[Effect of hypoxia/reoxygenation (H/R) on expression of MICA and MICB in human hepatocytes].
OBJECTIVE
It has been found that the human major histocompatibility complex class I chain-related antigen A,B (MICA,B), the ligand for NKG2D (an activating receptor of NK cell, CD8+ cell and gammadelta T cell), could be induced by cellular stress. The purpose of this study is to investigate whether Hypoxia/Reoxygenation could upregulate expression of MICA,B gene in human hepatocytes (HL-7702).


METHODS
The model of cell hypoxia/reoxygenation was used to mimic ischemia/reperfusion injury (IRI) of graft organ. The human hepatocytes were exposed to hypoxic condition for 15 h under 1% O2, 94% N2 and 5% CO2, then reoxygenated for 2 h, 4 h, 6 h, 12 h and 24 h separately under normal condition. The levels of MICA and MICB mRNA were measured by semi-quantitative RT-PCR. The surface expression of MIC were detected by immunofluorescence with a rabbit polyclonal antibody which is recommended for the detection of MICA,B of human origin simultaneously.


RESULTS
Hpoxia/Reoxygenation increased the levels of MICA,B in hypoxic hepatocytes.


CONCLUSIONS
In this article is firstly reported that H/R could increased the levels of MICA,B in human hepatocytes, yet the meachinsm is unknown. The upregulated expression of NKG2D ligand possibly activates NK cells and is hence associated with transplantation.
He
Ying
Y
Lab of Transplant Engineering and Immunology, West China Hospital, Sichuan University, Chengdu 610041, China.
Li
You-ping
YP
Li
Sheng-fu
SF
Long
Dan
D
D015687:Cell Hypoxia / Q000187:drug effects; D002478:Cells, Cultured; D005786:Gene Expression Regulation; D022781:Hepatocytes / Q000166:cytology / Q000378:metabolism*; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D008565:Membrane Proteins; D018384:Oxidative Stress; D010100:Oxygen / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics
D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A; C098080:MICB antigen; D008565:Membrane Proteins; D012333:RNA, Messenger; D010100:Oxygen