Molecular characterization of rat leukocyte P-selectin glycoprotein ligand-1 and effect of its blockade: protection from ischemia-reperfusion injury in liver transplantation.
P-selectin glycoprotein ligand-1 (PSGL-1) mediates the initial tethering of leukocytes to activated platelets and endothelium. We report molecular cloning and characterization of the rat PSGL-1 gene. A neutralizing Ab was generated, and its binding epitope was mapped to the N-terminal binding region of rat PSGL-1. We examined the effects of early PSGL-1 blockade in rat liver models of cold ischemia, followed by ex vivo reperfusion or transplantation (orthotopic liver transplantation (OLT)) using an anti-PSGL-1 Ab with diminished Fc-mediated effector function. In the ex vivo hepatic cold ischemia and reperfusion model, pretreatment with anti-PSGL-1 Ab improved portal venous flow, increased bile production, and decreased hepatocellular damage. Rat pretreatment with anti-PSGL-1 Ab prevented hepatic insult in a model of cold ischemia, followed by OLT, as assessed by 1) decreased hepatocellular damage (serum glutamic oxaloacetic transaminase/glutamic-pyruvic transaminase levels), and ameliorated histological features of ischemia/reperfusion injury, consistent with extended OLT survival; 2) reduced intrahepatic leukocyte infiltration, as evidenced by decreased expression of P-selectin, ED-1, CD3, and OX-62 cells; 3) inhibited expression of proinflammatory cytokine genes (TNF-alpha, IL-1beta, IL-6, IFN-gamma, and IL-2); and 4) prevented hepatic apoptosis accompanied by up-regulation of antiapoptotic Bcl-2/Bcl-xL protective genes. Thus, targeting PSGL-1 with a blocking Ab that has diminished Fc-mediated effector function is a simple and effective strategy that provides the rationale for novel therapeutic approaches to maximize the organ donor pool through the safer use of liver transplants despite prolonged periods of cold ischemia.
Tsuchihashi
Sei-ichiro
S
Dumont-University of California Transplant Center, Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA.
Fondevila
Constantino
C
Shaw
Gray D
GD
Lorenz
Meike
M
Marquette
Kimberly
K
Benard
Susan
S
Shen
Xiu-Da
XD
Ke
Bibo
B
Busuttil
Ronald W
RW
Kupiec-Weglinski
Jerzy W
JW
D000595:Amino Acid Sequence; D000818:Animals; D019138:Antibodies, Blocking / Q000494:pharmacology*; D017209:Apoptosis / Q000276:immunology; D001483:Base Sequence; D001666:Binding Sites, Antibody / Q000235:genetics; D015153:Blotting, Western; D015698:Genomic Library; D006085:Graft Survival / Q000187:drug effects / Q000276:immunology; D006801:Humans; D020287:In Situ Nick-End Labeling; D007962:Leukocytes / Q000276:immunology* / Q000378:metabolism; D016031:Liver Transplantation / Q000276:immunology* / Q000473:pathology; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000276:immunology; D008969:Molecular Sequence Data; D051381:Rats; D011917:Rats, Inbred Lew; D015427:Reperfusion Injury / Q000276:immunology / Q000473:pathology / Q000517:prevention & control*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid
D019138:Antibodies, Blocking; D008562:Membrane Glycoproteins; C084882:P-selectin ligand protein