T cell progenitor therapy–facilitated thymopoiesis depends upon thymic input and continued thymic microenvironment interaction

• DOI: 10.1172/jci.insight.92056
• Publication Date: 2017-05-17T15:00:52Z
• Authors: Michelle J. Smith; Dawn K. Reichenbach; Sarah L. Parker; Megan J. Riddle; Jason Mitchell; Kevin C. Osum; Mahmood Mohtashami; Heather E. Stefanski; Brian T. Fife; Avinash Bhandoola; Kristin A. Hogquist; Georg A. Holländer; Juan Carlos Zúñig...; Jakub Tolar; Bruce R. Blazar
• Keywords: Thymocyte; Lymphopoiesis

Infusion of in vitro-derived T cell progenitor (proT) therapy with hematopoietic stem transplant aids the recovery thymus damaged by total body irradiation. To understand interaction between proTs and thymic microenvironment, WT mice were lethally irradiated given cell-deficient (Rag1-/-) marrow vitro-generated proTs, limiting mature development to infused proTs. ProTs within host led a significant increase epithelial cells (TECs) day 21 after transplant, increasing actively cycling TECs. Upon egress (day 28), proT TEC effects lost, suggesting that continued signaling from is required sustain cellularity. Thymocytes increased significantly 21, followed improvement numbers periphery 35. This protective surge was temporary, receding 60. Double-negative 2 (DN2) selectively thymocyte number, while DN3 preferentially TECs spleen persisted at These findings highlight importance proliferation survival maturation stage has unique on thymopoiesis peripheral recovery.