Involvement of graft-derived interleukin-15 in islet allograft rejection in mice.

The possibility that islets play a role in graft rejection during islet transplantation for type-1 diabetes patients holds promise for ex vivo islet manipulation and for specific anti-rejection therapy. Interleukin (IL)-15 is a T cell growth factor and chemoattractant that is expressed by non-T cells. Intragraft expression of IL-15 is elevated during acute rejection in patients and in mice, and systemic blockade of IL-15 in mice prolongs allograft survival.

CD40 ligation enhances IL-15 production by tubular epithelial cells.

Interleukin-15 (IL-15) is a potent T-cell growth factor and activator. Acute rejection of kidney allografts strongly correlated with elevated IL-15 mRNA in the graft. A role in the rejection process is also suggested for the interaction between CD40 ligand (CD154) expressed on membranes of activated T cells and its receptor (CD40).