Role of Activator Protein-1 in the Transcription of InterIeukin-5 Gene Regulated by Protein Kinase C Signal in Asthmatic Human T Lymphocytes

摘要

In order to explore the role of activator protein-1 (AP-1) in the transcription of interleu-kin-5 (IL-5) gene regulated by protein kinase C (PKC) signal in peripheral blood T lymphocytes from asthmatic patient, T lymphocytes were isolated and purified from peripheral blood of each asthmatic patient. The T lymphocytes were randomly divided into 4 groups: group A (blank control), group B (treated with PKC agonist phorbol 12-myristate 13-acetate (PMA)), Group C (treated with PMA and AP-1 cis-element decoy oligodeoxynucleotides (decoy ODNs)), and group D (treated with PMA and AP-1 mutant decoy ODNs). The ODNs were transfected into the T cells of group C and D by cation liposome respectively. Reverse transcription-polymerase chain reaction (RT-PCR) was employed to assess IL-5 mRNA expression, and electrophoretic mobility shift assays (EMSA) for the activation of AP-1. The results showed that the activation of AP-1 (88 003. 58 +- 1 626. 57) and the expression of IL-5 mRNA (0. 8300 +- 0. 0294) in T lymphocytes stimulated with PMA were significantly higher than these in blank control (20 888. 47 +- 1103. 56 and 0. 3050 +- 0. 0208, respectively, P < 0. 01), while the indexes (23 219. 83 +- 1 024. 86 and 0. 3425 +- 0. 0171 respectively) of T lymphocytes stimulated with PMA and AP-1 decoy ODNs were significantly inhibited, as compared with group B (P < 0. 01). The indexes (87 107. 41 ± 1 342. 92 and 0. 8225 ± 0. 0222, respectively) in T lymphocytes stimulated with PMA and AP-1 mutant decoy ODNs did not exhibit significant changes, as compared with group B (P > 0. 05). The significant positive correlation was found between the activation of AP-1 and the expression of IL-5 mRNA (P < 0. 01). It was concluded that AP-1 might participate in the signal transduction of PKC-triggered transcription of IL-5 gene in asthmatic T lymphocytes. This suggests the activation of PKC/AP-1 signal transduction cascade of T lymphocytes may play an important role in the pathogenesis of asthma.