Session
Session 3
Board Number
55
The Role of Exosomes in the Maintenance of Transplant Tolerance
Achieving immune tolerance to allografts is an important end goal in transplantation. A “vaccine” of apoptotic donor leukocytes (ADL) accompanied by short-term immunosuppressants prior to transplant has been shown to induce long-term tolerance to islet allografts in vivo. Here, I examined the effect of circulating exosomes in the maintenance of tolerance following ADL treatment. Cell cultures of PBMCs treated with serum-derived exosomes from ADL-treated Rhesus monkeys increased Treg cell frequency in vitro compared with treatment of exosomes from monkeys undergoing rejection, but Tr1 cell populations appear not to be affected. Further investigation is needed into the mechanism that these exosomes may contribute to a tolerogenic response