OBJECTIVETo explore the changes of regulatory T (Treg) cells and Th17 cells in a novel mouse severe aplastic anemia (SAA) model induced by interferon-γ (IFN-γ) combined with busulphan (BU), and to demonstrate the rationality of the model in immunology level.

METHODSThe BALB/c female mice SAA model was constructed by intraperitoneal injection with IFN-γ and intragastric administration with BU (combined group), with BU group, IFN-γ group and normal group as controls. After collecting the mononuclear cells in the peripheral blood (PB) and spleen of mice in each group, the percentage of CD4(+)CD25(+)FOXP3(+) Treg cells and Th17 cells in the mononuclear cells were detected by flow cytometry(FCM), and to analyze the changes.

RESULTSThe percentage of the Treg cells in PB and spleen was (3.19 ± 0.76)% and (4.77 ± 1.05)% respectively in combined group, being significantly lower than in other three groups (all P < 0.01). The percentage of the Th17 cells in PB and spleen was (2.07 ± 0.12)% and (3.18 ± 0.46)% respectively in combined group, being significantly higher than that in other three groups (P < 0.05 and 0.01, respectively).

CONCLUSIONSLower Treg cells and higher Th17 cells was found in the novel mouse SAA model induced by IFN-γ combined with BU, which demonstrates that this SAA model may be more close to the human immune-mediated marrow failure.