In this paper, toll-like receptor expression pattern in monocytes-derived macrophages by lipopolysaccharid （LPS） stimulation was examined. Jugular venous blood samples from 4 Japanese calves were obtained and the peripheral blood mononuclear cells （PBMC） were isolated. The PBMC were cultured for 7 d so as to collect monocytes-derived macrophages in Repcell. The PBMC were stimulated by LPS for 24 h and the mRNA expression pattern of TLR and cytokines in monocytes-derived macrophages （Mod-Mφ） was analyzed. Results showed that LPS stimulation of Mod-Mφ could increase the mRNA levels of the genes of TNF-α, IL-6, and IL-8. In addition, the mRNA levels of the genes of TNF-α and IL-6 in the group of LPS stimulation were most significantly （P 〈 0.01） higher than those in control group and the mRNA levels of TLR1, 3, 5, 8, and 10 were significantly （P 〈 0.05） decreased after LPS stimulation. There was no difference in the mRNA expressions of TLR2, 4, 6, and 7 between the groups of the control and LPS stimulation. Besides, expression of TLR9 was not found. It suggested that monocytes-derived macrophages could respond to LPS and they might take an important role in the innate immunity. The important function of the cells might contribute to better disease treatment.
In this experiment Toll-like receptor expression pattern in monocytes and monocyte-derived macrophages by lipopolysaccharide （LPS） stimulation was examined. Jugular venous blood was collected from four Japanese calves, and the peripheral blood mononuclear cells （PBMCs） were isolated. The cells were directly used for collecting monocytes by magnetic cell sorting or cultured for 7 days to collect monocyte-derived macrophages in Repcell. Then we analyzed the mRNA expression pattern of TLRs and cytokines in monocytes and monocyte-derived macrophages after LPS stimulation for 24 h. LPS stimulation of both monocytes and monocyte-derived macrophages resulted in an increase in the levels of mRNA transcripts for TNF-α IL-6 and IL-8. Moreover, TNF-α and IL-6 mRNA expressions were significantly augmented by LPS stimulation in monocyte-derived macrophages. TLRs mRNA expressions were unchanged after LPS stimulation of monocytes, while TLRs mRNA expressions in monocyte-derived macrophages were complicated. TLR1, 3, 5, 8 and 10 were significantly decreased after LPS stimulation and there were no differences in the mRNA expressions of TLR2, 4, 6 and 7 between the groups of control and LPS stimulation. Besides, no expression of TLR9 was found. As antigen presenting cells, monocytes and monocyte-derived macrophages respond differently to LPS, so they may have different functions in the innate immune system.
