自然流产患者蜕膜组织NK细胞受体表达分析

目的研究自然流产患者子宫蜕膜组织中NK细胞受体的表达格局。方法采用RT-PCR和免疫组织化学法检测了12例早期自然流产及40例同期正常早孕要求行人工流产者蜕膜组织的NK细胞受体表达水平。结果NK细胞受体中阳性最高的是KIR2DL4,流产组和对照组分别为100%和95%,其次是KIR2DL1,分别为83.3%和75%。ILT2和ILT4的阳性率较低,流产组和对照组分别为25%、30%和8.3%、10%。统计结果显示,KIR2DL4、KIR2DL1、ILT2和ILT4mRNA阳性率在早期自然流产病人组和对照组之间均无显著性差异。与对照组相比,早期自然流产病人的蜕膜组织中KIR2DL4分子的表达水平明显降低,具体表现在KIR2DL4的分布密度上。结论早期流产的发生与NK细胞受体的转录水平可能并无直接关联,但KIR2DL4分子的表达水平高低,可能对早期胚胎的生长、发育起关键作用。     

杀伤细胞免疫球蛋白样受体及其配体HLA-C基因多态性与不明原因早期复发性流产的相关性

目的:探讨杀伤细胞免疫球蛋白样受体及其配体HLA-C基因多态性与不明原因早期复发性流产易感性的关系。方法:留取不明原因早期复发性流产患者(38例,URSA组)及正常早孕妇女(35例,对照组)的蜕膜、绒毛组织,抽提基因组DNA,序列特异性引物聚合酶链反应检测蜕膜组织14种KIR基因的表达;DNA测序法分析绒毛滋养细胞HLA-C1、HLA-C2基因多态性。结果:14种KIR基因均以不同频率表达;KIR2DS1基因的频率在URSA组与对照组中分别为60.27%vs41.18%,两组相比,差异有显著性(P=0.03)。两组基因HLA-C1、HLA-C2在绒毛组织中呈不平衡表达,以HLA-C1基因占明显优势。URSA组与对照组HLA-C1基因频率分别为66.67%、81.03%,两组相比差异无显著性,P=0.657;URSA组HLA-C2的基因频率为33.33%,对照组HLA-C2的基因频率为19.07%,两组相比差异有显著性,P=0.007。结论:蜕膜NK细胞活化性KIR基因频率升高,与绒毛滋养细胞的HLA-C2基因结合,传递活化性信号活化NK细胞,可能是引起URSA发病的免疫遗传学因素之一。     

杀伤细胞免疫球蛋白样受体基因多态性与不明原因复发性早期自然流产的关联性研究

目的探讨杀伤细胞免疫球蛋白样受体（killer cell immunoglobulin-like receptor，KIR）基因多态性与不明原因的复发性早期自然流产的关联性。方法采用序列特异性引物聚合酶链反应（PCR-SSP）法，分析我院就诊的100例不明原因的复发性早期自然流产（unexplained recurrent spontaneous abortions，URSA）患者和112例无血缘关系的正常妇女KIR基因位点的多态性。结果URSA病例组KIR2DS1（P=0．003）、KIR2DS2（P=0．008）、KIR2DL5（P=0．003）基因的阳性率较随机对照组显著升高，URSA病例组活化性KIR基因数目较对照组显著增多（P=0．002）。具有3个或3个以下活化性KIR基因的个体在病例组中占40．00％，在对照组中占58．04％；而具有3个以上活化性KIR基因的个体在病例组中占60．00％，在对照组中占41．96％，两者差异具有统计学意义（P=0．009）。结论活化性KIR基因数目增多可能参与不明原因复发性早期自然流产的发病。KIR2DS1、KIR2DS2、KIR2DL5基因频率升高可能是不明原因复发性早期自然流产的原因之一。     

孕酮及其受体、IL-8与原因不明自然流产的相关性研究

目的：探讨孕酮（P）及其受体（PR）、IL-8在原因不明自然流产患者外周血及母胎界面的表达及相关性。方法：ELISA检测30例原因不明自然流产患者（流产组）和30例正常妊娠妇女（对照组）血清P、IL-8水平,免疫组织化学染色法检测两组流产绒毛和蜕膜组织PR、IL-8表达。结果：流产组血清P水平明显低于对照组（P<0.01）,血清IL-8水平明显高于对照组（P<0.01）。两组绒毛组织PR蛋白表达均为阴性;两组蜕膜组织中PR均表达于蜕膜细胞的细胞核,且流产组表达明显低于对照组（P<0.01）。两组绒毛组织中IL-8均表达于绒毛上皮细胞的细胞质,且流产组表达明显高于对照组（P<0.01）;两组蜕膜组织中IL-8均表达于蜕膜细胞的细胞质,且流产组表达高于对照组（P<0.05）。流产组血清P与IL-8呈显著负相关（r=-0.870,P<0.01）,流产组蜕膜组织PR与IL-8呈显著负相关（r=-0.650,P<0.01）。结论：P、PR低表达、IL-8高表达可能与原因不明自然流产发生相关,且P、PR可能通过下调IL-8表达维持正常妊娠。     

NK细胞受体与配体的特异识别

NK细胞通过其表面活化型受体和抑制型受体与相应配体特异识别,启动一系列信号转导,并且各种信号的整合效应决定着NK细胞是发挥效应功能,还是处于抑制状态。研究NK细胞受体与配体的特异识别中起重要作用的受体的结构、功能、配体特异性以及这一特异识别在病毒感染、肿瘤及自身免疫性疾病中所扮演的角色有重要意义。     

不明原因习惯性流产妇女外周血、蜕膜和绒毛组织TNF-a表达

免疫因素在不明原因习惯性流产(recurrent spontaneous abortion,RSA)妇女中的致病作用已逐渐被学者认知,外周血、蜕膜和绒毛组织都是孕早期母体和胚胎最直接接触部分,在孕早期这些位置的免疫细胞数量、活性及其所分泌细胞因子对维持正常妊娠扮演着至关重要角色,肿瘤坏死因子-α(TINF-a)是其中较重要细胞因子之一.我们观察了25例育龄期RSA妇女外周血、蜕膜和绒毛组织中TNF-α表达变化,并与同期正常怀孕后人工流产妇女相同检测结果比较,报道如下.     

NK细胞表面活化性受体的研究进展

NK细胞识别“自己”和“非己”的能力由NK细胞表面活化性受体传导的活化信号与抑制性受体传导的抑制信号之间的平衡来决定,对NK细胞活化性受体及其配体、信号传导路径的深入研究将为自然杀伤细胞的免疫疗法提供有效途径。     

CXCR2在不明原因自然流产患者绒毛和蜕膜组织中的表达

目的研究CXCR2在不明原因自然流产患者绒毛及蜕膜组织中的表达情况。方法应用免疫组织化学染色和图像分析技术,观察CXCR2在不明原因自然流产患者（病例组）和正常人工流产者（对照组）绒毛及蜕膜组织中的表达情况;HE染色后光镜下观察不明原因自然流产患者绒毛与蜕膜组织的形态学变化。结果免疫组化染色结果显示：两组CXCR2蛋白主要表达于绒毛的滋养层、蜕膜组织中的腺体,病例组绒毛滋养层和腺体CXCR2蛋白表达均强于对照组,两组比较,有显著性差异（P〈0.01）。病例组蜕膜细胞CXCR2蛋白呈阳性表达,对照组呈阴性;HE染色可见不明原因自然流产患者绒毛组织的滋养层变薄、滋养层细胞变性甚至坏死、滋养层嗜酸性增强、绒毛中轴纤维化程度增强;蜕膜组织中蜕膜细胞连接松散、蜕膜细胞空泡化、蜕膜组织中有大量炎细胞浸润。结论 CXCR2可能通过与其配体白细胞介素-8结合而参与不明原因自然流产的病理过程。     

不明原因习惯性流产妇女外周血、蜕膜和绒毛组织TNF-ɑ表达

免疫因素在不明原因习惯性流产(recurrent spontaneous abortion,RSA)妇女中的致病作用已逐渐被学者认知,外周血、蜕膜和绒毛组织都是孕早期母体和胚胎最直接接触部分,在孕早期这些位置的免疫细胞数量、活性及其所分泌细胞因子对维持正常妊娠扮演着至关重要角色,肿瘤坏死因子-浕(TNF-浕)是其中较重要细胞因子之一。     

自然流产患者外周血与蜕膜NK细胞亚群数量变化的研究

目的：研究自然流产患者外周血与蜕膜组织自然杀伤细胞亚群数量的变化。方法：对36例自然流产患者及30例正常健康早孕者（对照）外周血及蜕膜组织中淋巴细胞进行单克隆抗体标记,应用流式细胞仪定性、定量分析技术对NK细胞（natural killer)亚群进行分析。结果：（1）流产组外周血及蜕膜组织NK细胞CD56＋CD16＋百分比较对照组明显升高。（P＜0．01）,而蜕膜组织中NK细胞CD56＋CD16－百分比明显低于对照组（P＜0．001）。（2）外周血与蜕膜组织NK细胞CD56＋CD16＋亚群存在相关性（γ＝0．516,P＜0．05）。结论：NK细胞亚群的数量变化可以引起蜕膜免疫微环境的失调,导致自然流产。外周血与蜕膜NK细胞CD56＋CD16＋亚群存在正相关关系。     

Role of decidual natural killer (NK) cells in patients with missed abortion: differences between cases with normal and abnormal chromosome.

In order to study the mechanism of abortion, the proportions of NK cells in the peripheral blood and decidual lymphocytes were evaluated in both chromosomally normal and abnormal missed abortions. In normal pregnancy, CD56+16-3- NK cells are a major element of decidual lymphocytes. The percentages of CD56+16-3-NK cells of peripheral lymphocytes in normal pregnancies were not statistically significantly different from those of chromosomally normal and abnormal abortions. In the decidua, the percentages of CD56+16-3- NK cells of decidual lymphocytes showed no statistically significant differences between normal pregnancies and chromosomally abnormal abortions. However, the percentages of CD56+16-3-NK cells of chromosomally normal abortions were lower than those of chromosomally abnormal (P = 0.0025). Moreover, the percentages of CD56+16- NK cells in abortions with normal chromosomes were lower than those in normal pregnancies or abortions with abnormal chromosomes (P = 0.0037, P = 0.0025). However, when the proportion of CD56+ NK cells expressing CD16 was evaluated, there were no statistically significant differences in the percentages of CD56+16+ NK cells in normal pregnancies and missed abortions with normal chromosomes and abnormal chromosomes. We conclude that the expression of decidual CD56+16-3- NK cells in missed abortions with normal chromosomes is different from abortions with abnormal chromosomes and that this phenomenon may depend on an abnormal immune response of the maternal side.     

Increased natural killer cell cytotoxicity and IL-2 production in recurrent spontaneous abortion

PROBLEM: To determine whether natural killer (NK) cells cytotoxicity in peripheral blood is altered in patients with a history of recurrent spontaneous abortion (RSA); also, if there is any correlation between cytokine production and NK cytotoxicity. METHOD OF STUDY: In this case-control study, 21 patients with RSA within 24 hr of the last abortion (group I), and 32 pregnants with no history of abortion (group II) were surveyed. NK cell cytotoxicity was evaluated by flow cytometry, and IL-2, IL-10, transforming growth factor beta1 were measured in cell culture supernatant by ELISA method. RESULTS: Group I showed higher NK cytotoxicity than group II at all of effector to target (E:T) ratios (P < or = 0.045).The correlation between production of IL-2 and NK cytotoxicity was positively significant (R = 0.350, P = 0.001). Group I had significantly higher levels of IL-2 than group II (P = 0.001). In group II, the production of IL-10 by peripheral blood mononuclear cells was higher than group I (P = 0.002). CONCLUSION: Increased NK cell cytotoxicity and high level of IL-2 may be considered as a risk factor for RSA.     

Natural killer (NK) cell receptors' repertoire in couples with recurrent spontaneous abortions

PROBLEM: Natural killer (NK) cell receptors (NKRs) have been suggested to protect trophoblast, but their function at the fetomaternal interface remains unknown. To investigate if the outcome of pregnancy depends on women's NKRs, we studied the NKR repertoire in couples with recurrent spontaneous abortions (RSA). METHODS: Twenty-six childless couples with > or = 2 abortions, characterized by alloimmune abnormalities, and 26 control couples were genotyped for five killer immunoglobulin-like receptors (KIR) and two CD94/NKG receptors, known to have as ligands human leukocyte antigen (HLA) class I molecules with trophoblastic expression: inhibitory 2DL1,2,3 and activating 2DS1,4 KIRs, inhibitory NKG2A and activating NKG2C. Detected repertoires of women and partners were compared between the two groups. RESULTS: Less aborters than controls were found to have all three inhibitory KIRs (30.77% versus 69.23%, P = 0.01), some of them had only one inhibitory KIR (19.23% versus 3.85%, P = 0.08) and most of them were lacking inhibitory KIRs possessed by their husbands (57.69% versus 15.38%, P = 0.001). CONCLUSIONS: Women with alloimmune abortions have a limited inhibiting KIR repertoire and such miscarriages may occur because trophoblastic HLA class I molecules are recognized by decidual NK cells lacking the appropriate inhibitory KIRs.     

Decrease in a specific killer cell immunoglobulin-like receptor on peripheral natural killer cells in women with recurrent spontaneous abortion of unexplained etiology

PROBLEM: The aim of this study was to investigate immunophenotypic characteristics of natural killer (NK) cells by assessing specific molecules expressed in women with recurrent spontaneous abortion (RSA) of unexplained etiology. METHOD OF STUDY: Peripheral blood cells were obtained from 20 RSA women and 15 fertile controls. The expression of perforin, CD94, CD161, CD158a, CD158b, and CD244 on CD3- CD56+ NK cells was analyzed by flow cytometry. RESULTS: A significant decrease in CD158a expression was demonstrated in RSA women (mean +/- SD, 22.9 +/- 8.7%) as compared with that in controls (33.6 +/- 15.7%) (P < 0.05). The percentage of NK cells showing dual expression of CD94 and CD161 was relatively higher in RSA women (55.1 +/- 10.2%) than in the controls (47.1 +/- 19.0%), but without statistically significant (P = 0.096). The expression of perforin, CD158b, or CD244 in RSA women did not differ from that in the controls. CONCLUSIONS: A divergence of the specific NK cell repertoire might be related to the etiology of RSA.     

Different natural killer (NK) receptor expression and immunoglobulin E (IgE) regulation by NK1 and NK2 cells

Many studies concerning the role of T cells and cytokines in allergy have been performed, but little is known about the role of natural killer (NK) cells. Accordingly, the expression of co-stimulatory, inhibitory and apoptosis receptors, cytokine profiles and their effect on immunoglobulin isotypes were investigated in polyallergic atopic dermatitis (AD) patients with hyper immunoglobulin E (IgE) and healthy individuals. AD patients showed significantly decreased peripheral blood NK cells compared to healthy individuals. Freshly isolated NK cells of polyallergic patients spontaneously released higher amounts of interleukin (IL)-4, IL-5, IL-13 and interferon (IFN)-gamma compared to healthy individuals. NK cells were differentiated to NK1 cells by IL-12 and neutralizing anti-IL-4 monoclonal antibodies (mAb), and to NK2 cells by IL-4 and neutralizing anti-IL-12 mAb. Following IL-12 stimulation, NK cells produced increased levels of IFN-gamma and decreased IL-4. In contrast, stimulation of NK cells with IL-4 inhibited IFN-gamma, but increased IL-13, production. The effect of NK cell subsets on IgE regulation was examined in co-cultures of in vitro differentiated NK cells with peripheral blood mononuclear cells (PBMC) or B cells. NK1 cells significantly inhibited IL-4- and soluble CD40-ligand-stimulated IgE production; however, NK2 cells did not have any effect. The inhibitory effect of NK1 cells on IgE production was blocked by neutralization of IFN-gamma. Except for CD40, NK cell subsets showed different expression of killer-inhibitory receptors and co-stimulatory molecules between the polyallergic and healthy subjects. These results indicate that human NK cells show differences in numbers, surface receptor and cytokine phenotypes and functional properties in AD.     

Expression of killer immunoglobulin-like receptors on peripheral blood NK cell subsets of women with recurrent spontaneous abortions or implantation failures

PROBLEM: Decidual natural killer (NK) cells express inhibitory receptors (killer immunoglobulin-like receptors, KIRs), which bind to ligands on trophoblast cells (human leucocyte antigen, HLA-C). This interaction appears to block NK cytotoxicity against trophoblast cells. In this study, we investigated the expression of inhibitory and activating receptors in peripheral blood NK cells of women with recurrent spontaneous abortion (RSA) or implantation failures. METHOD OF STUDY: CD56(dim)/CD16(+), CD56(bright)/CD16(-) NK cells and CD56(+)/CD3(+) NKT cells of women with RSA or in vitro fertilization (IVF) failures and normal controls were analyzed for the expression of CD158a, CD158b inhibitory KIRs or CD161-activating receptors, by flow cytometric analysis. RESULTS: CD158a and CD158b inhibitory receptor expression by CD56(dim)/CD16(+) and CD56(bright)/CD16(-) NK cells were significantly decreased, and CD161-activating receptor expression by CD56(+)/CD3(+) NKT cells was significantly increased in women with implantation failures when compared with normal controls. CONCLUSIONS: An imbalance between inhibitory and activating receptor expression was found in NK cells of women with implantation failures. This imbalance may explain the adverse reproductive outcome.     

Different expression of NOD2 in decidual stromal cells between normal and unexplained recurrent spontaneous abortion women during first trimester gestation

The NOD2 gene, encoding intracellular paternal recognition receptor (PRR) also called caspase activation and recruitment domain 15 (CARD15), is mutated in Crohn’s disease, an autoimmune-disorder. Unexplained recurrent spontaneous abortion (URSA) involved in complex auto-immune disorder. However, little is known about the expression of NOD2 protein at maternal-fetal interface with URSA patients. Our aim was to compare the expression levels of NOD2 in the decidual stromal cells (DSCs) from patients with normal pregnancy to those with unexplained recurrent spontaneous abortion (URSA) during first trimester pregnancy. Tissues and DSCs were collected from 12 patients with URSA and 26 patients with normal pregnancies that required abortion. DSCs in the normal pregnancy group showed significantly higher mRNA and protein levels of NOD2 than those isolated from the URSA group using real time PCR and in cell western. The appropriate expression of NOD2 in normal DSCs suggests that this protein may be required to sustain normal pregnancy.     

妊娠期uNK、pNK细胞NKG2A与NKG2D的表达及其生物学意义的研究

目的:研究妊娠期妇女子宫NK细胞(uNK细胞)与外周血NK细胞(pNK细胞)表面NKG2A和NKG2D及其相应配体的表达,探讨uNK细胞表面NKG2A和NKG2D的不平衡表达与母胎界面所形成的免疫耐受关系。方法:采用流式细胞术检测30例孕6～9周的正常妊娠妇女uNK细胞和pNK细胞NKG2A、NKG2D的表达状况;RTPCR技术检测绒毛膜组织HLAE、MICA的表达。结果:子宫NK细胞NKG2A的表达显著高于外周血NK细胞,二者分别为(97.86±1.75)%与(33.35±10.92)%;子宫NK细胞NKG2D的表达水平与外周血NK细胞相近,分别为(93.21±4.52)%与(97.80±1.72)%,滋养层组织仅检测到HLAEmRNA的表达。结论:妊娠期子宫NK细胞表面高表达抑制性受体NKG2A,同时滋养层组织表达相应的配体HLAE,这可能是维持母胎界面免疫耐受的重要因素。     

Lactoferrin-inducible monocyte cytotoxicity for K562 cells and decay of natural killer lymphocyte cytotoxicity.

Monocyte-enriched and lymphocyte-enriched fractions of peripheral blood from three healthy volunteers were obtained by percoll density gradient centrifugation. The cytotoxic activity of each fraction against 51Cr-labelled K562 cells was quantified in a 2-h assay using freshly isolated cells of each fraction and cells of each fraction which had been incubated with and without lactoferrin in complete medium for 18 h before performing the assay. We have thereby shown that cytotoxicity was not demonstrable in the lymphocyte fraction (containing 7.3 +/- 2% large granular lymphocytes) after 18 h in medium, whereas the cytotoxicity of the monocyte fraction (containing 3 +/- 0.4% large granular lymphocytes) was still significantly increased (P less than or equal to 0.01) and that lactoferrin had no effect on lymphocyte fraction cytotoxicity while producing an 11-fold increase in the cytotoxicity of the monocyte fraction. It is therefore possible to perform a relatively simple test of monocyte cytotoxicity using lactoferrin as a stimulant in a 2-h 51Cr-labelled K562 assay system by allowing 18 h to elapse for lymphocyte natural killer cytotoxicity to decay.