鬼毛针多糖对小鼠细胞免疫功能影响的实验研究

20世纪80年代后多种真菌多糖的抑瘤活性被发现以来,真菌多糖作为一类新型药物引起越来越多的关注,成为一个非常活跃的研究领域。目前已证实多种真菌多糖可以通过激活T淋巴细胞、B淋巴细胞、活化巨噬细胞和NK细胞、激活补体、调节细胞因子分泌等对免疫系统发挥多方面的调节活性[     

双歧异黄酮奶粉对H22荷瘤小鼠化疗后的增效减毒作用研究

目的研究双歧异黄酮奶粉对环磷酰胺化疗后H22荷瘤小鼠抗肿瘤的增效减毒作用及其机制。方法构建H22荷瘤C57BL／6小鼠模型,研究双歧异黄酮奶粉对环磷酰胺化疗后的抑瘤率,取脾和胸腺计算脏器指数,双抗夹心ELISA法测定抑癌基因P27的表达及IL-2的水平以探索增效减毒机制。结果双歧异黄酮奶粉与环磷酰胺联合抗肿瘤具有增效减毒作用。可诱导抑癌基因P27的表达,增加IL-2的水平。结论双歧异黄酮奶粉与环磷酰胺联合抗肿瘤具有增效减毒作用。     

旋毛虫在小鼠体内发育及T淋巴细胞亚群变化的动态观察

目的观察IL-2对感染旋毛虫小鼠免疫功能的影响及旋毛虫在小鼠体内的发育。方法小鼠感染旋毛虫后,分别采用ELISA和流式细胞仪检测小鼠不同时期外周血中IL-2含量、CD4^＋及CD8^＋T淋巴细胞的百分率。取小鼠不同部位肌肉观察旋毛虫的发育和分布。结果小鼠感染旋毛虫后1～5周IL-2的含量较正常组明显增加。小鼠感染旋毛虫后1～6周,CD4^＋T细胞较正常组明显减少,CD8^＋T淋巴细胞明显增多,CD4^＋／CD8^＋比值明显下降。旋毛虫幼虫主要分布在小鼠的膈肌,其次为咬肌,舌肌最少。结论IL-2对感染旋毛虫小鼠早期具有一定的免疫抑制作用,小鼠感染旋毛虫后21d即可检出旋毛虫,35～42d密度达最高。     

126Gln is the residue of human IL-2 binding to IL-2R γ subunit

The 126Gln of human interleukin-2 (IL-2) is a conserved amino acid residue. After substitution of 126Gln with Asp, the binding abilities of this mutant to different composites of IL-2 receptor (R) subunits have been determined. Results show that 126AspIL-2 has higher affinity to IL-2R α β γ complex and normal affinity to IL-2R α β complex, but loses its binding ability to IL-2R β γ complex, demonstrating that the 126Gln is the residue of human IL-2 which binds to IL-2R γ subunit. Project supported by the “863” Project of China.     

The IL-2A receptor pathway and its role in lymphocyte differentiation and function

Murine myeloid cells are developed from hemopoietic stem/progenitor cells. Different types of progenitor cells have variable differentiation potentials. Among the ten main types of cells differentiated from lymphoid progenitor cells, regulatory T cells (Tregs), an important cell subpopulation regulating immune and inflammatory responses, arise from the hematopoietic stem cells in the bone marrow. Tregs then differentiate into T lymphocytes and migrate to the thymus and finally generate Treg subsets, which are subsequently activated and regulated by inflammatory cytokines in the peripheral blood. Tregs also have different phenotypes and immunomodulatory functions. The cytokine interleukin-2/interleukin-2 receptor (IL-2/IL-2R) pathway is an important regulatory signaling pathway of Tregs. Besides, different types of CD4⁺ and CD8⁺ cells have different immune effects in the absence of IL-2. IL-2R consists of three subunits, α chain (CD25), β chain (CD122), and γ chain (CD132). Different subunit combinations have different effects on the activation of immune cells. Multiple studies have shown that IL2RA deficiency has various effects on the immune function in mice. This article reviews the subunit composition and signaling pathway of IL-2R, the classification of Tregs in a murine myeloid cell line and the regulatory effect of IL-2/IL-2R on them, the regulatory impact and signaling mechanism of IL-2/IL-2R on CD4⁺/CD8⁺ lymphocyte differentiation, the primary manifestations and molecular mechanism of immune dysfunction in IL-2- and IL-2R-deficient mice, soluble IL-2Rα as a biomarker for diagnosis, prognosis and therapeutic efficacy of treatment in immune system disorders, and the development and clinical application of IL-2 mutants.     

上呼吸道病毒感染患者外周血中白介素-Ⅱ活性的检测

考察了上呼吸道病毒感染患者和正常人外周血白介素 Ⅱ (IL 2 )活性的变化情况。应用噻唑蓝比色法检测外周血IL 2的活性。结果显示 ,实验组 (4 9例 )IL 2的活性为 31.3± 0 .5 4 ,对照组 (4 2例 )的IL 2的活性为 6 4 .4± 0 .16。上呼吸道病毒感染患者外周血中的IL 2与正常人比较活性降低 ,存在显著性差异(P <0 .0 1)。     

白介素-2及干扰素-γ对人成骨细胞增殖的影响

体外培养人骨肉瘸细胞系MG63,MTT方法检测白介素-2（Interleukin-2,IL-2）和干扰素-γ（Interferon-γ,IFN-γ）对成骨细胞增殖的影响。结果表明,一定浓度（0．1—100U／μL）的IL-2能够促进成骨细胞增殖（P〈0．05）,而IFN-γ对成骨细胞增殖的影响无统计学意义（P〉0．05）,提示IL-2是成骨细胞的一种促分裂原。     

IBV S1基因和IL-2基因双顺反子DNA疫苗的免疫原性研究

为了研制更加有效的IBV DNA疫苗,将IBV的S1基因和禽白介素2(IL-2)基因插入双顺反子表达载体pIRES-EGFP/DsRed中,构建能分别或同时表达S1基因和IL-2基因的pIRES-S1、pIRES-IL2、pIRES-S1/IL-2质粒。通过脂质体转染Vero细胞,利用RT-PCR及间接免疫荧光检测表达。将构建的质粒用脂质体包裹后,通过腿部肌肉多点注射免疫7日龄雏鸡,二免后两周用IBV肾型强毒进行攻毒。结果表明,pIRES-S1/IL-2在体外能够诱导Vero细胞表达S1蛋白和IL-2;pIRES-S1/IL-2和pIRES-S1 pIRES-IL2免疫雏鸡后均能促进外周血T淋巴细胞亚群数量和血清中特异性抗体水平的增加,能明显增强IBV DNA疫苗对同型强毒的攻击保护,但pIRES-S1/IL-2免疫组要优于pIRES-S1 pIRES-IL2混合免疫组及其它对照组,差异显著或极显著。以上结果表明禽IL-2能同时加强DNA疫苗的细胞免疫和体液免疫应答;但抗原基因和IL-2共表达DNA疫苗的免疫效果明显要优于混合注射的DNA疫苗。     

CD4+CD25+调节性T细胞、IL-2与免疫耐受

近年来,越来越多的研究表明CD4+CD25+调节性T细胞在免疫耐受的过程中起着非常重要的作用。IL-2作为一种T细胞生长因子调控着调节性T细胞诱导免疫耐受的过程。IL-2维持着中枢及外周的调节性T细胞的活性,但是对胸腺调节性T细胞的发育是非必要的。同时,IL-2信号影响着调节性T细胞的功能并维持着其的竞争适应性。因此,CD4+CD25+调节性T细胞通过与IL-2之间形成的免疫网络调控着免疫耐受的过程,从而影响着机体的免疫平衡。     

肿瘤坏死因子-α和白介素-2对成骨细胞增殖的影响

成骨细胞在骨组织改建中至关重要。本试验体外培养人骨肉瘤细胞系MG63,MTT方法检测白介素-2(Interleukin-2,IL-2)和肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)对成骨细胞增殖的影响。结果表明,当IL-2的浓度大于100U/mL,其能够促进成骨细胞增殖(P0.05),一定浓度(50～1000U/mL)的TNF-α对成骨细胞的增殖也有促进作用。     

蜜环菌多糖对小鼠血清IL-2和TGF-β1水平的影响

目的:观察蜜环茵多糖对小鼠血清中IL-2和TGF-β1水平的干预作用。方法:实验组小鼠腹腔注射(i.p)不同浓度的蛮环菌多糖,阴性对照组给予生理盐水,阳性对照组给予香菇多糖,连续给药14天。给药结束后,用形态学方法测定各组小鼠在植物血凝素(PHA)诱导下淋巴细胞转化率,用ELISA法测定各组小鼠血清中白介素2(IL-2)、转化生长因子β1(TGF-β1)水平。结果:蜜环菌多糖具有提高小鼠淋巴细胞转化率,增加血清中IL-2水平,并同时下调血清中TGF-β1水平的作用。结论:蜜环菌多糖可通过调节小鼠免疫细胞及免疫分子的作用,增强小鼠的免疫功能。     

两种新型白细胞介素-2的热稳定优越性

研制成两种新型白细胞介素-2(新型IL-2),其一为125Ser-IL-2,另一为125Ala-IL-2(即原型IL-2中125位Cys分别被Ser或Ala取代)。两种新型IL-2均已被高度纯化,并已完成了中试,获准临床应用。发现新型IL-2的热稳定优越性。在65℃加热,新型IL-2的稳定性高于原型,失活比原型慢,被保留的活性也较原型多。在0.1％SDS中能使失活的IL-2逐渐恢复一定的活性,也是新型IL-2恢复活性高。同时,比较了其它条件下这三种重组rIL-2的稳定性及SDS对其复性的影响,发现三者之间差异很大。上述结果均证明:125Ala-IL-2的热稳定性最好,125Ser-IL-2次之,原型较新型差。     

Difference in response of NK cell activity in newborns and adult to IL-2, IL-12 and IL-15

The killing activity of cord blood mononuclear cells (cMNC) against cytomegalovirus (CMV)-uninfected and -infected fibroblasts was comparable to that of adult peripheral blood mononuclear cells (aPBMC). The killing activity of cMNC against K562 cells was significantly lower compared with that of aPBMC. Treatment of cMNC and aPBMC with interleukin-2 (IL-2), IL-12 or IL-15 significantly enhanced killing activity against K562 cells and CMV-uninfected and -infected cells. By comparison of cMNC with aPBMC, killing activity against the K562 cells of cMNC was augmented to the level of aPBMC when cultured with IL-2, IL-12 or IL-15. The killing activity of cMNC against CMV-uninfected and -infected fibroblasts did not increase to the level of adult PBMC by treatment with IL-2, IL-12 or IL-15. These data suggest that cord blood contains a functionally different NK cell subpopulation than that among adult NK cells.     

Constitutive expression of IL-2Rbeta chain and its effects on IL-2-induced vascular leak syndrome

IL-2-induced vascular leak syndrome (VLS) is an important mechanism explaining the toxic effects of this cytokine and limiting its therapeutic use. We previously characterized a mouse model of IL-2-induced pulmonary VLS used to demonstrate that NK lymphocytes are involved in early/acute phase VLS (after one IL-2 injection). We also showed that NK cells and polymorphonuclear neutrophils (PMN) are involved in the late/chronic phase of the syndrome (after four daily IL-2 injections). In this study we use our mouse model to evaluate the role played by the IL-2 receptor (IL-2R) in VLS induction. Mouse and human IL-2R are different since the mouse IL-2Rbeta chain does not recognize IL-2. Here, we compare the acute and late VLS responses in human IL-2Rbeta transgenic and C57BL/6 wild type mice. Parameters linked to early phase VLS (bronchoconstriction and PMN mobilization) are enhanced in human IL-2Rbeta transgenic mice. By contrast, parameters used to measure late events (protein leakage and edema) are similar in human IL-2Rbeta transgenic mice and C57BL/6 wild type animals. However, after four IL-2 injections, the cellular content of the bronchoalveolar lavage fluids was different between the two types of animals. This study also characterizes a humanized animal model that could be further used to study human IL-2 activity and side effects in vivo.     

Large intra-individual variability of plasma cytokines in healthy young men: a two 24-h study over a month

Cytokine levels in blood are not yet fully considered as biomarkers for disease even if some significant progresses have been made in linking certain cytokines to some diseases. The aim of this study was to look for the stability of some cytokines in blood collected in two different days separated by one month. Fifteen healthy young men aged 20–30 years were selected for this study. Each subject participated in two 24-h sessions spaced a month apart. Blood sample was taken at 11:00, 17:00, 22:00, 01:00, 04:00, 06:00, and 08:00. Concentrations of interleukin-6, interleukin-1-receptor antagonist, soluble IL-2 receptor, interleukin-1 beta, and interleukin-2 were measured in serum. The circadian pattern of each variable was compared between the two days. The results show that there is no reliability for the measured cytokines. This study shows that cytokine levels measured in blood are neither reliable variables nor considered as stable markers in healthy subjects.     

Effect of exposure to interleukin-21 at various time points on human natural killer cell culture

Background aimsInterleukin-21 (IL-21) can enhance the effector function of natural killer (NK) cells but also limits their proliferation when continuously combined with IL-2/IL-15. Paradoxically, membrane-bound (mb)-IL-21 has been shown to improve human NK cell proliferation when cultured with IL-2/mb-IL-15. To clarify the role of IL-21, we investigated the effect of the timing of IL-21 addition to NK cell culture.MethodsIL-2/IL-15–activated NK cells were additionally treated with IL-21 according to the following schedules; (i) control (without IL-21); (ii) first week (day 0 to day 7); (iii) intermittent (the first 3 days of each week for 7 weeks); (iv) after 1 week (day 8 to day 14); and (v) continuous (day 0 to day 49). The expression of NK receptors, granzyme B, perforin, CD107a, interferon-γ, telomere length and NK cell death were measured by flow cytometry.ResultsCompared with the control (2004.2-fold; n = 10 healthy donors) and intermittent groups (2063.9-fold), a strong proliferative response of the NK cells on day 42 was identified in the “first week” group (3743.8-fold) (P < 0.05). NK cells treated with IL-21 in the “first week” group showed cytotoxicity similar to that in control cells. On day 28, there was a significant increase in cytotoxicity of “first week” NK cells that received IL-21 treatment for an additional 2 days compared with the “first week” NK cells (P < 0.05).ConclusionsThese data suggest that controlling temporal exposure of IL-21 during NK cell proliferation can be a critical consideration to improve the yields and cytotoxicity of NK cells.     

Suppression of IL-2-induced SAA gene expression in mice by the administration of an IL-1 receptor antagonist

The hepatic acute phase response induced by the administration of interleukin (IL)-2 is most likely mediated by secondary cytokines. In this investigation, we examined the role of endogenous IL-1 in the synthesis of the hepatic acute phase protein serum amyloid A (SAA) during IL-2 treatment. The injection of IL-2 induced SAA gene expression in the liver. The concurrent administration of an IL-1 receptor antagonist (IL-1RA) markedly reduced hepatic SAA mRNA levels and, to a lesser extent, SAA protein levels in the serum. Although IL-1 is an inducer of IL-6 production, the administration of the IL-1RA had no effect on circulating IL-6 levels in IL-2-treated mice. These findings suggest that the production of IL-1 is an important factor in the induction of SAA mRNA in mice undergoing immunotherapy with IL-2.     

Characterization of a subclone (D10S) of the D10.G4.1 helper t-cell line which proliferates to attomolar concentrations of interleukin-1 in the absence of mitogens

Most studies have shown that interleukin-1 (IL-1) acts as a helper or co-stimulator in T-lymphocyte activation and proliferation by mitogens or antigens. We describe here a stable subclone (D10S) of the murine D10.G4.1 helper T-cell which proliferates to subfemtomolar (attomolar) concentrations of IL-1 beta or alpha in the absence of mitogens. D10S cells have been maintained in culture for over two years without splenic cell feeder layers nor antigen stimulation. Detection of proliferation can be made by either uptake of tritiated thymidine at 72 h or in 48 h by a colorimetric assay which measures mitochondrial dehydrogenases; the latter assay is rapid and inexpensive. D10S cells are distinct from the parent clone D10.G4., which requires mitogens for IL-1 activity. IL-1-induced proliferation is independent of the elaboration of IL-2, IL-4, or IL-6, although these cells proliferate to these lymphokines at considerably higher concentrations when compared to IL-1. The D10S cells proliferate in direct correlation to the duration of IL-1 presence in the culture. We found no evidence that IL-1 induced more IL-1 in these cells. The subclone is highly specific for IL-1: proliferation was not observed to endotoxin, human or murine interferon-gamma (IFN gamma), tumor necrosis factor (TNF), lymphotoxin, or granulocyte-macrophage colony stimulating factor (GM-CSF). There was no suppressive effect of transforming growth factor (TGF beta). Only at high concentrations (100 ng/ml) did IL-6 induce proliferation. We conclude that this stable, feeder layer-free cell line is highly sensitive to IL-1 which acts as a direct stimulant for these cells; they are also useful for bioassays as well as the study of IL-1 receptors as described in the accompanying paper.     

Production of tumor necrosis factor α and interferon γ in interleukin-2-treated melanoma patients: Correlation with clinical toxicity

Summary Interleukin-2 (IL-2)-based immunotherapy regimens are accompanied by dose-limiting toxicity consisting of fever, tachycardia, chills and capillary leak syndrome. We hypothesized that the toxicity was caused by the induction and release of endogenous cytokines such as tumor necrosis factor (TNF) and interferon (IFN). We measured the serum levels of TNF and IFN in IL-2-treated melanoma patients and attempted a correlation with clinical toxicity. A total of 23 patients received either 6 × 10⁶ IU or 12 × 10⁶ IU Cetus IL-2/m² by i. v. bolus daily for 5 consecutive days on weeks 1, 3 and 5. Serum TNF and IFN levels were measured by enzyme-linked immunosorbent assay. Clinical toxicity was scored each day by objective measurements of hypotension, tachycardia, fever and chills/rigors. Clinical toxicity and IFN levels correlated nicely, peaking on the 5th day of each treatment cycle. The kinetics and magnitude of TNF production, however, were not predictable and did not correlate with either IFN or toxicity. Some patients had modest increases in TNF production while others had markedly increased levels during the second and third treatment weeks. Remarkably, these high levels persisted during nontreatment weeks and after completion of therapy. This clinical study demonstrates novel kinetics for immunoreactive TNF in IL-2 cancer patients, which do not correlate well with toxicity.This work was supported by NIH Grants CA 50 780 (J. E.) and CA 29 605, CA 12 582 (D. L. M.) and the U. C. Tobacco-Related Disease Research Program RT-62 (J. E.). J. E. is the recipient of an NCI Clinical Investigator Award (KO8-01360) and is a Dorothy and Leonard Straus Scholar at UCLA