Effector, memory and naïve CD8+ T cells in peripheral blood and pleural effusion from lung adenocarcinoma patients

The proportions of na?ve, memory and effector CD8+ T cells in peripheral blood and pleural effusion from lung adenocarcinoma patients were studied. CD8+ T subsets were identified by using a combination of the following antibodies: anti-CD45RA, anti-CD45RO, anti-CD27 and anti-CD28, as well as antibodies to other markers. Fas-positive cells were determined in each CD8+ T subset. Also, the intracellular cytokine patterns of CD4+ and CD8+ lymphocytes from pleural effusion were analysed. In na?ve, memory and effector CD8+ T subsets no significant differences were observed in peripheral blood between healthy donors and cancer patients. In contrast, a high proportion of cells with memory phenotype (CD45RA-CD45RO+CD27+CD28+) and a low proportion of cells with effector phenotype (CD45RA+CD45RO-CD27-CD28-) were found in pleural effusion with respect to peripheral blood (P<0.001). The altered proportions of CD8+ T subsets in pleural effusion were not mediated by type 2 cytokines produced by CD4+ or CD8+ lymphocytes. In the effector CD8+ T subset, from peripheral blood as well as from pleural effusion, a low percentage of perforin-expressing cells was observed compared to granzyme A-expressing cells. Additionally, a high percentage of na?ve CD8+ T cells expressing Fas was found. Our data suggest that: (i) terminal-differentiation process of CD8+ T cells is blocked, and (ii) early Fas-expression in CD8+ T cells, which was reflected even in peripheral blood, may lead to apoptosis of na?ve cells when they reach the effector stage. All these processes may contribute to the inadequate antitumour immune response found in lung carcinoma patients.     

CCR6 regulates the function of alloreactive and regulatory CD4+ T cells during acute graft-versus-host disease

The chemokine receptor CCR6 is expressed by CD4+ T cell effector/memory and regulatory effector/memory (TREM) subsets. Here we show that CCR6 modulates graft-versus-host-disease (GVHD) responses in both alloreactive CD4+ T effector cells and regulatory T (Treg) cells. Mortality and morbidity due to acute GVHD were drastically reduced and delayed when na?ve T cells were derived from CCR6-deficient donor mice. This deficiency also affected the suppressive ability of Treg cells in GVHD. CCR6-/- Treg cells were able to suppress T cell proliferation in vitro, but their in vivo capacity to downregulate target tissue damage induced by na?ve wild type (WT) T cells was impaired. The data demonstrate a requirement for CCR6 in CD4+ T cell function in GVHD, in both effector and regulatory cell subsets.     

Characterization of effusion-infiltrating T cells: benign versus malignant effusions.

PURPOSE: While na?ve T cells circulate between peripheral blood and lymph nodes, memory effector T cells acquire certain surface molecules that enable them to travel to peripheral tissues and exert their effector function. We analyzed whether deficient numbers of effector-type T cells within the malignant effusion might contribute to tumor escape from immunosurveillance. EXPERIMENTAL DESIGN: We analyzed the expression of a broad range of adhesion molecules and chemokine receptors (CD62L, CD56, CCR4, CCR5, CCR7, CXCR3, CLA, and integrin alpha 4 beta 7) on tumor-associated lymphocytes in effusions and peripheral blood lymphocytes of patients with malignant ascites (n = 11) or malignant pleural effusion (n = 16). A tumor-associated lymphocyte:peripheral blood lymphocyte ratio was calculated as an indicator for homing of lymphocytes into the effusions and was compared with patients with nonmalignant ascites (n = 17). RESULTS: Patients with malignancies show an increased enrichment of T cells expressing the phenotype of "na?ve" (CD62L+ and CD45RA+CCR7+), "central memory" (CD45RA-CCR7+), and type 2-polarized (CCR4+) T cells within their effusions. In contrast, enrichment of "effector"-type (CD45RA-CCR7- or CD45RA+CCR7-) and presumably type 1-polarized T cells (CCR5+) at the tumor site is deficient. The same is true for natural killer cells and potentially cytotoxic CD56+ T cells. CONCLUSIONS: Here we show for the first time that patients with malignant effusions show a deficient enrichment of T cells expressing the phenotype of type-1-polarized effector T cells at the tumor site. This mechanism is likely to contribute to the escape of tumor cells from immunosurveillance.     

The receptor for hyaluronic acid-mediated motility induces specific CD8+ T cell response in healthy donors and patients with chronic myeloid leukemia after allogeneic stem cell transplantation

Recently, we described the receptor for hyaluronic acid-mediated motility (RHAMM) as a leukemia-associated antigen and characterized the RHAMM-derived peptide R3 (pos. 165-173: ILSLELMKL) as a CD8+ T cell epitope. Directing CD8+ T lymphocytes specifically to R3 might help to shape the graft-versus-leukemia effect observed after allogeneic stem cell transplantation (allo-SCT). To detect the potential induction of R3-specific cytotoxic T lymphocytes in chronic myeloid leukemia (CML) patients after allo-SCT and healthy donors, we used mixed lymphocyte peptide culture, enzyme-linked immunospot (ELISPOT) release assays for interferon (IFN)-gamma and granzyme B, tetramer staining and 51Cr release cytotoxicity assays. The R3 peptide showed the capacity to elicit specific CD8+ T cell responses characterized by the release of IFN-gamma and granzyme B upon stimulation with R3-pulsed T2 cells. Responses to R3 peptide were detected in 67% (6/9) of the CML patients after allo-SCT and 24% (8/34) of healthy donors in ELISPOT assays for IFN-gamma and granzyme B. These R3-specific CD8+ T cells comprised predominantly effector cells (CCR7-CD45RA+ or CD27-CD45RA+) in patients with CML after allo-SCT or healthy donors respectively. Cytotoxicity assays demonstrated effective lysis of CML progenitor cells by R3-primed CD8+ T lymphocytes. Imatinib inhibited the functional activation of R3-specific CD8+ T lymphocytes. In summary, we demonstrated R3-specific CD8+ effector T lymphocytes after allo-SCT in CML patients which might have been augumented by R3 peptide vaccination and hampered at least partially by imatinib in this particular patient cohort.     

Tumor-induced changes in the phenotype of blood-derived and tumor-associated T cells of early stage breast cancer patients

Tumor‐induced immune suppression has mainly been studied in patients with advanced cancer. Despite the fact that they are most likely to benefit from immunotherapy, patients with early stage cancers were under‐represented in these studies. We analyzed blood and tumor‐derived T cells from patients with stage 1 (n = 20), stage 2 (n = 23) or stage 3 (n = 1) breast cancer and found that, even early stage tumors induced T cell differentiation. Breast cancer patients had significantly more circulating CD8+ memory and fewer CD8+ naïve T cells than healthy controls (n = 10). Up‐regulation of CD69 and PD1 on cancer patient T cells suggests previous activation, and increased expression of the chemokine receptors CCR5 and CXCR3 on CD8+ T cells indicates that their homing capacity differs from that of healthy individuals. Comparison of blood‐derived and tumor‐associated T cells from patients with different metastatic status and tumor grades revealed that tumor progression and aggressiveness seem to favor the expansion of memory T cells over naive T cells. We have previously shown that immunosuppression in this patient population is stronger in the tumor than in the blood. Here, we report signs of exhaustion, such as loss of CD28, on tumor‐associated as compared to blood‐derived CD8+ T cells, despite the fact that tumor‐associated T cells are predominantly effector memory cells and express high levels of CD69. The finding that the presence of a tumor potentially induces immunosenescence early during tumorigenesis indicates that efficient immunotherapy might be difficult even in patients with early stage cancer due to T cell exhaustion and tolerance.     

Good syndrome presenting with CD8+ T-Cell large granular lymphocyte leukemia

Good Syndrome is an adult-onset combined immunodeficiency defined by hypogammaglobulinemia, low or absent number of B cells, T cell deficiency and thymic tumor. We have characterized CD8+ T cells from a patient with Good syndrome that presented with CD8+T-cell large granular lymphocytic leukemia (LGL). Characterization of peripheral blood CD8+ T cells revealed that majority of CD8+ T cells were terminally differentiated effector memory phenotype (T_EMRA; CD8+CCR7-CD45RA+), and were PD-1^high (CD279), ICOS^low (CD278), and granzyme^high. Almost all CD8+ T cells were IFN-γ+. CD8 Treg (CD8+CD183+CCR7+CD45RA-) were decreased. T_EMRA phenotype along with CD279^high, demonstrates that these are exhausted CD8+ T cells. This phenotype along with CD278^low may also explain severe T cell functional deficiency in our patient. In the present patient, T-LGL appears to be a clonal expansion of CD279+granzyme+IFN-γ+CD8+T_EMRA cells. To best of our knowledge this is the first case of CD8+T-cell LGL leukemia associated with Good syndrome.     

穿孔素和颗粒酶B在EBV相关噬血细胞综合征中的表达及临床意义

目的:动态观察EB病毒相关噬血细胞综合征(EBV-HLH)患儿外周血CD8+T细胞和NK细胞穿孔素和颗粒酶B的表达变化,探索其临床意义。方法:以传染性单核细胞增多症（IM）患儿60例、排除PRF1基因缺陷的EBV-HLH患儿30例及同期体检的健康儿童30例为研究对象,采用流式细胞术分析健康对照组、IM组以及EBV-HLH患儿治疗前后外周血中CD8+T细胞和NK细胞穿孔素和颗粒酶B的表达。结果:EBV-HLH、IM患儿CD8+T细胞的穿孔素和颗粒酶B的表达水平均高于健康对照组(P＜0.05),以IM患儿表达水平最高(P＜0.05),IM患儿NK细胞穿孔素和颗粒酶B的水平高于EBV-HLH和健康对照组(P＜0.05)。与治疗前比,治疗后存活的20例EBV-HLH患儿CD8+T细胞中穿孔素和颗粒酶B的表达下降(P＜0.05),而NK细胞中穿孔素和颗粒酶B水平升高(P＜0.05)。结论:EBV-HLH患儿体内CD8+T/NK细胞中穿孔素和颗粒酶B存在差异性表达,NK细胞穿孔素和颗粒酶B的高表达有利于疾病的恢复。     

CD4+CD25+CCR6+调节性T细胞在小鼠乳腺癌模型中对CD8+T细胞的抑制作用

目的：观察CD4+CD25+CCR6+调节性T细胞（简称CCR6+Tregs）体内对CD8+T细胞功能的抑制作用,并探讨其与肿瘤免疫逃逸的关系。方法：建立4T1乳腺癌细胞荷瘤裸鼠模型,FACS分选CCR6+Tregs,检测其Foxp3的表达;FACS分选4T1特异性CD8+T细胞,CFSE标记后分别与CCR6+Tregs或CCR6Tregs共同过继转输入4T1荷瘤裸鼠体内,观察荷瘤裸鼠肿瘤生长情况和小鼠存活时间;FACS检测肿瘤组织中CD8+T细胞的增殖、细胞因子IFNγ的产生和颗粒酶B的表达情况。结果：CCR6+Tregs和CCR6Tregs均高表达Foxp3;CCR6+Tregs和CD8+T细胞共转输组4T1荷瘤裸鼠肿瘤的生长明显快于CCR6Tregs共转输组和CD8+T细胞单转输组,同时该组荷瘤裸鼠生存时间也明显缩短（P<0.05）;CCR6+Tregs和CD8+T细胞共转输组CD8+T细胞的增殖、IFNγ的产生和颗粒酶B的表达均明显低于CCR6Tregs共转输组和CD8+T细胞单转输组（P<0.05）。结论：CCR6+Tregs在体内可以有效抑制CD8+T细胞的功能,其在肿瘤免疫逃逸和肿瘤发生、发展中发挥重要作用。     

非霍奇金淋巴瘤患者血中CD+4 CD+25 T细胞/CD+4 T细胞比率意义初探

  目的 探讨非霍奇金淋巴瘤（NHL）患者外周血中CD+4 CD+25 T细胞／CD+4 T细胞比率的意义。方法 应用流式细胞技术检测15例健康人、41例初诊NHL患者、16例CTOP方案化疗后完全缓解后的NHL患者及25例化疗后未达到完全缓解的患者单位体积内外周血中CD+4 CD+25 T细胞数量和CD+4 T细胞,计算CD+4 CD+25 T细胞占CD+4 T细胞的比率。结果 初诊NHL患者CD+4 CD+25 T细胞／CD+4 T细胞的比率为（7.54±2.31）％,高于健康者的（4.13±1.25）％（P＜0.05）;化疗完全缓解后NHL患者外周血CD+4 CD+25 T细胞／CD+4 T细胞的比率为（6.26±2.28）％,低于初诊化疗前患者的（7.54±2.31％）（P＜0.05）。化疗后未达到完全缓解患者CD+4 CD+25 T细胞／CD+4 T细胞的比率为（7.85±2.12）％,高于化疗后完全缓解的患者的比率（6.26±2.28）％（P＜0.05）。结论 化疗缓解后的NHL患者外周血中CD+4 CD+25 T细胞／CD+4 T细胞的比率较化疗前及化疗未缓解的患者降低,提示CD+4 CD+25 T细胞／CD+4 T细胞的比率可能与NHL患者免疫功能及治疗效果有关。     

Multipeptide stimulated PBMCs generate TEM/TCM for adoptive cell therapy in multiple myeloma

Multiple Myeloma (MM) patients suffer disease relapse due to the development of therapeutic resistance. Increasing evidence suggests that immunotherapeutic strategies can provide durable responses. Here we evaluate the possibility of adoptive cell transfer (ACT) by generating ex vivo T cells from peripheral blood mononuclear cells (PBMCs) isolated from MM patients by employing our previously devised protocols. We designed peptides from antigens (Ags) including cancer testis antigens (CTAs) that are over expressed in MM. We exposed PBMCs from different healthy donors (HDs) to single peptides. We observed reproducible Ag-specific cluster of differentiation 4⁺ (CD4⁺) and CD8⁺ T cell responses on exposure of PBMCs to different single peptide sequences. These peptide sequences were used to compile four different peptide cocktails. Naïve T cells from PBMCs from MM patients or HDs recognized the cognate Ag in all four peptide cocktails, leading to generation of multiclonal Ag-specific CD4⁺ and CD8⁺ effector and central memory T (T_EM and T_CM, respectively) cells which produced interferon-gamma (IFN-γ), granzyme B and perforin on secondary restimulation. Furthermore, this study demonstrated that immune cells from MM patients are capable of switching metabolic programs to induce effector and memory responses. Multiple peptides and cocktails were identified that induce IFN-γ⁺, T1-type, metabolically active T cells, thereby paving the way for feasibility testing of ACT in phase I clinical trials.     

Effector CD8+CD45RO-CD27-T cells have signalling defects in patients with squamous cell carcinoma of the head and neck

A subset of circulating T cells (CD8(+)CD45RO(-)CD27(-)) with a na?ve phenotype, but mediating effector function, is considered to play an important role in host antitumour defence. To investigate the attributes of these effector T cells in patients with squamous cell carcinoma (SCC) of the head and neck cancer, venous blood was obtained from 39 individuals with cancer and 45 normal controls (NC). Peripheral blood mononuclear cells were isolated, stained with labelled monoclonal antibodies specific for CD8, CD45RO, CD45RA, CD62L, CD27, TCR-zeta as well as isotype controls and examined by multicolour flow cytometry. Annexin V binding to CD8(+) T cells and PMA/ionomycin-induced IFN-gamma expression were also evaluated in patients and NC. The proportions of CD45RA(+)CD45RO(-) (na?ve) and CD45RA(-)CD45RO(+) (memory) cells were found to be comparable within the CD8(+) T-cell subset. However, relative to NC, the frequency of effector CD8(+)CD45RO(-)CD27(-) cells was strikingly increased in all SCC patients regardless of the disease status (P=0.0003). The proportion of these cells was found to increase with age in both patients and NC. In NC, stimulated IFN-gamma expression was largely restricted to CD8(+)CD45RO(-)CD27(+) cells, while in patients CD8(+)CD45RO(-)CD27(-) expressed IFN-gamma after ex vivo stimulation. Expression of the TCR-associated zeta chain was decreased or absent in freshly isolated CD8(+)CD45RO(-)CD27(-) T cells in patients (P<0.0001). Annexin V was found to bind to a higher proportion of circulating CD8(+) T cells in patients than NC (P<0.006), and significantly more Annexin V(+) T cells were present in the effector (P<0.0059) than the na?ve subset within the CD8(+)CD45RO(-) compartment. The data indicate that the expanded CD8(+)CD45RO(-)CD27(-) T cells, which contain precursors of IFN-gamma-producing T cells, are zeta-negative and sensitive to apoptosis in the circulation of patients with HNC.     

Herpes simplex virus (HSV) amplicon-mediated codelivery of secondary lymphoid tissue chemokine and CD40L results in augmented antitumor activity

Development of effective antitumor immune responses depends on timely interactions of effector cells. A bimodal approach that involves coexpression of chemokines and costimulatory molecules within the tumor bed may elaborate a more optimal antitumor response. One candidate includes secondary lymphoid tissue chemokine (SLC), which promotes the colocalization of na?ve, nonpolarized memory T cells and dendritic cells (DCs) within lymph nodes and Peyer's patches. CD40L-mediated DC activation could induce maturation, enhance antigen presentation, and facilitate priming of the recruited na?ve T cells. To this end, the antitumor activity of SLC and CD40L expressed singly or in combination using the herpes simplex virus (HSV)-derived amplicon was examined in two murine models: A20, a B-cell lymphoma, and CT-26, an adenocarcinoma. Administration of amplicons encoding SLC (HSV-SLC) into s.c. tumors established previously resulted in heavy infiltration of CD4+ and CD8+ T cells, and DCs, and the generation of cytolytic T-cell activity. Combined transduction of either tumor with HSV-SLC and HSV-CD40L resulted in a more enhanced antitumor activity that was CD8+ T cell-dependent than observed with either vector alone. mRNA expression of the Th1 markers IFN-gamma, perforin, and interleukin 12 was detectable only in transduced regressing tumors. In addition to identifying a potent antitumor immune strategy, we show that amplicon-mediated SLC and CD40L delivery may mimic lymph node conditions necessary for priming na?ve T cells within the tumor bed, and demonstrate the importance of DC activation status on antigen presentation and cytokine expression for priming of newly recruited T cells.     

幼稚和记忆T 细胞在NSCLC 放疗患者中的表达及其预后价值

  目的  探讨幼稚和记忆T细胞在非小细胞肺癌（non-small cell lung cancer,NSCLC）放疗患者外周血中的表达及其与预后的关系。  方法  采用流式细胞仪检测2014年9月至2016年5月解放军307医院40例接受放疗的NSCLC首诊患者,治疗前外周血中幼稚CD4+T细胞、记忆CD4+T细胞、幼稚CD8+T细胞、记忆CD8+T细胞,与14例健康人进行对比,并分析其与临床病理特征及预后的关系。  结果  与健康组相比,NSCLC患者幼稚CD4+T细胞下降（P=0.031）,记忆CD4+T细胞和记忆CD8+T细胞升高（P=0.014、0.005）。与不吸烟患者相比,吸烟患者幼稚CD4+T细胞较低（P=0.043）,记忆CD4+T细胞较高（P=0.024）。与ECOG评分1～2分者相比,0分者幼稚CD8+T细胞较低（P=0.017）,记忆CD8+T细胞较高（P=0.020）。单因素分析显示幼稚CD4+T细胞较高组放疗后中位无进展生存期（median progression free survival,mPFS）更长（17个月vs. 9个月,P=0.044）、记忆CD4+T细胞较高组放疗后mPFS可能更短（9个月 vs. 15个月,P=0.069）。Cox多因素分析显示幼稚CD4+T细胞与患者放疗后无进展生存期（progression free survival,PFS）独立相关（P=0.009）。  结论  NSCLC患者外周血中幼稚T细胞储备下降,记忆T细胞上升。幼稚CD4+T细胞较高可能预示放疗后PFS更长。      

Plasmacytoid dendritic cells induce CD8+ regulatory T cells in human ovarian carcinoma

To directly dissect the role of each immune component in human tumor immunopathogenesis, we have studied the interaction between dendritic cells and T cells in the tumor environment of patients with ovarian carcinoma. We previously reported that functional plasmacytoid dendritic cells, but not functionally mature myeloid dendritic cells, accumulated in tumor microenvironments. We now show that tumor ascites macrophage-derived dendritic cells induced tumor-associated antigen-specific CD8+ T cells with effector functions. Strikingly, tumor ascites plasmacytoid dendritic cells induced interleukin-10+ CCR7+ CD45RO+ CD8+ regulatory T cells. Four characteristics have been identified in tumor plasmacytoid dendritic cell-induced CD8+ regulatory T cells: (a) induction of CD8+ regulatory T cells is independent of CD4+ CD25+ T cells; (b) CD8+ regulatory T cells significantly suppress myeloid dendritic cell-mediated tumor-associated antigen-specific T cell effector functions through interleukin-10; (c) repetitive myeloid dendritic cell stimulation can recover CD8+ regulatory T cell-mediated poor T cell proliferation, but not T cell effector function; (d) CD8+ regulatory T cells express functional CCR7, and efficiently migrate with lymphoid homing chemokine MIP-3beta. Primary suppressive CCR7+ CD45RO+ CD8+ T cells are found in the tumor environment of patients with ovarian cancers. Thus, tumor-associated plasmacytoid dendritic cells contribute to the tumor environmental immunosuppressive network. Collectively, tumors manipulate tumor microenvironmental dendritic cell subset distribution and function to subvert tumor immunity. The data are relevant to understanding tumor immunopathology as well as reevaluating tumor immunotherapeutic strategies.     

Dynamic changes in immune cell profile in head and neck squamous cell carcinoma: Immunomodulatory effects of chemotherapy

Tumor cells have evolved sophisticated means of escape from the host immune system. To date, several important immunological phenomena have been revealed in peripheral blood as well as within tumors. In the present study, we first investigated the proportion and activation status of peripheral immune regulatory cells and CD8⁺ T‐cell subsets in patients with head and neck squamous cell carcinoma (HNSCC) using a multicolor flow cytometer, and then evaluated how therapy with docetaxel, cisplatin, and 5‐fluorouracil modulated the immune cell profile in peripheral blood. The proportion of naïve T cells was lower and that of effector memory T cells (T_EM) was higher in HNSCC patients than in healthy donors. Moreover, the proportions of activated T_EM cells and effector T cells (T_EFF) were dramatically increased in patients with advanced stage disease. The proportion of regulatory T cells and CD14⁺HLA‐DR^? myeloid‐derived suppressor cells was elevated in HNSCC patients. Of note, after therapy, in addition to the transient reduction in immune regulatory cells, decreases in central memory T cells and increases in T_EFF cells were observed among CD8⁺ T‐cell subsets, suggesting differentiation from central memory T cells into T_EFF cells. Our results suggested that, despite the immunosuppressive status in HNSCC patients, tumor‐specific immune responses mediated by CD8⁺ T cells might be induced and maintained. Moreover, chemotherapy can trigger not only a transient reduction in immune regulatory cells but also further activation of CD8⁺ T cells.     

Prognostic significance of T cell subsets in peripheral blood of B cell non-Hodgkin’s lymphoma patients

The role of tumor-infiltrating T cell subsets in the prognosis of non-Hodgkin's lymphoma (NHL) has previously been reported. In the present study, we investigated the prognostic significance of different T cell subsets in the peripheral blood of NHL patients. Immunophenotyping was performed on the peripheral blood samples of 45 patients with newly diagnosed B cell NHL using flow cytometry. The relationship between T cell subsets of CD4+, CD8+, CD3+CD25+, CD4+CD25+, CD4+CD25(high) [as T regulatory cells (T reg)], and the CD4/CD8 ratio with international prognostic index (IPI) and response to therapy was determined. The percentages of CD3+, CD4+, and CD8+?T cells in the peripheral blood of the patients were 49.1?±?20.3%, 23.6?±?11%, and 31.4?±?14.4%, respectively (CD4/CD8 ratio: 0.92?±?0.6). There were 4.2?±?3.2% T reg cells. A study of the percentage of T cells in relation to IPI score showed a higher proportion of CD3+CD25+, CD4+, and CD4+CD25+ cells in low-risk patients compared with intermediate/high risk groups (p?相似文献   

Bone marrow contains melanoma-reactive CD8+ effector T cells and, compared with peripheral blood, enriched numbers of melanoma-reactive CD8+ memory T cells

Circulating melanoma-specific T cells can be frequently detected in patients with melanoma. Effective T-cell immunity and tumor surveillance, however, requires the presence of specific T cells in tissues populated by tumor cells. The bone marrow (BM) is a compartment frequently harboring micrometastatic tumor cells. Here, we compared directly ex vivo in peripheral blood (PB) and BM frequencies and differentiation phenotypes of T cells reactive with the melanoma-associated antigen tyrosinase and with autologous melanoma cells. Using intracellular cytokine and tetramer staining, we detected tyrosinase- and melanoma-reactive CD3+CD8+ T cells in the BM in similar or enhanced frequencies as in PB. Additional characterization of the differentiation subset using CD45RA and CCR7 revealed the presence of specific effector and memory T cells in the BM in all five patients analyzed. Remarkably, the frequency of tyrosinase- and melanoma-specific memory T cells was significantly increased in BM compared with PB. Thus, the BM may be an important compartment for tumor surveillance harboring a tumor-specific memory T-cell pool in addition to effector T cells.     

Presence of circulating CCR10+ T cells and elevated serum CTACK/CCL27 in the early stage of mycosis fungoides.

PURPOSE: Mycosis fungoides (MF), a common type of cutaneous T cell lymphoma with an indolent clinical course, has the characteristic that malignant T cell clones are recruited into the skin from the early disease stages. The mechanisms of recruitment have been suggested from our knowledge of various chemokine-chemokine receptor interactions. Recently, CCR10 and CTACK/CCL27 were proposed to play a role in the recruitment of other types of cutaneous T cell lymphoma. We examined the expression of CCR10 in peripheral blood and serum CTACK/CCL27 levels in patients with MF. EXPERIMENTAL DESIGN: Eighteen patients with MF, six patients with atopic dermatitis, and nine healthy volunteers were enrolled in our investigation. We investigated the differences in CCR10+ CD4+ expression in peripheral blood mononuclear cells by flow cytometry. Serum CTACK/CCL27 levels were determined using a CTACK/CCL27 ELISA assay kit. RESULTS: The number of circulating CCR10+ CD4+ cells was significantly higher in MF peripheral blood than in controls, even during the early stages. In lesional MF skin, infiltrating tumor cells also showed extensive expression of CCR10. The serum level of CTACK/CCL27 was higher in patients with MF than normal controls, but no statistical difference was found compared with atopic dermatitis patients. CONCLUSIONS: CCR10-CTACK/CCL27 interactions between circulating T cells and keratinocytes would seem to play an important role in the pathophysiology of MF from the early disease stages.     

Chemokine C receptor 7 expression and protection of circulating CD8+ T lymphocytes from apoptosis.

Chemokine C receptor 7 (CCR7) expression is important for lymphocyte homing to tissues. We hypothesized that CCR7 also plays a role in CD8(+) T-cell protection from apoptosis. Its expression was determined on circulating T cells in patients with cancer and related to that of molecules responsible for lymphocyte susceptibility/resistance to apoptosis. Peripheral blood mononuclear cells were obtained from 36 patients with squamous cell carcinoma of the head and neck and 16 normal controls. Multicolor flow cytometry was used to evaluate CCR7, Fas, Bax, and Bcl-2 expression in CD8(+) T cells. Annexin V binding to CD8(+)CCR7(+) and CD8(+)CCR7(-) T-cell subsets was compared. Fewer CD8(+)CCR7(+) T cells bound Annexin V than CD8(+)CCR7(-) T cells in normal control and patients (P < 0.0001). CCR7 expression correlated with higher Bcl-2 but lower Bax and Fas expression levels in CD8(+) T cells in both normal control and patients (P < 0.0001). In patients, the CD8(+)CCR7(+) subset was reduced relative to normal control (P = 0.008) and replaced with an excess of apoptosis-sensitive CD8(+)CCR7(-) T cells. To study CCR7 signaling, CD8(+) T cells were stimulated with CCR7 ligands, chemokine C ligands 19 or 21. Ligand binding to CCR7 resulted in phosphorylation of Akt and increased Bcl-2 expression in CD8(+)CCR7(+) T cells, suggesting that CCR7 protects effector T cells from apoptosis through the phosphatidylinositol 3-kinase/Akt pathway. The absence of CCR7 expression on the majority of CD8(+) T cells in the peripheral circulation of patients with squamous cell carcinoma of the head and neck contributes to apoptosis and a rapid turnover of these effector cells.     

Memory t cell subsets in b cell non-hodgkin's lymphomas

Memory T cells were quantitated by three color flow cytometry in cell suspensions from biopsy specimens of 34 B cell non-Hodgkin's lymphomas (NHL) and 10 benign lymphoid hyperplasias (BLH). CD3+CD45RO-CD45RA+ (naive), CD3+CD45RO+CDRA- (memory) and total CD3+ T cells were compared in BLH, low grade (LG), intermediate (IG) and high grade (HG) B cell NHL. Mean percentage ± s.e. of CD45RO + T cells for BLH, LG, IG and HG NHL were: 14.7 ± 3.8, 11.2 ± 3.5, 28.9 ± 7.5 and 45 ± 15, respectively. Mean percentage ± s.e. of CD45RA + T cells were: 10.2 ± 2.6, 7.1 ± 2.3, 5.4 ± 1.4 and 3.5 ± 1.2, respectively. Mean percentage ± s.e. of total CD3+ T cells were: 42.5 ± 11, 22.4 ± 7.5, 39.3 ± 10.1 and 62.7 ± 22.2, respectively. Memory and total T cells progressively increased from LG toward IG and HG NHL while naive T cells simultaneously decreased. Although the differences in naive T cells were non-significant, the differences in memory T cells were significant between LG and IG and LG and HG NHL (both p .0100). We previously reported an increase in activated-cytotoxic T cells in IG -HG B cell NHL. We now report that this subset of lymphocytes has also acquired memory function. Future studies should determine if in vitro expansion and adoptive transfer of this subset of T cells results in tumor cytolysis.