Study of cytokines and apoptosis-related molecules in systemic lupus erythematosus and allergic asthma

Recent studies have shown the important roles of T helper (Th) and proinflammatory cytokines, and apoptosis and its related molecules in the development of both systemic lupus erythematosus (SLE) and allergic asthma.; The objective of this study was to measure the plasma concentrations of Th1 cytokine IL-12, Th2 cytokine IL-4, and two novel proinflammatory cytokines IL-17 and EL-18 in SLE patients and normal control subjects. We also evaluated the effect of dexamethasone (DEX) on apoptosis and expressions of apoptosis-related molecules, Fas and Bcl-2, of their peripheral blood lymphocytes. In the study of allergic asthma, we compared the plasma concentrations of EL-17 and IL-18, Th2 cytokines IL-10 and IL-13, and ratio of interferon-γ (IFN-γ)- and IL-4-producing Th cells in allergic asthmatics and normal controls. We also investigated the apoptosis of peripheral blood T lymphocytes in allergic asthmatics upon DEX treatment in vitro, and their expressions of Fas and Bcl-2, and gene expressions of several Bcl-2 family members ex vivo.; Plasma cytokines were measured by enzyme-linked immunosorbent assay (ELISA) and intracellular cytokines quantitated by flow cytometry. Apoptosis and expressions of Fas and Bcl-2 were assessed by flow cytometry. Gene expressions of Bax, Bcl-2, Bcl-X_L, p53 and caspase-3 were determined by reverse transcription-polymerase chain reaction (RT-PCR).; In allergic asthma patients with or without steroid therapy, the ratios of IFN-γ-/IL-4-producing Th cells were significantly lower than the normal control subjects, suggesting the existence of Th2 predominance. Plasma levels of IL-10, IL-13, IL-17, IL-18, allergen-specific IgE and ECP were significantly elevated in allergic asthmatics when compared with control subjects, which might be related to the development of allergic inflammation. Several reports have proposed that there may be a mutual antagonism between DEX-induced apoptosis and AICD. In our study, the CD3-stimulated T cells of allergic asthmatics without steroid therapy had a significant elevation in apoptosis treated with DEX in vitro, while a reduced apoptosis was seen in the control subjects.; It is hoped that the above findings can provide better understanding of the key roles of cytokines, apoptosis and its related molecules in the pathogenesis of SLE and allergic asthma. This may ultimately lead to the development of more efficacious strategies for the treatment of these two diseases. (Abstract shortened by UMI.)...