[Expression of CD 86 on monocyte and B cell surface, the level of T(H)-derived cytokine and their correlation in children with asthma].

Objective: To explore the role of T lymphocytes activation co-stimulation pathway and T lymphocyte subset activation in asthma pathogenesis.

Methods: The blood samples were taken from 35 asthma children (including 22 male and 13 female, age 11 months-9 years) and 31 normal children (including 19 male and 12 female, age 8 months-12 years). Direct immunofluorescence flow cytometry was used to detect the CD86 mean fluorescence intensity (MFI) on CD(14)(+) cell, CD(19)(+) cell percentage and CD19 and CD86 double positive cell percentage in PBMC activated by LPS. ELISA was used to detect the levels of IL-4, IL-13, IFN-gamma in culture supernatants of PBMC stimulated with PHA and plasma total IgE level.

Results: (1) The CD86 MFI on CD(14)(+) cell in asthma group was elevated significantly (31.8 +/- 9.2 vs 23.5 +/- 6.4, P < 0.01). (2) CD(19)(+) cell percentage and CD19 and CD86 double positive cell percentage in PBMC stimulated with LPS in asthma group were increased significantly (13.5 +/- 4.0 and 4.6 +/- 2.0 vs. 8.2 +/- 3.0 and 2.3 +/- 1.4, respectively, P < 0.01). The plasma total IgE level [186.6 (64.3 - 723.6)] was higher than that of control's [41.95 (0.9 - 115.2)]. (3) The levels of IL-4 and IL-13 in supernatants stimulated with PHA increased significantly [34.2 (2.8 - 70.0) and 1 239.0 (378.3 - 2 929.0) vs. 9.7 (2.0 - 46.2) and 683.2 (128.8 - 1 560.8) respectively, P < 0.01, P < 0.05]; and the level of IFN-gamma decreased significantly [12.16 (1.6 - 44.8) vs. 26.7 (2.1 - 99.5) P < 0.05]. (4) In asthma group there was a significantly positive correlation of CD86 MFI on CD(14)(+) cell with CD19 and CD86 double positive cell percentage (r = 0.644), there was a significantly positive correlation of CD(19)(+)CD(86)(+)cells percentage with plasma total IgE (r = 0.537); there was a significantly positive correlation of CD(19)(+)cells percentage with the levels of IL-4 and IL-13 (r = 0.607, 0.540 respectively); a significantly positive correlation of CD(19)(+)CD(86)(+) percentage cells with the levels of IL-4 and IL-13 was found (r = 0.617, 0.678, respectively).

Conclusions: (1) The expression of CD86 on APC cells increased in children with acute asthma. (2) The response to mitogens of B lymphocyte and T(H2) but not T(H1) lymphocyte were increased significantly. The results suggest that CD86 and imbalance of T(H) subset may play an important role in asthma pathogenesis.