CD4^+CD25^(high) Regulatory Cells in Peripheral Blood of NSCLC Patients

The proportion and changes of CD4^＋CD25^high regulatory T cells （Trs） in peripheral blood of non-small cell lung cancer （NSCLC） patients were analyzed and their clinical significance explored. The peripheral blood was collected from 61 patients with NSCLC and 15 healthy controls. By using monoclonal antibodies, the blood samples were evaluated with the flow cytometry for lymphocyte subsets （CD3^＋, CD4^＋ and CD8^＋） and CD4^＋CD25^high Tr cells. The results showed that the proportion of CD4^＋CD25^high Tr cells in NSCLC group was significantly higher than in control group [（4.36 ±2.07） % vs （2.04±1.03） %, P〈0.01]. The proportion of CD4^＋CD25^ high Tr cells in late stage was higher than that in early stage [stages Ⅰ ＋Ⅱ （2.264±0.6） %; stage Ⅲ（3.284± 1.38） %; stage IV （6.06 4±4.08） %] （P〈0.05）. Kaplan-Meier survival analysis revealed that the prognosis of the patients who had higher proportion of CD4^＋CD25^high Tr cells in peripheral blood was worse （P=0.0026）. In conclusion, the relative increase in CD4^＋CD25^high Tr cells in peripheral blood may be related to im- munosuppression and tumor progression in patients with NSCLC. This finding suggests that CD4^＋CD25^high Tr cells in peripheral blood of NSCLC may be positive for prognosis analysis. The use of depletion of the CD4^＋CD25^high Tr cell therapy to treat NSCLC patients may be an effective strategy.

INVESTIGATION OF REGULATORY T CELLS IN PATIENTS WITH NON-SMALL CELL LUNG CANCER

Objective To evaluate the prevalence of CD4 ^＋ CD25^high regulatory T cells （ Treg cells） in the peripheral blood mononuclear cells （PBMC） and tumor-infiltrating lymphocytes （TIL） of patients with non-small cell lung cancer （NSCLC） and to investigate immunosuppression to the progression of cancer. Methods Peripheral blood and tumor tissues were collected from 20 patients with NSCLC at the time of surgery. None of the patients received surgery, radiotherapy, chemotherapy, or other medical interventions before this study. Cancer stages of the patients were Ⅰ-Ⅲ A. Venous blood samples were obtained from 20 health donors. PBMC were isolated from blood samples by differential centrifugation over Ficoll-Hypaque. TILs were isolated from tumors by differential centrifugation over Ficoll-Hypaque and Percoll. Percentage of CD4^＋ CD25^highTr/CD4＋T in PBMC and TIL was assessed by the flow cytometry. Results The percentage of CD4^ ＋ CD25high Tr/ CD4 ^＋T in PBMC [ （4. 87 ± 1.22 ） % ] of NSCLC patients was significantly higher than that in healthy donors [ （ 2.36 ± 0. 72 ） % ] （ P 〈 0.01 ）. The percentage of CD4^＋ CD25^highTr/ CD4^＋ T in PBMC [ （5.40 ± 1.20） % ] of NSCLC patients in stage Ⅱ-Ⅲ A was significantly higher than that in stage Ⅰ [ （3. 87 ± 0. 22 ） % ] （ P 〈 0. 01 ）. The percentage of CD4 ＋ CD25hiShTr/ CD4 ＋ T in TIL[ （ 8. 66 ±0. 76） % ] of NSCLC patients in stage Ⅱ-Ⅲ A was significantly higher than that in stage Ⅰ [ （ 7. 04 ± 0. 80） % ] （ P 〈 0. 01 ）. Conclusion The prevalence of CD4 ^＋ CD25^highTreg cells in PBMC and TIL of NSCLC patients was significantly higher than that in healthy donors. These Treg cells may be preventing appropriate antitumor immune responses. The population of CD4^ ＋ CD25^highTreg cells in PBMC and TILs of NSCLC patients with Ⅱ-Ⅲ A stage was significantly higher than that of NSCLC patients with Ⅰ stage. These Treg cells may facilitate development of tumors.