Expansion of CD4+CD25+FoxP3+ regulatory T cells in hepatitis C virus‐related chronic hepatitis,cirrhosis and hepatocellular carcinoma

Aim: Regulatory T (Treg) cells may play a pivotal role in the persistence of hepatitis C virus (HCV) infection and the development of hepatocellular carcinoma (HCC). Therefore, we examined their frequency in peripheral blood from patients with HCV‐positive chronic hepatitis (CH), cirrhosis (LC) and HCC. Methods: Treg cells were identified as CD4⁺, CD25⁺ and FoxP3⁺ T lymphocytes using three‐color FACS. The frequency of Treg cells was expressed as a percentage of the total CD4⁺ T lymphocytes, and the phenotype of Treg cells was examined using CD45RA. Results: Treg cells were significantly increased in CH (5.88 ± 0.19%, n = 76; P < 0.01), LC (6.10 ± 0.28%, n = 40; P < 0.001) and HCC (6.80 ± 0.30%, n = 57; P < 0.0001) compared to healthy control (5.13 ± 0.25%, n = 31). However, Treg cells were not increased with the progression of fibrosis or the grade of inflammations. Treg cells were slightly increased in early‐stage HCC (6.91 ± 0.40%) compared with advanced‐stage HCC (6.58 ± 0.39%), but these results were not statistically significant. In a serial examination, a distinct increase in Treg cells after local therapy for early‐stage HCC was a hallmark of early recurrence. Most expanded Treg cells in HCC were CD45RA^‐, suggesting that a memory‐type Treg population had differentiated in the periphery and not in the thymus. Conclusion: We observed an increase in Treg cells in HCV‐related chronic liver disease, particularly in HCC, and these cells were shown to be memory‐type Treg cells.     

Ascaris suum infection modulates inflammation: Implication of CD4+ CD25high Foxp3+ T cells and IL‐10

Helminth infections have the ability to modulate host's immune response through mechanisms that allow the chronic persistence of the worms in the host. Here, we investigated the mechanisms involved on the suppressive effect of Ascaris suum infection using a murine experimental model of LPS‐induced inflammation. We found that infection with A. suum markedly inhibited leucocyte influx induced by LPS into air pouches, suppressed secretion of pro‐inflammatory cytokines (IL‐1β, TNF‐α and IL‐6) and induced high levels of IL‐10 and TGF‐β. Augmented frequency of CD4⁺ CD25^high Foxp3⁺ T cells was observed in the mesenteric lymph nodes of infected mice. Adoptive transfer of purified CD4⁺ CD25⁺ T cells to recipient uninfected mice demonstrated that these cells were able to induce a suppressive effect in the LPS‐induced inflammation in air pouch model. In addition, adoptive transfer of CD4⁺ CD25⁺ T cells derived from IL‐10 knockout mice suggests that this suppressive effect of A. suum infection involves IL‐10 cytokine. In conclusion, our results demonstrated that A. suum experimental infection was capable of suppressing LPS‐induced inflammation by mechanisms, which seem to be dependent on responses of CD4⁺ CD25⁺ T cells and secretion of IL‐10 cytokine.     

CCL17 and CCL22 chemokines within tumor microenvironment are related to infiltration of regulatory T cells in esophageal squamous cell carcinoma

It has been reported that an increased population of regulatory T cells (T‐regs) is one of the reasons for impaired anti‐tumor immunity. We investigated the frequency of Foxp3⁺ T‐regs in tumor‐infiltrating lymphocytes (TILs) and peripheral blood lymphocytes (PBLs) of patients with esophageal squamous cell carcinoma (ESCC). Furthermore, in order to elucidate the mechanisms behind T‐regs accumulation within tumors, we evaluated the relationship between CCL17 or CCL22 expression and the frequency of Foxp3⁺ T‐regs. CD4⁺CD25⁺Foxp3⁺ T‐regs as a percentage of CD4⁺ cells were counted by flow cytometry. The frequency of CCL17⁺ or CCL22⁺ cells among CD14⁺ cells in tumors was also evaluated by flow cytometry. Moreover, an in vitro migration assay using T‐regs derived from ESCC was performed in the presence of CCL17 or CCL22. The frequency of Foxp3⁺ T‐regs in TILs was significantly higher than that in the normal esophageal mucosa (24.6 ± 10.0 vs 7.1 ± 5.9%, P < 0.01). The frequency of Foxp3⁺ T‐regs in PBLs of ESCC patients was significantly higher than that in normal healthy donors (7.0 ± 4.2 vs 2.5 ± 1.0%, P < 0.01). Furthermore, the frequency of CCL17⁺ or CCL22⁺ cells among CD14⁺ cells within tumors was significantly higher than that of normal esophageal mucosa, and there was a significant correlation between the frequency of CCL17⁺ or CCL22⁺ cells and Foxp3⁺ T‐regs in TILs. In addition, the in vitro migration assay indicated that T‐regs were significantly induced to migrate by CCL17 or CCL22. In conclusion, CCL17 and CCL22 within the tumor are related to the increased population of Foxp3⁺ T‐regs in ESCC.     

The immunosuppressive effects of CD4+CD25+ regulatory T cells on dendritic cells in patients with chronic hepatitis B

The characteristics and functions of CD4⁺CD25⁺ regulatory T cells (Tregs) have been well defined in murine and human systems. However, the interaction or crosstalk between CD4⁺CD25⁺ Tregs and dendritic cells (DCs) remains controversial. In this study, the effects of chronic hepatitis B (CHB) CD4⁺CD25⁺ Tregs on the maturation and function of monocyte‐derived DCs were examined. The results showed that CD4⁺CD25⁺ render the DCs inefficient as antigen‐presenting cells (APCs) despite prestimulation with CD40 ligand. This effect was marginally reverted by applying neutralizing antibodies (Abs) to IL‐10 and TGF‐β. There were an increased IL‐10 and TGF‐β secretion and reduced expression of costimulatory molecules in DC. Thus, in addition to a direct suppressor effect on CD4⁺T cells, CD4⁺CD25⁺ may modulate the immune response through DCs in CHB patients.     

Rapamycin combined with donor immature dendritic cells promotes liver allograft survival in association with CD4(+) CD25(+) Foxp3(+) regulatory T cell expansion

Aim: To determine whether donor immature dendritic cells (imDCs) combined with a short postoperative course of rapamycin (Rapa) has the ability to expand the CD4⁺CD25⁺Foxp3⁺ regulatory T (Treg) cells and prolong liver allograft survival. Methods: Orthotopic liver transplantation (OLT) was performed from Lewis rats to Brown Norway recipients. Three days before transplantation, animals were injected intravenously with 2 × 10⁶ donor bone marrow‐derived imDCs. Recipient rats (the combined treated group) also received Rapa for 7 d after liver transplantation. Additional groups received either imDCs alone, Rapa alone, or saline alone. Every six recipients from each group were killed at 14 days, 28 days after OLT. The changes of CD4⁺CD25⁺Foxp3⁺ Treg cells in peripheral blood and spleen, histological changes of liver grafts, and serum cytokine levels were investigated. The other six recipients were left in each group to observe the animal survival. Results: Donor imDCs followed by a short postoperative course of Rapa induced long‐term allograft survival. The percentage of CD4⁺CD25⁺Foxp3⁺ Treg cells in CD4⁺ T cells in the combination treatment group were significantly higher compared with the acute rejection group. Moreover, within the CD4⁺CD25⁺ T cell population the combination treatment recipients maintained a higher incidence of Foxp3⁺ T cells compared with the other groups. Despite the lower serum levels of interleukin (IL)‐2, IL‐12, and interferon‐γ in the combined treated group, the cytokine levels in the combined treated group at 7 days after OLT was nearly twice that at 3 days after OLT but decreased significantly compared with the other groups at 28 days after OLT. Serum IL‐10 level in the combined treated group was higher than the other groups. Conclusions: A single imDC infusion followed by a short postoperative course of Rapa prolongs liver allograft survival and enhances the expansion of Treg cells. This optimal protocol may be a promising administration protocol for the peritransplant tolerance induction.     

Increased PD‐1 and decreased CD28 expression in chronic hepatitis B patients with advanced hepatocellular carcinoma

Background/aims: Hepatitis B infection is a well‐known cause of hepatocellular carcinoma (HCC). This study aims to investigate the role that the co‐stimulatory molecule CD28 and co‐inhibitory molecule programmed death‐1 (PD‐1) play in compromising the function of tumour‐infiltrating lymphocytes (TIL) in hepatitis B virus (HBV)‐related HCC. Methods: A total of 45 patients with HBV‐related HCC were enrolled during the period February 2008 to March 2010. The immune phenotype and the expression of PD‐1, CD28 and CD127 in TIL in biopsy specimens and in peripheral blood lymphocytes (PBL) from the same patients were analysed by flow cytometry. Results: Among the 45 patients, there was a male predominance (80%) and the mean age was 50 ± 13.68 years (range: 29–71). The majority of TIL were CD45RO⁺CD69⁺. PD‐1 expression was higher and CD28 and CD127 expression levels were lower in TIL than in PBL. The prevalence of portal vein thrombosis was 40%. Furthermore, tumour thrombosis invasion into the portal vein correlated with the expression level of the PD‐1 co‐inhibitory molecule. Conclusion: PD‐1⁺ tumour‐infiltrating lymphocytes correlate with portal vein thrombosis and might serve as a potential prognostic marker of and a novel therapeutic target for HBV‐related HCC.     

Recruitment of Mycobacterium tuberculosis specific CD4+ T cells to the site of infection for diagnosis of active tuberculosis

Context. Accurate and early diagnosis of active tuberculosis (TB) is problematic as current diagnostic methods show low sensitivity (acid‐fast bacilli smears), are time‐consuming (culture of biological samples) or show variable results [Mycobacterium tuberculosis (MTB)‐specific PCR]. Objectives. In the course of infection, MTB‐specific T cells clonally expand at the site of infection and may thus be used as diagnostic marker for active disease. Design. In this cohort study, the frequency of MTB‐specific, interferon (IFN)‐γ expressing CD4⁺ T cells obtained from peripheral blood and the site of disease in 25 patients with suspected TB was assessed (n = 11, bronchoalveolar lavage; n = 7, pleural fluid; n = 1, ascites; n = 1, joint fluid; n = 5, cerebrospinal fluid). Results. Amongst 15 patients who showed proven active TB infection, a striking increase of MTB‐specific T cells was detected at the site of infection compared with peripheral blood (median increase: 28.5‐fold, range: 7.25–531 fold; median of IFN‐γ‐producing CD4⁺ T cells from blood: 0.02%, range: 0–0.52%; median of IFN‐γ‐producing CD4⁺ T cells from the site of infection: 1.81%, range: 0.29–6.55%, P < 0.001). Main outcome measure. Recruitment of MTB‐specific T cells to the site of infection yielded a sensitivity of 100% and specificity of 90%, irrespective of the compartment affected. Conclusions. The accumulation of MTB‐specific T cells at the site of infection may prove as useful diagnostic marker for an accurate and rapid diagnosis of active TB.     

A prospective study of T‐ and B‐lymphocyte subpopulations,CD81 expression levels on B cells and regulatory CD4+CD25+CD127low/−FoxP3+ T cells in patients with chronic HCV infection during pegylated interferon‐alpha2a plus ribavirin treatment

Summary. Resolution of hepatitis C virus (HCV) infection requires a complex interplay between innate and adaptative immune responses. The role of lymphocyte subpopulations during combined antiviral treatment remains to be defined. This study was conducted to assess the effect of pegylated interferon‐alpha2a (pegIFN‐α2a) and ribavirin treatment on peripheral blood lymphocytes, mainly on CD81 expression on B cells and CD4⁺CD25⁺CD127^low/?FoxP3⁺ regulatory T cells (Tregs) in patients with chronic HCV infection. Thirty‐five patients with chronic HCV infection who started pegIFN‐α2a and ribavirin treatment were enrolled. Peripheral blood mononuclear cells (PBMC) were obtained at baseline before treatment (BT), mid‐treatment (MT), the end of treatment (ET) and 24 weeks post‐treatment (PT). During combined antiviral treatment, a significant decrease in the percentage of CD3⁺, CD8⁺, CD3⁺gamma/delta (γδ)⁺, CD19⁺ lymphocyte subpopulations and Tregs was observed. There was also a significant increase in the percentage of the CD4⁺ lymphocyte subpopulation and in CD81 expression levels on CD19⁺ B cells when BT was compared with ET (all P < 0.05). Seventeen patients were nonresponders (NR) and 18 had a sustained virological response (SVR). At baseline, NR patients had higher CD81 expression levels on CD19⁺ B cells (P = 0.017) and a higher Tregs percentage (P = 0.025) than SVR patients. Our results suggest that immunomodulation fluctuates during antiviral treatment and that percentage CD81 expression levels on B cells and Tregs might be useful as an immunological prognostic factor for pegIFN‐α2a and ribavirin treatment response in chronic HCV infection.     

Expression of interferon-g and interleukin-4 production in CD4+ T cells in patients with chronic heart failure

The prevalence of inflammation is high among patients with chronic heart failure (CHF). Reduced ejection fraction was associated with frequency of CD4⁺ T cells of leukocytes. Therefore, we investigated inflammatory cytokines of expression markers in CD4⁺ T cells in patients with CHF. Blood samples were obtained from 103 patients with CHF, from 83 patients with stable angina (SA), and from 57 controls. Interferon-γ (IFN-γ)-positive CD4⁺ T cells and interleukin-4 (IL-4)-positive CD4⁺ T cells were analyzed using 3-color flow cytometry. The frequency (%) of IFN-γ-positive CD4⁺ T cells increased in patients with CHF compared with those with SA and controls (CHF: 28.3 ± 13.8, SA: 23.50 ± 10.38, controls: 19.00 ± 7.45, P < 0.001). There was no significant difference in the frequency of IL-4-positive CD4⁺ T cells among the three groups. The frequencies of CD4⁺ T cells that stained for IFN-γ decreased from 32.37% ± 16.40% on admission to 26.91% ± 12.53% after 2 weeks in 26 patients with CHF. B-type natriuretic peptide (pg/ml) and high-sensitivity C-reactive protein (mg/dl) levels decreased from 251.7 ± 150.4 and 0.64 ± 0.78 on admission to 208.2 ± 166.4 and 0.36 ± 0.34 after 2 weeks in the 26 patients with CHF. We have demonstrated expression of IFN-γ production of CD4⁺ T cells during CHF. Prevention of unwanted T cell activation could represent a new target in the treatment of CHF.     

Induction of regulatory T cells by Opisthorchis viverrini

Opisthorchis viverrini causes public health problems in South‐East Asia. Recently, TGF‐β and IL‐10 have been reported to increase in O. viverrini‐infected hamsters but the sources of these cytokines are still unknown. In this study, the CD4⁺ T cells in infected hamsters were investigated. It was demonstrated that IL‐4⁺CD4⁺ T cells were significantly increased in hamster spleens and mesenteric lymph nodes (MLNs) during chronic infection. Interestingly, IL‐10⁺CD4⁺ T cells were also discovered at a significant level while Treg (T regulatory)‐like TGF‐ β⁺CD4⁺ T cells were in MLNs of infected hamsters. Moreover, the CD4⁺CD25⁺Foxp3⁺ Treg cell response was significantly found both in spleens and MLNs in infected hamsters. The findings were then confirmed by development of T‐cell clones against crude somatic antigens (CSAg) in immunized BALB/c mice. Five clones named TCC21, TCC23, TCC35, TCC41 and TCC108 were established. The TCC21 was found to be the TGF‐β⁺CD4⁺ while TCC35, TCC41 and TCC108 were IL‐4⁺CD4⁺ and TCC23 was IFN‐γ⁺CD4⁺. This TGF‐β⁺CD4⁺ T clone showed an inhibitory function in vitro in mononuclear cell proliferation via TGF‐β‐mediated mechanisms. This study indicated that O. viverrini‐infected hamsters could induce TGF‐β⁺ CD4⁺ Treg‐like cells. The CSAg‐specific Tregs secreted high TGF‐β, and limited immune cell proliferation.     

Plasma Exchange Downregulates Activated Monocytes and Restores Regulatory T Cells in Kawasaki Disease

In Kawasaki disease (KD), the effect of plasma exchange (PE) on immune cells has not been fully elucidated. Therefore, we examined the changes in the number of CD14⁺ CD16⁺ activated monocytes, regulatory T (T_reg), and T‐helper type 17 (Th17) cells in KD patients treated with PE. The percentage of total monocytes and subclasses of lymphocytes, including CD4⁺ and CD8⁺ T cells, and CD19⁺ B cells, showed no significant difference before and after PE. However, the percentage of CD14⁺ CD16⁺ monocytes in total leukocytes decreased significantly after PE (1.1% ± 1.5% vs. 2.1% ± 2.3%, P < 0.05). Furthermore, while the percentage of Th17 cells in CD4⁺ T cells did not change, the percentage of T_reg cells in CD4⁺ T cells increased significantly after PE (11.1% ± 5.1% vs. 8.0% ± 4.4%, P < 0.05). Therefore, PE downregulates activated monocytes and upregulates T_reg cells toward normal levels and thus attenuates inflammation in KD.     

Association of circulating regulatory T cell number with the incidence and prognosis of diffuse large B‐cell lymphoma

Regulatory T (Treg) cells are essential for maintaining immune tolerance. High Treg frequencies have been reported in peripheral blood and tissue samples of patients with solid tumors while their role in lymphomas, including diffuse large B‐cell lymphoma (DLBCL) has not been clearly established. In this study, we analyzed the circulating Treg numbers in 27 patients with newly diagnosed DLBCL and 17 healthy individuals. Tregs were detected by flow cytometry based on CD4⁺CD25^highFoxP3⁺ phenotype. In addition, the expression of CD45RA, HLA‐DR, CD62L, CD39, and CTLA4 was analyzed. The number of circulating Treg cells was lower in patients with DLBCL than in healthy controls: median 23 (range, 4–107)/μL vs. 41 (19–104)/μL (P = 0.04). In particular, the number of Tregs expressing CD45RA (naïve Tregs), HLA‐DR (marker of activation), and CD62L (L‐selectin) was decreased in the DLBCL group. Lower (below median) number of circulating Tregs was associated with reduced chance of achieving complete remission (29% vs. 69%, P = 0.05) and reduced probability of even‐free survival (24% vs. 84% at 1 yr, P = 0.0004), independently on the International Prognostic Index. We conclude that low number of circulating Tregs may be associated with poor prognosis in patients with DLBCL. However, our observations require confirmation in larger patient population.     

The Decreased CD4+CD25+ FoxP3+ T Cells in Nonstimulated Allergic Rhinitis Patients Sensitized to House Dust Mites

Objective. Regulatory (CD4⁺CD25⁺) T cells have been shown to play an important role in the development of allergic diseases. This study aims to investigate CD4⁺CD25⁺ T cells, Forkhead box P3 (FoxP3⁺ cells), and T-helper 1/T-helper 2 (Th1/Th2) cytokines in newly diagnosed allergic rhinitis (AR) patients. Methods. Altogether, 10 subjects with AR and 12 age-matched nonallergic healthy subjects were included in this study. CD4⁺CD25⁺ T cells, FoxP3⁺ T cells in peripheral blood mononuclear cells (PBMCs) were evaluated by flow cytometry, and the Th1/Th2 cytokine levels were determined by cytometric bead array immunoassay in both PBMC supernatants and nasal lavage fluids. Results. The percentage of CD4⁺CD25⁺ T cells were significantly higher, whereas the percentage of FoxP3⁺ cells were lower in AR patients compared with healthy subjects. In PBMC culture supernatants, interleukin-10 (IL-10) levels were significantly lower (p = .012), whereas IL-4, IL-5, and tumor necrosis factor-α (TNF-α) levels in nasal lavage fluids were higher in AR patients compared with healthy subjects (p = .026, p = .015, p = .03, respectively). Conclusions. Our findings indicate that decrease in CD4⁺CD25⁺FoxP3⁺ T cell fraction and diminished levels of IL-10 are noteworthy without allergen stimulation in house dust mite AR patients.     

The effect of Echinococcus granulosus on spleen cells and TGF‐β expression in the peripheral blood of BALB/c mice

Cystic echinococcosis (CE) caused by the cestode Echinococcus granulosus (E. granulosus) is a zoonotic parasitic disease. The effective immune evasion mechanisms of E. granulosus allow it to parasitize its hosts. However, the status of the innate and adaptive immune cells and their contributions to E. granulosus progression remain poorly understood. In this study, we aimed to determine the impact of E. granulosus infection on T cells, NK cell responses and TGF‐β expression during the early infection phase in BALB/c mice. In E. granulosus infections, there was an increasing tendency in the percentage of CD4⁺CD25⁺ T cells and CD4⁺Foxp3⁺ T cells and peripheral blood TGF‐β levels and relative expression of the Foxp3 gene. Moreover, there were a decreasing tendency in the percentage of NK cells and NK cell cytotoxicity and the expression of NKG2D on NK cells. The TGF‐β1/Smad pathway was activated by E. granulosus in mice. Above results can be reversed by the inhibitor SB‐525334 (potent activin receptor‐like kinase 5 inhibitor). These results suggest that the TGF‐β/Smad pathway plays an important role in changes of T‐cell or NK cell responses. These results may contribute to revealing the preliminary molecular mechanisms in establishing hydatid infection.     

CCL22 is involved in the recruitment of CD4+CD25high T cells into tuberculous pleural effusions

Background and Objective: CD4⁺CD25^high regulatory T cells are increased in tuberculous pleural effusions (TPE). However, the mechanism by which CD4⁺CD25^high T cells infiltrate into the pleural cavity is unknown. The aim of this study was to investigate whether the chemokines CCL22 and CCL17 are present in TPE, and the chemoattractant activity of these chemokines for infiltration of CD4⁺CD25^high T cells into the pleural space. Methods: The concentrations of CCL22 and CCL17 were measured in pleural effusions from 33 patients with tuberculous pleurisy, 21 patients with pleural bacterial infections and 18 patients with transudative pleural effusions. T lymphocyte subsets in pleural effusions were assessed by flow cytometry. Pleural effusion cells were analysed for the expression of CCL22. The chemoattractant activity of CCL22 for CD4⁺CD25^high T cells was assessed in vitro. Results: The frequency of CD4⁺CD25^high T cells was significantly higher in TPE than in blood. High concentrations of CCL22 were detected in tuberculous effusions, but not in bacterial effusions or transudates. Macrophages and T cells in TPE expressed CCL22. Tuberculous pleural fluid was chemotactic for CD4⁺CD25^high T cells in vitro, and anti‐CCL22 antibody partly inhibited this chemotactic activity. Conclusions: CCL22 appeared to be increased in TPE compared with bacterial pleural effusions or transudates. CCL22 may be responsible for the infiltration of CD4⁺CD25^high T cells into the pleural space of patients with tuberculous pleurisy.     

Heligmosomoides bakeri antigen rescues CD4-positive T cells from glucocorticoid-induced apoptosis by Bcl-2 protein expression

Heligmosomoides bakeri infection in mice is associated with a dominant CD4⁺ T‐cell response and with the activity of natural Treg cells with CD4⁺CD25⁺ phenotype. The polarization of Th2 T‐cell phenotype and the increase in the CD4⁺CD25⁺ T cell population are regulated by glucocorticoids that induce apoptosis in CD4⁺CD25^? T cells and inhibit apoptosis in CD4⁺CD25⁺ T cells. However, exposure of mice to H. bakeri antigen induces a high glucocorticoid concentration in serum and a reduction in the number of CD4‐positive; CD4⁺CD25^? and CD4⁺CD25⁺ apoptotic T cells in mesenteric lymph node cells. In this study to evaluate the in vitro effect of the anti‐apoptotic property of H. bakeri antigen on T cells, apoptosis of these cells was induced by glucocorticoids‐dexamethasone (Dex). Excretory–secretory (ES) antigen of the nematode prevented Dex‐induced apoptosis in CD4‐positive T cells with CD4⁺CD25^? and CD4⁺CD25^High phenotype by Bcl‐2 protein expression. Contrary to the effect on CD4‐positive T cells, survival of CD8⁺ T cells was not connected with expression of Bcl‐2 protein. This suggest that H. bakeri antigen modulates CD4‐positive T cell sensitivity to glucocorticoid‐induced apoptosis by induction of Bcl‐2 protein.     

肝细胞癌患者肝脏组织中CD4+CD25+调节性T淋巴细胞的表达及意义

目的探讨CD4^＋CD25^＋调节性T淋巴细胞在肝细胞癌患者肝脏组织中的表达及意义。方法利用流式细胞仪对31例肝细胞癌患者肝脏组织及末梢静脉血、15份正常肝脏组织、48名正常人末梢静脉血中的CD4^＋CD25^＋调节性T淋巴细胞、CD8^＋T淋巴细胞进行定量及量化关系分析,同时对肝脏组织中CD4^＋CD25^＋调节性T淋巴细胞进行定位分析。结果肝组织CD4^＋CD25^＋调节性T淋巴细胞含量：肝细胞癌组肿瘤周围组织为10．8%±2．3%,远离肿瘤部位组织为4．6%±0．9%、15份正常人肝脏组织为6．0%±0．6%,肿瘤周围组织和远离肿瘤部位组织与正常对照组相比,t值分别为2．05和2．04,P值均＜0．05,差异有统计学意义。外周血中CD4^＋CD25^＋调节性T淋巴细胞含量：肝细胞癌组末梢静脉血中为9．4%±1．0%,正常对照组为12．9%±1．3%,t=13．05,P＜0．01,差异有统计学意义。在肿瘤周围随着CD4^＋CD25^＋调节性T淋巴细胞的增加,CD8^＋T淋巴细胞出现了减少的趋势。结论CD4^＋CD25^＋调节性T淋巴细胞通过对CD8^＋T淋巴细胞的抑制参与肝癌细胞抗肿瘤免疫的作用。