Comparative Study of Regulatory T Cell Function of Human CD25+CD4+ T Cells from Thymocytes, Cord Blood, and Adult Peripheral Blood

• Published in: Journal of immunology research 2008, Vol.2008 (2008), p.1-12
• Main Authors: Morimoto, Chikao, Uchiyama, Takehiko, Yoshida, Satoko, Kurosawa, Hiromi, Nagatsu, Masayoshi, Ohnuma, Kei, Takahashi, Nozomu, Fujimaki, Wakae, Dang, Nam H.
• Format: Article
• Language: English
• ISSN: 2314-8861; 2314-7156
• DOI: 10.1155/2008/305859

CD25+CD4+ regulatory T cells suppress T cell activation and regulate multiple immune reactions in in vitro and in vivo studies. To define the regulatory function of human CD25+CD4+ T cells at various stages of maturity, we investigated in detail the functional differences of CD25+CD4+ T cells from thymocytes, cord blood (CB), and adult peripheral blood (APB). CB CD25+CD4+ T cells displayed low-FOXP3 protein expression level and had no suppressive activity. In contrast, CD25+CD4+ T cells from thymocytes or APB expressed high expression level of FOXP3 protein associated with significant suppressive activity. Although CB CD25+CD4+ T cells exhibited no suppressive activity, striking suppressive activity was observed following expansion in culture associated with increased FOXP3 expression and a shift from the CD45RA+ to the CD45RA− phenotype. These functional differences in CD25+CD4+ T cells from Thy, CB, and APB hence suggest a pathway of maturation for Treg in the peripheral immune system.