Heme oxygenase-1 protects INF-gamma primed endothelial cells from Jurkat T-cell adhesion.
OBJECTIVE
The heme oxygenase-1 (HO-1) system is associated with the rate-limiting step of conversion of heme, one of the most critical roles in cytoprotective mechanisms. Our study investigated its potential role in protection of endothelial cells from T cells.


METHODS
The recombinant plasmid pcDNA3-HO-1 was transfected into endothelial cells. Indirect fluorescent staining was used to examine the expression of HO-1 protein. Then endothelial cells primed by INF-gamma were mixed in culture with Jurkat T cells labeled with carboxyfluorescein diacetate succinimidyl ester (CFSE). The number of adhesive Jurkat T cells was determined using FACS to evaluate the adhesion effect. After being cultured with endothelial cells, the cell cycle of Jurkat T cells was detected using FACS.


RESULTS
Expression of HO-1 on endothelial cells conferred significant protection against Jurkat T-cell-mediated adhesion. The rate of Jurkat T-cell adhesions was reduced to 19.06%, in contrast with 31.42% in the control group (P<.05). After using ZnPP, an inhibitor of HO-1, the rate of Jurkat T-cell adhesion recovered to 29.08%. The binding activities between endothelial cells and Jurkat T cells was blocked by HO-1 expression. The proliferation of Jurkat T cells was inhibited after culture with endothelial cells, which had been transfected with HO-1, which blocked cell cycle entry of T cells. More than 60% of Jurkat T cells remained in G0/G1 compared with 40% among the control group.


CONCLUSIONS
HO-1 directly protected endothelial cells primed by INF-gamma from Jurkat T cells and down-regulated the expression of HLA-DR on the surface of endothelial cells. These results indicated that transgenic expression of HO-1 may be useful to prevent lymphocytes from responding to endothelial cells.
Du
D
D
Institute of Organ Transplantation, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China. dudunfeng@163.com
Chang
S
S
Chen
B
B
Zhou
H
H
Chen
Z K
ZK
D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects*; D017931:DNA Primers; D004730:Endothelium, Vascular / Q000502:physiology*; D005452:Fluoresceins; D005786:Gene Expression Regulation / Q000276:immunology; D006684:HLA-DR Antigens / Q000235:genetics; D051547:Heme Oxygenase-1 / Q000235:genetics* / Q000627:therapeutic use*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D019169:Jurkat Cells / Q000502:physiology*; D016133:Polymerase Chain Reaction; D051381:Rats; D017208:Rats, Wistar; D013154:Spleen / Q000201:enzymology; D013388:Succinimides
C087165:5-(6)-carboxyfluorescein diacetate succinimidyl ester; D017931:DNA Primers; D005452:Fluoresceins; D006684:HLA-DR Antigens; D013388:Succinimides; D007371:Interferon-gamma; D051547:Heme Oxygenase-1