Thymic rejuvenation via FOXN1reprogrammed embryonic fibroblasts (FREFs) to counteract age-related inflammation

Jiyoung Oh, Weikan Wang, Rachel Thomas, Dong Ming Su

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


Age-associated systemic, chronic inflammation is partially attributed to increased self-autoreactivity, resulting from disruption of central tolerance in the aged, involuted thymus. This involution causally results from gradually decreased expression of the transcription factor FOXN1 in thymic epithelial cells (TECs), whereas exogenous FOXN1 in TECs can partially rescue age-related thymic involution. TECs induced from FOXN1-overexpressing embryonic fibroblasts can generate an ectopic de novo thymus under the kidney capsule, and intrathymic injection of naturally young TECs can lead to middle-aged thymus regrowth. Therefore, as a thymic rejuvenation strategy, we extended these 2 findings by combining them with 2 types of promoter-driven (Rosa26CreERT and FoxN1Cre) Cre-mediated FOXN1-reprogrammed embryonic fibroblasts (FREFs). We engrafted these FREFs directly into the aged murine thymus. We found substantial regrowth of the native aged thymus with rejuvenated architecture and function in both males and females, exhibiting increased thymopoiesis and reinforced thymocyte negative selection, along with reduced senescent T cells and autoreactive T cell-mediated inflammation in old mice. Therefore, this approach has preclinical significance and presents a strategy to potentially rescue decreased thymopoiesis and perturbed negative selection to substantially, albeit partially, restore defective central tolerance and reduce subclinical autoimmune symptoms in elderly people.

Original languageEnglish
Article numbere140313
JournalJCI Insight
Issue number18
StatePublished - Aug 2020


Dive into the research topics of 'Thymic rejuvenation via FOXN1reprogrammed embryonic fibroblasts (FREFs) to counteract age-related inflammation'. Together they form a unique fingerprint.

Cite this