Résumé
The study was aimed to explore the effects of T-bet (T-box expressed in T cell), GATA-3(GATA binding protein 3) and relevant signal transduction pathways on the immune-related pathogenesis of chronic aplastic anemia (CAA), and to investigate the immunological regulation mechanism in the treatment of CAA by using cyclosporine A (CsA) at the level of Th cell imbalance, transcriptional factors, and relevant signal pathways. The real-time fluorescent quantitative polymerase chain reaction (real-time FQ-PCR) was used to determine the mRNA expression of T-bet, GATA-3, signal transducers and activators of transcription 4 (STAT4) and signal transducers and activators of transcription 6 (STAT6) in peripheral blood mononuclear cell (PBMNC) of CAA patients before and after treatment with CsA; the flow cytometry (FCM) and enzyme linked immunosorbent assay (ELISA) were used to determine the Th1/Th2 proportion in peripheral blood, and levels of IFN-γ, IL-12 and IL-4 in PBMNC-cultured supernatant. Healthy people were included to test the above indexes. The results showed that the mRNA expression of PBMNC T-bet, STAT4, T-bet/GATA-3 ratio, Th1 proportion, Th1/Th2 ratio and levels of IFN-γ and IL-12 in PBMNC-cultured supernatant of CAA patients were significantly higher than those of healthy people (p < 0.01). After treating with CsA for 6 months of CsA treatment, expression of T-bet, STAT4, T-bet/GATA-3 ratio, Th1 proportion, IFN-γ and IL-12 levels were lower than before, however, the expression of T-bet, STAT4, T-bet/GATA-3 ratio, Th1 proportion and IFN-γ had not been reduced to normal state. Compared to healthy people, no significant difference existed in the mRNA expression of GATA-3, STAT6, Th2 proportion, as well as level of IL-4 before and after treatment (p>0.05). It is concluded that the abnormal activation of IFN-γ/T-bet and IL-12/STAT4 pathways, as well as Th balance deviating to Th1 excursion play vital roles in the immunological pathogenesis of AA. CsA lowers the abnormal activation of IFN-γ/T-bet and IL-12/STAT4 pathways to correct Th1 hyperpolarization, which may reduce the abnormally activated cell-mediated immunity and relax hematopoietic depression of AA patients.
Sujets)
Adolescent , Adulte , Sujet âgé , Femelle , Humains , Mâle , Adulte d'âge moyen , Jeune adulte , Anémie aplasique , Traitement médicamenteux , Allergie et immunologie , Métabolisme , Études cas-témoins , Ciclosporine , Pharmacologie , Facteur de transcription GATA-3 , Métabolisme , Interféron gamma , Métabolisme , Interleukine-12 , Métabolisme , Interleukine-4 , Métabolisme , Facteur de transcription STAT-4 , Métabolisme , Facteur de transcription STAT-6 , Métabolisme , Transduction du signal , Protéines à domaine boîte-T , Métabolisme , Lymphocytes auxiliaires Th1 , Lymphocytes auxiliaires Th2Résumé
The aim of this study was to find new idea for clinical treatment of aplastic anemia. Immune-mediated aplastic anemia mice were developed, IL-3 in the supernatant with PHA stimulating splenic cells was detected by ELISA, semi-quantiting analysis of IL-3R was performed by point hybridization. The results showed that the IL-3 level in the supernatant with PHA stimulating splenic cells of immune-mediated aplastic anemia mice was higher than controls, difference between them was significant (P <0.001), while amount of IL-3 receptor by semi-quantiting analysis was lower than control significantly. In conclusion, the IL-3 receptor expression level is important for pathogenesis and treatment strategy of aplastic anemia.