differentiation of lamellocytes upon wasp parasitisation. In vivo and cell culture assays indicate that Latran forms heteromers with Domeless, the Drosophila type I cytokine signalling receptor related to mammalian GP130, and antagonises Domeless activity in a dose-dependent manner. Our analysis further shows that a primary immune response to wasp parasitism is a strong decrease in cytokine mRNA levels in the lymph gland, followed by an increase in the latran/domeless ratio. We propose that this sequence of events culminates in the complete inhibition of residual JAK/STAT signalling by Latran. JAK/STAT activity has been associated with several human diseases including leukaemia while knock-out studies in mice point to a central role of this pathway in hematopoiesis and regulation of immune functions. The specific function of Drosophila Latran is, to our knowledge, the first in vivo example of a role for a nonsignalling receptor in controlling a dedicated immune response, and thus raises the question of whether short, nonsignalling receptors also control specific aspects of vertebrate cellular immunity.

A specific microenvironment termed the “niche” supports long term maintenance of hematopoietic stem cells in vertebrates. A small group of specialised cells called the posterior signalling center (PSC) controls hemocyte (blood cell) homeostasis in the Drosophila larval hematopoietic tissue and thus fulfills a similar function to the vertebrate niche. The PSC acts at a distance to maintain JAK/STAT signalling in hematopoietic progenitors (prohemocytes), thereby ensuring their multipotent character. We report here that a short cytokine receptor encoded by CG14225/latran is required to extinguish JAK/STAT signalling in prohemocytes and thereby ensures their mass differentiation into lamellocytes, an immune cell type required to fight specific threats such as wasp parasitism. Domeless, a related receptor in Drosophila, was previously the only known cytokine receptor that signals through the JAK/STAT pathway. We show that Latran lacks the intracellular domains required for signal transduction and acts instead by antagonizing the function of Domeless in a dose-dependent manner. The role of Drosophila Latran in the repression of JAK/STAT signalling under specific immune conditions raises the question of whether short, nonsignalling receptors that antagonize full-length receptors could also control specific aspects of vertebrate immunity.