[Phenotypical and functional characteristic of FoxP3(+);CD39(+); regulatory T cells in humans].

AIM: To investigate phenotypical and functional characteristics of the CD39(+);FoxP3(+);regulatory T (Treg) cells in humans.

METHODS: We collected peripheral blood from 10 healthy volunteers and separated PBMC by using density gradient centrifugation, and then detected the expression of CTLA-4, HLA-DR, CD45RO and Ki-67 on CD39(+);FoxP3(+); and CD39(-);FoxP3(+);Treg cells by using flow cytometric analysis. [(3);H]-thymidine incorporation assay and ELISA were used to monitor the suppressive capacity of CD39(+); FoxP3(+); Treg cells on proliferation and IFN-gamma secretion of Treg-depleted PBMC.

RESULTS: The expression of CTLA-4, HLA-DR, CD45RO and Ki-67 was significantly higher in CD39(+);FoxP3(+); Treg cells than those in CD39(-);FoxP3(+); Treg cells. The suppressive capacity of CD39(+);FoxP3(+); Treg cells on proliferation and IFN-gamma secretion of Treg-depleted PBMC was significantly higher than those of FoxP3(+);CD39(-);Treg cells.

CONCLUSION: CD39(+);Fxop3(+);Treg subset may play an essential role in immune regulation of Treg, and CD39 can be used as a surface marker to identify the functional Treg cells.