OBJECTIVETo observe the effect of Shenghua Decoction in reversing IFN-gamma inhibition induced by methotrexate (MTX).

METHODSPregnant Balb/C mice were randomly divided into the negative control group, Shenghua Decoction group, the MTX control group, and the MTX combined with Shenghua Decoction group. Pregnant mice in the 4 groups were respectively treated with normal saline (NS), Shenghua Decoction, MTX, and MTX combined with Shenghua Decoction for 7 successive days. Then mice were sacrificed 1 h after the last administration. Living fetus and dead fetus were counted to assess meto-maternal rejection. The percentages of interferon-gamma+(IFN-gamma+) and CD3+CD+IFN-gamma+ cells in spleen lymphocytes of pregnant mice were double stained for cytometric analysis. At the same time IFN-gamma message ribonucleic acid (mRNA) in the spleen mononuclear cells was detected by reverse transcription polymerase chain reaction (RT-PCR).

RESULTSCompared with the negative control group, the number of dead fetus increased significantly after the administration of Shenghua Decoction (P > 0.05). The percentages of IFN-gamma+ and CD3+CD4+IFN-gamma+ in spleen mononuclear cells were elevated by 28.81% and 35.61% respectively (both P < 0.05). IFN-gamma mRNA expression increased (P < 0.05). After the administration of MTX, the number of dead fetus increased significantly. The percentages of IFN-gamma+ and CD3+CD4+IFN-gamma+ in spleen mononuclear cells were reduced by 24.23% and 26.77% respectively compared with the negative control group. Besides, the expression of IFN-gamma mRNA decreased obviously (P < 0.05). However, after the administration of MTX in combination of Shenghua Decoction, the number of dead fetus was further added. Moreover, the percentages of IFN-gamma+ and CD3+CD4+IFN-gamma+ cells obviously increased. The increment was 64.96% and 71.38% respectively when compared with the MTX group, and the expression of IFN-gamma mRNA was obviously up-regulated (P < 0.05).

CONCLUSIONShenghua Decoction showed reversing effect on MTX induced IFN-gamma inhibition by promoting the differentiation of IFN-gamma+Th1 subpopulation and up-regulating IFN-gamma expression, thus promoting the feto-maternal immunological rejection.