Abstract
Background
The purpose of this study was to investigate the presence of CD4^+^CD25^+^FOXP3^+^ regulatory T (Treg) cells both in peripheral blood and local tumors in patients with nasal inverted papilloma (NIP).
Methods
By using flow cytometry, the frequencies of CD4^+^CD25^+^FOXP3^+^ Treg cells in both peripheral blood and tissues from 18 patients with NIP and 8 control subjects were determined. CCL22 and CCL17 proteins in NIP tumors were analyzed by using enzyme‐linked immunosorbent assay. The suppressive capacity of Treg cells was estimated by WST‐8 and enzyme‐linked immunosorbent assay (ELISA; interferon‐gamma [IFN‐γ] and interleukin‐4 [IL‐4]) analysis.
Results
Patients with NIP showed increased CD4^+^CD25^+^FOXP3^+^ Treg cell frequencies in tumor tissues and CD4^+^ T cell fraction rather than in peripheral blood. CCL22 increased in NIP tumors. Phytohemagglutinin (PHA)‐induced proliferation and cytokine production of CD4^+^CD25^‐^ T cells were suppressed equally well by CD4^+^CD25^high^ cells from both patients with NIP and controls.
Conclusion
Our study demonstrated the increased frequencies of CD4^+^CD25^+^FOXP3^+^ Treg cells in NIP tumors, which might be influenced by CCL22. © 2010 Wiley Periodicals, Inc. Head Neck, 2011