Expression of interleukin (IL)-2 and IL-7 receptors discriminates between human regulatory and activated T cells.
Abnormalities in CD4(+)CD25(+)Foxp3(+) regulatory T (T reg) cells have been implicated in susceptibility to allergic, autoimmune, and immunoinflammatory conditions. However, phenotypic and functional assessment of human T reg cells has been hampered by difficulty in distinguishing between CD25-expressing activated and regulatory T cells. Here, we show that expression of CD127, the alpha chain of the interleukin-7 receptor, allows an unambiguous flow cytometry-based distinction to be made between CD127(lo) T reg cells and CD127(hi) conventional T cells within the CD25(+)CD45RO(+)RA(-) effector/memory and CD45RA(+)RO(-) naive compartments in peripheral blood and lymph node. In healthy volunteers, peripheral blood CD25(+)CD127(lo) cells comprised 6.35 +/- 0.26% of CD4(+) T cells, of which 2.05 +/- 0.14% expressed the naive subset marker CD45RA. Expression of FoxP3 protein and the CD127(lo) phenotype were highly correlated within the CD4(+)CD25(+) population. Moreover, both effector/memory and naive CD25(+)CD127(lo) cells manifested suppressive activity in vitro, whereas CD25(+)CD127(hi) cells did not. Cell surface expression of CD127 therefore allows accurate estimation of T reg cell numbers and isolation of pure populations for in vitro studies and should contribute to our understanding of regulatory abnormalities in immunopathic diseases.
Seddiki
Nabila
N
Centenary Institute of Cancer Medicine and Cell Biology, Faculty of Medicine, University of Sydney, Newtown, NSW 2042, Australia.
Santner-Nanan
Brigitte
B
Martinson
Jeff
J
Zaunders
John
J
Sasson
Sarah
S
Landay
Alan
A
Solomon
Michael
M
Selby
Warwick
W
Alexander
Stephen I
SI
Nanan
Ralph
R
Kelleher
Anthony
A
Fazekas de St Groth
Barbara
B
D000328:Adult; D006801:Humans; D007231:Infant, Newborn; D008213:Lymphocyte Activation / Q000276:immunology*; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis* / Q000235:genetics; D020395:Receptors, Interleukin-7 / Q000096:biosynthesis* / Q000235:genetics; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000378:metabolism*
D015375:Receptors, Interleukin-2; D020395:Receptors, Interleukin-7