TY - JOUR
T1 - Hepatic Infiltrates in Operational Tolerant Patients After Liver Transplantation Show Enrichment of Regulatory T Cells Before Proinflammatory Genes Are Downregulated
AU - Taubert, Richard
AU - Danger, Richard Amaud Eric David
AU - Londono, María-Carlota
AU - Christakoudi, Sofia
AU - Martinez-Picola, Marta
AU - Rimola, Antoni
AU - Manns, Michael
AU - Sanchez Fueyo, Alberto
AU - Jaeckel, Elmer
PY - 2016/3/30
Y1 - 2016/3/30
N2 - Immunosuppression can be discontinued from selected and stable patients after liver transplantation resulting in spontaneous operational tolerance (SOT), although the underlying mechanisms remain elusive. Thus, we analyzed serial liver biopsy specimens from adult liver recipients enrolled in a prospective multicenter immunosuppression withdrawal trial that used immunophenotyping and transcriptional profiling. Liver specimens were collected before the initiation of weaning, at the time of rejection, or at 1 and 3 years after complete drug discontinuation. Unexpectedly, the tolerated grafts developed portal tract expansion with increased T cell infiltration after immunosuppression withdrawal. This was associated with transient and preferential accumulation of CD4+FOXP3+ cells and a trend toward upregulation of immune activation and regulatory genes, without signs of rejection. At the same time, no markers of endothelial damage or activation were noted. Portal infiltrates persisted at 3 years but were characterized by decreased expression of genes associated with chronic immunological damage. Further, SOT was not associated with a progressive liver fibrosis up to 5 years. These data suggest that SOT involves several mechanisms: a long-lasting local immune cell persistence with a transient regulatory T cells accumulation followed by a downregulation of immune-activated genes over years. These results have important implications for designs and follow-up of weaning trials.
AB - Immunosuppression can be discontinued from selected and stable patients after liver transplantation resulting in spontaneous operational tolerance (SOT), although the underlying mechanisms remain elusive. Thus, we analyzed serial liver biopsy specimens from adult liver recipients enrolled in a prospective multicenter immunosuppression withdrawal trial that used immunophenotyping and transcriptional profiling. Liver specimens were collected before the initiation of weaning, at the time of rejection, or at 1 and 3 years after complete drug discontinuation. Unexpectedly, the tolerated grafts developed portal tract expansion with increased T cell infiltration after immunosuppression withdrawal. This was associated with transient and preferential accumulation of CD4+FOXP3+ cells and a trend toward upregulation of immune activation and regulatory genes, without signs of rejection. At the same time, no markers of endothelial damage or activation were noted. Portal infiltrates persisted at 3 years but were characterized by decreased expression of genes associated with chronic immunological damage. Further, SOT was not associated with a progressive liver fibrosis up to 5 years. These data suggest that SOT involves several mechanisms: a long-lasting local immune cell persistence with a transient regulatory T cells accumulation followed by a downregulation of immune-activated genes over years. These results have important implications for designs and follow-up of weaning trials.
U2 - 10.1111/ajt.13617
DO - 10.1111/ajt.13617
M3 - Article
SN - 1600-6135
VL - 16
SP - 1285
EP - 1293
JO - American Journal of Transplantation
JF - American Journal of Transplantation
IS - 4
ER -