Enhancement of Antitumor Immunity after Propofol Treatment in Mice

Propofol and midazolam are the most widely used sedatives in the intensive care setting after surgery. We studied whether these sedatives had any antitumor immunity effects in mice. Mice were given intraperitoneal injections of propofol or midazolam and subcutaneous inoculation of tumor cells (EL4). Then, spleen cells were collected and the in vitro activity of cytotoxic T lymphocytes (CTL) was measured using flow cytometry. The in vitro activity of CTL against EL4 was significantly greater after propofol injection compared with its vehicle (Intralipid) or saline. Midazolam had no effect on CTL activity. We also studied whether tumor growth in vivo was affected by the administration of propofol. Tumor growth was significantly suppressed in mice that were given propofol, compared with tumor growth in mice given saline. Therefore, it is concluded that propofol may have a beneficial effect on antitumor immunity in mice.     

Effect of Subhypnotic Doses of Dexmedetomidine on Antitumor Immunity in Mice

Dexmedetomidine, a selective α2 adrenergic receptor agonist, is a drug often used for sedation. Despite the high prevalence of sedating patients with tumors in intensive care settings, little is known about the effect of sedative drugs on tumor growth. We studied the effect of dexmedetomidine on antitumor immunity in mice. Subhypnotic doses of dexmedetomidine decreased interleukin (IL)-12 production from thioglycollate-induced macrophages. The treatment also decreased the ratio of the helper T lymphocytes subsets, Th1 to Th2 (Th1/Th2), in the spleen. Following subcutaneous inoculation of EL4 T-cell lymphoma cells, dexmedetomidine further decreased the splenic Th1/Th2 ratio and activity of EL4-specific cytotoxic T lymphocytes (CTLs). Finally, treatment with dexmedetomidine accelerated EL4 growth in mice. These data show that treatment of mice with subhypnotic doses of dexmedetomidine downregulates antitumor immunity, possibly through the decreased production of IL-12 from antigen presenting cells, resulting in a Th2 shift and decreased CTL activity against EL4 in mice.     

A new flow cytometric assay for the simultaneous analysis of antigen-specific elimination of T cells in heterogenous T cell populations

Novel immunosuppressive strategies are targeting for an antigen-specific deletion of T cells responsible for organ damage in autoimmunity and allograft rejection. Here, we present a new flow cytometry-based assay that allows the reliable and efficient detection of T cells that were eliminated in an antigen-specific fashion. A stable cell-labelling technique utilizing the two membrane dyes PKH26 and PKH67 has been combined with annexin V and 7-aminoactinomycin (7-AAD) staining to detect apoptotic cells. A differential gating strategy enabled us to determine the viability/apoptosis for each PKH-stained T cell subpopulation independently. The capability to simultaneously analyze apoptosis within T cell mixtures of different antigen specificities establishes this assay as a superior tool for the further development of novel antigen-specific immunosuppressive approaches.     

The VITAL assay: a versatile fluorometric technique for assessing CTL- and NKT-mediated cytotoxicity against multiple targets in vitro and in vivo

Assessment of cell-mediated toxicity has traditionally been achieved by measuring the specific activity of enriched effector cell populations against antigen-loaded target cells labeled with radioactive isotopes in vitro. Fluorometric techniques are viewed as a promising alternative to the use of radioactive isotopes for these analyses. Direct assessment of cytotoxicity in vivo can be achieved by monitoring survival of injected fluorescent targets relative to a differentially labeled internal control population without specific antigen. We have developed this approach, incorporating the use of multiple target cell populations labeled with different dyes so that cytotoxicity can be assessed against titrated doses of a given antigen, or against a range of different antigens, simultaneously. We show that this assay, referred to as the VITAL assay, can be used to assess cytotoxic activity of CTL and iNKT cells in vivo and in vitro. CTL responses measured in vivo could be correlated with antigen doses used in immunization strategies, and also with the size of specific CTL populations enumerated in the blood with fluorescent MHC/peptide tetramers. The VITAL assay is, therefore, a sensitive technique allowing analysis of complex multi-epitope responses.     

Effect of a Novel Antineoplastic Drug Olipifat on Antitumor Immunity in Mice

Olipifat is an antineoplastic drug containing pyrophosphate and a product of special lignin processing. Donor C57Bl/6J mice with syngeneic B16 melanoma received a single 5-day course of olipifat. Effect of olipifat on antitumor resistance was evaluated by local neutralization test [3]. In animals with rapid melanoma growth, splenic cells from intact donors stimulated tumor growth. Olipifat abolished this growth-stimulating effect of splenocytes. In animals with slow melanoma growth, splenocytes had no effect on the growth of melanoma or Lewis lung cancer. In this case, splenocytes from olipifat-treated donors completely arrested the growth of melanoma B16 and decelerated the growth of Lewis lung carcinoma.     

艾滋病患者T淋巴细胞表面归巢分子的表达在抗病毒治疗后升高

目的 探讨艾滋病(AIDS)患者高效抗反转录病毒治疗(HAART)前后T淋巴细胞表面归巢分子CD49d、CCR9、CD62L表达的变化情况.方法 采用流式细胞术检测42例艾滋病患者和18例HIV阴性健康对照的外周血T淋巴细胞表面CD49d、CCR9和CD62L表达,用BD FACSDiva软件分析计算各组细胞表达的百分率.结果 治疗后组外周血的平均CD4~+T淋巴细胞明显高于治疗前组(P<0.01);治疗前组CD3~+CD49d~+、CD3~+ CCR9~+、CD3~+CD62L~+、CD3~+CD4~+、CD4~+CD49d~+、CD4~+CCR9~+、CIM~+CD62L~+、CD8~+CD49d~+、CD8~+CD62L~+T淋巴细胞的百分率显著低于治疗后组和阴性对照组(P<0.05);CD3~+CD8~+T淋巴细胞的百分率高于治疗后组(P<0.05).治疗后组CD3~+CCR9~+、CD8~+CCR9~+、CD8~+CD62L~+T淋巴细胞的百分率均低于阴性对照组(P均<0.001).结论 AIDS患者外周血T淋巴细胞亚群不仅比例失调,而且其表面表达肠道归巢分子CD49d、CCR9,淋巴结归巢分子CD62L的数量发生异常改变.抗病毒治疗可以逆转以上部分免疫病理变化.建议肠道归巢分子CD49d、CCR9和淋巴结归巢分子CD62L可作为艾滋病疾病进展和评价机体HAART后免疫重建的指标.     

Expansion of activated T lymphocytes (CD3+HLA/DR+) detectable in early stages of HIV-1 infection

Summary The phenotypic characterization of lymphocyte subsets in relation to different clinical stages of HIV infection has mainly focussed on CD4 and CD8 cells. Some reports focus on expansion of activated T lymphocytes in AIDS patients. Yet there is no detailed knowledge whether such changes occur also in earlier stages of HIV infection. In order to describe the kinetics and possible pathogenetic meaning of this subset when related to all distinct chronologic stages, we performed two-color flow cytometric lymphocyte differentiation in 173 HIV-infected patients and 30 healthy controls. All subjects were classified according to the Walter Reed (WR) system. Our results show that a significant increase of activated T lymphocytes (CD3+HLA/DR+) occurs early, in WR1 and WR2, thus preceding the clinically relevant CD4 depletion. This increase is paralleled by an expansion of CD 8+Leu7+cytotoxic cells. We conclude, thatearly changes of lymphocyte subsets are detectable in addition to inversion of the CD4/ CD8 ratio. The possible pathogenetic meaning including the question of possible autoimmune mechanisms is discussed.Abbreviations AIDS acquired immunodeficiency syndrome - ARC AIDS-related complex - CD cluster of differentiation - FITC fluorescein isothiocyanate - HIV human immunodeficiency virus - MAB monoclonal antibodies - NK natural killer - PBMC peripheral blood mononuclear cells - PE phycoerythrin - SEM standard error of the mean     

淫羊藿甙对小鼠T淋巴细胞体外活化和增殖的影响

目的研究淫羊藿甙(ICA)对刀豆蛋白A(ConA)刺激的小鼠T淋巴细胞体外早期活化和增殖的影响。方法以MTT法检测T细胞药物毒性;利用流式细胞术(FCM)结合双色荧光抗体染色技术检测早期活化标志CD69分子的表达;运用流式细胞术结合活体染料羧基荧光素乙酰乙酸(CFDA-SE)染色技术和荧光抗体染色技术检测T细胞增殖。结果ICA在终浓度0.3、1.5、3.0μmol·L-1时对于CD69的表达以及淋巴细胞48和72h增殖,均有明显的抑制作用(P<0.01)。结论ICA能抑制ConA刺激的小鼠T淋巴细胞的早期活化和增殖,并呈剂量依赖性,即在最高浓度3.0μmol·L-1时抑制率最强。     

SARS患者急性期外周血CD3+、CD4+及CD8+细胞数量的变化

目的 探讨SARS患者外周血T淋巴细胞亚群的变化及其临床意义。方法 用全自动血细胞分析仪检测44例SARS患者外周血白细胞计数及分类，用流式细胞仪检测SARS患者外周血T淋巴细胞亚群；并与正常对照组比较。结果 与对照组比较，SARS组患者白细胞总数显著下降，淋巴细胞百分数和绝对数显著下降，粒细胞绝对数显著下降，粒细胞百分数显著增加；CD3^ 、CD4^ 和CD8^ 细胞绝对数显著下降，CD3^ 、CD4^ 及CD8^ 细胞百分数和CD4^ /CD8^ 比值与对照组比较无显著性差异。结论 SARS冠状病毒感染损伤患者细胞免疫功能。     

The Shiga toxin B-subunit targets antigen in vivo to dendritic cells and elicits anti-tumor immunity

The non-toxic B-subunit of Shiga toxin (STxB) interacts with the glycolipid Gb3, which is preferentially expressed on dendritic cells (DC) and B cells. After administration of STxB chemically coupled to OVA (STxB-OVA) in mice, we showed that the immunodominant OVA(257-264) peptide restricted by K(b) molecules is specifically presented by CD11c+ CD8alpha- DC, some of them displaying a mature phenotype. Using mice carrying a transgene encoding a diphtheria toxin receptor (DTR) under the control of the murine CD11c promoter, which allows inducible ablation of DC, we showed that DC are required for efficient priming of CTL after STxB-OVA vaccination. Immunization of mice with STxB-OVA induced OVA-specific CD8+ T cells detected ex vivo; these cells were long lasting, since they could be detected even 91 days after the last immunization and were composed of both central and memory T cells. Vaccination of mice with STxB-OVA and STxB coupled to E7, a protein derived from HPV16, inhibited tumor growth in prophylactic and therapeutic experiments. This effect was mainly mediated by CD8+ T cells. STxB therefore appears to be a powerful carrier directly targeting DC in vivo, resulting in a strong and durable CTL response associated with tumor protection.     

特异性细胞毒性T细胞检测方法的建立及其在重组痘苗病毒活疫苗细胞免疫研究中的应用

报道了用ＣＢＡ／Ｊ小鼠、Ｌ９２９细胞及ＭＴＴ比色法建立的特异性细胞毒性Ｔ细胞（ＣＴＬ）的检测方法及其在重组痘苗病毒活疫苗细胞免疫研究中的应用。通过检测痘菌病毒特异性初发ＣＴＬ的动态变化及其二次反应ＣＴＬ，表明，本法能较好地检测初发及二次反应ＣＴＬ水平的变化。用本法检测了不同启动子控制下的表达Ｅｐｓｔｅｉｎ－Ｂａｒｓ（ＥＢ）病毒膜抗原（ＥＢＶ－ＭＡ）的重组痘菌病毒ＥＢＶ－ＭＡ特异性ＣＴＬ、以及与表达人白细胞介素－２的重组痘苗病毒联合免疫时的ＥＢＶ－ＭＡ特异性ＣＴＬ。结果表明，Ｐ７５００启动子表达的ＥＢＶ－ＭＡ比Ｐ１１０００启动子表达的ＥＢＶ－ＭＡ诱导的ＥＢＶ－ＭＡ特异性ＣＴＬ高，但无显著性差异。当上述重组痘苗病毒与表达人白细胞介素－２的重组痘苗病毒联合免疫时，均能使二者的ＥＢＶ－ＭＡ特异性ＣＴＬ增高，但增高幅度本身及其二者之间均无显著性差异。     

Selection of T cell receptor variable gene-encoded amino acids on the third binding site loop: a factor influencing variable chain selection in a T cell response

The 3′ end of the T cell receptor Vβ7.1 gene contains the five nucleotides CAAGA between the broadly conserved consensus sequence of nucleotides TGC/T GCC AGC AGC (which encode cysteine, alanine, serine and serine at positions 92–95 of the β chain) and the heptamer that signals rearrangement. These nucleotides are frequently preserved during gene rearrangement, resulting in the common presence of glutamine at position 96 and of aspartate or glutamate at position 97 of the Vβ7.1 chain CDR3 loop in peripheral blood lymphocytes. There is selection of Vβ7.1 and of the Vβ7.1 gene-encoded glutamate at position 97 of the β chain CDR3 loop in the cytotoxic T lymphocyte response to the HLA B2705-restricted influenza A nucleoprotein epitope SRYWAIRTR. Our results indicate that selection of Vβ7.1 gene-encoded amino acid residues on CDR3 loops may be one factor driving selection of Vβ7.1 in this response.     

Immunomodulatory effects of selenium and vitamin E on alterations in T lymphocyte subsets induced by T-2 toxin

Context: T-2 toxin, a potent mycotoxin, has serious effects on immune system.

Objective: Here, the effects of a sublethal dose of this toxin on T lymphocyte sub-population levels and the potential protective effects from treatment with selenium or vitamin E were studied.

Materials and methods: After having determined the sublethal dose of the T-2 toxin in Balb/c mice hosts, the post-injection kinetics of changes in T lymphocyte sub-population (CD3⁺, CD4⁺ and CD8⁺ cells) profiles were analyzed via flow cytometry. For these studies, the selenium and vitamin E were either provided to the mice before or concurrent with the toxin.

Results: The results show that after a sublethal dose of T-2 alone, the number of CD8⁺ T-lymphocytes was significantly decreased at 12?h and normalized at 48?h. In contrast, level of CD3⁺ and CD4⁺ T-lymphocytes were significantly increased at 24?h and returned to normal after 48?h. When selenium was injected into the mice 24?h before or concurrent with the T-2, the effects on CD8⁺ cells were mitigated. Oddly, only when the selenium was given with the toxin could the effects on the CD3⁺ and CD4⁺ cells be altered. Vitamin E, when injected 24?h before or concurrent with the T-2 toxin, was only able to impact upon the CD8⁺ lymphocyte alterations induced by the toxin.

Conclusions: Compared with vitamin E, it seems that selenium could assert an important effect against the immunotoxic effects of T-2 toxin against T lymphocytes.     

使用活化诱导标记法评价HIV-1感染者特异性CD4+T细胞免疫应答的研究

目的:建立一种检测HIV-1特异性CD4⁺T细胞亚群功能的活化诱导标记法(activation-induced markers,AIM),从而更有效地评价HIV-1抗原特异性CD4⁺T细胞免疫应答水平。方法:选取12例未经抗病毒治疗的HIV-1慢性感染者及6例未感染HIV-1的健康人,分别以基于多色流式细胞术的AIM法和细胞内因子染色法(intracellular cytokine staining,ICS)检测抗原特异性T淋巴细胞功能,并探讨两种方法用于评价HIV-1感染者抗原特异性T细胞免疫应答的能力。结果:AIM法检测HIV-1慢性感染者中HIV-1抗原特异性PD-1⁺CD25⁺CD4⁺T、CD69⁺CD200⁺CD4⁺T、CD69⁺ICOS⁺CD4⁺T细胞阳性的比例为11/12、8/12和7/12,检测CD69⁺ICOS⁺CD8⁺T、CD137⁺CD69⁺CD8⁺T、PD-1⁺CD25⁺CD8⁺、OX40⁺PD-1⁺CD8⁺T细胞阳性的比例为8/12、8/12、7/12、7/12。ICS法检测HIV-1抗原特异性IL-2⁺CD4⁺T、IFN-γ⁺CD4⁺T、TNF-α⁺CD4⁺T细胞阳性的占比为2/12、2/12、0;IFN-γ⁺CD8⁺T、TNF-α⁺CD8⁺T、IL-2⁺CD8⁺T细胞阳性的占比为12/12、10/12、5/12。结论:AIM法在评价CD4⁺T细胞功能方面更为敏感,可作为ICS法的补充,两种方法联合使用可更全面地评估抗原特异性T淋巴细胞反应。     

CD8+ cytolytic T lymphocytes become infected in vitro in the process of killing HIV-1-infected target cells

In the present study the requirements for in vitro infection of antigen-specific CD8⁺ cytotoxic T lymphocytes (CTL) with human immunodeficiency virus –1(HIV-1) were investigated. CD3⁺CD8⁺CD4^? HIV-1 nef-specific CTL become infected with HIV-1 after short-term co-culture with HLA-matched HIV-1-infected CD20⁺ B lymphoblastoid cells (B-LCL) which are specifically killed. Similar results were observed with an allospecific CD8⁺ CTL population. In addition, co-culture experiments showed that once infected with HIV-1, these CD8⁺ CTL could spread the infection further to uninfected CD4⁺ lymphocytes. In contrast, CD8⁺ CTL did not become infected with HIV-1 when co-cultured with HLA-mismatched HIV-1-infected B-LCL which are not killed. These observations in vitro could have relevance in peripheral lymphoid organs contributing to the progressive decrease of HIV-specific CD8⁺ CTL activity that is associated with the progression to AIDS.     

Immunity Parameters in Mice of Different Strains

Quantitative composition and functional activity of immunocompetent cells differ in mice of different strains. The counts of T cells in the bone marrow and spleen, proliferative activity of T cells in the spleen, levels of IL-2 and IL-10 production by splenic T cells, number of antigen-specific T cells and their functional activity are low in C57Bl/6, BALB/c, and CC57W mice and high in CBA/CaLac, DBA/2, and C3H animals. Low phagocytic activity of peritoneal macrophages was detected in BALB/c and CC57W mice and high activity in C3H animals. The content of antibody-producing cells in the spleens of C57Bl/6, BALB/c, and CC57W mice is higher than in CBA/CaLac, DBA/2, C3H, A/SN, and AKR/JY mice. Functional activity of B cells is lower in BALB/c and CC57W compared to CBA/CaLac and DBA/2 mice. __________ Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 140, No. 8, pp. 189–191, August, 2005     

宫颈癌放疗前后免疫功能改变及其临床意义

目的 :探讨放疗对宫颈癌患者免疫功能的影响。方法 :用流式细胞技术检测 2 2例宫颈癌患者放疗前后细胞免疫表型的改变 ,并与对照组进行比较。结果 :宫颈癌放疗前CD3 、CD4 、CD8 、CD3 CD4 均较对照组低 ,NK值较对照组高 ,但无显著性差异 ;放疗后CD3 、CD4 逐渐降低 ,CD8 和NK升高 ,CD3 CD4 逐渐降低 ,最后比例倒置 ,有显著性差异。结论 :宫颈癌患者免疫功能无明显抑制 ,放疗可损伤其免疫功能 ,提示放疗期间应辅以免疫治疗。     

Mucosal Immunity in the Human Female Reproductive Tract: Cytotoxic T Lymphocyte Function in the Cervix and Vagina of Premenopausal and Postmenopausal Women

PROBLEM: To investigate the mucosal immune system in the cervix and vagina of premenopausal women in terms of immune cells present and cytolytic capacity of mucosal CD3+ T cells in the lower reproductive tract. METHODS: Fresh tissue fragments prepared by vibratome sectioning were analyzed for the presence of immune cells by confocal scanning laser microscopy (CSLM). Isolated reproductive tract cells prepared by enzymatic digestion were analyzed for CD3+ T cell phenotype by FACS analysis and for cytolytic function by an anti-CD3 mAb mediated redirected lysis assay. RESULTS: As determined by CSLM, CD3+ cells as well as macrophages and dendritic cells are distributed throughout the lower female reproductive tract in both the epithelium and subepithelial mucosa. It was found that cervical and vaginal tissues from pre- and post-menopausal women contain CD3+ T cells (CTL) that have cytolytic activity, when measured in an antigen non-specific anti-CD3 mAb mediated redirected lysis assay. CONCLUSIONS: These results indicate that the lower reproductive tract of women is immuno-competent as judged by the presence of CD3, CD4, CD8, macrophage, and dendritic cells in the endocervix, ectocervix, and vagina of premenopausal and postmenopausal women. Further, these studies demonstrate that CD3+ T cells with cytolytic activity are present in the cervix and vagina during the proliferative and secretory phases of the menstrual cycle and following menopause.