RESUMO
OBJECTIVE: To explore the immunological mechanism of exfoliative tongue fur in children with asthma. METHODS: Thirty-nine children with asthma, twenty-eight children with repetitive respiratory tract infection (non-asthma) and eleven healthy children were divided into five groups, which were asthma with exfoliative fur or with non-exfoliative fur groups, non-asthma with exfoliative fur or with non-exfoliative fur groups and normal control group. The concentrations of keratin 13 and bcl-2 in cells exfoliated from tongue fur were detected by immunohistochemical method. The expression levels of blood cell chemokine receptor-3 (CCR-3) and CD4(+) were examined by flow cytometry, and the levels of serum cortisol and IgE were detected by radioimmunoassay. RESULTS: The levels of blood CD4(+) and CCR-3 of children with asthma and exfoliative fur were higher than those in the asthma with non-exfoliative fur group and the normal control group (P<0.05). The serum level of cortisol in the groups of asthma with exfoliative fur and non-asthma with exfoliative fur were lower than that in the other groups (P<0.05). The serum levels of IgE in asthma with exfoliative fur or with non-exfoliative fur groups were higher than that in the other groups (P<0.05). Concentrations of keratin 13 in the cells exfoliated from tongue fur in the groups of asthma or non-asthma with exfoliative fur were lower than that of the other groups (P<0.05). There was no significant difference of expression level of bcl-2 in the cells exfoliated from tongue fur among these five groups. CONCLUSION: There is a reasonably close relationship between the formation of exfoliative tongue fur and the immune system such as low level of serum cortisol and high levels of blood CD4(+) and CCR-3, which may all promote the formation of exfoliative fur. The disability of keratinization and apoptosis of epithelial cells of tongue may also be one cause for its formation.