Interactions between NKT cells and Tregs are required for tolerance to combined bone marrow and organ transplants BLOOD Hongo, D., Tang, X., Dutt, S., Nador, R. G., Strober, S. 2012; 119 (6): 1581-1589

Abstract

We used a model of combined bone marrow and heart transplantation, in which tolerance and stable chimerism is induced after conditioning with fractionated irradiation of the lymphoid tissues and anti-T-cell antibodies. Graft acceptance and chimerism required host CD4(+)CD25(+) Treg production of IL-10 that was in-turn enhanced by host invariant natural killer (NK) T-cell production of IL-4. Up-regulation of PD-1 on host Tregs, CD4(+)CD25(-) conventional T (Tcon) cells, and CD8(+) T cells was also enhanced by NKT cell production of IL-4. Up-regulated PD-1 expression on Tregs was linked to IL-10 secretion, on CD8(+) T cells was linked to Tim-3 expression, and on CD4(+) Tcon cells was associated with reduced IFN? secretion. Changes in the expression of PD-1 were induced by the conditioning regimen, and declined after bone marrow transplantation. In conclusion, NKT cells in this model promoted changes in expression of negative costimulatory receptors and anti-inflammatory cytokines by Tregs and other T-cell subsets in an IL-4-dependent manner that resulted in tolerance to the bone marrow and organ grafts.

View details for DOI 10.1182/blood-2011-08-371948

View details for Web of Science ID 000300420900035

View details for PubMedID 22174155

View details for PubMedCentralID PMC3286219