IL-10 Enhances Promoter Activity of ILT4 Gene and Up-regulates Its Expression in THP-1 Cells
10.1007/s11596-010-0548-8
- Author:
XU XIAOLI
1
;
ZOU PING
;
CHEN LIJUAN
;
JIN GUANNAN
;
ZHOU HAO
Author Information
1. Institute of Hematology,Department of Obstetrics and Gynecology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Keywords:
IL-10;
ILT4;
THP-1;
immune tolerance;
promoter
- From:
Journal of Huazhong University of Science and Technology (Medical Sciences)
2010;30(5):594-598
- CountryChina
- Language:Chinese
-
Abstract:
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 ofpGL3-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.
