The TLR Expression Pattern on Monocyte-Derived Macrophages for Lipopolysaccharid Stimulation of Calves

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.