RESUMO
BACKGROUND: Overexpression of the transcriptional regulatory factor activator protein 1 might contribute to T-cell glucocorticoid (GC) refractoriness in GC-resistant asthma. OBJECTIVE: We sought to address the hypothesis that clinically GC-resistant asthma is accompanied by failure of systemic GCs to inhibit phosphorylation of c-jun and c-jun N-terminal kinase (JNK) in bronchial mucosal cells. METHODS: We performed enumeration of total (CD45+) leukocytes and cells expressing c-fos and total and phosphorylated c-jun and JNK in bronchial biopsy sections from 9 GC-sensitive and 17 GC-resistant asthmatic patients taken before and after oral prednisolone (40 mg/1.72 m(2) body surface area daily for 14 days) using specific antibodies, immunohistochemistry, and image analysis. RESULTS: At baseline, mean total (CD45+) mucosal leukocytes, total cells expressing phosphorylated c-jun and JNK, and mean percentages of cells in which these molecules were phosphorylated were similar in both groups, whereas mean total numbers of c-fos-immunoreactive cells were increased in the GC-resistant asthmatic subjects (P = .04). After prednisolone, the mean total cells expressing phosphorylated c-jun and JNK and the mean percentages of cells in which these molecules were phosphorylated were significantly reduced in the GC-sensitive (P < or = .02) but not the GC-resistant asthmatic subjects. Mean total CD45+ leukocytes and c-fos-immunoreactive cells were not significantly altered in either group. CONCLUSION: Clinical GC responsiveness in asthma is accompanied by reduced phosphorylation of bronchial mucosal c-jun and JNK, a phenomenon not seen in resistant patients. CLINICAL IMPLICATIONS: Dysregulation of activator protein 1 activation leading to clinical GC resistance might reflect identifiable environmental influences and is a target for future therapy.
Assuntos
Asma/metabolismo , Resistência a Medicamentos , Glucocorticoides/uso terapêutico , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Prednisolona/uso terapêutico , Fator de Transcrição AP-1/metabolismo , Asma/tratamento farmacológico , Asma/imunologia , Brônquios/efeitos dos fármacos , Brônquios/metabolismo , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Antígenos Comuns de Leucócito/imunologia , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Leucócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/metabolismo , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismoRESUMO
BACKGROUND: Cysteinyl leukotrienes play a disease-regulating role in rhinosinusitis and asthma, particularly aspirin-sensitive disease. They act through 2 G-protein coupled receptors termed cysteinyl leukotriene type 1 receptor (cysLT 1 ) and cysteinyl leukotriene type 2 receptor (cysLT 2 ). We previously compared expression of cysLT 1 on mucosal leukocytes in patients with aspirin-sensitive and aspirin-tolerant rhinosinusitis. OBJECTIVE: To compare expression of cysLT 1 and cysLT 2 on leukocytes, mucus glands, and epithelium in 32 patients with chronic polypoid rhinosinusitis (21 aspirin-sensitive, 11 aspirin-tolerant) and 9 normal controls. METHODS: Total numbers of CD45 + leukocytes, percentages of these cells expressing cysLT 1 or cysLT 2 , and percentages of the total epithelial and glandular areas expressing cysLT 1 or cysLT 2 were measured in sections of nasal biopsies by using immunohistochemistry and image analysis. RESULTS: The percentages of mucosal CD45 + leukocytes expressing cysLT 1 were significantly ( P < .0001) elevated in the aspirin-sensitive but not the aspirin-tolerant patients compared with the controls. In contrast, the percentages of leukocytes expressing cysLT 2 did not differ significantly in the 3 groups. On epithelial and glandular cells, expression of cysLT 2 significantly exceeded that of cysLT 1 in both the patients with rhinosinusitis and the controls ( P < or = .004), although there was no significant difference in the expression of either receptor in the patients with rhinosinusitis (aspirin-sensitive or aspirin-tolerant) and the controls. CONCLUSION: Although cysLT 1 expression predominates on inflammatory leukocytes in patients with aspirin-sensitive rhinosinusitis, the effects of cysteinyl leukotrienes on glands and epithelium may be mediated predominantly through cysLT 2. This has potentially important therapeutic implications.
Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Aspirina/efeitos adversos , Proteínas de Membrana/metabolismo , Receptores de Leucotrienos/metabolismo , Rinite/induzido quimicamente , Rinite/metabolismo , Sinusite/induzido quimicamente , Sinusite/metabolismo , Adulto , Idoso , Doença Crônica , Células Epiteliais/metabolismo , Feminino , Humanos , Leucócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/metabolismo , Mucosa Nasal/patologia , Fenótipo , Rinite/genética , Rinite/patologia , Sinusite/genética , Sinusite/patologiaRESUMO
Thymic stromal lymphopoietin (TSLP) is said to increase expression of chemokines attracting Th2 T cells. We hypothesized that asthma is characterized by elevated bronchial mucosal expression of TSLP and Th2-attracting, but not Th1-attracting, chemokines as compared with controls, with selective accumulation of cells bearing receptors for these chemokines. We used in situ hybridization and immunohistochemistry to examine the expression and cellular provenance of TSLP, Th2-attracting (thymus and activation-regulated chemokine (TARC)/CCL17, macrophage-derived chemokine (MDC)/CCL22, I-309/CCL1) and Th1-attracting (IFN-gamma-inducible protein 10 (IP-10)/CXCL10, IFN-inducible T cell alpha-chemoattractant (I-TAC)/CXCL11) chemokines and expression of their receptors CCR4, CCR8, and CXCR3 in bronchial biopsies from 20 asthmatics and 15 normal controls. The numbers of cells within the bronchial epithelium and submucosa expressing mRNA for TSLP, TARC/CCL17, MDC/CCL22, and IP-10/CXCL10, but not I-TAC/CXCL11 and I-309/CCL1, were significantly increased in asthmatics as compared with controls (p = 0.018). TSLP and TARC/CCL17 expression correlated with airway obstruction. Although the total numbers of cells expressing CCR4, CCR8, and CXCR3 did not significantly differ in the asthmatics and controls, there was evidence of selective infiltration of CD4(+)/CCR4(+) T cells in the asthmatic biopsies which correlated with TARC and MDC expression and airway obstruction. Epithelial cells, endothelial cells, neutrophils, macrophages, and mast cells were significant sources of TSLP and chemokines. Our data implicate TSLP, TARC/CCL17, MDC/CCL22, and IP-10/CXCL10 in asthma pathogenesis. These may act partly through selective development and retention, or recruitment of Th2 cells bearing their receptors.
Assuntos
Asma/imunologia , Quimiocinas CC/biossíntese , Citocinas/biossíntese , Células Th2/imunologia , Regulação para Cima/imunologia , Adulto , Idoso , Asma/patologia , Asma/fisiopatologia , Movimento Celular/imunologia , Quimiocina CCL1 , Quimiocina CCL17 , Quimiocina CCL22 , Quimiocina CXCL10 , Quimiocina CXCL11 , Quimiocinas CC/genética , Quimiocinas CXC/biossíntese , Quimiocinas CXC/genética , Citocinas/genética , Humanos , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , Receptores de Quimiocinas/biossíntese , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Mucosa Respiratória/patologia , Índice de Gravidade de Doença , Células Estromais/imunologia , Células Estromais/metabolismo , Células Th1/imunologia , Células Th1/metabolismo , Células Th2/metabolismo , Timo/imunologia , Timo/metabolismo , Linfopoietina do Estroma do TimoRESUMO
BACKGROUND: Prostaglandin (PG) E 2 binds to 4 G-protein-coupled receptors designated EP 1 through EP 4 . Although PGE 2 plays an immunomodulatory role in asthma, there is little information on the expression of PGE 2 receptors in this disease. OBJECTIVE: We hypothesized that profiles of E-prostanoid (EP) receptor expression are altered on asthmatic bronchial inflammatory cells in vivo and further altered by allergen challenge in vivo and proinflammatory mediators in vitro. METHODS: The numbers and phenotypes of EP 1-4 immunoreactive induced sputum cells from atopic asthmatics (n = 13; before and 24 hours after allergen inhalational challenge) and normal controls (n = 9; 3 after saline challenge) and EP 1-4 expression on purified blood eosinophils from both groups (n = 4 for each) before and after stimulation with LPS and/or IL-5 in vitro were measured by using single and double immunocytochemistry. RESULTS: Subsets of sputum cells of all phenotypes expressed all 4 EP receptors in both patients with asthma and controls. There were significantly greater numbers of macrophages expressing all 4 EP receptors and increased percentages of macrophages expressing EP 2 and EP 4 in patients with asthma compared with controls. Allergen bronchial challenge of patients with asthma was associated with a selective influx of eosinophils, but the percentages of these and other leukocytes expressing all 4 EP receptors were unchanged. Compared with sputum, only small percentages of peripheral blood eosinophils expressed each receptor, but this was increased by culture with exogenous IL-5 or LPS. CONCLUSION: E-prostanoid receptor expression is increased on airway macrophages of patients with asthma at baseline and may be altered on eosinophils after allergen challenge in vivo in response to inflammatory stimuli.