Hepatocyte transplantation-induced liver inflammation is driven by cytokines-chemokines associated with neutrophils and Kupffer cells.
OBJECTIVE
Hepatocyte transplantation-induced liver inflammation impairs cell engraftment. We defined whether proinflammatory cytokines and chemokines played roles in regulation of hepatocyte engraftment in the liver.


METHODS
We performed studies over up to 3 weeks in rat hepatocyte transplantation systems. Expression of 84 cytokine-chemokine genes was studied by quantitative real-time polymerase chain reactions. Expression of selected up-regulated genes was verified by immunohistochemistry. Hepatic recruitment of neutrophils was demonstrated by myeloperoxidase activity assays, and Kupffer cell activation was established by carbon phagocytosis assays. The role of neutrophils and Kupffer cells in regulating expression of cytokine-chemokine genes as well as cell engraftment was determined by cell depletion studies.


RESULTS
Within 6 hours after syngeneic cell transplantation, expression of 25 cytokine-chemokine genes increased by 2- to 123-fold, P < .05. These genes were largely associated with activated neutrophils and macrophages, including chemokine ligands, CXCL1, CXCL2, CCL3, CCL4; chemokine receptors, CXCR1 or CXCR2, CCR1, CCR2; and regulatory cytokines tumor necrosis factor alpha and interleukin-6. Inflammatory cells in the liver immunostained for CCR1, CCR2, CXCR1, and CXCR2, which indicated that up-regulated messenger RNA was appropriately translated. When neutrophils and Kupffer cells were depleted with neutrophil antiserum and gadolinium chloride, respectively, before transplanting cells, cell transplantation-induced cytokine-chemokine responses were attenuated. Virtually all abnormalities subsided in animals treated with neutrophil antiserum plus gadolinium chloride. Moreover, depletion of neutrophils or Kupffer cells improved engraftment of transplanted cells.


CONCLUSIONS
Cell transplantation-induced liver inflammation involves proinflammatory cytokine-chemokine systems capable of modulation by neutrophils and Kupffer cells. This offers new directions for optimizing cell therapy strategies.
Department of Medicine, Marion Bessin Liver Research Center, Diabetes Research Center and Cancer Research Center, Albert Einstein College of Medicine, Bronx, New York 10461, USA.
Natan
N
Krohn
Sorabh
S
Kapoor
Yuta
Y
Enami
Antonia
A
Follenzi
Sriram
S
Bandi
Brigid
B
Joseph
Sanjeev
S
Gupta
D000818:Animals; D018925:Chemokines / Q000235:genetics / Q000378:metabolism*; D016207:Cytokines / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D006505:Hepatitis / Q000209:etiology / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D022781:Hepatocytes / Q000637:transplantation*; D007728:Kupffer Cells / Q000378:metabolism / Q000473:pathology*; D008099:Liver / Q000378:metabolism / Q000473:pathology*; D018375:Neutrophil Activation; D009504:Neutrophils / Q000378:metabolism / Q000473:pathology*; D009195:Peroxidase / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D015854:Up-Regulation; D005723:gamma-Glutamyltransferase / Q000378:metabolism
D018925:Chemokines; D016207:Cytokines; D009195:Peroxidase; D005723:gamma-Glutamyltransferase