慢性肺心病患者NK细胞活性及其对IL-2、IFN-γ的反应

本文检测30例慢性肺心病患者外周血NK细胞活性,并探讨重组人IL-2、IFN-γ在体外对患者NK细胞活性的影响。结果发现肺心病患者NK细胞活性明显低于正常对照组(p<0.01),且在急性加重期NK细胞活性下降更为显著,IL-2、IFN-γ在体外能明显提高肺心病患者的NK细胞活性。     

干扰素对受照射机体NK细胞活性的调节作用

采用4h51Cr释放法,分别以小鼠脾脏淋巴细胞对YAC-1细胞和肿瘤患者外周血淋巴细胞对K562细胞的体外自然杀伤（NK）活性为指标,研究受电离辐射后小鼠脾脏NK细胞活性的变化以及干扰素（IFN－α）对NK细胞活性的影响;并观察肿瘤患者及其放疗后NK细胞活性的变化以及IFN－α的调节作用。结果表明NK细胞具有较强的辐射耐受性,经16Gy照射后24hNK细胞活性显著降低;肿瘤患者的NK细胞活性明显低于正常对照组（P＜0．01）,放疗后NK细胞活性进一步降低（P＜0．05）。IFN－α处理NK细胞可以显著增强NK细胞活性,这提示IFN-α有可能作为一种生物应答调节剂用于肿瘤患者、肿瘤放、化疗或手术患者。     

慢性乙肝患者NK,ADCC活性及其对IFN—α,IFN—γ的反应

本文用Hela细胞乳酸脱氢酶释放法测定了42例慢性乙肝病人外周血NK、ADCC活性及其对IFN-α100U/ml、500U/ml及IFN-γ500U/ml预处理4小时后的反应。结果显示,病人PBL NK,ADCC活性与正常对照有显著差别,经IFNs处理后,其NK或/和ADCC活性均有不同程度的升高反应,从而提示了IFNs在慢性肝病治疗中的重要作用。     

树突状细胞上调MHC Ⅰ类相关抗原A表达对NK细胞活性的影响

目的:观察单核细胞、未成熟和成熟树突状细胞(DCs)表达MHC Ⅰ类相关抗原A(MICA)的情况,以及DCs表达MICA后对NK细胞活性的影响.方法:用流式细胞术分别检测单核细胞、未成熟DC(iDCs)以及LPS、TNF-α、CD40L、IL-15和IFN-α分别刺激的成熟DCs表面MICA的表达,并观察DCs表达MICA后对NK细胞表达CD69、细胞毒活性和分泌IFN-γ的影响.最后用流式细胞术检测重组NKG2D/Fc蛋白和抗IL-12单克隆抗体(mAb)对DCs激活NK细胞的影响.结果:单核细胞不表达MICA,iDCs低表达MICA.LPS、TNF-α和CD40L对DCs表达MICA无影响;但IFN-α和IL-15可促进DC上调MICA表达.DCs表达MICA后可促进NK细胞表达CD69、分泌IFN-γ、杀伤K562细胞.NKG2D/Fe蛋白可抑制NK细胞的杀伤活性和分泌IFN-γ;而抗IL-12mAb仅抑制IFN-γ分泌.结论:MICA在DCs表面的表达受局部微环境影响,且DCs表达MICA后可增强NK细胞的活性.     

调节性T细胞对NK细胞体外杀伤乳腺癌细胞的影响

目的探讨调节性T细胞(Regulatory T cells,T-reg细胞)对NK细胞的影响及可能机制。方法流式细胞术(Flowcytometry,FCM)检测乳腺癌患者外周血中T-reg细胞、NK细胞以及T细胞亚群比例。乳酸脱氢酶(Lactate dehydrogenase,LDH)法检测NK细胞对四种乳腺癌细胞株杀伤活性。ELISA检测上清液中IFN-γ和TGF-β1含量。结果乳腺癌和健康人外周血T-reg细胞分别占CD4~+T细胞的(7.5±3.0)%和(5.1±1.5)%(P<0.01=。T-reg细胞能抑制NK细胞杀伤乳腺癌细胞,同时下调NK细胞分泌IFN-γ,上清液中TGF-β1含量随着T-reg细胞比例的增高而增加。结论T-reg细胞抑制NK细胞杀伤乳腺癌的作用,其机制与T-reg细胞分泌细胞因子TGF-β1有一定关系。     

卵巢癌患者一线化疗后CD8~+T细胞和NK细胞数量及功能动态变化的研究

目的:研究晚期卵巢癌患者经一线化疗后体内CD8+T细胞和NK细胞数量及功能的动态变化.方法:选取术后行紫杉醇联合卡铂化疗的晚期卵巢上皮癌患者共13例,采集化疗前(S_0)、化疗后5-7天(S_1)、化疗后12～14天(S_2)和化疗后25～28天(S_3)外周血,流式细胞术检测患者外周血中CD3~+、CD4~+、CD8~+和NK细胞的百分比及绝对数量.采用体外自体肿瘤细胞裂解物脉冲淋巴细胞共培养的方法检测不同时间点CD8~+T细胞IFN-γ的分泌功能,并以LDH释放法测定NK细胞对K562细胞的杀伤活性.结果:在一个完整的化疗周期中,CD3~+、CD4~+、CD8~+细胞的绝对数目均于S_1期降至最低点,且与S_0期分别都有显著性差异.与对照组相比,当体外给予自身肿瘤细胞裂解物刺激诱导培养后,在S_1、S_2和S_3期产生IFN-γ的CD8~+细胞比例均较对照组显著增加,且CD8~+IFN-γ~+细胞比例在S2期达到最高.NK细胞的绝对数目于S1期降至最低点,且与S0期有显著性差异,NK细胞的比例及杀伤活性在化疗前、后均无显著性差异.结论:卵巢癌患者于一线化疗后机体经历免疫重建的过程,该过程中CD8~+T细胞介导的免疫应答一过性增高,而NK细胞的杀伤活性无明显变化.化疗后免疫重建期可能是免疫治疗实施的最佳窗口期.     

子痫前期小鼠动物模型的NK细胞和细胞因子的变化

目的:探讨磷脂酰丝氨酸(PS)/磷脂酰胆碱(PC)诱导的先兆子痫模型小鼠中自然杀伤(NK)细胞在外周血、脾脏及子宫的数量及其表面受体的变化,同时了解外周血中的细胞因子(TGF-β、TNF-α和IFN-γ)的水平.方法:用磷脂酰丝氨酸(PS)/磷脂酰胆碱(PC)诱导小鼠出现先兆子痫(PE)样症状,流式细胞仪检测自然杀伤(NK)细胞在外周血、脾脏及子宫的数量和表面受体,酶联免疫法检测外周血中TGF-β、TNF-α和IFN-γ.结果:我们建立的PE样小鼠模型是成功的;与对照组相比,gd17.5时PS/PC组外周血和脾脏中NK细胞数目增加.gd11.5时子宫中NK细胞数目突然增加,随后逐渐降低,且在gd14.5和gd17.5时PS/PC组比对照组NK细胞数目明显减少.PS/PC组脾脏中表面受体CD122表达显著降低,而CD244、CD94及NKG2D均显著增加;子宫中所有表面受体显著降低.在gd11.5、gd14.5及gd17.5时,与对照组相比,PS/PC组外周血中TGF-β的表达水平显著增加;而TNF-α和IFN-γ表达的水平大多不发生明显变化.结论:PE可能与母胎界面处NK细胞的数量及表面受体改变有关.外周血中TGF-β的增加可能抑制子宫处NKG2D等NK细胞表面受体的表达.关于TNF-α和IFN-γ在PE样小鼠模型中的作用还需进一步研究.     

CpG-ODN活化人NK细胞的初步研究

目的：研究D型CpG-ODN对人免疫细胞的活化效应。方法：CpG-ODN体外刺激人外周血单个核细胞(PBMC)，ELBA检测培养液IFN-α及IFN-γ的含量；RT-PCR检测PBMC中TLR9的表达水平；MTF法观察活化的NK对K562的杀伤作用。结果：CpG-ODN有效诱导PBMC分泌IFN-α和IFN-γ，增强活化的NK细胞对K562细胞的杀伤作用，且能显著上调TLR9 mRNA的表达。结论：在TLR9的介导下，CpG-ODN能有效激活NK细胞，参与机体免疫调节。     

重组可溶性MHC Ⅰ类相关蛋白A对NK细胞生物学活性的影响

目的:研究体外重组可溶性MHC Ⅰ类相关蛋白A(sMICA)对NK细胞杀伤靶细胞活性、分泌IFN-γ、增殖和凋亡的影响.方法:将重组sMICA蛋白与人外周血NK细胞相互作用过夜后,流式细胞仪检测NK细胞杀伤K562靶细胞的能力;ELISA检测培养上清IFN-γ浓度;MTS/PMS法检测sMICA对NK细胞增殖的影响;给NK细胞标记Annexin V和碘化丙啶检测凋亡情况.结果:可溶性MICA抑制NK细胞杀伤K562细胞的活性,下调IFN-γ的分泌,却对NK细胞的增殖和凋亡没有影响.结论:肿瘤细胞表面脱落的sMICA抗原可通过抑制NK细胞活性而逃逸机体的免疫监视功能.     

基于PD-1/PD-L1表达影响探讨四君子汤对NK细胞及结肠癌作用的研究

目的:通过四君子汤探讨PD-1/PD-L1的表达对NK细胞活性、结肠癌细胞HCT116增殖的影响及作用机制.方法:①通过人外周血淋巴分离液分离出NK细胞,构建NK细胞:HCT116细胞=5:1的共培养模型,将经200 ng/ml IFN-γ处理的NK细胞设为IFN-γ组,200 ng/ml IL-2处理的NK细胞设为I...     

自然杀伤细胞活性与血清癌胚抗原关系的研究

作者应用ＬＤＨ释放法测定ＮＫ细胞活性、放射免疫法测量血清癌胚抗原，平行检测２０例正常健康者，４０例胃癌病人的ＮＫ细胞活性及血清ＣＥＡ，结果表明：胃癌病人术前ＮＫ细胞活性明显降低，血清ＣＥＡ明显增高，ＮＫ细胞活性与血清ＣＥＡ呈显著负相关关系，作者推测血清ＣＥＡ可能对ＮＫ细胞活性有抑制作用。     

A Longitudinal Study of the Influence of Azathioprine on Natural Killer Cell Activity

Natural killer (NK) cell activity against K562 target cells was studied in six patients with definite or classical rheumatoid arthritis before and during treatment with azathioprine. Azathioprine induced suppression of NK cell activity, but treatment with azathioprine for 5-8 months was necessary before NK cell activity was completely suppressed. In vitro incubation of mononuclear cells from a healthy donor with azathioprine or 6-mercaptopurine in concentrations not reducing cell viability did not inhibit NK cell activity, nor did sera from patients treated with azathioprine for more than 6 months.     

Post-thymectomy Murine Experimental Autoimmune Oophoritis Is Associated With Reduced Natural Killer Cell Activity

PROBLEM: Natural killer (NK) cells can influence the immune response by secreting potent lymphokines. It has been suggested that NK cells have a suppressive action on B cells, and that impaired NK cell activity may play a role in some types of autoimmunity. NK cell abnormalities have been reported in women with premature ovarian failure. We therefore examined NK cell activity during the development of murine experimental autoimmune oophoritis, which serves as a model for autoimmune ovarian failure in women. METHOD OF STUDY: Neonatally thymectomized and sham-operated C57B1/6 × A/J (B6A) mice were prepared and sacrificed at 4, 6, 8, and 10 weeks after surgery. Splenic NK cell activity was determined in groups of five or more mice by measuring the percent specific lysis of target YAC-1 lymphoma cells using a standard 4-hr chromium release cytotoxicity assay. The number of splenic NK cells in neonatally thymectomized and sham-operated animals was also compared using flow cytometry. In a subsequent experiment, interleukin 12 (IL-12; NK cell-stimulating factor) was administered to neonatal mice before neonatal thymectomy. RESULTS: Neonatally thymectomized mice with associated autoimmune oophoritis had a 75% reduction in the number of splenic NK cells, and 50% or greater reduction in splenic NK cell activity at 4, 6, and 8 weeks after surgery. IL-12 treatment before neonatal thymectomy maintained NK cell activity and was shown to ameliorate the associated autoimmune oophoritis. CONCLUSION: Murine post-thymectomy autoimmune oophoritis is associated with reduced NK cell number and impaired NK cell activity, and in these respects the model is similar to premature ovarian failure in women. Research to define the relationship between NK cell abnormalities and the mechanism of ovarian failure in this model might lend insight into the pathogenesis of premature ovarian failure in women.     

Characterization of the in vivo and in vitro Effects of Indomethacin on Human Natural Killer Cell Activity

The in vivo and in vitro effects of indomethacin on the natural killer (NK) cell activity against K 562 target cells were studied. In vivo administration of indomethacin, 3 X 50 mg for 7 days to normal donors did not influence baseline NK cell activity, which means that treatment with prostaglandin (PG) inhibitors can be allowed in studies on NK cell activity of persons with normal PG production. The NK cell activity of fresh mononuclear cells was boosted with pharmacological concentrations of indomethacin in vitro, while frozen cells were not. Our results indicate that indomethacin enhances the NK cell activity in vitro by blocking the prostaglandin production of monocytes, since monocyte depleted effector cells were not boosted by indomethacin.     

Up-regulation of natural killer cell cytotoxicity by interleukin-2: the effect of sex and parity.

PROBLEM: Peripheral blood lymphocytes (PBLs) from some, but not all, female donors showed increased cytotoxicity in response to interleukin (IL)-2. METHOD OF STUDY: The effect of IL-2 on natural killer (NK) cell cytotoxicity was compared in nulliparous females, parous females, and males. Peripheral blood lymphocytes were preincubated for 20 or 72 hr with 5 or 100 U/ml IL-2 and cytotoxicity against K562 targets was then examined. RESULTS: In the parous females, only the 72-hr preincubation with 100 U/ml IL-2 significantly increased NK cell cytotoxicity, whereas nulliparous females also showed significantly increased cytotoxicity after a 20-hr preincubation with 100 U/ml IL-2. Neither female subject group had increased activity after preincubation for 20 or 72 hr with 5 U/ml IL-2. However, male peripheral blood lymphocytes also showed a significant increase in NK cell cytotoxicity when preincubated for 72 hr with 5 U/ml IL-2. CONCLUSIONS: The effect of IL-2 on NK cell cytotoxic activity may be related to sex and the state of parity.     

Suppression of Natural Killer Cell Activity by Monocytes Following Immunotherapy for Recurrent Spontaneous Aborters

PROBLEM : Natural killer (NK) cell activity has previously been shown to decrease in normal pregnancy as compared with the nonpregnancy state. The purpose of this study was to determine NK cell activity in recurrent aborters and to investigate the kinetics of NK cell activity following immunotherapy. METHODS : Recurrent aborters (N = 17) were immunized with husbands' mononuclear cells (1 × 10⁸) twice during the early stage of current pregnancy. NK cell activity of recurrent aborters as well as that of normal pregnant (N = 12) and nonpregnant (N = 6) women (controls) was determined by ⁵¹Cr release assay. Monocytes were depleted from the mononuclear cell fraction and its effect on the NK cell activity was determined as well. RESULTS : At around 5 wk of gestation, NK cell activity in recurrent aborters before treatment was significantly higher (28.0 ± 5.1%) than that in normal pregnancy (18.9 ± 4.3%) (P < 0.01). Following immunotherapy, NK cell activity of recurrent aborters (N = 13) who maintained their pregnancy decreased significantly (21.7 ± 8.9%) (P < 0.05). In contrast, NK cell activity of recurrent aborters (N = 4) who aborted their current pregnancy did not decrease. Depletion of monocytes resulted in a significant increase in NK cell activity (P < 0.05). CONCLUSIONS : This study suggests that the immunotherapy induces suppression of NK cell activity which may contribute for the maintenance of pregnancy. Moreover, monocytes may be involved in this suppression.     

Natural killer cell activity in families of patients with systemic lupus erythematosus: demonstration of a killing defect in patients

Natural killer (NK) cell cytotoxic activity and cell frequency, expressed as a percentage of total lymphocytes, have been determined in peripheral blood mononuclear cells from first-degree relatives of patients with systemic lupus erythematosus (SLE), the patients themselves, a group of rheumatoid arthritis (RA) patients and controls. Low levels of killing activity relative to controls were found in some members of all groups with the extent of depression falling into two ranges. Moderate reductions were seen in female (3/31, 10%) and male (4/14, 29%) relatives of SLE patients, female (12/60, 20%) and male (3/4, 75%) SLE patients and female RA patients (6/17, 35%). A more profound depression of killing activity was confined to other female SLE patients (15/60, 25%). There were strong correlations in all groups between killing activity and percentage of NK cells, but analysis of the ratio of these parameters and studies with purified preparations of NK cells suggest that the reduced activity in SLE frequently involves a defect in the killing capacity of the individual cells in addition to the reduced levels of NK cells. Azathioprine (AZA), which was used in treatment of 12 SLE patients, was invariably associated with low values of killing activity. It appears to substantially reduce the percentage of NK and B cells in an action unconnected with the NK cell abnormalities associated with SLE. The finding of low killing activity in relatives and a correlation between their activity and that of their patients support the view that NK cell deficiency is a genetic determinant of SLE. NK cells in SLE may produce insufficient levels of cytokines required for the regulation of IgG production.     

Natural Killer Cell Activity in Multiple Sclerosis and Myasthenia Gravis

Because of the potential role of Natural Killer (NK) cells in viral immunity and immunoregulation, we have undertaken a study of NK activity of peripheral blood lymphocytes from both Multiple Sclerosis (MS) and Myasthenia Gravis (MG) patients, two chronic diseases in which a viral etiology and an induced autoregulatory abnormality are strongly implicated. No significant difference between the mean NK activity in MS patients and controls was observed. A difference was observed between the NK activity of female MG patients and female controls, but no difference was seen between male MG patients and controls.     

Characterization of the in Vitro Effects of Glucocorticosteroids on NK Cell Activity

The NK cell activity of mononuclear cells as well as monocyte-depleted, Percoll-fractionated, NK cell-enriched effector cells against K 562 target cells was inhibited by methylprednisolone (MP) and hydrocortisone (HC) in a dose-dependent manner. The effector/target cell conjugate formation was studied in a single cell agarose assay, and it was shown that MP and HC partly inhibited the NK cell activity by inhibition of the adhesion of effector cells to target.     

绒毛膜促性腺激素对NK细胞活性的影响

为探讨绒毛膜促性腺激素 (HCG)对NK细胞活性的影响及其作用的机理 ,将健康人外周血单核细胞(+PBMC组 )及去除单核细胞的 (-PBMC组 )分别与HCG共同孵育后 ,以改良的MTT法检测NK细胞对其靶细胞K5 6 2 的杀伤活性。结果表明 :(1 )一定剂量 (2 5、50、1 0 0IU/mL)的HCG能显著抑制NK细胞的杀伤活性 ,其中以 50IU/mL的HCG作用最明显 ,而较低剂量 (1 2 .5IU/mL)和较高剂量 (2 0 0IU/mL)的HCG则无抑制作用。(2 )HCG对NK细胞的抑制作用通过单核细胞介导