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1.
Arthritis Res Ther ; 17: 343, 2015 Nov 27.
Article in English | MEDLINE | ID: mdl-26614481

ABSTRACT

INTRODUCTION: The effect of certolizumab pegol (CZP) on patient-reported outcomes (PROs) was investigated in 1063 patients with rheumatoid arthritis (RA) from the REALISTIC trial (double-blind, placebo-controlled to week 12, open-label to week 28; randomized 4:1 [CZP:placebo]). Correlations between PROs and RA signs and symptoms, and the relative efficacy of these measures, were examined. METHODS: Adults with RA and an inadequate response to at least one disease-modifying antirheumatic drug were enrolled. PROs assessed included physical function (using the Health Assessment Questionnaire-Disability Index), pain, fatigue, sleep disturbance, Patient Global Assessment of Disease Activity (PtGA), Routine Assessment of Patient Index Data 3 (RAPID3), and Rheumatoid Arthritis Disease Activity Index (RADAI). RESULTS: Early significant and clinically meaningful improvements in all PROs were observed to week 12 with CZP vs. placebo and were maintained to the end of the trial (week 28). At week 12, up to one-third more CZP patients showed improvements compared with placebo that were greater than or equal to the minimal clinically important difference (MCID) in fatigue, sleep problems, pain, PtGA, RADAI, and RAPID3. The changes in PROs were correlated with clinical measures of disease activity, including the Disease Activity Score in 28 joints using C-reactive protein as well as tender and swollen joint counts. CONCLUSIONS: Rapid improvements in PROs were seen in patients with RA treated with CZP. The magnitude of improvement exceeded the MCID in multiple domains and demonstrated that CZP improves aspects of health-related quality of life that are meaningful to patients and superior to placebo. PROs provide information complementary to clinical outcomes in assessment of treatment benefits. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00717236 . Registered on 15 July 2008.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Certolizumab Pegol/therapeutic use , Double-Blind Method , Female , Humans , Male , Middle Aged , Self Report , Surveys and Questionnaires , Treatment Outcome
2.
Rheumatology (Oxford) ; 54(10): 1842-51, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26001635

ABSTRACT

OBJECTIVES: Several patient-reported outcome (PRO) instruments have been validated in AS. This study aims to evaluate several measurement properties of such PROs in a broad axial SpA (axSpA) population, including both AS and non-radiographic axSpA (nr-axSpA) subpopulations. METHODS: PROs assessed were total and nocturnal back pain, patient global assessment of disease activity, BASDAI, BASFI and the 36-item Short Form Health Survey. A literature review and both clinician and patient qualitative interviews provided information on instrument content validity. Reliability (test-retest and internal consistency), construct validity (PROs, clinical-outcome correlations and known-groups validity) and PRO responsiveness were assessed. Data from the RAPID-axSpA trial (NCT01087762) investigating certolizumab pegol efficacy in axSpA, including relevant subpopulations, were utilized. RESULTS: Concepts identified for the broad axSpA population by both clinician and patient interviews were consistent with those identified through literature review of AS. All PROs demonstrated reliability in the RAPID-axSpA population (n = 325), with test-retest intraclass correlation coefficients and internal consistency Cronbach's α >0.8. Validity was supported by agreement between PROs and clinician-rated measures; except for the 36-item Short Form Health Survey Mental Components Summary, correlations between PROs and physician global assessment of disease activity ranged from 0.28 to 0.42 for week 0 and from 0.53 to 0.65 for week 24. PRO measures showed good sensitivity to change (effect size >0.8) at weeks 12 and 24 for responders. No variations in measurement properties were noted between the subpopulations. CONCLUSION: This study indicates that both content validity and measurement properties of PRO instruments utilized in AS are preserved in the broad axSpA population.


Subject(s)
Axis, Cervical Vertebra , Outcome Assessment, Health Care , Patient Outcome Assessment , Psychometrics , Spondylarthritis/psychology , Spondylitis, Ankylosing/psychology , Adult , Communication , Female , Health Surveys , Humans , Male , Middle Aged , Physician-Patient Relations , Reproducibility of Results , Self Report , Spondylarthritis/therapy , Spondylitis, Ankylosing/therapy
3.
Clin Gastroenterol Hepatol ; 9(8): 670-678.e3, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21642014

ABSTRACT

BACKGROUND & AIMS: Certolizumab pegol (CZP) is a pegylated-conjugated Fab' against tumor necrosis factor (TNF). Additional data are needed regarding the efficacy of induction therapy with CZP in active Crohn's disease (CD). METHODS: A placebo-controlled trial evaluated the efficacy of CZP therapy in 439 adults with moderate to severe CD naive to anti-TNF therapy. Patients were randomized to receive CZP (400 mg subcutaneously) or placebo at weeks 0, 2, and 4. The primary end point was clinical remission at week 6. RESULTS: Clinical remission rates at week 6 in the CZP and placebo groups were 32% and 25% (P = .174), respectively. Remission rates at weeks 2 and 4 in the CZP and placebo groups were 23% and 16% (P = .033) and 27% and 19% (P = .063), respectively. Clinical response rates at weeks 2, 4, and 6 in the CZP and placebo groups were 33% and 20% (P = .001), 35% and 26% (P = .024), and 41% and 34% (P = .179), respectively. There were significantly greater rates of clinical remission at week 6 for CZP in patients with increased concentrations of C-reactive protein (≥5 mg/L) at entry. Serious adverse events developed in 5% and 4% of patients in the CZP and placebo groups, respectively. CONCLUSIONS: The primary end point did not reach statistical significance. Significant differences between CZP and placebo were observed in patients who had increased concentrations of C-reactive protein when the study began. Future clinical trials should emphasize the treatment of patients who have objective evidence of inflammation in addition to symptoms of active disease.


Subject(s)
Crohn Disease/drug therapy , Immunoglobulin Fab Fragments/administration & dosage , Immunologic Factors/administration & dosage , Polyethylene Glycols/administration & dosage , Adolescent , Adult , Aged , Antibodies, Monoclonal, Humanized , C-Reactive Protein/analysis , Certolizumab Pegol , Female , Humans , Male , Middle Aged , Placebos/administration & dosage , Treatment Outcome , Young Adult
4.
J Rheumatol ; 38(6): 990-6, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21362764

ABSTRACT

OBJECTIVE: To assess the kinetics of response to certolizumab pegol (CZP), and association between rapid response and longterm outcomes, in patients with active rheumatoid arthritis (RA). METHODS: This was a post-hoc analysis of the randomized, double-blind RAPID 1 study in patients who received methotrexate (MTX) and either CZP 200 mg subcutaneously or placebo every 2 weeks for 52 weeks. Clinical and radiographic outcomes at Week 52 were evaluated based on the Disease Activity Score 28 (DAS28) ≥ 1.2 and American College of Rheumatology 20% (ACR20) responses at Week 6 and Week 12. RESULTS: Clinical responses [European League Against Rheumatism (EULAR), DAS28 ≥ 1.2, and ACR20 responses] were rapid in CZP-treated patients. Week 12 DAS28 ≥ 1.2 responders had better clinical and radiographic outcomes at Week 52 compared with nonresponders. Among Week 12 responders, incremental benefit of earlier response was observed: Week 6 DAS28 ≥ 1.2 responders and ACR20 responders had significantly higher ACR response rates and were more likely to achieve remission at Week 52 than Week 12 responders. Patients with a clinical response at Week 6 had faster, more meaningful sustained improvements in patient-derived outcomes than those responding by Week 12 only. CONCLUSION: Rapid attainment of clinical response in patients with RA is associated with improved longterm outcomes. Analysis of the kinetics of response to CZP during the first 12 weeks of therapy potentially permits informed prediction of clinical success or need to alter treatment. In patients not achieving a clinical response at Week 12 treatment adjustment should be considered. Trial registration NCT00152386.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/diagnosis , Arthritis, Rheumatoid/drug therapy , Immunoglobulin Fab Fragments/therapeutic use , Polyethylene Glycols/therapeutic use , Adult , Antibodies, Monoclonal, Humanized , Arthritis, Rheumatoid/diagnostic imaging , Certolizumab Pegol , Double-Blind Method , Humans , Longitudinal Studies , Male , Methotrexate/therapeutic use , Middle Aged , Prognosis , Radiography , Treatment Outcome
5.
Ann Rheum Dis ; 70(6): 996-1002, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21415050

ABSTRACT

OBJECTIVE: To assess the impact of certolizumab pegol (CZP) on patient-reported outcomes (PROs) in rheumatoid arthritis (RA), and to interpret these results using number needed to treat (NNT), and associations between PRO responses and longer term outcomes. METHODS: A total of 619 patients with active RA were randomised to CZP 200 or 400 mg, or placebo plus methotrexate (MTX). PROs assessed included pain, patient's global assessment of disease activity (PtGA), physical function, fatigue and health-related quality of life. Treatment impact on PROs, NNT to achieve simultaneous improvements in multiple PROs and correlations between PROs were calculated. Times to onset of improvements greater than or equal to minimum clinically important differences (MCIDs) in pain as a determinant of clinical outcomes at week 24 were compared between week 6 and 12 responders, and in patients with improvements in pain ≥ MCID at week 12 (week 12 responders/non-responders). RESULTS: CZP 200 and 400 mg plus MTX were associated with rapid, clinically meaningful improvements in all PROs. The NNT for subjects to report changes ≥MCID in up to five PROs was two to three, and five for all six PROs (pain, PtGA, physical function, fatigue and short-form 36-item Physical and Mental Component Summary Scores). More patients with improvements ≥MCID in pain at week 6 than those at week 12 had lower disease activity at week 24. Week 12 pain responders had better clinical outcomes at week 24 than non-responders. CONCLUSIONS: The data demonstrate that CZP provides broad relief from the burden of RA. Trial registration number NCT00160602.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Immunoglobulin Fab Fragments/therapeutic use , Methotrexate/therapeutic use , Polyethylene Glycols/therapeutic use , Adult , Antibodies, Monoclonal, Humanized , Antirheumatic Agents/administration & dosage , Arthritis, Rheumatoid/complications , Certolizumab Pegol , Dose-Response Relationship, Drug , Drug Administration Schedule , Drug Therapy, Combination , Epidemiologic Methods , Fatigue/etiology , Female , Humans , Immunoglobulin Fab Fragments/administration & dosage , Male , Middle Aged , Pain/etiology , Pain Measurement/methods , Polyethylene Glycols/administration & dosage , Quality of Life , Treatment Outcome
6.
Health Qual Life Outcomes ; 9: 2, 2011 Jan 13.
Article in English | MEDLINE | ID: mdl-21232106

ABSTRACT

BACKGROUND: Subcutaneous self-injection of medication has benefits for the patient and healthcare system, but there are barriers such as dexterity problems and injection anxiety that can prevent self-injection being used effectively. An accurate method of evaluating patients' experiences with self-injection would enable assessment of their success in giving self-injections and the likelihood of them adhering to a self-injection regimen. The aim of this study was to develop a questionnaire to measure overall patient experience with subcutaneous self-injection (the Self-Injection Assessment Questionnaire [SIAQ]), and to investigate its psychometric properties. METHODS: The construct validity and reliability of the SIAQ were tested in patients with rheumatoid arthritis who volunteered to inject certolizumab pegol using a standard syringe during an open-label multinational extension trial of the long-term safety and efficacy of this drug. The SIAQ PRE module was self-completed before the first self-injection, and the POST module was self-completed following each of three fortnightly self-injections. RESULTS: Ninety-seven patients completed the SIAQ. All items correlated well with their respective domains in confirmatory factor analysis. As predicted, compared with other participants, patients with very low scores (less than 3 out of 10) in PRE causal domains (Feelings about injections and Self-confidence) were significantly less satisfied with their first self-injection, as were patients with a very low score in any POST causal domain (Self-confidence, Feelings about injections, Injection-site reactions and Ease of use), demonstrating known-groups validity. Causal domain scores generally correlated most strongly with the Satisfaction with self-injection domain, supporting convergent validity. The SIAQ demonstrated internal consistency and reproducibility; Cronbach's α and the test-retest coefficient were > 0.70 for all domains. Sensitivity and responsiveness were also shown, where measurable. Each language version showed structural validity. CONCLUSION: The SIAQ was demonstrated to be a valid, reliable tool in patients with rheumatoid arthritis.


Subject(s)
Arthritis, Rheumatoid/drug therapy , Psychometrics/standards , Self Administration/psychology , Surveys and Questionnaires , Adult , Aged , Antirheumatic Agents/administration & dosage , Arthritis, Rheumatoid/psychology , Factor Analysis, Statistical , Female , Humans , Injections, Subcutaneous , Male , Middle Aged , Quality of Life , Reproducibility of Results
7.
Rheumatology (Oxford) ; 49(10): 1900-10, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20547658

ABSTRACT

OBJECTIVES: To evaluate the association between improvements in physical function, fatigue and pain and improvements in productivity at work and at home in patients treated with certolizumab pegol (CZP) in combination with MTX. METHODS: Physical function, fatigue and pain were assessed in two CZP clinical trials (Rheumatoid Arthritis PreventIon of structural Damage 1 and 2) using the HAQ-Disability Index (HAQ-DI), Fatigue Assessment Scale (FAS) and Patient Assessment of Pain, with minimal clinically important differences (MCIDs) defined as ≥ 0.22, ≥ 1 and ≥ 10 points, respectively. Work and home productivity were evaluated using the RA-specific Work Productivity Survey (WPS-RA). The odds of achieving an HAQ-DI, FAS or pain 'response' at Week 12, defined as improvements ≥ MCID, were compared between CZP and control groups. Improvements in productivity at Week 12 were compared between CZP-treated HAQ-DI, FAS or pain responders and non-responders. RESULTS: The odds of achieving improvements ≥ MCID were five times higher for pain, and two to three times higher for physical function and fatigue, in patients receiving CZP vs control. Per month, responders reported significantly greater improvements in productivity at work and reduced interference of RA with their work productivity than non-responders. Responders also reported significantly greater improvements in productivity at home and participation in family, social and leisure activities. CONCLUSIONS: This study demonstrated a clear association between patient-reported improvements in physical function, fatigue and pain, and improvements in productivity both at work and home.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Efficiency/drug effects , Immunoglobulin Fab Fragments/therapeutic use , Polyethylene Glycols/therapeutic use , Activities of Daily Living , Adult , Antibodies, Monoclonal, Humanized , Arthritis, Rheumatoid/physiopathology , Certolizumab Pegol , Fatigue/drug therapy , Fatigue/physiopathology , Female , Humans , Leisure Activities , Male , Middle Aged , Pain/drug therapy , Pain/physiopathology , Quality of Life , Randomized Controlled Trials as Topic , Severity of Illness Index , Statistics as Topic , Treatment Outcome
8.
Arthritis Res Ther ; 11(6): R170, 2009.
Article in English | MEDLINE | ID: mdl-19909548

ABSTRACT

INTRODUCTION: The objective of this study was to assess the impact of certolizumab pegol (CZP) treatment on health-related quality of life (HRQoL), fatigue and other patient-reported outcomes (PROs) in patients with rheumatoid arthritis (RA). METHODS: Patients with active RA (N = 982) were randomized 2:2:1 to subcutaneous CZP (400 mg at weeks 0, 2 and 4; followed by CZP 200 mg or 400 mg) plus methotrexate (MTX) every other week, or placebo (PBO) plus MTX. PRO assessments included HRQoL, fatigue, physical function, arthritis pain and disease activity. Adjusted mean changes from baseline in all PROs were obtained using analysis of covariance (ANCOVA) applying last observation carried forward (LOCF) imputation. The proportion of patients achieving clinically meaningful improvements in each PRO was obtained using logistic regression and by applying non-responder imputation to missing values after rescue medication or withdrawal. The correlations between PRO responses and clinical responses were also assessed by tetrachoric correlation using non-responder imputation. RESULTS: Patients treated with CZP plus MTX reported significant (P < 0.001), clinically meaningful improvements in HRQoL at the first assessment (week 12); reductions in fatigue, disease activity and pain and improvements in physical function were reported at week 1. In particular, CZP-treated patients reported improvements in mental health. Mean changes from baseline in the SF-36 Mental Component Summary (MCS) at week 52 for CZP 200 mg and 400 mg plus MTX, and PBO plus MTX were 6.4, 6.4 and 2.1, respectively (P < 0.001). In addition, mental health and vitality scores in CZP-treated patients approached age- and gender-adjusted US population norms. Improvements in all PROs were sustained. Similar benefits were reported with both CZP doses. Changes in SF-36 MCS scores had the lowest correlation with disease activity scores (DAS28) and American College of Rheumatology 20% improvement (ACR20) response rates, while improvements in pain showed the highest correlation. CONCLUSIONS: Treatment with CZP plus MTX resulted in rapid and sustained improvements in all PROs, indicating that the benefits of CZP extend beyond clinical efficacy endpoints into areas that are more relevant and meaningful for patients on a daily basis. TRIAL REGISTRATION: ClinicalTrials.gov NCT00152386.


Subject(s)
Antirheumatic Agents/administration & dosage , Arthritis, Rheumatoid/drug therapy , Fatigue/drug therapy , Immunoglobulin Fab Fragments/administration & dosage , Methotrexate/administration & dosage , Polyethylene Glycols/administration & dosage , Quality of Life , Activities of Daily Living , Antibodies, Monoclonal, Humanized , Certolizumab Pegol , Double-Blind Method , Drug Therapy, Combination , Fatigue/etiology , Female , Humans , Male , Middle Aged , Pain/drug therapy , Pain/etiology , Pain Measurement , Recovery of Function/drug effects , Severity of Illness Index
9.
Am J Gastroenterol ; 104(8): 1976-83, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19471252

ABSTRACT

OBJECTIVES: Moderate-to-severe Crohn's disease (CD) is associated with important impairment in health-related quality of life (HRQOL). The aim of this study was to assess the effects of certolizumab pegol (CZP) maintenance therapy on HRQOL. METHODS: During an open-label induction phase, study participants with moderate-to-severe CD were treated with 400 mg CZP every other week. Responders were randomized to monthly maintenance therapy with CZP or placebo. Clinically meaningful improvement in HRQOL was evaluated with three patient-reported outcome (PRO) instruments. Quality-adjusted life-years (QALYs) were calculated from utility scores derived from the EuroQoL-5 dimensions (EQ-5D). Normal life rating was measured by combining clinical disease activity, HRQOL, and measures of professional work productivity and daily activity. RESULTS: A total of 425 responders to induction therapy were randomized to CZP maintenance (n=215) or placebo (n=210). Participants assigned to CZP maintenance reported clinically meaningful improvements in HRQOL relative to baseline and to placebo-treated participants. More participants receiving treatment with CZP reported clinically meaningful improvement in Inflammatory Bowel Disease Questionnaire (IBDQ) score (60 vs. 43%, P<0.001) and in Short-Form 36-Item Health Survey (SF-36) physical (51 vs. 34%, P<0.001) and mental component summary responses (44 vs. 32%, P=0.016) than did those receiving placebo. The proportion of participants who achieved clinically meaningful improvement in the EQ-5D plus health status visual analogue scale (VAS) was significantly greater in those assigned to CZP maintenance than in those assigned placebo (57 vs. 38%, P<0.001). There was also a significantly greater gain in QALYs for the CZP group as compared with the placebo group (mean+/-s.d. 0.25+/-0.10 and 0.21+/-0.11; P=0.001). Significantly more participants receiving CZP maintenance reported living a normal life (21.4%) than did those receiving placebo (12.9%, P=0.019). CONCLUSIONS: Maintenance therapy with CZP resulted in statistically significant and clinically meaningful improvements in HRQOL, as assessed by multiple PRO instruments. CZP improved and maintained the quality and quantity of the remission and response, as measured by QALYs. Furthermore, a significant proportion of study participants who received CZP returned to a normal life compared with those who received placebo.


Subject(s)
Crohn Disease/drug therapy , Immunoglobulin Fab Fragments/therapeutic use , Polyethylene Glycols/therapeutic use , Quality of Life , Adult , Antibodies, Monoclonal, Humanized , Certolizumab Pegol , Double-Blind Method , Female , Humans , Male
10.
Arch Environ Contam Toxicol ; 56(2): 209-20, 2009 Feb.
Article in English | MEDLINE | ID: mdl-18458993

ABSTRACT

Impacts of the Erika oil spill on the common starfish Asterias rubens were investigated in the field and using laboratory experiments based on contamination via food at different stages of the starfish reproductive cycle. Two months after the shipwreck, levels of hydrocarbons characteristic of Erika fuel were significantly higher in pyloric ceca and body wall of A. rubens from a contaminated site, compared with control animals from an unpolluted reference area. Concomitant immunological responses and detoxification enzyme activity (CYP1A) were enhanced in the impacted starfish, suggesting rapid biotransformation processes. This was confirmed by laboratory experiments which showed a fast PAH uptake during the 10 first days of contamination and the start of biotransformation processes from the third day. Our study confirms benzo(a)pyrene hydroxylase activity (BPH) in A. rubens and demonstrates the influence of CYP1A in the conversion of insoluble PAHs into soluble derivatives in this species for the first time. The rapidity of decontamination could explain why starfish growth, level of motile activity, reproductive investment, energy storage, and larval development were not significantly affected by these contaminants.


Subject(s)
Asterias/drug effects , Petroleum/toxicity , Reproduction/drug effects , Water Pollutants, Chemical/toxicity , Animals , Asterias/enzymology , Asterias/growth & development , Biotransformation , Cytochrome P-450 CYP1A1/metabolism , Environmental Monitoring , France , Water Pollutants, Chemical/pharmacokinetics
11.
Dev Comp Immunol ; 31(8): 790-804, 2007.
Article in English | MEDLINE | ID: mdl-17240448

ABSTRACT

Despite the ecological and evolutionary importance of echinoderms, very little is known about the immune mechanisms in this group especially regarding humoral immunity. In this paper, we screened for proteins putatively involved in immunity in the common European seastar Asterias rubens using a mass spectrometry-based proteomic approach. Two proteins showed striking sequence similarities with peptidoglycan recognition proteins (PGRPs). The two seastar proteins were identified as a single protein, termed PGRP-S1a, occurring in two forms in the coelomic plasma, one of 20kDa and another of 22kDa. We also cloned and sequenced a second member of the PGRP family, termed PGRP-S2a. It has a calculated molecular mass of 21.3kDa and is expressed in circulating phagocytes. Both the S1a-cDNA from coelomic epithelium RNA and the S2a-cDNA from phagocytes code for the amino acid residues necessary for peptidoglycan degradation. PGRP-S1a did not affect the phagocytic activity of seastar immune cells towards Micrococcus luteus but inhibited their production of reactive oxygen species (ROS). A recombinant, His-tagged, PGRP-S2a degrades peptidoglycan and increases the phagocytosis of M. luteus cells by seastar phagocytes.


Subject(s)
Amidohydrolases/genetics , Asterias/enzymology , Asterias/immunology , Carrier Proteins/genetics , Carrier Proteins/immunology , Amidohydrolases/chemistry , Amidohydrolases/metabolism , Amino Acid Sequence , Animals , Asterias/genetics , Base Sequence , Carrier Proteins/chemistry , Cloning, Molecular , Immunity, Innate , Micrococcus luteus , Molecular Sequence Data , Peptidoglycan/metabolism , Phagocytosis , Protein Binding , Reactive Oxygen Species/metabolism , Sequence Homology, Amino Acid
12.
Environ Toxicol Chem ; 22(9): 2136-44, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12959542

ABSTRACT

The accumulation of Cd, Pb, Zn, and Cu in the starfish Asterias rubens was studied in a Norwegian fjord characterized by a gradient of metal pollution in the sediments, ranging from very high metal concentrations at its head to much lower levels at its opening. The concentrations of metals in starfish from natural populations along the gradient (long-term accumulation) and in starfish that were transferred up the gradient (short-term accumulation) were compared. At long-term, Cd and Pb accumulations by starfish living at normal salinity (30/1000) were related to the level of contamination of the environment while Cu and, to a lesser extent, Zn accumulations appeared strictly controlled. At short-term, Pb was accumulated steadily, Cd and Zn were accumulated transiently in the pyloric caeca (fast compartment), and Cu was not accumulated at all. Depuration experiments (transfer down the gradient) showed that Cd and Pb were efficiently eliminated from the pyloric caeca but not from the body wall (slow compartment). It is concluded that Pb is chronically accumulated, without apparent control, Cd is subjected to a regulating mechanism in the pyloric caeca which is overwhelmed over the long-term; Zn is tightly controlled in the pyloric caeca and Cu in both pyloric caeca and body wall. A distinct color variety of starfish is restricted to the low salinity (22-26/1000) superficial water layer. This variety showed a different pattern of metal accumulation over the long-term. This pattern is attributed to the particular hydrological conditions prevailing in this upper layer.


Subject(s)
Environmental Exposure , Geologic Sediments/chemistry , Metals, Heavy/pharmacokinetics , Starfish , Water Pollutants/pharmacokinetics , Animals , Seawater , Sodium Chloride/analysis , Tissue Distribution , Water Movements
13.
Environ Toxicol Chem ; 22(9): 2145-51, 2003 Sep.
Article in English | MEDLINE | ID: mdl-12959543

ABSTRACT

To study the effects of metals on starfish in field conditions, immune responses were measured in starfish from natural populations along a metal pollution gradient (long-term contamination) and in starfish that were transferred up the gradient (short-term contamination). Coelomic amoebocyte concentration (CAC) and production of reactive oxygen species (ROS) by amoebocytes were measured in two varieties of Asterias rubens occurring in the fjord: The black variety which lives only in the low salinity upper waters (22-26/1000) and the red variety which live both in the upper layer and in the deeper layer characterized by a salinity close to that of seawater (30/1000). The studied immune responses were stimulated in starfish living along the metal pollution gradient according to the contamination of these starfish by cadmium. However, the sensitivity of these responses toward metals appeared to be strongly modulated by the salinity stress. In red starfish living at 30/1000 and transferred up the contamination gradient, the immune responses were inhibited and closely followed the short-term accumulation of metals in the animal organs. Starfish transferred down the gradient did not recover normal immune responses in the short-term and appeared highly sensitive to caging stress. It is suggested that the impact of metals on the immune responses of A. rubens in field conditions occurs in three phases. Short-term inhibitory effects are exerted by a direct action of metals on the immune cells and are followed by a recovery due to the induction of protective mechanisms. Eventually, when these mechanisms are overwhelmed by a long-term contamination, indirect and durable stimulatory effects on the immune responses appear due to a global disruption of the animal physiology.


Subject(s)
Environmental Exposure , Immunity, Cellular/drug effects , Metals, Heavy/toxicity , Starfish/immunology , Water Pollutants/toxicity , Adaptation, Physiological , Animals , Seawater , Sodium Chloride/analysis
14.
Eur J Cell Biol ; 81(7): 413-8, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12160149

ABSTRACT

Amoebocytes are the main effector cells of the echinoderm immune system. In starfishes, a taxon in which bacterial diseases have been rarely reported, amoebocytes are considered to be the only circulating and immune cell type. The present paper addresses the question of amoebocyte differentiation in the starfish Asterias rubens when challenged by bacteria. Starfishes were injected with FITC-coupled bacteria (Micrococcus luteus). Amoebocytes were collected at regular time intervals for 24 h. The cytometric characteristics and the phagocytic activity were studied by flow cytometry. Three amoebocyte groups of different size were identified. The cell concentrations of the two largest and more numerous of these groups (G2 and G3) were modulated by immune stimulation while the group of smallest, less numerous, cells (G1) was unaffected. All of these cell groups were phagocytic but their kinetics of cell activation and bacteria ingestion differed. G1 cells showed the lowest phagocytic activity while G3 cells had the highest and fastest phagocytic activity. Starfish amoebocytes appear to be segregated in three groups, two of them (G2 and G3) being immunomodulated and one of them presenting a very fast reaction to bacteria. It is suggested that the high efficiency of the immune system in starfishes is related to this fast reaction.


Subject(s)
Starfish/immunology , Starfish/microbiology , Animals , Cell Differentiation , Flow Cytometry , Fluorescein-5-isothiocyanate/metabolism , Immune System/cytology , Kinetics , Micrococcus luteus/metabolism , Phagocytosis , Time Factors
15.
Fish Shellfish Immunol ; 12(3): 187-200, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11931015

ABSTRACT

An adapted peroxidase, luminol-enhanced chemiluminescence method in an EDTA-free, Ca++-containing medium is described and used to characterise reactive oxygen species (ROS) production by starfish immunocytes using a standard microplate reader luminometer. ROS production was stimulated by direct interaction of immunocytes with bacteria or bacterial wall components, but not by the soluble stimulant PMA nor the lectin concanavalin A. Produced ROS detected by this method are apparently superoxide anions, hydrogen peroxide and peroxynitrite. Comparison with other chemiluminescence methods indicates that the described method is the only one to detect the stimulation of starfish immunocytes by the Gram-positive bacteria, Micrococcus luteus, a fact that questions previous reports indicating a lack of stimulation by pathogens. The adapted method provides a rapid determination of the overall ROS production, which is suitable for both disease control and immunotoxicological studies in echinoderms.


Subject(s)
Reactive Oxygen Species/analysis , Reactive Oxygen Species/metabolism , Starfish/immunology , Animals , Indicators and Reagents , Kinetics , Luminescent Measurements , Luminol , Oxidation-Reduction , Starfish/cytology
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