Solid Organ Transplantation Irrevocably Alters Tissue-Resident Graft Immunity

Tissue integrity and repair is assisted by tissue-resident leukocytes, which also provide immediate responses to infection. It is unclear to what extent tissue-resident cells are perturbed following solid organ transplantation. For the first time, we report on the varied fates of 13 subsets of B, T and ILC lymphocytes after murine liver and heart transplantation in the absence of tissue mismatch and immunosuppression . Strikingly, donor-derived unconventional lymphocytes are predominantly maintained in livers, but not hearts, as long-term tissue-resident and self-renewing populations. In contrast, donor conventional lymphocytes are rapidly displaced by recipient populations, but this does not occur in the absence of recipient T and B cells. Overall, infiltrating recipient cells fail to recreate the native organ’s phenotypically diverse tissue-resident lymphocyte composition. These changes in post-transplant immunity are likely to leave the graft vulnerable to infection and impair long-term graft function.