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1.
Otolaryngol Clin North Am ; 57(2): 265-278, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37833102

RESUMO

Aspirin-exacerbated respiratory disease (AERD) is a subtype of chronic rhinosinusitis with polyps (CRSwNP) and asthma with higher recurrence of nasal polyps after surgery and severe asthma. Patients with CRSwNP and asthma should be screened for AERD by detailed history of aspirin/nonsteroidal anti-inflammatory drug reactions and review of medications that may mask aspirin reaction or directly by aspirin challenge. Treatment of AERD may require more intensive therapy, including endoscopic sinus surgery, daily aspirin therapy, leukotriene modifiers, or biologics.


Assuntos
Asma Induzida por Aspirina , Asma , Pólipos Nasais , Rinite , Sinusite , Humanos , Rinite/induzido quimicamente , Rinite/terapia , Asma Induzida por Aspirina/diagnóstico , Asma Induzida por Aspirina/terapia , Aspirina/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Pólipos Nasais/terapia , Sinusite/induzido quimicamente , Sinusite/terapia , Doença Crônica
2.
J Anesth ; 37(5): 741-748, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37466804

RESUMO

PURPOSE: Patients with mastocytosis have an increased risk of anaphylaxis during surgical procedures with general anesthesia. Therefore, we reviewed the anesthesia course of a large cohort of patients with mastocytosis. METHODS: We retrospectively reviewed adult and pediatric patients with mastocytosis who underwent surgical procedures with general anesthesia at Mayo Clinic from January 1, 2000, through June 30, 2021. We also included any procedures with general anesthesia that occurred during the 3-year period preceding mastocytosis diagnosis and designated the patients who underwent these procedures as having an unknown diagnosis at the time of their surgical procedure. We analyzed whether patients received chronic antimediator treatment for mastocytosis and/or prophylactic medications before the procedures. We also determined whether medications indicative of mastocytosis-related adverse events were intraoperatively administered. RESULTS: We identified 113 patients who underwent 219 procedures during the study period; 25 procedures were performed before mastocytosis diagnosis. Of 194 procedures in patients with known mastocytosis, patients received chronic antimediator therapy and/or perioperative prophylactic medications for 178 (91.8%) procedures. Among these procedures, 10 were potentially complicated by mast cell activation, which was inferred from administration of inhaled albuterol (n = 3) or intravenous diphenhydramine (n = 8). In addition, there was only one case of intraoperative anaphylaxis which occurred in a patient who underwent anesthesia before mastocytosis diagnosis and therefore did not receive prophylaxis. CONCLUSION: Intraoperative anaphylaxis can be the first presenting sign of mastocytosis. Patients with mastocytosis who received chronic antimediator therapy and/or preoperative prophylactic medications had an uneventful surgical course.


Assuntos
Anafilaxia , Mastocitose , Adulto , Humanos , Criança , Anafilaxia/etiologia , Estudos Retrospectivos , Mastocitose/complicações , Mastocitose/cirurgia , Mastocitose/diagnóstico , Anestesia Geral/efeitos adversos , Albuterol
3.
Otolaryngol Clin North Am ; 56(1): 11-22, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36410988

RESUMO

The concept of a unified airway posits that pathology affects the respiratory tract in a continuum and that disease in one part of the respiratory tract may be associated with or directly or indirectly affect the function of a different part. Transcriptomic analysis has shown 91% homology between the genes expressed in the upper and the lower airway. Approaching inflammatory airway disorders using the unified airway hypothesis allows for a better clarification of disease process and provides a detailed and a high-level overview of dysfunction. There are several tools available to the clinician to use to subtype and diagnose accurately the abnormal pathways operating in inflammatory airway disorders. These tools include clinical history, physical examination findings, imaging (computed tomography and MRI), allergy and laboratory testing, pulmonary function testing (PFT), and tissue histopathology. Tests can be categorized based on platform, by specimen, or the marker being studied.


Assuntos
Hipersensibilidade , Humanos , Tomografia Computadorizada por Raios X
4.
Otolaryngol Clin North Am ; 56(1): 107-124, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36283868

RESUMO

Aspirin-exacerbated respiratory disease (AERD) is characterized by abnormal arachidonic acid metabolism leading to chronic rhinosinusitis with nasal polyposis (CRSwNP), asthma, and upper and/or lower respiratory symptoms after ingestion of cyclooxygenase-1 inhibiting nonsteroidal antiinflammatory drugs. Diagnosis is clinical and may involve an aspirin challenge. Inflammatory biomarkers may be useful for diagnosis and treatment monitoring. Conventional medical management for asthma and CRSwNP is often inadequate. Endoscopic sinus surgery followed by continued medical management with or without aspirin desensitization frequently improves symptoms and objective disease measures. Biological agents targeting eosinophilic inflammation are promising alternatives to conventional management.


Assuntos
Asma Induzida por Aspirina , Asma , Pólipos Nasais , Rinite , Sinusite , Humanos , Rinite/induzido quimicamente , Rinite/diagnóstico , Rinite/terapia , Asma Induzida por Aspirina/diagnóstico , Asma Induzida por Aspirina/terapia , Sinusite/induzido quimicamente , Sinusite/terapia , Sinusite/diagnóstico , Pólipos Nasais/induzido quimicamente , Pólipos Nasais/terapia , Aspirina/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Doença Crônica
5.
Mayo Clin Proc Innov Qual Outcomes ; 6(1): 69-76, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35024565

RESUMO

OBJECTIVE: To estimate the potential risk for a future postmarket black box warning (BBW) of US Food and Drug Administration (FDA)-approved monoclonal antibodies (mAbs) because of the importance for medical clinicians to understand mAb risks and benefits, including unknown future risks, especially for recently approved mAbs. METHODS: The complete dates of the study were March 16, 2020, through May 12, 2021. We searched the FDALabel database online and reviewed the scientific literature to determine current and previous FDA-approved mAbs as of March 2020. The BBWs and initial FDA-issued safety warnings were identified. The BBWs were categorized as premarket or postmarket. For mAbs with specific postmarket BBWs, previous FDA labels were evaluated to identify the presence or absence of an initial corresponding specific FDA warning. RESULTS: In March 2020, a total of 83 mAbs had FDA approval; 33 had BBWs (27 premarket and 13 postmarket BBWs). Of these 33 mAbs, 55 individual specific BBWs existed (36 premarket and 19 postmarket specific warnings). On average, the specific BBWs occurred in the postmarket period at a rate of 3.4% (19/562) per year. Most (73.7%; 14/19) specific postmarket BBWs were preceded by an FDA warning in a median time of 3.61 (interquartile range, 1.36-5.78) years. Specific postmarket BBWs not preceded by a specific FDA product label warning occurred at an average rate of 0.9% (5/562) per year. CONCLUSION: Specific postmarket BBWs occurred in FDA-approved mAbs at a rate of 3.4% per year. Specific postmarket BBWs not preceded by a specific FDA product label warning had a rate of 0.9% per year.

6.
Allergy Asthma Proc ; 42(4): 267-273, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34187619

RESUMO

Background: It remains unclear if asthma is a risk factor associated with worse outcomes among patients with coronavirus disease 2019 (COVID-19). Methods: We performed a comprehensive database search for studies published from January 1, 2019, to October 2, 2020. We included studies that evaluated outcomes among patients with COVID-19 and underlying asthma. Outcomes of interest included the need for hospitalization, length of hospitalization, intensive care unit (ICU) admission, and death. The meta-analysis was conducted by using random-effects methodology. Results: A total of 389 studies were identified through data base searches. After abstract and full-text screening, 16 observational studies with 92,275 patients were included in the analysis. Of the 16 studies, 15 were retrospective and 1 was a prospective cohort study. The average age was 39.6 years, with 48% female patients. Six of the studies included pediatric patients, and one of these studies only evaluated pediatric patients. One study only evaluated pregnant patients. Among patients with COVID-19, the presence of asthma was not associated with any significant increase in risk of hospitalization (odds ratio [OR] 1.46 [95% confidence interval {CI}, 0.29-7.28]), length of hospitalization (1.59 days [-0.55 to 3.74]), ICU admission (OR 1.65 [95% CI, 0.56-4.17]), or death (OR 0.73 [95% CI, 0.38-1.40]). The overall risk of bias of the included studies was high. Conclusion: Among the patients with COVID-19, asthma did not seem to significantly increase the risk of hospitalization, length of hospitalization, ICU admission, or death.


Assuntos
Asma/terapia , COVID-19/terapia , Hospitalização , Adulto , Idoso , Asma/diagnóstico , Asma/mortalidade , COVID-19/diagnóstico , COVID-19/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Prognóstico , Medição de Risco , Fatores de Risco , Fatores de Tempo , Adulto Jovem
7.
J Asthma ; 58(8): 1077-1086, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32315558

RESUMO

OBJECTIVE: While a single but truncated ICD code (493) had been widely used for identifying asthma in asthma care and research, it significantly under-identifies asthma. We aimed to develop and validate a diagnostic codes-based algorithm for identifying asthmatics using Predetermined Asthma Criteria (PAC) as the reference. METHODS: This is a retrospective cross-sectional study which utilized two different coding systems, the Hospital Adaptation of the International Classification of Diseases, Eighth Revision (H-ICDA) and the International Classification of Diseases, Ninth Revision (ICD-9). The algorithm was developed using two population-based asthma study cohorts, and validated in a validation cohort, a random sample of the 1976-2007 Olmsted County Birth Cohort. Performance of the diagnostic codes-based algorithm for ascertaining asthma status against manual chart review for PAC (gold standard) was assessed by determining both criterion and construct validity. RESULTS: Among eligible 267 subjects of the validation cohort, 50% were male, 70% white, and the median age at last follow-up was 17 (interquartile range, 8.7-24.4) years. Asthma prevalence by PAC through manual chart review was 34%. Sensitivity and specificity of the codes-based algorithm for identifying asthma were 82% and 98% respectively. Associations of asthma-related risk factors with asthma status ascertained by the code-based algorithm were similar to those by the manual review. CONCLUSIONS: The diagnostic codes-based algorithm for identifying asthmatics improves accuracy of identification of asthma and can be a useful tool for large scale studies in a setting without automated chart review capabilities.


Assuntos
Algoritmos , Asma/diagnóstico , Adolescente , Adulto , Criança , Estudos Transversais , Conjuntos de Dados como Assunto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
8.
Cancer Chemother Pharmacol ; 86(3): 375-382, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32778906

RESUMO

PURPOSE: Temozolomide is the most effective chemotherapy for malignant glioma. Hypersensitivity requiring interruption of therapy may significantly impact patient survival. We have successfully employed temozolomide desensitization followed by metronomic dosing of temozolomide. Our purpose was to report patient characteristics and outcomes in patients with glioma (Grade 2-4) and temozolomide hypersensitivity managed by desensitization and metronomic dosing. METHODS: We performed an observational study of 15 patients at Mayo Clinic (Rochester) with a diagnosis of glioma who underwent temozolomide desensitization with subsequent metronomic dosing from May 2012 to January 2017. We calculated overall and progression-free survival using the Kaplan-Meier method, and log-rank analyses to assess for differences in survival by WHO Grade or treatment initiation. RESULTS: Median age at time of desensitization was 49.3 years (26.8-64.7 years). Median follow-up after desensitization was 35.5 months. One patient (6.7%) was unable to resume temozolomide due to recurrent allergy. The median time from first desensitization to discontinuation of metronomic temozolomide was 4.2 months (0-15.2 months). Median OS and PFS for the whole sample were 181.7 months and 44.9 months. For Grade 4, OS was 100% at 1 year, 40% at 3 years, 20% at 5 years; and PFS was 60% at 1 year, 40% at 3 years, and 20% at 5 years. CONCLUSION: Our results suggest that rapid-desensitization followed by metronomic temozolomide should be considered in patients with glioma who experience hypersensitivity. This strategy provides comparable outcomes to therapy with standard protocols, with the majority of patients able to tolerate temozolomide after desensitization with favorable disease control.


Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Dessensibilização Imunológica/métodos , Glioma/tratamento farmacológico , Hipersensibilidade/tratamento farmacológico , Temozolomida/administração & dosagem , Administração Metronômica , Adulto , Idoso , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Quimioterapia Adjuvante , Feminino , Seguimentos , Glioma/imunologia , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
9.
Int Forum Allergy Rhinol ; 8(9): 1047-1051, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29851243

RESUMO

BACKGROUND: Revision surgery rates following endoscopic sinus surgery (ESS) range between 7% and 50% and are influenced by many factors. This study investigates ESS outcomes for chronic rhinosinusitis (CRS) subtypes. METHODS: Retrospective review of adult CRS patients undergoing ESS with a single surgeon (2010-2015) was conducted. Outcomes were analyzed by CRS subtypes. RESULTS: ESS was performed in 424 CRS patients (CRS with nasal polyps [CRSwNP], n = 170; CRS without polyps [CRSsNP], n = 254). Most patients (309; 72.9%) could not be specifically subtyped; 115 (27.1%) were subtyped as follows: aspirin-exacerbated respiratory disease (AERD), n = 47 (11.1%); allergic fungal sinusitis (AFS), n = 39 (9.2%); immunodeficiency, n = 21 (5.0%); granulomatosis with polyangiitis (GPA), n = 5 (1.2%); and eosinophilic granulomatosis with polyangiitis (EGPA), n = 3 (0.7%). All subgroups experienced clinically meaningful reduction in postoperative 22-item Sino-Nasal Outcome Test (SNOT-22) scores. At median follow-up of 28 months (interquartile range [IQR], 10-47 months), 19 patients (4%) underwent revision ESS (CRSwNP, n = 6; CRSsNP, n = 13). Revision ESS rates were 3.5% and 5.1% for CRSwNP and CRSsNP, respectively. Revision ESS rate for subtypes were: AERD 2%; AFS 2%; immunodeficiency 14%; GPA 40%; EGPA 0%; and "all other CRS" 4% at median follow-up duration of 36, 28, 41, 37, 44, and 26 months, respectively. CONCLUSION: All CRS subtypes demonstrated clinically meaningful improvement in postoperative SNOT-22 scores following ESS. Our overall revision ESS rate was 4% (3.5% in CRSwNP). AFS, AERD, and EGPA groups demonstrated low revision rates, while immunodeficiency and GPA patients required more revision surgery. A contemporary understanding of CRSwNP subtypes facilitated surgical and medical strategies in improving outcomes for AERD, AFS, and EGPA patients. CRSsNP subtypes with immunodeficiency and GPA merit further investigation to optimize outcomes.


Assuntos
Seios Paranasais/cirurgia , Reoperação/estatística & dados numéricos , Rinite/cirurgia , Sinusite/cirurgia , Adulto , Idoso , Doença Crônica , Endoscopia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/classificação , Pólipos Nasais/patologia , Pólipos Nasais/cirurgia , Seios Paranasais/patologia , Estudos Retrospectivos , Rinite/classificação , Rinite/patologia , Fatores de Risco , Sinusite/classificação , Sinusite/patologia , Resultado do Tratamento
10.
Int Forum Allergy Rhinol ; 8(7): 797-805, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29437297

RESUMO

BACKGROUND: Endotypic and prognosticating features of chronic rhinosinusitis without nasal polyposis (CRSsNP) are poorly understood. Our objectives were to use an unbiased symptom-based approach to: (1) study symptoms, clinical and endotypic features; and (2) identify features predicating outcomes from endoscopic sinus surgery (ESS). METHODS: Clinical, computed tomography (CT), histopathology, and 22-item Sino-Nasal Outcome Test (SNOT-22) data was collected on 146 adult CRSsNP patients who underwent ESS. Unsupervised network modeling of presurgical SNOT-22 scores was performed to classify symptom-based clusters. Subject characteristics and post-ESS SNOT-22 scores were compared between clusters. RESULTS: Baseline characteristics of the subject population were as follows: females, 56.2%; revision ESS status in 35%; asthma prevalence, 32.6%; median Lund-Mackay CT score, 8; and median SNOT-22 total score, 43. Network mapping and unsupervised clustering of preoperative SNOT-22 scores revealed 4 clusters: (A) severely burdened with high scores in all 4 subdomains; (B) moderately burdened with high scores in the rhinologic subdomain; (C) moderately burdened with high scores in psychological-sleep subdomains; and (D) mildly burdened. The number of previous ESS and asthma prevalence differed significantly between clusters; CT scores were similar. Asthma burden and tissue eosinophilia were greatest in cluster A (p = 0.03). All groups showed significant improvement at 3 months post-ESS (p < 0.0001). At 6 months, patients in cluster C tended to worsen. CONCLUSION: SNOT-22-based network modeling of CRSsNP patients yielded 4 clusters with distinct features. Asthma prevalence and tissue eosinophilia were highest in the cluster with highest SNOT-22 scores. All patients showed significant improvement from ESS at 3 months; those with high sleep-psychosocial symptoms tended to show worsening at 6 months.


Assuntos
Asma/epidemiologia , Pólipos Nasais/diagnóstico , Rinite/diagnóstico , Sinusite/diagnóstico , Transtornos do Sono-Vigília/epidemiologia , Adulto , Idoso , Doença Crônica , Análise por Conglomerados , Eosinofilia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Prognóstico , Rinite/epidemiologia , Sinusite/epidemiologia , Inquéritos e Questionários , Estados Unidos
11.
Int Forum Allergy Rhinol ; 6(9): 896-905, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27080452

RESUMO

BACKGROUND: Women electing endoscopic sinus surgery (ESS) for chronic rhinosinusitis (CRS) report higher symptom burden but have lower computed tomography (CT) scores. Gender-specific analysis of outcomes from ESS therefore merits further study. The objective of this work was to study gender-specific differences in outcomes from ESS for CRS by analyzing preoperative and postoperative 22-item Sino-Nasal Outcome Test (SNOT-22) scores. METHODS: Data from adult CRS patients electing ESS (2011-2013) were retrospectively collected. SNOT-22 total, rhinologic/nonrhinologic subdomain, and individual item scores were analyzed for gender-specific differences. RESULTS: Two hundred and forty-eight patients met study criteria (mean age 55.4 years; 49.6% female). Preoperatively, mean Lund-Mackay CT score was 11.1; average total SNOT-22 score was 41.9. Compared to men, women had lower CT score (10.2 vs 12.0; p = 0.004) but higher total SNOT-22 score (44.7 vs 39.1; p = 0.02). Both genders showed significant improvement in total SNOT-22 scores at 3, 6, 12, and 24 months following ESS (p < 0.001), with largely similar slopes of improvement. The greatest improvement occurred at 3 months (SNOT-22 decreased by 25.4 points), with stable improvement after 12 months (SNOT-22 decreased by 21.3 points). Higher total SNOT-22 scores in females were noted preoperatively and until 6 months post-ESS; these were driven by rhinologic and nonrhinologic-otolaryngic subdomain items. No gender differences in anxiety/depression prevalence or psychological subdomain scores were noted preoperatively or postoperatively. CONCLUSION: Both male and female CRS patients showed significant and durable symptom relief following ESS. Women reported higher symptom burden prior to surgery, and in the early postoperative period. However, after 1-year post-ESS, both genders showed similar symptom scores. The trend and magnitude of improvement were similar in both genders.


Assuntos
Pólipos Nasais/cirurgia , Seios Paranasais/cirurgia , Rinite/cirurgia , Sinusite/cirurgia , Doença Crônica , Endoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
12.
Asia Pac Allergy ; 5(1): 47-50, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25653920

RESUMO

Severe intraoperative hypotension has been reported in patients on angiotensin-converting enzyme inhibitors and angiotensin II receptor subtype 1 antagonists. We describe a patient on lisinopril who developed refractory intraoperative hypotension associated with increased serum tryptase level suggesting mast cell activation (allergic reaction). However, allergology workup ruled out an allergic etiology as well as mastocytosis, and hypotension recalcitrant to treatment was attributed to uninterrupted lisinopril therapy. Elevated serum tryptase was attributed to our patient's chronic renal insufficiency.

13.
J Immunol ; 190(12): 6004-14, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23686493

RESUMO

Dendritic cells (DCs) have been shown to play a major role in oral tolerance, and this function has been associated with their ability to produce anti-inflammatory cytokines and to induce suppressive regulatory T cells. In this study, we demonstrate that upon oral administration of Ag, lamina propia (LP) DCs engage specific T cells and acquire a novel mechanism by which they transfer tolerance against diverse T cell specificities. Indeed, when Ig-myelin oligodendrocyte glycoprotein (MOG) carrying the MOG(35-55) epitope was orally administered into either T cell-sufficient or -deficient mice, only the T cell-sufficient hosts yielded CD8α(+) and CD8α(-) LP DCs that were able to transfer tolerance to a variety of MHC class II-restricted effector T cells. Surprisingly, these LP DCs upregulated programmed cell death ligand 1 during the initial interaction with MOG-specific T cells and used this inhibitory molecule to suppress activation of T cells regardless of Ag specificity. Furthermore, oral Ig-MOG was able to overcome experimental autoimmune encephalomyelitis induced with CNS homogenate, indicating that the DCs are able to modulate disease involving diverse T cell specificities. This previously unrecognized attribute potentiates DCs against autoimmunity.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Células Dendríticas/imunologia , Tolerância Imunológica/imunologia , Imunidade nas Mucosas/imunologia , Mucosa/imunologia , Administração Oral , Transferência Adotiva , Animais , Autoantígenos/imunologia , Autoimunidade/imunologia , Separação Celular , Encefalomielite Autoimune Experimental/imunologia , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Imunidade Inata/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Glicoproteína Mielina-Oligodendrócito/administração & dosagem , Glicoproteína Mielina-Oligodendrócito/imunologia , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/imunologia
14.
J Immunol ; 187(8): 3979-86, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21911603

RESUMO

The cell dynamics associated with induction of peripheral T cell tolerance remain largely undefined. In this study, an in vivo model was adapted to two-photon microscopy imaging, and T cell behavior was analyzed on tolerogen-induced modulation. FcγR-deficient (FcγR(-/-)) mice were unable to resist or alleviate experimental allergic encephalomyelitis when treated with Ig-myelin oligodendrocyte glycoprotein (MOG) tolerogen, an Ig carrying the MOG35-55 peptide. However, when FcγR(+/+) dendritic cells (DCs) are adoptively transferred into FcγR(-/-) mice, uptake and presentation of Ig-MOG occurs and the animals were able to overcome experimental allergic encephalomyelitis. We then fluorescently labeled FcγR(+/+) DCs and 2D2 MOG-specific TCR-transgenic T cells, transferred them into FcγR(-/-) mice, administered Ig-MOG, and analyzed both T cell-DC contact events and T cell motility. The results indicate that tolerance takes place in lymphoid organs, and surprisingly, the T cells do not become anergic but instead have a Th2 phenotype. The tolerant Th2 cells displayed reduced motility after tolerogen exposure similar to Th1 cells after immunization. However, the Th2 cells had higher migration speeds and took longer to exhibit changes in motility. Therefore, both Th1 immunity and Th2 tolerance alter T cell migration on Ag recognition, but the kinetics of this effect differ among the subsets.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Tolerância Imunológica/imunologia , Subpopulações de Linfócitos T/imunologia , Transferência Adotiva , Animais , Separação Celular , Quimiotaxia de Leucócito/imunologia , Células Dendríticas/imunologia , Encefalomielite Autoimune Experimental/patologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Glicoproteína Associada a Mielina/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia
15.
J Immunol ; 181(1): 73-80, 2008 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-18566371

RESUMO

Lately, it has become clear that regulatory T cells (Tregs) play a major role in the maintenance of peripheral tolerance and control of autoimmunity. Despite these critical functions, the process underlying the development of Tregs remains largely undefined. Herein, altered peptide ligand (APL) variants derived from the proteolipid protein-1 (PLP1) epitope were expressed on immunoglobulins (Igs) and the resulting Ig-APLs were used to deliver the APLs from mother to fetus through the maternal placenta to influence thymic T cell selection. This delivery system was then adapted to the SJL/J mouse, a strain that expresses only the DM20 form of PLP, which lacks the dominant PLP1 epitope in the thymus during fetal and neonatal development. This model, which restores thymic T cell selection for PLP1, was then used to determine whether affinity plays a role in the development of Tregs. The findings show that fetal exposure to low-affinity peptide ligand was unable to drive development of Tregs while variants with higher affinity to the TCR resulted in significant seeding of the periphery with mature, naive Tregs. Thus, contrary to pathogenic T cells, Tregs require avid TCR-ligand interaction to undergo thymic development and maturation.


Assuntos
Diferenciação Celular/imunologia , Feto/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Animais , Encefalomielite Autoimune Experimental/imunologia , Imunidade Inata/imunologia , Imunoglobulinas/imunologia , Ligantes , Contagem de Linfócitos , Camundongos
16.
J Immunol ; 180(3): 1508-16, 2008 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-18209046

RESUMO

A number of Ag-specific approaches have been developed that ameliorate experimental allergic encephalomyelitis (EAE), an animal model for the human autoimmune disease multiple sclerosis. Translation to humans, however, remains a consideration, justifying the search for more insight into the mechanism underlying restoration of self-tolerance. Ig-proteolipid protein (PLP) 1 and Ig-myelin oligodendrocyte glycoprotein (MOG) are Ig chimeras carrying the encephalitogenic PLP 139-151 and MOG 35-55 amino acid sequence, respectively. Ig-PLP1 ameliorates EAE in SJL/J (H-2(s)) mice while Ig-MOG modulates the disease in C57BL/6 (H-2(b)) animals. In this study, we asked whether the chimeras would suppress EAE in F(1) mice expressing both parental MHC alleles and representing a polymorphism with more relevance to human circumstances. The results show that Ig-MOG modulates both PLP1 and MOG peptide-induced EAE in the F(1) mice, whereas Ig-PLP1 counters PLP1 EAE but exacerbates MOG-induced disease. This in trans aggravation of MOG EAE by Ig-PLP1 operates through induction of PLP1-specific T cells producing IL-5 that sustained inhibition of MOG-specific Abs leading to exacerbation of EAE. Thus, in trans T cell tolerance, which should be operative in polymorphic systems, can aggravate rather than ameliorate autoimmunity. This phenomenon possibly takes place through interference with protective humoral immunity.


Assuntos
Autoanticorpos/imunologia , Quimera/imunologia , Encefalomielite Autoimune Experimental/imunologia , Tolerância Imunológica , Linfócitos T/imunologia , Animais , Quimera/genética , Encefalomielite Autoimune Experimental/genética , Epitopos/imunologia , Glicoproteínas/genética , Glicoproteínas/imunologia , Humanos , Imunoglobulinas/genética , Interleucina-5/metabolismo , Camundongos , Camundongos Mutantes , Proteínas da Mielina , Proteína Proteolipídica de Mielina/genética , Proteína Proteolipídica de Mielina/imunologia , Glicoproteína Associada a Mielina/genética , Glicoproteína Associada a Mielina/imunologia , Glicoproteína Mielina-Oligodendrócito , Proteínas do Tecido Nervoso/imunologia , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Peptídeos/imunologia
17.
J Exp Med ; 205(1): 207-18, 2008 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-18195074

RESUMO

The role of Th17 cells in type I diabetes (TID) remains largely unknown. Glutamic acid decarboxylase (GAD) sequence 206-220 (designated GAD2) represents a late-stage epitope, but GAD2-specific T cell receptor transgenic T cells producing interferon gamma (IFNgamma) protect against passive TID. Because IFNgamma is known to inhibit Th17 cells, effective presentation of GAD2 peptide under noninflammatory conditions may protect against TID at advanced disease stages. To test this premise, GAD2 was genetically incorporated into an immunoglobulin (Ig) molecule to magnify tolerance, and the resulting Ig-GAD2 was tested against TID at different stages of the disease. The findings indicated that Ig-GAD2 could not prevent TID at the preinsulitis phase, but delayed TID at the insulitis stage. More importantly, Ig-GAD2 sustained both clearance of pancreatic cell infiltration and beta-cell division and restored normoglycemia when given to hyperglycemic mice at the prediabetic stage. This was dependent on the induction of splenic IFNgamma that inhibited interleukin (IL)-17 production. In fact, neutralization of IFNgamma led to a significant increase in the frequency of Th17 cells, and the treatment became nonprotective. Thus, IFNgamma induced by an adjuvant free antigen, contrary to its usual inflammatory function, restores normoglycemia, most likely by localized bystander suppression of pathogenic IL-17-producing cells.


Assuntos
Antígenos/química , Glicemia/metabolismo , Regulação da Expressão Gênica , Hiperglicemia/genética , Interferon gama/metabolismo , Interleucina-17/antagonistas & inibidores , Animais , Epitopos/química , Hiperglicemia/prevenção & controle , Interleucina-17/metabolismo , Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Biológicos , Fenótipo , Proteínas Recombinantes
18.
J Immunol ; 180(1): 179-87, 2008 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18097018

RESUMO

Currently, transition of T cells from effector to memory is believed to occur as a consequence of exposure to residual suboptimal Ag found in lymphoid tissues at the waning end of the effector phase and microbial clearance. This led to the interpretation that memory arises from slightly activated late effectors producing reduced amounts of IFN-gamma. In this study, we show that CD4 T cells from the early stage of the effector phase in which both the Ag and activation are optimal also transit to memory. Moreover, early effector T cells that have undergone four divisions expressed significant IL-7R, produced IFN-gamma, and yielded rapid and robust memory responses. Cells that divided three times that had marginal IL-7R expression and no IFN-gamma raised base level homeostatic memory, whereas those that have undergone only two divisions and produced IFN-gamma yielded conditioned memory despite low IL-7R expression. Thus, highly activated early effectors generated under short exposure to optimal Ag in vivo develop into memory, and such transition is dependent on a significant production of the cell's signature cytokine, IFN-gamma.


Assuntos
Memória Imunológica , Interferon gama/metabolismo , Linfócitos T/imunologia , Animais , Divisão Celular , Proteínas de Ligação a DNA/genética , Interferon gama/genética , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos , Camundongos Transgênicos , Receptores de Interleucina-7/genética , Receptores de Interleucina-7/metabolismo , Baço/imunologia
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