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1.
J Res Natl Inst Stand Technol ; 126: 126019, 2021.
Article in English | MEDLINE | ID: mdl-38469438

ABSTRACT

Ultraviolet-C (UV-C) radiation exposure is an attractive option for rapid and consistent disinfection of interior surfaces in aircraft cabins. In this study, fabric and plastic materials commonly used in aircraft cabins were exposed to UV-C radiation to determine their sensitivity to cumulative damage from frequent application. No significant effect on flame retardancy occurred up to 269 J/cm2 dose, and no effect on tensile or tear strength occurred up to 191 J/cm2 . Changes in color or appearance can occur at lower doses. A limit of 40 J/cm2 is proposed to avoid perceptible changes in appearance.

2.
Epilepsy Res ; 166: 106404, 2020 10.
Article in English | MEDLINE | ID: mdl-32731118

ABSTRACT

BACKGROUND: This long-term follow-up (LTFU) trial was conducted to evaluate the long-term safety and tolerability of brivaracetam (BRV) at individualized doses (maximum of 200 mg/day) in patients with focal seizures. The secondary objective was to evaluate the efficacy of BRV over time. METHODS: Two Phase III, randomized, double-blind, historical-controlled conversion-to-monotherapy trials (N01276: NCT00698581; N01306: NCT00699283) were conducted in patients aged ≥16 years with uncontrolled focal seizures. Patients who completed either of these core trials or who met a protocol-defined exit criterion could enter this LTFU trial (N01315; NCT00761774). Patients entered LTFU at a recommended BRV dose of 100 mg/day, with flexible dosing of 50-200 mg/day, as monotherapy or adjunctive therapy; additional AEDs could be prescribed and adapted in dose if clinically indicated. Safety variables included treatment-emergent adverse events (TEAEs). Efficacy variables included duration of continuous monotherapy, reduction in focal seizure frequency and seizure freedom. Safety and efficacy variables were assessed for all patients in the safety set or efficacy set, respectively, regardless of BRV treatment regimen. In addition, a post hoc subgroup analysis was conducted for patients who completed the BRV monotherapy period in either core trial, and entered the LTFU on BRV monotherapy. For this subgroup, TEAEs were summarized by 3-month time intervals over the first 12 months of LTFU. RESULTS: 108 patients were enrolled in the LTFU trial between November 2008 and February 2010. 79 (73.1 %) patients discontinued the LTFU trial, most commonly due to lack of efficacy [37 (34.3 %)] and adverse events [16 (14.8 %)]. At core trial baseline, patients had a median of 6.3 focal seizures/28 days and 53 (49.1 %) had failed ≥5 previous lifetime AEDs. During LTFU, 70 (64.8 %) patients had ≥12 months and 56 (51.9 %) patients had ≥24 months of BRV treatment. TEAEs were reported by 98 (90.7 %) patients; most commonly (≥15 % of patients) convulsion (17.6 %), nasopharyngitis (17.6 %), depression (16.7 %) and fatigue (15.7 %). Median percent reduction from baseline in focal seizure frequency/28 days was 56.8 %. Among 86 patients who completed at least 6 months of treatment, 29 (33.7 %) patients were seizure-free for ≥6 months and 22 (25.6 %) were seizure-free for ≥12 months. 50/108 patients were included in the BRV monotherapy subgroup; 33/50 (66.0 %) patients reported a TEAE in the core trials, while 26/50 (52.0 %), 15/37 (40.5 %), 14/33 (42.4 %) and 9/27 (33.3 %) patients reported any TEAE during LTFU months 1-3, 4-6, 7-9 and 10-12, respectively. In the BRV monotherapy subgroup, the most common TEAEs (≥5% of patients) during LTFU months 1-3 were fatigue [3/50 (6.0 %)] and dizziness [3/50 (6.0 %)]. INTERPRETATION: Results from the LTFU trial support the long-term safety of BRV at individualized doses of up to 200 mg/day as a well-tolerated, and effective treatment for patients with focal seizures. Efficacy analyses indicate that seizure reductions with brivaracetam were generally maintained over time.


Subject(s)
Anticonvulsants/administration & dosage , Internationality , Pyrrolidinones/administration & dosage , Seizures/diagnosis , Seizures/drug therapy , Adult , Anticonvulsants/adverse effects , Dizziness/chemically induced , Double-Blind Method , Fatigue/chemically induced , Female , Follow-Up Studies , Humans , Male , Middle Aged , Pyrrolidinones/adverse effects , Seizures/epidemiology , Treatment Outcome
3.
Ther Innov Regul Sci ; 54(6): 1489-1500, 2020 11.
Article in English | MEDLINE | ID: mdl-32617912

ABSTRACT

Incorporating patient perspectives into clinical studies is recognized as important to the development of high-quality, safe, and effective fit-for-patient medicines. However, no widely accepted methodology to help design more patient-centered studies has been established systematically. TransCelerate Biopharma Inc., a non-profit organization promoting collaboration across biopharmaceutical companies, organized a Patient Experience (PE) Initiative to create tools to intentionally include the patient perspective into the design and implementation of clinical studies. The resulting tools include the Patient Protocol Engagement Toolkit (P-PET), to engage patients early in protocol development, and the Study Participant Feedback Questionnaire (SPFQ), to assess patient experiences during clinical studies. To develop these toolkits, TransCelerate conducted a literature review and identified aspects of clinical studies that patients find either valuable or burdensome, or that affect participation, adherence, and engagement in a clinical study. The concepts identified were refined through elicitation of feedback from patient advisors, clinical study site advisors, and subject matter experts from member companies (MCs) of TransCelerate. This feedback was considered in identifying gaps, defining scientific methodology to understand how to evaluate patients' needs, and developing and refining the P-PET and the SPFQ. As part of the development process, descriptions/drafts of the tools were shared with patients, clinical site advisory groups, MCs, and the US Food and Drug Administration, and then revised. MCs simulated use of the tools, and feedback was incorporated into the final versions of the P-PET and SPFQ prior to public release. The P-PET and SPFQ are available free on the TransCelerate website.


Subject(s)
Patient Participation , Humans , Patient-Centered Care , Research Design , Surveys and Questionnaires , United States , United States Food and Drug Administration
4.
Epilepsia ; 61(4): 636-646, 2020 04.
Article in English | MEDLINE | ID: mdl-32221987

ABSTRACT

OBJECTIVE: To evaluate long-term safety/tolerability of brivaracetam at individualized doses ≤200 mg/d (primary) and maintenance of efficacy over time (secondary) in adults with focal seizures or primary generalized seizures (PGS) enrolled in phase 3, open-label, long-term follow-up trial N01199 (NCT00150800). METHODS: Patients ≥16 years of age who had completed double-blind, placebo-controlled adjunctive brivaracetam trials NCT00175825, NCT00490035, NCT00464269, or NCT00504881 were eligible. Outcomes included safety, efficacy, and quality of life. RESULTS: The safety set included 667 patients (focal seizures, 97.8%; PGS, 2.2%); the efficacy set included 648 patients with focal seizures and 15 patients with PGS. Overall, 49.2% of patients had ≥48 months of exposure. Treatment-emergent adverse events (TEAEs) occurred in 91.2% of all patients (91.3% of focal seizures group), brivaracetam discontinuation due to TEAEs in 14.8%, drug-related TEAEs in 56.7%, and serious TEAEs in 22.8%. The most common TEAEs in the focal seizures group (≥15%) were headache (25.3%) and dizziness (21.9%). Mean changes from baseline in Hospital Anxiety and Depression Scale scores at last value during 2-year evaluation were -0.7 (standard deviation [SD] = 4.3) and -0.2 (SD = 4.4) overall. In the focal seizures group, median reduction from baseline in focal seizure frequency/28 days was 57.3%, 50% responder rate was 55.6%, and 6-month and 12-month seizure freedom rates were 30.3% and 20.3%, respectively. Efficacy outcomes improved by exposure duration cohort and then stabilized through the 108-month cohort. Mean improvement from baseline in Patient-Weighted Quality of Life in Epilepsy Inventory total score (efficacy set) was 5.7 (SD = 16.1, Cohen's d = 0.35) at month 12 and 6.5 (SD = 18.0, Cohen's d = 0.36) at month 24. SIGNIFICANCE: Adjunctive brivaracetam was well tolerated, with a good safety profile in long-term use in adults with epilepsy at individualized doses. Approximately half of the patients remained in the trial at 4 years. Brivaracetam reduced focal seizure frequency versus baseline. Efficacy improved with increasing exposure duration and remained stable through the 9-year cohort.


Subject(s)
Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Pyrrolidinones/therapeutic use , Quality of Life , Adolescent , Adult , Aged , Chemotherapy, Adjuvant , Double-Blind Method , Drug Therapy, Combination , Female , Follow-Up Studies , Humans , Male , Middle Aged , Seizures/drug therapy , Time , Treatment Outcome , Young Adult
5.
Ther Innov Regul Sci ; 54(5): 1001-1009, 2020 09.
Article in English | MEDLINE | ID: mdl-31965539

ABSTRACT

BACKGROUND: Biopharmaceutical companies are piloting patient experience surveys (PES) to help enhance patient satisfaction with clinical studies. However, most PES have been conducted at study close-out, which can hinder recall and responsiveness, and at a limited number of sites, which restricts their applicability to global studies. Our aim was to investigate the feasibility of developing sequential PES, which would be deployed globally, and to provide practical recommendations based on our real-world experience. METHODS: To develop sequential PES (introductory, interim, close-out), we customized a previously developed patient experience close-out survey. Extensive input was gained from multiple stakeholders (e.g., survey experts, patient advisors, psychometricians, clinical trialists, lawyers). To deploy the PES in global studies, we prepared PES-specific ethics committee submissions, training materials (e.g., slides, videos), and PES invitation aids (postcards, digital app reminders). RESULTS: Developing and deploying sequential PES in global clinical studies was feasible. The 3-part online PES (25 to 37 questions per survey) passed health literacy testing. To facilitate benchmarking, the PES included core questions (including a Net Promoter Score question). The PES gained ethics approval and was deployed globally in 2017-2018 in 12 phase 2 and 3 clinical studies in North America, Europe, and the Asia-Pacific. Based on the real-world insights gained and the challenges encountered, we have made recommendations for PES. CONCLUSIONS: Our practical recommendations on the development and deployment of sequential global PES may assist others to implement PES efficiently and effectively, allowing them to gain feedback from patients globally during clinical studies.


Subject(s)
Patient Outcome Assessment , Patient Satisfaction , Asia , Europe , Humans , Surveys and Questionnaires
6.
Epilepsy Res ; 130: 13-20, 2017 02.
Article in English | MEDLINE | ID: mdl-28086164

ABSTRACT

OBJECTIVE: Assess the safety of adjunctive lacosamide for the treatment of uncontrolled primary generalized tonic-clonic seizures in patients (16-65 years) with primary generalized (genetic) epilepsy (PGE). METHODS: An open-label pilot safety study (SP0961; NCT01118949), comprising 12 weeks' historical baseline, 4 weeks' prospective baseline, 3 weeks' titration (target: 400mg/day adjunctive lacosamide) and 6 weeks' maintenance. Patients who continued to the extension study (SP0962; NCT01118962) then received ≤59 weeks of flexible treatment (100-800mg/day lacosamide with flexible dosing of concomitant antiepileptic drugs). The primary outcomes for SP0961 were the mean change (±standard deviation) in absence seizure or myoclonic seizure days per 28days from prospective baseline to maintenance; for SP0962, the incidence of treatment-emergent adverse events (TEAEs) and withdrawals because of TEAEs. RESULTS: Of the 49 patients who enrolled, 40 (82%) completed the pilot study and 9 discontinued (5 because of adverse events). Of the 39 patients who continued to the extension study, 10 discontinued (2 owing to TEAEs) and 29 (74%) completed the study. During the pilot study, patients reported a reduction in mean (±standard deviation) absence and myoclonic seizure days per 28days (-0.37±4.80, -2.19±5.80). Reductions were also observed during the extension study (-2.38±5.54, -2.78±6.43). Five patients in SP0961 and 2 patients in SP0962 experienced TEAEs of new or increased frequency of absence seizures or myoclonic seizures. The most common TEAEs during SP0961 were dizziness (39%) and nausea (27%), and during SP0962 were dizziness (26%) and upper respiratory tract infection (26%). CONCLUSIONS: The safety profile of adjunctive lacosamide was similar to that previously published. Adjunctive lacosamide did not systematically worsen absence or myoclonic seizures, and appears to be well tolerated in patients with PGE.


Subject(s)
Acetamides/therapeutic use , Anticonvulsants/therapeutic use , Seizures/drug therapy , Acetamides/adverse effects , Adolescent , Adult , Aged , Anticonvulsants/adverse effects , Epilepsy, Generalized/drug therapy , Female , Follow-Up Studies , Humans , Lacosamide , Male , Middle Aged , Pilot Projects , Treatment Outcome , Young Adult
7.
Epilepsy Behav ; 52(Pt A): 165-8, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26432008

ABSTRACT

We evaluated nonpsychotic behavioral adverse events (BAEs) in patients receiving levetiracetam (LEV) who switched to brivaracetam (BRV). Patients ≥16 years of age, receiving 2-3 antiepileptic drugs (AEDs), including LEV 1-3g/day, and experiencing BAEs within 16 weeks of LEV treatment initiation, enrolled in an open-label Phase 3b study (NCT01653262) comprising a ≤1-week screening period, an immediate switch from LEV to BRV 200mg/day (without titration), and a 12-week treatment period. The percentages of patients with investigator-assessed clinically meaningful reduction in BAEs, shift in maximum BAE intensity, and change in health-related quality of life (HRQoL) (Patient-Weighted Quality of Life in Epilepsy Inventory-Form 31 [QOLIE-31-P]) were assessed. Of 29 patients enrolled, 26 (89.7%) completed the study. At the end of the treatment period, 27/29 (93.1%) patients switched to BRV had clinically meaningful reductions in BAEs. Physicians reported a reduction in the maximum intensity of primary BAEs in 27/29 (93.1%) patients. Mean change from baseline to Week 12 in QOLIE-31-P total score was 12.1, indicating improved HRQoL. During the treatment period, 23/29 (79.3%) patients reported treatment-emergent adverse events (TEAEs). One patient reported a serious TEAE (suicidal ideation and suicide attempt). Two patients discontinued BRV because of TEAEs. Findings from this small study suggest that patients experiencing BAEs associated with LEV may benefit from switching to BRV.


Subject(s)
Anticonvulsants/adverse effects , Anticonvulsants/therapeutic use , Epilepsy/drug therapy , Epilepsy/psychology , Piracetam/analogs & derivatives , Pyrrolidinones/adverse effects , Pyrrolidinones/therapeutic use , Adolescent , Adult , Epilepsy/complications , Female , Humans , Levetiracetam , Male , Mental Disorders/chemically induced , Mental Disorders/psychology , Middle Aged , Piracetam/adverse effects , Piracetam/therapeutic use , Prospective Studies , Quality of Life , Suicidal Ideation , Suicide, Attempted , Treatment Outcome , Young Adult
8.
Seizure ; 25: 155-9, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25468512

ABSTRACT

PURPOSE: Seizures and antiepileptic drugs (AED) may disrupt sleep patterns in patients with epilepsy, thus evaluation of lacosamide effects on objective and subjective sleep measures is warranted. METHODS: A multicenter, interventional, open-label study (NCT01530386) was conducted in healthy subjects without confounding effects of concomitant AED use, co-morbidities, or disease state to determine whether lacosamide impacts sleep parameters after 22 days of lacosamide exposure. After overnight polysomnography (PSG) to assess baseline parameters, lacosamide was initiated at 100mg/day (50mg twice daily) and increased by 100mg/day weekly to 300 mg/day (the mid-range maintenance dose for adjunctive therapy). The primary variable was change from baseline to post-treatment in wake after sleep onset (WASO). Secondary variables included additional objective sleep measures, subject-reported measures of sleep quality, daytime sleepiness, and tolerability. Change from baseline in WASO was analyzed using the Wilcoxon rank-sum test. RESULTS: A total of 27 subjects received ≥1 dose of lacosamide and 25 subjects completed the study. For WASO, median change from baseline was a 6-min reduction (95% confidence interval: -38, 77.5; p=0.1074) after lacosamide treatment; this was considered not clinically relevant. No clinically relevant changes were observed in any secondary variables. Thirteen subjects (48%) reported a treatment-emergent adverse event, none of which was severe or led to study discontinuation. CONCLUSION: Lacosamide 300 mg/day had no effect on objective or subjective sleep parameters in healthy subjects and was generally well tolerated.


Subject(s)
Acetamides/pharmacology , Anticonvulsants/pharmacology , Sleep/drug effects , Acetamides/adverse effects , Acetamides/pharmacokinetics , Adolescent , Adult , Anticonvulsants/adverse effects , Anticonvulsants/pharmacokinetics , Female , Humans , Lacosamide , Male , Middle Aged , Polysomnography , Sleep/physiology , Young Adult
9.
Eur J Immunol ; 40(6): 1728-37, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20373289

ABSTRACT

Pharmacological modulation is known to temper the immune capacity of DC, enhancing the notion that modulated Ag-bearing DC might be used therapeutically to induce tolerance. We have investigated phenotypic features shared by such DC, and queried their potential to tolerize in different settings. Immature, IL-10, TGF-beta and 1alpha,25-dihydroxyvitamin D(3)-modulated BMDC all induced tolerance to male skin in female TCR transgenic A1.RAG mice, and the modulated DC also tolerized after exposure to the TLR4-ligand LPS. Transcript profiling revealed that this was achieved despite retaining much of the normal LPS-maturation response. No shared tolerance-associated transcripts could be identified. Equivalent BMDC could not tolerize in Marilyn TCR-transgenic mice. Simultaneous presentation of both A1.RAG and Marilyn peptide-Ag (Dby-H2E(k) and Dby-H2A(b)) on immature (C57BL/6JxCBA/Ca) F1 BMDC also only achieved tolerance in A1.RAG mice. Both strains registered Ag, but Foxp3(+) Treg were only induced in A1.RAG mice. In contrast, Marilyn T cells showed greater proliferation and an inflammatory bias, in response to Ag presented by immature F1 BMDC in vitro. In summary, while pharmacological agents can skew DC to reinforce their immature tolerogenic phenotype, the outcome of presentation is ultimately an integrated response including T-cell-intrinsic components that can over-ride for immune activation.


Subject(s)
Dendritic Cells/immunology , Immune Tolerance/immunology , Animals , Antigen Presentation/immunology , Cell Separation , Female , Flow Cytometry , Lymphocyte Activation/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Oligonucleotide Array Sequence Analysis , Polymerase Chain Reaction , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/immunology , T-Lymphocytes/immunology
10.
BMC Health Serv Res ; 8: 264, 2008 Dec 18.
Article in English | MEDLINE | ID: mdl-19094222

ABSTRACT

BACKGROUND: Little is known about the relationship between types of healthcare providers and outcomes in patients with epilepsy. This study compares the relative effects of provider type (epileptologist vs. other neurologist) and pharmacologic treatment (newer vs. older antiepileptic drugs) on seizure control in patients with epilepsy. METHODS: We conducted a retrospective study of patients with medication-resistant epilepsy. Consecutive charts of 200 patients were abstracted using a standard case report form. For each patient, data included seizure frequency and medication use prior to, and while being treated by an epileptologist. Changes in seizure frequency were modeled using a generalized linear model. RESULTS: After transferring care from a general neurologist to specialized epilepsy center, patients experienced fewer seizures (p < 0.001) and were more frequently seizure-free (p < 0.001). The improved seizure control was not related to treatment with newer vs. older antiepileptic drugs (p = 0.305). CONCLUSION: Our findings suggest an association between subspecialty epilepsy care and improved seizure control in patients with medication-resistant epilepsy. Further research should prospectively determine whether patients with medication-resistant epilepsy would benefit from being routinely referred to an epilepsy specialist.


Subject(s)
Anticonvulsants/therapeutic use , Clinical Competence , Drug Resistance , Seizures/drug therapy , Adult , Aged , Aged, 80 and over , Cohort Studies , Female , Humans , Male , Middle Aged , Neurology , Practice Patterns, Physicians' , Retrospective Studies , Young Adult
11.
J Immunol ; 179(2): 967-76, 2007 Jul 15.
Article in English | MEDLINE | ID: mdl-17617588

ABSTRACT

Transplants tolerated through a process known as infectious tolerance evoke continuous recruitment of regulatory T (Treg) cells that are necessary to maintain the unresponsive state. This state is maintained long-term and requires continuous Ag exposure. It is not known, however, whether infectious tolerance operates through sustained recruitment of pre-existing regulatory cells, induction of regulatory cells, or both. Using mice deficient in natural Treg cells, we show here that quiescent donor dendritic cells (DC) laden with histocompatibility Ag can induce Treg cells de novo that mediate transplantation tolerance. In contrast, fully activated DC fail to do so. These findings suggest that DC incapable of delivering full activation signals to naive T cells may favor their polarization toward a regulatory phenotype. Furthermore, they suggest a role for quiescent endogenous DC in the maintenance of the tolerant state.


Subject(s)
Dendritic Cells/immunology , Lymphocyte Activation/immunology , T-Lymphocyte Subsets/immunology , T-Lymphocytes, Regulatory/immunology , Transplantation Tolerance/immunology , Animals , Enzyme-Linked Immunosorbent Assay , Female , Flow Cytometry , Gene Expression , Gene Expression Regulation/immunology , Mice , Mice, Transgenic , Oligonucleotide Array Sequence Analysis , Reverse Transcriptase Polymerase Chain Reaction , Skin Transplantation/immunology
12.
Neurocrit Care ; 7(2): 140-7, 2007.
Article in English | MEDLINE | ID: mdl-17607530

ABSTRACT

INTRODUCTION: Levetiracetam (LEV) is used in the setting of acute brain injury for seizure treatment or prophylaxis but its safety and efficacy in this setting is unknown. METHOD: We retrospectively analyzed the patterns of use and safety/efficacy of LEV in 379 patients treated in the neuroscience intensive care unit (NSICU). We extracted from the charts clinical data including diagnosis, AED therapy before and during stay in the NSICU, complications of treatment, length of stay, and clinical outcomes (improvement, Glasgow Coma Scale, and death). We analyzed the data using binary and ordered (multi-category) logistic regression. RESULTS: Overall, our findings are that phenytoin used prior to the NSICU admission was frequently replaced with LEV monotherapy (P < 0.001). Patients treated with LEV monotherapy when compared to other AEDs had lower complication rates and shorter NSICU stays. Older patients and patients with brain tumors or strokes were preferentially treated with LEV for prevention and/or management of seizures (all P < or = 0.014). DISCUSSION: The results of this study suggest that LEV is a frequently used AED in the setting of acute brain injury and that it may be a desirable alternative to phenytoin. Prospective studies evaluating the long-term safety, efficacy and outcomes of LEV in this setting are indicated.


Subject(s)
Anticonvulsants/therapeutic use , Brain Diseases/drug therapy , Critical Illness , Piracetam/analogs & derivatives , Acute Disease , Adolescent , Adult , Aged , Aged, 80 and over , Brain Diseases/mortality , Brain Neoplasms/drug therapy , Brain Neoplasms/mortality , Cerebral Hemorrhage/drug therapy , Cerebral Hemorrhage/mortality , Comorbidity , Epilepsy/drug therapy , Epilepsy/mortality , Humans , Intensive Care Units , Length of Stay , Levetiracetam , Middle Aged , Piracetam/therapeutic use , Retrospective Studies , Stroke/drug therapy , Stroke/mortality , Treatment Outcome
13.
Immunol Rev ; 213: 239-55, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16972908

ABSTRACT

Immune privilege was originally believed to be associated with particular organs, such as the testes, brain, the anterior chamber of the eye, and the placenta, which need to be protected from any excessive inflammatory activity. It is now becoming clear, however, that immune privilege can be acquired locally in many different tissues in response to inflammation, but particularly due to the action of regulatory T cells (Tregs) induced by the deliberate therapeutic manipulation of the immune system toward tolerance. In this review, we consider the interplay between Tregs, dendritic cells, and the graft itself and the resulting local protective mechanisms that are coordinated to maintain the tolerant state. We discuss how both anti-inflammatory cytokines and negative costimulatory interactions can elicit a number of interrelated mechanisms to regulate both T-cell and antigen-presenting cell activity, for example, by catabolism of the amino acids tryptophan and arginine and the induction of hemoxygenase and carbon monoxide. The induction of local immune privilege has implications for the design of therapeutic regimens and the monitoring of the tolerant status of patients being weaned off immunosuppression.


Subject(s)
Graft Rejection/immunology , T-Lymphocytes, Regulatory/immunology , Transplantation Tolerance/physiology , Animals , Humans , Indoleamine-Pyrrole 2,3,-Dioxygenase/physiology
14.
Proc Natl Acad Sci U S A ; 100(25): 15059-64, 2003 Dec 09.
Article in English | MEDLINE | ID: mdl-14608036

ABSTRACT

Recently, agonist antibodies to glucocorticoid-induced tumor necrosis factor receptor (GITR) (tumor necrosis factor receptor superfamily 18) have been shown to neutralize the suppressive activity of CD4+CD25+ regulatory T cells. It was anticipated that this would be the role of the physiological ligand. We have identified and expressed the gene for mouse GITR ligand and have confirmed that its interaction with GITR reverses suppression by CD4+CD25+ T cells. It also, however, provides a costimulatory signal for the antigen-driven proliferation of naïve T cells and polarized T helper 1 and T helper 2 clones. RT-PCR and mAb staining revealed mouse GITR ligand expression in dendritic cells, macrophages, and B cells. Expression was controlled by the transcription factor NF-1 and potentially by alternative splicing of mRNA destabilization sequences.


Subject(s)
Carrier Proteins/metabolism , T-Lymphocytes/metabolism , Alternative Splicing , Amino Acid Sequence , Animals , Antibodies, Monoclonal/metabolism , Base Sequence , CD4 Antigens/biosynthesis , CD4-Positive T-Lymphocytes/immunology , Cell Division , Cell Line , Cloning, Molecular , DNA, Complementary/metabolism , Dose-Response Relationship, Drug , Humans , Immunoblotting , Jurkat Cells , Ligands , Luciferases/metabolism , Macrophages/metabolism , Mice , Models, Genetic , Molecular Sequence Data , Neurofibromin 1/metabolism , Plasmids/metabolism , RNA, Messenger/metabolism , Receptors, Interleukin-2/biosynthesis , Recombinant Proteins/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Amino Acid , Time Factors , Transcription, Genetic , Transfection , Tumor Necrosis Factors
15.
Immunol Rev ; 196: 109-24, 2003 Dec.
Article in English | MEDLINE | ID: mdl-14617201

ABSTRACT

Transplantation tolerance can be induced in adult rodents using monoclonal antibodies against coreceptor or costimulation molecules on the surface of T cells. There are currently two well-characterized populations of T cells, demonstrating regulatory capacity: the "natural" CD4+CD25+ T cells and the interleukin (IL)-10-producing Tr1 cells. Although both types of regulatory T cells can induce transplantation tolerance under appropriate conditions, it is not clear whether either one plays any role in drug-induced dominant tolerance, primarily due to a lack of clear-cut molecular or functional markers. Similarly, although dendritic cells (DCs) can be pharmacologically manipulated to promote tolerance, the phenotype of such populations remains poorly defined. We have used serial analysis of gene expression (SAGE) with 29 different T-cell and antigen-presenting cell libraries to identify gene-expression signatures associated with immune regulation. We found that independently derived, regulatory Tr1-like clones were highly concordant in their patterns of gene expression but were quite distinct from CD4+CD25+ regulatory T cells from the spleen. DCs that were treated with the tolerance-enhancing agents IL-10 or vitamin D3 expressed a gene signature reflecting a functional specification in common with the most immature DCs derived from embryonic stem cells.


Subject(s)
Dendritic Cells/immunology , Dendritic Cells/metabolism , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Transplantation Tolerance/immunology , Animals , Antigens, CD/immunology , Gene Expression Profiling , Humans
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