[Inhibition of culture supernatant of mesenchymal stem cells on macrophages RAW264.7 activated by soluble egg antigen of Schistosoma japonicum].

To observe the inhibitive effect of rat mesenchymal stem cells (MSC) culture supernatant on macrophages activated by soluble egg antigen (SEA) of Schistosoma japonicum. To select optimal SEA effecting concentration and time, macrophages RAW264.7 were induced by 5, 10, 20 or 40 microg/ml SEA for 12 h, or by 20 microg/ml SEA for 4, 8, 12 or 24 h before examination of TNF-alpha mRNA by RT-PCR. Macrophages were divided into five groups, i.e. negative control group, SEA group, SEA+MSC supernatant group (MSC group), SEA+NRK-52E supernatant group (NRK-52E group) and SEA+DMEM group (DMEM group). Except negative control group, macrophages in other four groups were induced by 20 microg/ml SEA for 12 h. SEA was then removed from MSC group, NRK-52E group and DMEM group and replaced with MSC supernatant, NRK-52E supernatant and DMEM, respectively. Morphology of macrophages in each group was observed by microscope after cultured with supernatant for 12 h. TNF-alpha mRNA in macrophages was detected by real-time quantitative PCR after cultured with supernatant for 12 h and 24 h. TGF-beta1 in macrophages was observed by Western blotting analysis after cultured with supernatant for 12 h. Macrophage proliferation was tested by MTT method after cultured with supernatant for 24 h and 48 h. The optimal SEA concentration and time for macrophage activation was 20 microg/ml and 12 h, respectively. Compared with SEA group, NRK-52E group, and DMEM group, macrophages in MSC group were round and small with less pseudopodia after cultured with supernatant for 12 h. TNF-alpha mRNA after cultured with MSC supernatant for 12 h and 24 h was (1.0 +/- 0.4) and (1.0 +/- 0.5) fold of negative control group, respectively, significantly less than NRK-52E group [(10.4 +/- 3.9) and (16.5 +/- 5.0) fold] (12 h: P < 0.05; 24 h: P < 0.01) and DMEM group [(6.0 +/- 2.1) and (2.4 +/- 0.7) fold] (P < 0.05). The grey density image analysis of TGF-beta1/GAPDH was 0.31 +/- 0.10 in MSC group, much lower than 0.88 +/- 0.10 in NRK-52E group (P < 0.01) and 0.58 +/- 0.06 in DMEM group (P < 0.05) after cultured with supernatant for 12 h. After 48 h culture, A490 of macrophages in MSC group was 0.22 +/- 0.05, much lower than 0.53 +/- 0.02 in NRK-52E group and 0.31 +/- 0.03 in DMEM group (P < 0.05). MSC supernatant can inhibit activation and proliferation of macrophages which were induced by SEA of S. japonicum.