Ablation and regeneration of tolerance-inducing medullary thymic epithelial cells after cyclosporine, cyclophosphamide, and dexamethasone treatment

Anne Louise Fletcher, Tamara Eve Lowen, Samy Sakkal, Jessica Jane Reiseger, Maree Vanessa Hammett, Natalie Louise Seach, Hamish S Scott, Richard Lennox Boyd, Ann Patricia Chidgey

    Research output: Contribution to journalArticleResearchpeer-review

    46 Citations (Scopus)

    Abstract

    Immunosuppressive drugs and cytotoxic chemotherapy agents are designed to kill or suppress autoreactive, alloaggressive, or hyperinflammatory T cells, or disseminated malignancies. However, they also cause severe immunological side effects ranging from interrupted thymopoiesis and general immunodeficiency to, paradoxically, autoimmunity. Consistent with the cross-talk between thymocytes and stromal cells, we now show that these common therapeutic agents have major effects on murine thymic epithelial cells (TEC), crucially required to rebuild immunity posttreatment. We show that the immunosuppressant cyclosporine A, which has been linked to a thymus-dependent autoimmune syndrome in some patients, causes extensive loss of autoimmune regulator (Aire(+)) tolerance-inducing MHC class II(high) medullary TEC (mTEC(high)). Post-cyclosporine A, Aire expression was restored within 7 days. Full recovery of the mTEC(high) subset occurred within 10 days and was linked to a decrease in a relatively resistant MHC class II(low) mTEC subset (mTEC(low)), consistent with a previously described precursor-product relationship. Cyclophosphamide and dexamethasone caused more extensive ablation of thymocytes and stromal cells but again severely depleted tolerance-inducing mTEC(high). Together, these data show that Aire(+) mTECs are highly sensitive to damage and that mTEC regeneration follows a conserved pattern regardless of the treatment regimen used.
    Original languageEnglish
    Pages (from-to)823 - 831
    Number of pages9
    JournalJournal of Immunology
    Volume183
    Issue number2
    DOIs
    Publication statusPublished - 2009

    Cite this