Abstract
CD62L is the human homologue of the murine lymphocyte homing receptor, mel-14. We investigated CD62L+ cells in the spleen from patients with gastric cancer. Flow cytometric analysis revealed that CD62L+ cells were decreased in the peripheral blood, but inversely increased in the spleen in parallel with disease progression in gastric cancer patients. The increased CD62L+ cells resided in the CD4+ suppressor-inducer phenotype, and the removal of CD62L+ cells from spleen cells resulted in a decrease of concanavalin-A-induced suppressor activity in vitro in one-way allogeneic mixed lymphocyte reaction. The CD62L+ cells included CD4+CD25+ regulatory T cells. The culture supernatant of CD62L+ cells showed TGF-beta activity that permitted anchorage-independent growth of normal rat kidney (NRK) cells in a soft agar. TGF-beta activity was more significantly detectable in the splenic vein than in the peripheral blood, and TGF-beta mRNA was detectable in the spleen from advanced gastric cancer patients. These results suggest that CD62L+ cells migrate into the spleen with disease progression of gastric cancer and serve as suppressor-inducer cells with TGF-beta production to induce regulatory T cells, contributing to disease-associated immunosuppression in advanced gastric cancer patients.
Footnotes
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Abbreviations: CD, cluster differentiation; EDTA, ethylene-diaminetetraacetic acid; EGF, epidermal growth factor; RPMI, Roswel Park Memorial Institute; RT-PCR, reverse transcription polymerase chain reaction; TGF, transforming growth factor.
- Received September 10, 2004.
- Accepted December 29, 2004.
- Copyright© 2005 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved
