CD4+ T cells in aged or thymectomized recipients of allogeneic stem cell transplantations

BACKGROUND: CD4+CD25highFOXP3+ regulatory T (Treg) cells, which include thymus-derived and peripherally induced cells, play a central role in immune regulation, and are therefore crucial to prevent graft-versus-host disease (GVHD). The increasing use of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for elderly patients with thymus regression, and our case of allo-HSCT shortly after total thymectomy, raised questions about the activity of thymus-derived Treg cells and peripherally induced Treg cells, which are otherwise indistinguishable. RESULTS: We found that despite pre-transplant thymectomy or older age, both naïve and effector Treg cells, as well as naïve and effector conventional T cells, proliferated in allo-HSCT recipients. Higher proportions of total Treg cells 1 month post allo-HSCT, and naïve Treg cells 1 year post allo-HSCT, appeared in patients achieving complete chimera without developing significant chronic GVHD, including our thymectomized patient, compared with patients who developed chronic GVHD. CONCLUSIONS: Treg cells that modulate human allogeneic immunity may arise peripherally as well as in the thymus of allo-HSCT recipients.

Bibliographic Details

Main Authors:	Takahashi,Hiroshi, Ikeda,Kazuhiko, Ogawa,Kazuei, Saito,Syunnichi, Ngoma,Alain M, Mashimo,Yumiko, Ueda,Koki, Furukawa,Miki, Shichishima-Nakamura,Akiko, Ohkawara,Hiroshi, Nollet,Kenneth E, Ohto,Hitoshi, Takeishi,Yasuchika
Format:	Digital revista
Language:	English
Published:	Sociedad de Biología de Chile 2015
Online Access:	http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602015000100041
Tags:	Add Tag No Tags, Be the first to tag this record!