Hepatitis C virus infection after liver transplantation is associated with lower levels of activated CD4(+)CD25(+)CD45RO(+)IL-7ralpha(high) T cells.
The expression of interleukin 7 receptor alpha(high) (IL-7Ralpha(high)) discriminates between activated CD25(+)CD45RO(+)CD4(+) T cells [IL-7Ralpha(high) and forkhead box P3-negative (FoxP3(-))] and regulatory T cells (IL-7Ralpha(low) and FoxP3(+)). The IL-7Ralpha(high)CD25(+)CD45RO(+)CD4(+)FoxP3(-) T cell population has been shown to be expanded in the blood and tissues of patients after kidney transplantation and to contain alloreactive T cells (activated T cells). In the present study, we analyzed the distribution of IL-7Ralpha(high)CD25(+)CD45RO(+)CD4(+)FoxP3(-) T cells in the blood of 53 patients after liver transplantation. The IL-7Ralpha(high)CD25(+)CD45RO(+)CD4(+)FoxP3(-) T cell population was significantly expanded (P < 0.0001) in stable transplant recipients versus healthy donors. However, the magnitude of the expansion was significantly higher (P < 0.0001) in liver transplant recipients with no hepatitis C virus (HCV) infection in comparison with those with a preexisting HCV infection. Interestingly, effective suppression of HCV viremia after antiviral therapy was associated with an increase in the IL-7Ralpha(high)CD25(+)CD45RO(+)CD4(+)FoxP3(-) T cell population to levels comparable to those of liver transplant recipients not infected with HCV. The present results indicate that (1) the IL-7Ralpha(high)CD25(+)CD45RO(+)CD4(+)FoxP3(-) T cell population is expanded after liver transplantation, (2) it is a valuable immunological marker for monitoring activated and potential alloreactive CD4 T cells in liver transplantation, and (3) a preexisting HCV infection negatively influences the expansion of this population in liver transplant recipients.
Division of Immunology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland.
Donatella
D
Ciuffreda
Laura
L
Codarri
Leo
L
Buhler
Laure
L
Vallotton
Emiliano
E
Giostra
Gilles
G
Mentha
Philippe
P
Morel
Giuseppe
G
Pantaleo
Manuel
M
Pascual
D000328:Adult; D000368:Aged; D000998:Antiviral Agents / Q000627:therapeutic use; D016022:Case-Control Studies; D015536:Down-Regulation; D005260:Female; D019698:Hepatitis C, Chronic / Q000188:drug therapy / Q000276:immunology*; D006801:Humans; D053699:Interleukin-7 Receptor alpha Subunit / Q000378:metabolism*; D016031:Liver Transplantation; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000378:metabolism*; D055815:Young Adult
D000998:Antiviral Agents; D053699:Interleukin-7 Receptor alpha Subunit