Human T cells express CD25 and Foxp3 upon activation and exhibit effector/memory phenotypes without any regulatory/suppressor function

Authors

Maciej Kmieciak, Virginia Commonwealth UniversityFollow
Madhu Gowda, Virginia Commonwealth UniversityFollow
Laura Graham, Virginia Commonwealth UniversityFollow
Kamar Godder, Virginia Commonwealth University
Harry D. Bear, Virginia Commonwealth UniversityFollow
Francesco M. Marincola, National Institutes of Health
Masoud H. Manjili, Virginia Commonwealth UniversityFollow

Document Type

Article

Original Publication Date

2009

Journal/Book/Conference Title

Journal of Translational Medicine

Volume

2009

DOI

10.1186/1479-5876-7-89

Comments

Originally published at http://dx.doi.org/10.1186/1479-5876-7-89

Date of Submission

September 2014

Abstract

Background Foxp3 has been suggested to be a standard marker for murine Tregs whereas its role as marker for human Tregs is controversial. While some reports have shown that human Foxp3+ T cells had no regulatory function others have shown their role in the inhibition of T cell proliferation.

Methods T cell activation was performed by means of brayostatin-1/ionomycin (B/I), mixed lymphocyte reaction (MLR), and CD3/CD28 activation. T cell proliferation was performed using BrdU and CFSE staining. Flow cytometry was performed to determine Foxp3 expression, cell proliferation, viabilities and phenotype analyses of T cells.

Results Both CD4+ and CD8+ T cells expressed Foxp3 upon activation in vitro. Expression of Foxp3 remained more stable in CD4+CD25+ T cells compared to that in CD8+CD25+ T cells. The CD4+CD25+Foxp3+ T cells expressed CD44 and CD62L, showing their effector and memory phenotypes. Both FoxP3- responder T cells and CD4+FoxP3+ T cells underwent proliferation upon CD3/CD28 activation.

Conclusion Expression of Foxp3 does not necessarily convey regulatory function in human CD4+CD25+ T cells. Increased FoxP3 on CD44+ effector and CD44+CD62L+ memory T cells upon stimulation suggest the activation-induced regulation of FoxP3 expression.

Rights

© 2009 Kmieciak et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Is Part Of

VCU Microbiology and Immunology Publications