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2.
Arthritis Care Res (Hoboken) ; 76(3): 328-339, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37691306

RESUMO

OBJECTIVE: Systemic juvenile idiopathic arthritis-associated lung disease (SJIA-LD) is a life-threatening disease complication. Key questions remain regarding clinical course and optimal treatment approaches. The objectives of the study were to detail management strategies after SJIA-LD detection, characterize overall disease courses, and measure long-term outcomes. METHODS: This was a prospective cohort study. Clinical data were abstracted from the electronic medical record, including current clinical status and changes since diagnosis. Serum biomarkers were determined and correlated with presence of LD. RESULTS: We enrolled 41 patients with SJIA-LD, 85% with at least one episode of macrophage activation syndrome and 41% with adverse reactions to a biologic. Although 93% of patients were alive at last follow-up (median 2.9 years), 37% progressed to requiring chronic oxygen or other ventilator support, and 65% of patients had abnormal overnight oximetry studies, which changed over time. Eighty-four percent of patients carried the HLA-DRB1*15 haplotype, significantly more than patients without LD. Patients with SJIA-LD also showed markedly elevated serum interleukin-18 (IL-18), variable C-X-C motif chemokine ligand 9 (CXCL9), and significantly elevated matrix metalloproteinase 7. Treatment strategies showed variable use of anti-IL-1/6 biologics and addition of other immunomodulatory treatments and lung-directed therapies. We found a broad range of current clinical status independent of time from diagnosis or continued biologic treatment. Multidomain measures of change showed imaging features were the least likely to improve with time. CONCLUSION: Patients with SJIA-LD had highly varied courses, with lower mortality than previously reported but frequent hypoxia and requirement for respiratory support. Treatment strategies were highly varied, highlighting an urgent need for focused clinical trials.


Assuntos
Artrite Juvenil , Pneumopatias , Síndrome de Ativação Macrofágica , Criança , Humanos , Artrite Juvenil/complicações , Artrite Juvenil/diagnóstico , Artrite Juvenil/tratamento farmacológico , Estudos Prospectivos , Pulmão , Síndrome de Ativação Macrofágica/diagnóstico , Síndrome de Ativação Macrofágica/etiologia , Síndrome de Ativação Macrofágica/terapia , Progressão da Doença
3.
Pediatr Neurol ; 151: 1-4, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38041904

RESUMO

BACKGROUND: Bilateral Rasmussen encephalitis is a rare variant of a debilitating, typically unihemispheric disease with limited treatment options. Few cases with bilateral histopathology have been reported, all with poor seizure control following surgery. Here we report a favorable outcome following hemispherotomy in a four-year-old male with biopsy-confirmed bilateral disease. CASE: The patient presented with right hemispheric focal seizures with behavioral arrest and over a year progressed to left lower extremity clonic seizures, epilepsia partialis continua, and loss of ambulation, with transient response to steroids and tacrolimus. Histopathology confirmed bilateral disease. The patient developed super-refractory status epilepticus and underwent right functional hemispherotomy 4.5 years after initial presentation. In a 2.5-year follow-up period, an Engel 1D outcome classification was observed with substantially improved quality of life. CONCLUSION: Previous reports of bilateral Rasmussen encephalitis describe universally poor outcomes, and hemispherotomy is often considered contraindicated. However, hemispherotomy in a patient with bilateral Rasmussen encephalitis may have a good outcome if seizures are unihemispheric.


Assuntos
Encefalite , Inflamação , Qualidade de Vida , Masculino , Humanos , Pré-Escolar , Encefalite/patologia , Convulsões , Esteroides , Resultado do Tratamento , Imageamento por Ressonância Magnética
4.
Pediatr Dermatol ; 40(5): 789-808, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37316462

RESUMO

Methotrexate (MTX) is a readily accessible drug, first used in 1948 and employed for a wide variety of indications since then. However, despite widespread off-label use, FDA labeling does not include approved indications for the use of MTX for many inflammatory skin diseases in pediatric patients, including morphea, psoriasis, atopic dermatitis, and alopecia areata, among others. Without published treatment guidelines, some clinicians may be hesitant to use MTX off-label, or uncomfortable prescribing MTX in this population. To address this unmet need, an expert consensus committee was convened to develop evidence- and consensus-based guidelines for use of MTX to treat pediatric inflammatory skin disease. Clinicians with experience and expertise in clinical research, drug development, and treating inflammatory skin disease in pediatric patients with MTX were recruited. Five committees were created based on major topic areas: (1) indications and contraindications, (2) dosing, (3) interactions with immunizations and medications, (4) adverse effects (potential for and management of), and (5) monitoring needs. Pertinent questions were generated and addressed by the relevant committee. The entire group participated in a modified Delphi process to establish agreement on recommendations for each question. The committee developed 46 evidence- and consensus-based recommendations, each with >70% agreement among members, across all five topics. These are presented in tables and text, along with a discussion of supporting literature, and level of evidence. These evidence- and consensus-based recommendations will support safe and effective use of MTX for the underserved population of pediatric patients who may benefit from this valuable, time-honored medication.


Assuntos
Dermatite Atópica , Psoríase , Humanos , Criança , Metotrexato , Consenso , Psoríase/tratamento farmacológico , Dermatite Atópica/tratamento farmacológico
5.
Crit Care Clin ; 38(2): 393-412, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35369953

RESUMO

Autoimmune encephalitis is characterized by subacute onset of the altered mental status that can rapidly progress to autonomic instability and refractory seizures requiring intensive care. It is mediated by autoantibodies that bind to synaptic surface proteins and alter their function. In contrast to many autoimmune CNS diseases, there is often little detectable inflammatory damage to the brain making it difficult to diagnose. Early engagement of a multidisciplinary team is essential to obtaining a complete diagnostic workup and instituting definitive therapy as early as possible to optimize outcomes. Diagnosis, treatment, and monitoring for this devastating condition continue to evolve. Pathogenesis, diagnosis and both current and emerging therapies are reviewed.


Assuntos
Encefalite , Doença de Hashimoto , Autoanticorpos , Encéfalo , Cuidados Críticos , Encefalite/diagnóstico , Encefalite/terapia , Doença de Hashimoto/diagnóstico , Doença de Hashimoto/terapia , Humanos
6.
Cells ; 10(12)2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34943793

RESUMO

Infections with pathogenic mycobacteria are controlled by the formation of a unique structure known as a granuloma. The granuloma represents a host-pathogen interface where bacteria are killed and confined by the host response, but also where bacteria persist. Previous work has demonstrated that the T cell repertoire is heterogenous even at the single granuloma level. However, further work using pigeon cytochrome C (PCC) epitope-tagged BCG (PCC-BCG) and PCC-specific 5CC7 RAG-/- TCR transgenic (Tg) mice has demonstrated that a monoclonal T cell population is able to control infection. At the chronic stage of infection, granuloma-infiltrating T cells remain highly activated in wild-type mice, while T cells in the monoclonal T cell mice are anergic. We hypothesized that addition of an acutely activated non-specific T cell to the monoclonal T cell system could recapitulate the wild-type phenotype. Here we report that activated non-specific T cells have access to the granuloma and deliver a set of cytokines and chemokines to the lesions. Strikingly, non-specific T cells rescue BCG-specific T cells from anergy and enhance the function of BCG-specific T cells in the granuloma in the chronic phase of infection when bacterial antigen load is low. In addition, we find that these same non-specific T cells have an inhibitory effect on systemic BCG-specific T cells. Taken together, these data suggest that T cells non-specific for granuloma-inducing agents can alter the function of granuloma-specific T cells and have important roles in mycobacterial immunity and other granulomatous disorders.


Assuntos
Comunicação Celular , Granuloma/imunologia , Granuloma/microbiologia , Mycobacterium/fisiologia , Linfócitos T/imunologia , Animais , Antígenos de Bactérias/imunologia , Conalbumina , Citocromos c/metabolismo , Citocinas/metabolismo , Imunização , Ativação Linfocitária/imunologia , Ativação de Macrófagos , Camundongos Transgênicos , Modelos Biológicos , Mycobacterium bovis/fisiologia , Baço/citologia , Regulação para Cima
7.
Pediatr Dermatol ; 38(2): 413-419, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33438772

RESUMO

BACKGROUND/OBJECTIVES: Clinically amyopathic juvenile dermatomyositis (CAJDM) is an uncommon but important subset of patients with juvenile dermatomyositis, characterized by pathognomonic cutaneous findings without clinically evident muscle weakness. With limited data available and lack of standardized management guidelines for CAJDM, we sought to describe common features, including early indicators that may be associated with progression of muscle disease, and review the course and treatment of these patients. METHODS: A retrospective chart review of patients with CAJDM was conducted at four North American academic centers between the years 2000 and 2015. RESULTS: Twenty-nine patients were included, of whom 21 (72%) were female. After a median follow-up of 4 years (IQR 1.8-5.8 years), 5 of the 29 (17%) patients with CAJDM evolved into classic juvenile dermatomyositis. Median time to develop weakness was 12 months (IQR 8-19 months) after diagnosis. The skin disease of CAJDM patients who did not develop weakness was often found to be recalcitrant with 58% of them requiring multiple systemic therapies to control their cutaneous disease. CONCLUSION: These results highlight the need for long-term monitoring for the development of myositis in CAJDM and for prospective studies on treatment of recalcitrant skin disease.


Assuntos
Dermatomiosite , Doenças Musculares , Miosite , Dermatomiosite/complicações , Dermatomiosite/diagnóstico , Dermatomiosite/tratamento farmacológico , Feminino , Humanos , Masculino , Estudos Prospectivos , Estudos Retrospectivos
8.
Arthritis Rheumatol ; 72(11): 1945-1951, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32524767

RESUMO

OBJECTIVE: To document the need for additional Food and Drug Administration (FDA)-approved medications for the treatment of juvenile idiopathic arthritis (JIA). METHODS: The electronic medical records of JIA patients treated at Cincinnati Children's Hospital Medical Center (CCHMC) and data from JIA patients enrolled in the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry were included in this study. Unmet medication need was defined in 2 ways: (a) the presence of chronically uncontrolled JIA, defined as a physician global assessment of JIA activity ≥3 (on a 0-10 scale, where 0 = inactive) OR ≥3 joints with active arthritis OR a patient global assessment of well-being ≥3 (on a 0-10 scale, where 0 = very well), despite sequential use of ≥2 biologic disease-modifying antirheumatic drugs (bDMARDs); and (b) the use of ≥1 bDMARD not approved for any JIA category. RESULTS: At CCHMC, 829 of 1,599 JIA patients (52%) were treated with ≥1 bDMARD, and 304 (19%) had been exposed to ≥1 unapproved bDMARD. In the CARRA Registry, 4,766 of 7,379 children (65%) had received ≥1 bDMARD, and 1,122 (15%) had been prescribed ≥1 unapproved bDMARD. Of those children treated with ≥2 bDMARDs for whom complete data were available, 52% (255 of 487) at CCHMC and 45% (527 of 1,159) in the CARRA Registry had chronically uncontrolled JIA despite the use of ≥2 bDMARDs. CONCLUSION: Despite the availability of bDMARDs currently approved for JIA, there is persistent need for additional therapies to control JIA signs and symptoms. Since FDA approval is critical to ensure access to bDMARDs, the study and licensing of new medications is critical to address the unmet medication need and to further improve JIA outcomes.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Juvenil/tratamento farmacológico , Necessidades e Demandas de Serviços de Saúde , Criança , Humanos , Sistema de Registros
9.
Pediatr Dermatol ; 37(3): 572-573, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32198786

RESUMO

Lipoatrophic panniculitis (LP) is a rare childhood panniculitis characterized by sclerotic, atrophic plaques on the extremities. We present a case of LP diagnosed during the inflammatory phase that was difficult to distinguish clinically from eosinophilic fasciitis. This report adds to the limited phenotypic spectrum of LP by differentiating the clinical features of disease activity from disease damage and highlighting the importance of biopsy in establishing a diagnosis.


Assuntos
Doenças do Tecido Conjuntivo , Paniculite , Adolescente , Atrofia , Biópsia , Criança , Humanos , Paniculite/diagnóstico
10.
Pediatr Dermatol ; 37(3): 467-475, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32104943

RESUMO

BACKGROUND: Hypergammaglobulinemic purpura of Waldenström (HGPW), a rare cutaneous eruption characterized by the triad of recurrent episodes of lower extremity petechiae, symptoms of stinging and burning, and lower extremity edema, is poorly described in children. Some children have been reported to follow a benign course, while others are eventually diagnosed with fulminant rheumatologic disease. OBJECTIVES: To determine the distinguishing features of HGPW including the spectrum of disease manifestations and clinical outcomes. METHODS: This is a multicenter, retrospective case series of six children with HGPW combined with a literature review of 45 previously published pediatric cases. RESULTS: Most children were eventually diagnosed with systemic disease (63%) or developed autoantibody accumulation suggestive of evolving disease (71%). The most common diagnoses were Sjogren's syndrome and systemic lupus erythematosus. The mean duration between onset of cutaneous eruption and diagnosis of systemic disease was 5.6 years, underscoring that HPGW patients often present with a rash that precedes the development of systemic symptoms. CONCLUSIONS: Diagnosis of HGPW should prompt initial screening for rheumatologic disease with long-term rheumatology follow-up, as the majority of patients present with evolving manifestations of systemic disease.


Assuntos
Lúpus Eritematoso Sistêmico , Púrpura Hiperglobulinêmica , Púrpura , Síndrome de Sjogren , Criança , Humanos , Estudos Retrospectivos
11.
Pediatr Clin North Am ; 64(1): 57-90, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27894452

RESUMO

Immune-mediated diseases of the central nervous system show wide variability both symptomatically and with respect to underlying pathophysiology. Recognizing aberrant immunologic activity as the cause of neurologic dysfunction requires establishing as precise a neuroanatomic and functional phenotype as possible, and a diagnostic and therapeutic strategy that stabilizes the patient, excludes broad categories of disease via rapidly available diagnostic assays, and maintains a broad differential diagnosis that includes immune-mediated conditions. This process is aided by recognizing the appropriate clinical circumstances under which immune-mediated disease should be suspected, and how to differentiate these conditions from other causes of similar neurologic dysfunction.


Assuntos
Doenças Autoimunes do Sistema Nervoso/diagnóstico , Doenças Autoimunes do Sistema Nervoso/imunologia , Doenças Raras/diagnóstico , Doenças Raras/imunologia , Criança , Diagnóstico Tardio , Diagnóstico Diferencial , Humanos , Fenótipo
12.
Pediatr Dermatol ; 34(1): 50-57, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27813167

RESUMO

BACKGROUND: Pediatric patients can present with skin manifestations of dermatomyositis without overt weakness (clinically amyopathic juvenile dermatomyositis [JDM]), but it is unclear how often this happens and how often they have subclinical muscle inflammation. OBJECTIVE: Our goal was to determine the frequency of clinically amyopathic JDM and the frequency with which a thorough evaluation uncovers subclinical myositis at a single institution. METHODS: A retrospective review was performed of 46 patients diagnosed with JDM at Children's Hospital of Wisconsin. RESULTS: Of 46 patients presenting with skin findings consistent with dermatomyositis, 10 patients (21.7%) did not have evidence of muscle involvement on history or exam, and these tended to be the younger patients. Of these 10, only 2 (4% of all the JDM patients) were truly amyopathic upon further evaluation (all five muscle enzymes [aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, creatine kinase and aldolase], magnetic resonance imaging [MRI], muscle biopsy). In our series, muscle biopsy was not helpful in identifying subclinical myositis. In contrast, MRI did uncover subclinical muscle disease. CONCLUSION: These data suggest that truly amyopathic JDM is rare and that a thorough workup that includes all five muscle enzymes and MRI may uncover occult myositis.


Assuntos
Dermatomiosite/diagnóstico , Músculo Esquelético/patologia , Adolescente , Biópsia , Criança , Pré-Escolar , Dermatomiosite/epidemiologia , Feminino , Hospitais Pediátricos , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Wisconsin
13.
Pediatrics ; 137(6)2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27245834

RESUMO

Bullous eruptions in patients with underlying systemic lupus erythematosus (LE) can mimic toxic-epidermal necrolysis (TEN), a rapidly progressive mucocutaneous reaction usually associated with medication use. Differentiating between classic drug-induced TEN and TEN-like cutaneous LE is important but difficult. We report a series of 3 patients with pediatric systemic LE who were admitted with severe worsening of skin disease resembling TEN. However, the initial photo-distribution of the eruption, subacute progression, limited mucosal involvement, mild systemic symptoms, supportive biopsy and laboratory results, and lack of culprit drugs was more suggestive of a TEN-like cutaneous LE. These patients recovered with various systemic immunosuppressive medications including methylprednisolone, intravenous immunoglobulin, and plasmapheresis. Our cases are rare and demonstrate key clinical and histologic features of TEN-like cutaneous LE in young patients and the importance of differentiating this entity from drug-induced TEN.


Assuntos
Lúpus Eritematoso Cutâneo/diagnóstico , Lúpus Eritematoso Sistêmico/complicações , Pele/patologia , Síndrome de Stevens-Johnson/diagnóstico , Adolescente , Biópsia , Criança , Diagnóstico Diferencial , Feminino , Humanos , Lúpus Eritematoso Cutâneo/patologia , Masculino , Síndrome de Stevens-Johnson/etiologia
14.
J Immunol ; 191(11): 5460-76, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24163409

RESUMO

To study regulatory T (Treg) cell control of chronic autoimmunity in a lymphoreplete host, we created and characterized a new model of autoimmune lung inflammation that targets the medium and small airways. We generated transgenic mice that express a chimeric membrane protein consisting of hen egg lysozyme and a hemoglobin epitope tag under the control of the Clara cell secretory protein promoter, which largely limited transgene expression to the respiratory bronchioles. When Clara cell secretory protein-membrane hen egg lysozyme/hemoglobin transgenic mice were crossed to N3.L2 TCR transgenic mice that recognize the hemoglobin epitope, the bigenic progeny developed dense, pseudo-follicular lymphocytic peribronchiolar infiltrates that resembled the histological pattern of follicular bronchiolitis. Aggregates of activated IFN-γ- and IL-17A-secreting CD4(+) T cells as well as B cells surrounded the airways. Lung pathology was similar in Ifng(-/-) and Il17a(-/-) mice, indicating that either cytokine is sufficient to establish chronic disease. A large number of Ag-specific Treg cells accumulated in the lesions, and Treg cell depletion in the affected mice led to an interstitial spread of the disease that ultimately proved fatal. Thus, Treg cells act to restrain autoimmune responses, resulting in an organized and controlled chronic pathological process rather than a progressive disease.


Assuntos
Linfócitos B/imunologia , Bronquíolos/metabolismo , Bronquiolite/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Animais , Movimento Celular , Células Cultivadas , Doença Crônica , Progressão da Doença , Hemoglobinas/genética , Humanos , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Muramidase/genética , Especificidade de Órgãos/genética , Regiões Promotoras Genéticas/genética , Receptores de Antígenos de Linfócitos T/genética , Proteínas Recombinantes de Fusão/genética , Uteroglobina/genética
15.
Pediatr Dermatol ; 28(4): 357-67, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21793879

RESUMO

Juvenile dermatomyositis (JDM) is an autoimmune disease of the skin and muscle that affects children. The etiology is poorly understood, but genetic susceptibility, environmental triggers, and abnormal immune responses are each thought to play a part. T cells have traditionally been implicated in the immunopathogenesis of JDM, but dendritic cells, B cells, and microchimerism are increasingly associated. Additionally, myositis-specific autoantibodies (MSA) can be present in the sera of affected patients and may correlate with distinct clinical phenotypes. Given the role of humoral immunity and MSA, there has been recent interest in the use of rituximab to treat JDM. Early results are mixed, but it is hoped that a prospective clinical trial will shed light on the issue in the near future.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Autoanticorpos/imunologia , Dermatomiosite/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Aminoacil-tRNA Sintetases/imunologia , Animais , Anticorpos Monoclonais Murinos/efeitos adversos , Autoanticorpos/sangue , Autoanticorpos/genética , Linfócitos B/imunologia , Criança , Quimerismo , Ensaios Clínicos como Assunto , Células Dendríticas/imunologia , Dermatomiosite/genética , Dermatomiosite/imunologia , Feminino , Predisposição Genética para Doença , Humanos , Fatores Imunológicos/efeitos adversos , Masculino , Camundongos , Rituximab , Partícula de Reconhecimento de Sinal/imunologia , Linfócitos T/imunologia , Fatores de Transcrição/imunologia
16.
Infect Immun ; 75(3): 1154-66, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17178783

RESUMO

The effect of secondary infections on CD4 T-cell-regulated chronic granulomatous inflammation is not well understood. Here, we have investigated the effect of an acute viral infection on the cellular composition and bacterial protection in Mycobacterium bovis strain bacille Calmette-Guérin (BCG)-induced granulomas using an immunocompetent and a partially immunodeficient murine model. Acute lymphocytic choriomeningitis virus (LCMV) coinfection of C57BL/6 mice led to substantial accumulation of gamma interferon (IFN-gamma)-producing LCMV-specific T cells in liver granulomas and increased local IFN-gamma. Despite traffic of activated T cells that resulted in a CD8 T-cell-dominated granuloma, the BCG liver organ load was unaltered from control levels. In OT-1 T-cell-receptor (TCR) transgenic mice, ovalbumin (OVA) immunization or LCMV coinfection of BCG-infected mice induced CD8 T-cell-dominated granulomas containing large numbers of non-BCG-specific activated T cells. The higher baseline BCG organ load in this CD8 TCR transgenic animal allowed us to demonstrate that OVA immunization and LCMV coinfection increased anti-BCG protection. The bacterial load remained substantially higher than in mice with a more complete TCR repertoire. Overall, the present study suggests that peripherally activated CD8 T cells can be recruited to chronic inflammatory sites, but their contribution to protective immunity is limited to conditions of underlying immunodeficiency.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Movimento Celular , Granuloma/imunologia , Granuloma/prevenção & controle , Síndromes de Imunodeficiência/imunologia , Ativação Linfocitária , Mycobacterium bovis/imunologia , Animais , Linfócitos T CD8-Positivos/citologia , Movimento Celular/genética , Movimento Celular/imunologia , Granuloma/genética , Granuloma/virologia , Síndromes de Imunodeficiência/patologia , Síndromes de Imunodeficiência/virologia , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
17.
J Immunol ; 177(12): 8456-65, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17142743

RESUMO

CD4(+) T cells are central in mediating granuloma formation and limiting growth and dissemination of mycobacterial infections. To determine whether T cells responding to influenza infection can interact with T cells responding to Mycobacterium bovis bacille Calmette-Guérin (BCG) infection and disrupt granuloma formation, we infected mice containing two monoclonal T cell populations specific for the model Ags pigeon cytochrome c (PCC) and hen egg lysozyme (HEL). These mice were chronically infected with PCC epitope-tagged BCG (PCC-BCG) and acutely infected with HEL epitope-tagged influenza virus (HEL-flu). In these mice, PCC-BCG infection is much more abundant in the liver than the lung, whereas HEL-flu infection is localized to the lung. We observe that both T cells have access to both inflammatory sites, but that PCC-specific T cells dominate the PCC-BCG inflammatory site in the liver, whereas HEL-specific T cells dominate the HEL-flu inflammatory site in the lung. Influenza infection, in the absence of an influenza-specific T cell response, is able to increase the activation state and IFN-gamma secretion of PCC-BCG-specific T cells in the granuloma. Activation of HEL-specific T cells allows them to secrete IFN-gamma and contribute to protection in the granuloma. Ultimately, infection with influenza has little effect on bacterial load, and bacteria do not disseminate. In summary, these data illustrate complex interactions between T cell responses to infectious agents that can affect effector responses to pathogens.


Assuntos
Comunicação Celular/imunologia , Influenza Humana/imunologia , Linfócitos T/fisiologia , Tuberculose/imunologia , Animais , Antígenos/imunologia , Galinhas , Células Clonais , Columbidae , Citocromos c/imunologia , Granuloma/etiologia , Granuloma/imunologia , Humanos , Imunidade , Camundongos , Camundongos Knockout , Muramidase/imunologia , Mycobacterium bovis , Linfócitos T/imunologia , Tuberculose/patologia
18.
J Immunol ; 177(11): 7750-60, 2006 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17114446

RESUMO

Neuroinflammation often starts with the invasion of T lymphocytes into the CNS leading to recruitment of macrophages and amplification of inflammation. In this study, we show that dendritic cells (DCs) facilitate T-T cell help in the CNS and contribute to the amplification of local neuroinflammation. We adoptively transferred defined amounts of naive TCR-transgenic (TCR) recombination-activating gene-1-deficient T cells into another TCR-transgenic mouse strain expressing different Ag specificity. Following adoptive transfers, we coinjected DCs that presented one or multiple Ags into the brain and followed the activation of T cells with defined specificities simultaneously. Injection of DCs presenting both Ags simultaneously led to significantly higher infiltration of T cells into the brain compared with injection of a mixture of DCs pulsed with two Ags separately. DCs mediated either cooperative or competitive interactions between T cell populations with different specificities depending upon their MHC-restricting element usage. These results suggest that DC-mediated cooperation between brain-infiltrating T cells of different Ag specificities in the CNS plays an important role in regulation of neuroinflammation. This work also implies that blocking Ag-specific responses may block not only the targeted specificities, but may also effectively block their cooperative assistance to other T cells. Therefore, these data justify more attention to Ag-specific therapeutic approaches for neuroinflammation.


Assuntos
Apresentação de Antígeno/imunologia , Encéfalo/imunologia , Comunicação Celular/imunologia , Células Dendríticas/imunologia , Linfócitos T/imunologia , Transferência Adotiva , Animais , Encéfalo/patologia , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe II/imunologia , Imuno-Histoquímica , Inflamação/imunologia , Inflamação/patologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Transgênicos , RNA Interferente Pequeno , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Clin Immunol ; 113(2): 130-6, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15451467

RESUMO

Chronic infection with mycobacteria is controlled by the formation of granulomas. The failure of granuloma maintenance results in reactivation of disease. Macrophages are the dominant cell type in granulomas, but CD4+ T cells are the master organizers of granuloma structure and function. Recent work points to an unrecognized role for nonspecific T cells in maintaining granuloma function in the chronic phase of infection. In addition, it has become clear that mycobacteria and host T cells collaborate in formation of granulomas. Further understanding of how nonspecific T cells contribute to granuloma formation, as well as how bacteria and T cells maintain a harmonious relationship over the life of the host, will facilitate the development of new strategies to treat mycobacterial disease.


Assuntos
Granuloma/imunologia , Granuloma/parasitologia , Interações Hospedeiro-Parasita/imunologia , Infecções por Mycobacterium/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Doença Crônica , Citocinas/imunologia , Humanos , Macrófagos/imunologia , Macrófagos/parasitologia , Mycobacterium/imunologia , Subpopulações de Linfócitos T/parasitologia , Linfócitos T/imunologia , Linfócitos T/parasitologia
20.
Immunol Lett ; 92(1-2): 135-42, 2004 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-15081537

RESUMO

Granulomatous inflammation is a form of delayed type hypersensitivity reaction that is involved in protection against chronic infections. Granulomatous inflammation can also occur without any clear inciting stimulus such as in sarcoidosis. An in depth knowledge of granuloma formation is essential to our understanding of protection against chronic infection as well as the dysregulation which occurs in granulomatous diseases of unknown origin. Granuloma formation is a complex and dynamic process involving the recruitment and coordination of diverse cell types. This review is focused on the important roles that T cells play in initiating and building the granuloma as well as in mediating effector functions and eventually resolving granulomatous inflammation. CD4(+) T cells emerge as the central mediators of this process, with T cells from other subsets also participating in the later phases of granuloma formation.


Assuntos
Granuloma/fisiopatologia , Linfócitos T/patologia , Linfócitos T/fisiologia , Animais , Divisão Celular/imunologia , Divisão Celular/fisiologia , Movimento Celular/imunologia , Movimento Celular/fisiologia , Quimiocinas/fisiologia , Granuloma/etiologia , Granuloma/imunologia , Humanos , Receptores de Quimiocinas/fisiologia , Linfócitos T/imunologia
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