Differences in allergen - specific Th and Tc cel responses between pre - and post - immunotherapy asthmatics / 천식및알레르기

ABSTRACT

BACKGROUND: Allergen-specific immunotherapy ( IT ) can be an important adjunctive therapy in the treatment of allergic disorders. Although a number of studies have shown that cytokine production by T cells may be modified by IT, IT-induced chsnges at the single cell level in allergen -specific Th ( T helper ) and Tc ( cytotoxic T ) responses have not been reported. Objective: The objectives of the present study were ( 1 ) to demonstrate differences in the house dust mite(HDM)-induced cytokine production patterns of Th and Tc cells between untreated and treated HDM allergic patients and ( 2 ) to determine whether there are differences between child and adult patients in Th and Tc cell responses to HDM. METHOD: This study included twenty Dermatophagoides farinae (Df)-sensitive asthmatics ( ten children and ten adults ), of which five children and five adults received immunotherapy to Df over a 1.5- to 3-year period. Peripheral blood mononuclear cells ( PBMC ) were isolated from peripheral blood of each patient and cultured in the presence of IL-2 ( 10ng/ml ) and Df extract (100ug/ml) for 6 days. After harvesting cultured cells, Th and Tc cell frequencies were determined by a multiparameter cytokine flow cytometric assay that allows simultaneous determination of intracellular IFN-r and IL-4 in CD4+ or CD8+ cells. RESULTS: Predominant Th2 responses to Df were observed in all untreated child patients, three untreated adult patients, and two treated adult patients. On the other hand, predominant Thl responses to Df were observed in all treated child patients, two of untreated adult patients, and three of treated adult patients. Predominant Tcl responses to Df were observed in all groups of patients. However, Tcl responses were more prominent in adults than in children and in treated adult patients than in untreated adult patients. In children, there were no differences in predominant Tcl responses except in one treated child, in whom more prominent Tcl response was observed.