RESUMO
BACKGROUND: The role of neurotrophins in allergic rhinitis (AR) has been well studied, but it has not been evaluated in idiopathic rhinitis (IR). OBJECTIVE: We aimed to evaluate the nasal ß-nerve growth factor (ß-NGF) expressions of mast cells in patients with AR and IR. METHODS: Seventeen patients with house dust mites-induced persistent moderate/severe allergic rhinitis (mean age: 29.7 ± 11.96), 14 patients with idiopathic rhinitis (mean age, 29.3 ± 10.62), and 16 healthy controls (29.9 ± 11.57) were included in the study. Nasal biopsy specimens were taken from the posterior part of the inferior turbinate from all of the study subjects. Nasal ß-nerve growth factor and its receptors, pan-neurotrophin receptor p75, and tyrosine kinase A (trkA) were assessed with an immunofluorescence assay. Mast cells were determined by both an immunofluorescence assay and immunohistochemistry as tryptase-positive cells. RESULTS: The ß-NGF, trkA, and p75 receptor counts were significantly higher in AR and IR patients than in the control group (P < .001, for each), but they were not different between AR and IR patients. Similarly, the ratio of ß-NGF+ mast cells/total mast cells and the ratio of ß-NGF+ mast cells/total ß-NGF+ cells in AR and IR patients was found to be elevated when compared with the control group (P < .001, P < .001, P < .001, and P = .046, respectively); furthermore, the 2 ratios were not statistically different between the 2 patient groups. CONCLUSION: The increase in ß-NGF-expressing mast cells does not differ between idiopathic and allergic rhinitis. Therefore, we propose that mast cells do play a role in the pathogenesis of IR as important as in that of AR.
Assuntos
Mastócitos/metabolismo , Fator de Crescimento Neural/genética , Rinite Alérgica Perene/imunologia , Rinite Vasomotora/imunologia , Adolescente , Adulto , Estudos de Casos e Controles , Contagem de Células , Feminino , Expressão Gênica , Humanos , Masculino , Mastócitos/citologia , Mastócitos/imunologia , Mucosa Nasal/imunologia , Mucosa Nasal/fisiopatologia , Fator de Crescimento Neural/imunologia , Receptor de Fator de Crescimento Neural/genética , Receptor de Fator de Crescimento Neural/imunologia , Receptor trkA/genética , Receptor trkA/imunologia , Rinite Alérgica Perene/genética , Rinite Alérgica Perene/fisiopatologia , Rinite Vasomotora/genética , Rinite Vasomotora/fisiopatologia , TurquiaRESUMO
We sought a genotype-phenotype association: between single-nucleotide polymorphisms (SNPs) in olfactory receptor (OR) genes from the two largest OR gene clusters and odor-triggered nonallergic vasomotor rhinitis (nVMR). In the initial pedigree screen, using transmission disequilibrium test (TDT) analysis, six SNPs showed "significant" p-values between 0.0449 and 0.0043. In a second case-control population, the previously identified six SNPs did not re-emerge, whereas four new SNPs showed p-values between 0.0490 and 0.0001. Combining both studies, none of the SNPs in the TDT analysis survived the Bonferroni correction. In the population study, one SNP showed an empirical p-value of 0.0066 by shuffling cases and controls with 10(5) replicates; however, the p-value for this SNP was 0.83 in the pedigree study. This study emphasizes that underpowered studies having p-values between < 0.05 and 0.0001 should be regarded as inconclusive and require further replication before concluding the study is "informative." However, we believe that our hypothesis that an association between OR genotypes and the nVMR phenotype remains feasible. Future studies using either a genomewide association study of all OR gene-pseudogene regions throughout the genome--at the current recommended density of 2.5 to 5 kb per tag SNP--or studies incorporating microarray analyses of the entire "OR genome" in well-characterized nVMR patients are required.
