Rapamycin affect the apoptosis of splenic CD4+CD25+ regulatory T cells of mouse severe aplastic anemia model
10.3760/cma.j.issn.0253-2727.2018.03.005
- VernacularTitle: 雷帕霉素对重型再生障碍性贫血模型小鼠脾脏CD4+CD25+ T细胞凋亡的影响
- Author:
Zenghua LIN
1
;
Hong LIU
;
Li ZHU
;
Xi YANG
;
Yaping ZHANG
;
Juan QIAN
;
Haiyan LIU
Author Information
1. Department of Hematology, Affiliated Hospital of Nantong University, Nantong 226001, China
- Publication Type:Journal Article
- Keywords:
Anemia, aplastic;
T-lymphocytes, regulatory;
Rapamycin;
Apoptosis;
Forkhead box P3
- From:
Chinese Journal of Hematology
2018;39(3):196-201
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the effects and possible mechanism of rapamycin (RAPA) on apoptosis of CD4+CD25+ Tregs from the mouse severe aplastic anemia (SAA) model.
Methods:The BALB/c female SAA model mice were induced by interferon-gamma in combination with busulphan. The SAA model mice were intraperitoneal injection with RAPA at daily dose of 0.5 mg/kg for 5 days (the RAPA-treated group, n=15) in the SAA group (n=15) and the un-treated group (n=15) were control. Bone marrow hematopoiesis changes were observed by the patho-morphological examination of femurs. The mononuclear cells of the peripheral blood and spleen were subjected to assess the intracellular Foxp3 expression in CD4+CD25+ Tregs by flow cytometry (FCM). In addition, after being pured by immunomagnetic beads, the splenic CD4+CD25+ Tregs was subjected to assess apoptosis by FCM and the Akt and Stat3 phosphorylation by using of western blot.
Results:The patho-morphological examination of femurs showed normal marrow cell proliferation in un-treated group and hypocellularity in both SAA group and RAPA-treat group, with an increase in the number of fat cells. The bone marrow hematopoietic tissue ratio in RAPA-treat group was higher than SAA group [(9.75±1.83)% vs (7.00±2.00)%, Δx=2.15% (95%CI 0.15%-5.35%), P=0.037]. In the SAA group, FCM analysis showed down-expression of Foxp3 in CD4+CD25+ Tregs compared with the un-treated group. However, after treatment with RAPA, the expression of Foxp3 in CD4+CD25+ Tregs was increased (P<0.017). Compared with the un-treated group, increased CD4+CD25+ Tregs apoptosis [(19.84±1.39)% vs (29.85±2.72)%] with increased Akt phosphorylation accompanied by increased Stat3 phosphorylation was found in SAA group (P<0.05, respectively). On the contrary, RAPA-treated group exhibited CD4+ CD25+ Tregs with a reduction in apoptosis rate [(22.39±3.71)%], Akt phosphorylation and Stat3 phosphorylation compared with the SAA group (P<0.05, respectively).
Conclusion:These results indicate that RAPA may increase the expression of Foxp3 by down-regulation the levels of Akt and Stat3 phosphorylation and reduce apoptosis in splenic CD4+CD25+ Tregs from the mice model of SAA.
