Journal of Huazhong University of Science and Technology [Medical Sciences]

, Volume 30, Issue 5, pp 594–598

IL-10 enhances promoter activity of ILT4 gene and up-regulates its expression in THP-1 cells

Authors

  • Xiaoli Xu徐小丽
    • Institute of HematologyUnion Hospital, Tongji Medical College, Huazhong University of Science and Technology
  • Ping Zou邹 萍
    • Institute of HematologyUnion Hospital, Tongji Medical College, Huazhong University of Science and Technology
  • Lijuan Chen陈莉娟
    • Department of Obstetrics and GynecologyUnion Hospital, Tongji Medical College, Huazhong University of Science and Technology
  • Guannan Jin靳冠楠
    • Institute of HematologyUnion Hospital, Tongji Medical College, Huazhong University of Science and Technology
    • Institute of HematologyUnion Hospital, Tongji Medical College, Huazhong University of Science and Technology
Article

DOI: 10.1007/s11596-010-0548-8

Cite this article as:
Xu, X., Zou, P., Chen, L. et al. J. Huazhong Univ. Sci. Technol. [Med. Sci.] (2010) 30: 594. doi:10.1007/s11596-010-0548-8

Summary

This study examined the effect of IL-10 on immunoglobulin-like transcript (ILT4) expression of human monocytic leukemic cell line THP-1, especially the role of the ILT4 promoter activity. ILT4 promoter area was amplified by PCR, and was cloned into the eukaryotic expressing vector pGL3-Basic. The pGL3-ILTP obtained was tested by double endonuclease digestion and sequencing. Then, the recombinant plasmid was transfected into THP-1 cells by using lipofectamine. After culture with IL-10 for 12 h, the mRNA extracted from THP-1 cells was detected by RT-PCR and the protein was detected by FACS. The dual-luciferase reporter assay system was employed to detect the activity of ILT4 promoter with or without IL-10. The results showed that the activity of pGL3-ILTP was significantly increased and was more than ten times that of pGL3-Basic cells. After culture with IL-10 for 12 h, the expression of ILT4 protein and its mean fluorescence intensity (MFI) were increased. Moreover, the mRNA was remarkably higher than that of the control group. Dual-luciferase reporter assay revealed that ILT4 promoter was much more activated after being treated with IL-10. We were led to conclude that pGL3-ILTP containing ILT4 promoter was constructed successfully. The expression of ILT4 could be up-regulated by IL-10 both at the transcriptional and translational level. Furthermore, ILT4 promoter could be much more active after addition of IL-10. This study suggests that IL-10 up-regulates ILT4 expression on monocytes via increasing ILT4 gene promoter activity, which may have implication for inducing transplantation tolerance in clinical practice.

Key words

IL-10 ILT4 THP-1 immune tolerance promoter

Copyright information

© Huazhong University of Science and Technology and Springer-Verlag Berlin Heidelberg 2010