KIR在NK-92MI及K562细胞中的基因型及表达谱分析

目的:分析杀伤细胞免疫球蛋白样受体(KIR)在NK-92MI及K562细胞中的基因型及表达谱, 探索KIR受体的表达调控规律.方法:采用PCR、 RT-PCR及分子克隆测序技术, 检测K562及NK-92MI细胞中KIR2DL1、 2DL2、 2DL3、 2DL4、 2DL5、 2DS1、 2DS2、 2DS3、 2DS4、 2DS5、 3DL1、 3DL2、 3DL3、 3DS1、 2DP1、 3DP1的基因型, 及KIR2DL1、 KIR2DL2、 KIR2DL3、 KIR3DL1、 KIR2DS1、 KIR2DS3及KIR2DS2/4受体mRNA的表达.结果:K562细胞携带KIR2DL1、 2DL2、 2DL3、 2DL4、 2DL5A、 2DS2、 2DS4*003-006、 2DS5、 3DL1、 3DL2、 3DL3基因, 但不表达KIR.NK-92MI细胞携带KIR2DL1、 2DL2、 2DL3、 2DL4、 2DS2、 2DS4*001/002、 2DS4*003-006、 3DL1、 3DL2、 3DL3, 但只表达KIR2DL1、 KIR2DL3及KIR2DS2/4.结论:K562细胞及NK-92MI细胞均携带KIR2DL1、 2DL2、 2DL3、 2DL4、 2DS2、 2DS4*003-006、 3DL1、 3DL2、 3DL3.NK-92MI细胞表达KIR受体, K562细胞不表达上述KIR, KIR呈细胞特异性表达.     

启动子甲基化调控NK-92MI细胞KIR3DL1基因表达

目的:观察NK细胞系NK-92MI细胞中KIR3DL1基因启动子区的甲基化模式及去甲基化和组蛋白乙酰化对基因表达的影响,探讨KIR3DL1基因的表达调控机制.方法:采用亚硫酸氢盐测序法检测NK-92MI细胞中KIR3DL1基因启动子区的甲基化状况,应用甲基化抑制剂5-氮胞苷和(或)组蛋白去乙酰化转移酶抑制剂曲古抑菌素A处理NK-92MI细胞以诱导CpG岛去甲基化和组蛋白乙酰化,观察启动子区CpG岛甲基化和组蛋白乙酰化与KIR3DL1基因表达的关系.结果:NK-92MI细胞中KIR3DL1基因启动子区高甲基化,CpG二核苷酸甲基化频率在70%～100%之间;应用终浓度为2.5 μmol/L和5 μmol/L的5-氮胞苷作用72 h可以诱导NK-92MI细胞中KIR3DL1 mRNA表达量分别增加66.6%和114.6%;单用终浓度为50 nmol/L的曲古抑菌素A不能诱导NK-92MI细胞中KIR3DL1 mRNA表达量增加;此外,曲古抑菌素A和5-氮胞苷联用与单用5-氮胞苷相比也没有协同作用.结论:NK-92MI细胞中KIR3DL1基因表达受启动子甲基化调控.     

KIR2DL4在NK-92细胞上的超表达及其功能分析

目的 克隆KIR2DL4 cDNA，并使其在NK-92细胞上获得稳定表达，分析KIR2DL4分子对NK-92细胞功能的调节作用。方法 采用RT-PCR方法，从人蜕膜单个核细胞扩增出KIR2DL4 cDNA，将目的基因亚克隆于逆转录病毒表达载体构建成KIR2DL4-pLNCX表达载体，将重组质粒转入NK-92细胞，利用单克隆抗体#33进行FACS检测，观察KIR2DL4分子在靶细胞表面的表达。ELISA检测KIR2DL4对IFN-γ分泌的影响，同时根据LDH的释放实验，分析KIR2DL4分子对NK-92细胞毒功能的调节。结果：KIR2DL4分子在经KIR2DL4-pLNCX转染的靶细胞表面获得稳定高表达，且不影响其他受体在：NK-92细胞上的表达水平。KIR2DL4分子能够部分限制：NK-92细胞对HLA-G阳性靶细胞的杀伤作用，交联KIR2DL4分子能够诱导IFN-γ的分泌。结论 成功构建了KIR2DL4-pLNCX逆转录病毒表达载体，并使KIR2DL4分子在NK-92细胞上获得功能性的高表达。     

NK细胞可溶性KIR3DL1分子检测双夹心ELASA的建立

<正>自然杀伤细胞(natural killer cells,NK细胞)是固有免疫中一类十分重要的淋巴细胞,约占循环淋巴细胞总数的15%。目前根据CD56和CD16的表达水平可将NK细胞分为CD56hi、CD56dim和CD56-CD16+3个亚群。由于NK细胞不表达T细胞受体(T cell receptor,TCR)和B细胞受体(B cell receptor,BCR),如何区别"自己"和"非己"一直是个     

NK细胞受体KIR2DL4的结构与功能

KIR2DL4分子是NK细胞受体(NKR)的一种,属于免疫球蛋白样(IgSF)受体家族成员,主要分布在自然杀伤(Natural killer,NK)细胞上。KIR2DL4是HLA-G分子的特异性受体,结构上具备激活性和抑制性受体的双重特点,能够通过不同途径影响NK细胞的活性,具有重要的免疫调节功能。     

慢性乙型肝炎患者外周血CD8^＋ T细胞的KIR3DL1表达的探讨

目的：检测慢性乙型肝炎患者外周血CD8＋T细胞的KIR3DL1表达情况。方法：：采用流式细胞术检测慢性乙型肝炎患者外周血CD8＋T细胞的KIR3DL1分子表达,并与正常对照组比较。结果：慢性乙型肝炎患者外周血CD8＋T细胞的KIR3DL1分子表达明显高于对照组。结论：慢性乙型肝炎患者CD8＋T细胞的KIR3DL1表达显著增加。     

杀伤细胞免疫球蛋白样受体2DS4及其变体KIR1D与梅毒的关联性研究

目的 探讨杀伤细胞免疫球蛋白样受体(killer cell immunogloblin-like receptor,KIR)基因KIR2DS4及其变体KIR1D与属于KIR基因单体型A (haplotype A)的梅毒(syphilis)患者的关联性.方法 采用序列特异性引物聚合酶链反应(PCR-SSP)法,分析192例无血缘关系的健康人和190例梅毒患者KIR基因的单体型,在归类于单体型A的梅毒患者和健康人群中分析KIR2DS4和KIR1D基因与梅毒的关联.结果 在192例健康者中,含有KIR2DS4基因的个体为187例,其中有91例归类于纯合子(homozygous)单体型A,占48.7% (91/187);在190例梅毒患者中,出现KIR2DS4基因的个体为181例,其中有89例归类于纯合子单体型A,占49.2% (89/181).在归属于单体型A的人群中,KIR1D/KIR1D在梅毒病例组的基因型频率为16.9%,显著高于对照组(6.6%,P＝0.032),而KIR2DS4/KIR2DS4和KIR2DS4/KIR1D基因型频率在两组间差异均无统计学意义(P>0.05).结论 KIR1D/KIR1D可能与纯合子单体型A中的个体的梅毒发生相关联.

Abstract：

Objective To investigate the killer cell immunoglobulin-like receptor (KIR) genes, KIR2DS4 and its variant KIR1D for an association with syphilis in the comparison between syphilis patients and unrelated healthy subjects. Methods One hundred and ninety syphilis patients and 192 unrelated healthy subjects were performed to determine the KIR genotypes by PCR-SSP method. The gene frequencies of KIR2DS4 and KIR1D were analyzed for an association with syphilis in the patients and healthy people who belonged to KIR gene haplotype A. Results Of 192 healthy individuals, 187 were identified with a KIR2DS4 gene. And 91 individuals were classified as homozygous haplotype A with the percent of 48.7% (91/187) in 187 KIR2DS4 positive individuals. Of 190 syphilis patients, 181 were identified with a KIR2DS4 gene. And 89 individuals were classified as homozygous haplotype A with the percent of 49.2% (89/181) in 181 KIR2DS4 positive individuals. The frequency of KIR1D/KIR1D in syphilis patients classified as haplotype A was 16.9%, and was significantly higher than that in the control group (6.6%, P=0.032). However, there was no significant difference for the frequencies of KIR2DS4/KIR2DS4 and KIR2DS4/KIR1D between the two groups (P>0.05). Conclusion KIR1D/KIR1D might be associated with syphilis in the comparison between syphilis patients and unrelated healthy controls who were classified as homozygous haplotype A.     

NK-92细胞的研究和应用进展

恶性肿瘤是危害人类生命与健康的较为严重的常见病、多发病.针对肿瘤的治疗方法有多种,其中,肿瘤生物治疗中较成熟的是免疫细胞治疗,尤以树突状细胞(DC细胞)和过继性细胞(CIK细胞、LAK细胞、ANK细胞)治疗效果为最好[1].     

C型凝集素样自然杀伤(NK)细胞受体在结外鼻型NK/T细胞淋巴瘤中表达及意义

目的 探讨C型凝集素样自然杀伤(NK)细胞受体CD94和NKG2在结外鼻型NK/T细胞淋巴瘤中的表达及意义.方法 运用逆转录聚合酶链反应(RT-PCR)检测C型凝集素样NK细胞受体CD94和NKG2在经组织形态、免疫组织化学、EB病毒原位杂交及T细胞受体PCR克隆性重排分析确诊的21例结外鼻型NK/T细胞淋巴瘤以及对照组同部位B细胞淋巴瘤8例、淋巴结外周T细胞淋巴瘤(PTCL)10例、脾脏5例、胸腺5例和慢性炎性鼻黏膜5例组织中的表达情况并进行随访.结果 21例结外鼻型NK/T细胞淋巴瘤具有典型的形态学改变,表达CD3ε、CD56和细胞毒蛋白,TCR重排阴性,20例EB病毒阳性;RT-PCR扩增结果显示,在21例结外鼻型NK/T细胞淋巴瘤中,18例(85.7%)CD94呈阳性表达;NKG2总阳性率为95.2%(20/21),各亚基表达阳性率依次为NKG2A/2B(85.7%)、NKG2D(61.9%)、NKG2F(14.3%)、NKG2C,/2E(4.8%).对照组中PTCL和B细胞淋巴瘤均不表达CD94和NKG2,仅2例脾脏和2例慢性炎性鼻黏膜组织表达CD94,1例脾脏组织表达NKG2A/2B,1例胸腺组织表达NKG2D.CD94和NKG2在结外鼻型NK/T细胞淋巴瘤中的表达与T细胞淋巴瘤和B细胞淋巴瘤比较,差异均有统计学意义(P均<0.01).CD94和NKG2同时表达于17例结外鼻型NK/T细胞淋巴瘤,共表达率为81.0%(17/21).结论 CD94和NKG2在结外鼻型NK/T细胞淋巴瘤中呈特异性和顺序性表达,提示多数病例肿瘤细胞处于活化和功能NK细胞阶段.对这些分子的检测有可能成为NK细胞源性淋巴瘤诊断的重要手段.     

慢性乙型肝炎患者血清HBV DNA水平与细胞毒性T淋巴细胞表面PD-1表达的关系和意义

目的 探讨慢性乙型肝炎（CHB）患者血清HBV DNA水平与HBV特异性CTL表面程序性死亡受体-1（PD-1）表达的关系和意义.方法 将133例CHB患者根据血清HBV DNA水平分为甲、乙两组,甲组70例（52.63％）,HBV DNA水平为104～105拷贝/ml,乙组63例（47.37％）,HBVDNA水平分107 ～ 108拷贝/ml,对两组患者作HBV特异性CTL、非特异性CTL,HBV特异性CTL表面PD-1表达和肝功能的比较.结果 甲组HBV DNA水平为（5.03±1.01）log10拷贝/ml,低于乙组（7.59±0.99） log10拷贝/ml,t=11.23,P＜0.01,HBV特异性CTL表面PD-1表达（26.32±2.56）％,低于乙组（39.35 ±2.86）％,t=18.69,P＜0.01,HBV特异性CTL （0.37±0.02）％,高于乙组（0.22±0.02）％,t=25.80,P＜0.01,非特异性CTL（16.26 ±2.17）％,低于乙组（19.94±2.47）％,t=3.19,P＜0.01,ALT （259.16 ±85.11） U/L,低于乙组（501.16±86.15） U/L,t=15.10,P＜0.01,TBil（27.99±6.13）μmol/L,低于乙组（44.86±9.51） μmol/L,t=3.92,P＜0.01.结论 CHB患者HBV DNA水平低者,HBV特异性CTL表面PD-1表达也低,HBV特异性CTL水平高,HBV DNA水平高者,HBV特异性CTL表面PD-1表达也高,导致HBV特异性CTL水平降低,并启动非特异性CTL,引起肝功能损害加重.     

KIR2DL3 and KIR2DL1 show similar impact on licensing of human NK cells

Killer cell immunoglobulin‐like receptor/HLA class I (KIR/HLA‐I) combinations are associated with disease risk, implicating functional roles for NK cells (NKCs) or KIR⁺ T cells. KIR/HLA‐I interactions can act through inhibition of NKC activation by target cells and NKC licensing for greater intrinsic responsiveness. We compared licensing conferred by the weaker, HLA‐C group 1/KIR2DL3, and the stronger, HLA‐C group 2/KIR2DL1, inhibitory combinations. The “rheostat model” predicts weaker licensing by HLA‐C1/KIR2DL3 interactions than HLA‐C2/KIR2DL1. We analyzed degranulation in NKC subsets expressing single and multiple receptors for HLA‐I. NKG2A had the strongest licensing impact, while KIR2DL3, KIR2DL1, and KIR3DL1 were weaker, and not significantly different to each other. Presence of one or two matched HLA‐C allotypes did not alter licensing of KIR2DL3⁺ and KIR2DL1⁺ NKC. Coexpression of activating KIR2DS1 disarmed KIR2DL3⁺ and KIR2DL1⁺ NKC to a similar extent. KIR3DL1 and NKG2A combined for more enhanced licensing of double‐positive NKC than the combination of KIR2DL3 and KIR2DL1. Thus, KIR2DL3 and KIR2DL1 have similar capacity to license NKC, suggesting that inhibitory signal strength and amount of available HLA‐C ligands do not correlate with NKC licensing. Altogether, our results show that the basis for disease associations of HLA‐C and KIR2DL likely encompasses factors other than licensing.     

乙型肝炎病毒C蛋白对NK细胞功能影响的体外研究

目的 研究乙型肝炎病毒C蛋白在NK细胞中的表达及其对NK细胞功能的影响.方法 用脂质体转染法将HBV C基因真核表达载体pHBI-CMV-HBC转入NK-92细胞,通过WesternBlot检测C基因在NK-92细胞中表达,用ELISA法检测NK细胞分泌IFN-γ水平,MTT法检测NK细胞对HepG2细胞的细胞毒作用.结果 Western Blot证实转染有pHBI-CMV-HBC的NK-92细胞能表达HBV C蛋白.转染了重组真核表达质粒的NK-92细胞IFN-γ水平均高于空质粒对照组和空白对照组(P<0.01).与两对照组相比,重组真核表达质粒转染组NK-92细胞对于HepG2细胞的细胞毒活性明显提高,差异具有统计学意义(P<0.01).结论 HBc基因瞬时高表达可影响NK-92细胞分泌IFN-γ和细胞毒功能.     

Peptide selectivity discriminates NK cells from KIR2DL2‐ and KIR2DL3‐positive individuals

Natural killer cells are controlled by peptide selective inhibitory receptors for MHC class I, including the killer cell immunoglobulin‐like receptors (KIRs). Despite having similar ligands, KIR2DL2 and KIR2DL3 confer different levels of protection to infectious disease. To investigate how changes in peptide repertoire may differentially affect NK cell reactivity, NK cells from KIR2DL2 and KIR2DL3 homozygous donors were tested for activity against different combinations of strong inhibitory (VAPWNSFAL), weak inhibitory (VAPWNSRAL), and antagonist peptide (VAPWNSDAL). KIR2DL3‐positive NK cells were more sensitive to changes in the peptide content of MHC class I than KIR2DL2‐positive NK cells. These differences were observed for the weakly inhibitory peptide VAPWNSRAL in single peptide and double peptide experiments (p < 0.01 and p < 0.03, respectively). More significant differences were observed in experiments using all three peptides (p < 0.0001). Mathematical modeling of the experimental data demonstrated that VAPWNSRAL was dominant over VAPWNSFAL in distinguishing KIR2DL3‐ from KIR2DL2‐positive donors. Donors with different KIR genotypes have different responses to changes in the peptide bound by MHC class I. Differences in the response to the peptide content of MHC class I may be one mechanism underlying the protective effects of different KIR genes against infectious disease.     

The tortoise and the hare: slowly evolving T-cell responses take hastily evolving KIR

The killer cell immunoglobulin‐like receptor (KIR) locus comprises a variable and rapidly evolving set of genes encoding multiple inhibitory and activating receptors. The activating receptors recently evolved from the inhibitory receptors and both bind HLA class I and probably also class I‐like structures induced by viral infection. Although generally considered natural killer (NK) cell receptors, KIR are also expressed by a large fraction of effector memory T cells, which slowly accumulate during human life. These effector memory cells are functionally similar to NK cells, as they are immediate effector cells that are cytotoxic and produce IFN‐γ. However, different rules apply to NK and T cells with respect to KIR expression and function. For example, KIR tend to modulate signals driven by the T‐cell receptor (TCR) rather than to act independently, and use different signal transduction pathways to modulate only a subset of effector functions. The most important difference may lie in the rules governing tolerance: while NK cells with activating KIR binding self‐HLA are hyporesponsive, the same is unlikely to apply to T cells. We argue that the expression of activating KIR on virus‐specific T cells carrying TCR that weakly cross‐react with autoantigens can unleash the autoreactive potential of these cells. This may be the case in rheumatoid arthritis, where cytomegalovirus‐specific KIR2DS2⁺ T cells might cause vasculitis. Thus, the rapid evolution of activating KIR may have allowed for efficient NK‐cell control of viruses, but may also have increased the risk that slowly evolving T‐cell responses to persistent pathogens derail into autoimmunity.     

The differential impact of natural killer (NK) cell education via KIR2DL3 and KIR3DL1 on CCL4 secretion in the context of in‐vitro HIV infection

Carriage of certain inhibitory natural killer (NK) cell receptor (iNKR)/HLA ligand pairs is associated with protection from infection and slow time to AIDS implicating NK cells in HIV control. NK cells acquire functional potential through education, which requires the engagement of iNKRs by their human leucocyte antigen (HLA) ligands. HIV infection down‐regulates cell surface HLA‐A/B, but not HLA‐C/E. We investigated how NK cell populations expressing combinations of the iNKRs NKG2A, KIR2DL3 (2DL3) and KIR3DL1 (3DL1) responded to autologous HIV infected CD4 (iCD4) cells. Purified NK cells from HIV‐uninfected individuals were stimulated with autologous HIV iCD4 or uninfected CD4 T cells. Using flow cytometry we gated on each of the 8 NKG2A^+/–2DL3^+/–3DL1^+/‐ populations and analysed all possible combinations of interferon (IFN)‐γ, CCL4 and CD107a functional subsets responding to iCD4 cells. Infected CD4 cells induced differential frequencies of NKG2A^+/–2DL3^+/–3DL1^+/– populations with total IFN‐γ⁺, CCL4⁺ and CD107a⁺ functional profiles. 2DL3⁺NKG2A⁺ NK cells had a higher frequency of responses to iCD4 than other populations studied. A higher frequency of 2DL3⁺ NK cells responded to iCD4 from individuals that were not HLA‐C1 homozygotes. These results show that 2DL3⁺ NK cells are mediators of HIV‐specific responses. Furthermore, responses of NK cell populations to iCD4 are influenced not only by NK cell education through specific KIR/HLA pairs, but also by differential HIV‐mediated changes in HLA expression.     

Hematopoietic stem cell transplantation: Improving alloreactive Bw4 donor selection by genotyping codon 86 of KIR3DL1/S1

KIR3DL1 is a natural killer (NK) cell receptor that recognizes the Bw4 epitope of human leukocyte antigen (HLA) class I molecules. Following hematopoietic stem cell transplantation for patients lacking Bw4, KIR3DL1‐expressing NK cells from Bw4‐positive donors can be alloreactive and eliminate tumor cells. However, KIR3DL1 alleles having T instead of C at nucleotide 320 (encoding leucine 86 instead of serine 86) are not expressed on the cell surface. Thus, not all individuals testing positive for KIR3DL1 are optimal donors for Bw4‐negative recipients. Therefore, we developed a method for genotyping codon 86, which was validated by its perfect correlation with NK cell phenotype for 100 donors of diverse KIR3DL1/S1 genotype. We typed 600 donors and found that ～12.2% had the KIR3DL1 gene, but did not express cell‐surface KIR3DL1. By contrast, high‐expressing allotypes were identified when haplotypes from four families with duplicated KIR3DL1/S1 genes were characterized at high resolution. Identifying donors who have KIR3DL1 but lack cell‐surface KIR3DL1 would refine donor selection. With this technique, the number of individuals identified who may not be optimal donors for Bw4‐negative patients increases by threefold, when compared with standard methods. Taken together, we propose that allele typing of killer cell Ig‐like receptor (KIR) polymorphisms should become a standard practice when selecting donors.     

Influence of KIR gene diversity on the course of HSV-1 infection: resistance to the disease is associated with the absence of KIR2DL2 and KIR2DS2

Herpes simplex virus type 1 (HSV-1) causes lifelong latent infections in most humans. Periodical virus reactivations from latency in the neurons of sensitive ganglia lead to transport to mucocutaneous regions and productive replication, which results in recurrent inflammatory herpetic lesions or in asymptomatic virus shedding. The medical consequences of such lesions and the frequency of recurrences vary greatly in different subjects. Furthermore, many infected individuals never suffer manifestations of the disease, even when exposed to stimuli that trigger clinical recurrences in other humans. The origin of the variability in the clinical course of HSV-1 infection remains unexplained. Herpesviruses and other pathogens sabotage the expression of major histocompatibility complex class I molecules by infected cells, thus subverting T-cell-mediated immunity. Subversion of antigen presentation is counteracted by natural killer cells, which survey the human leukocyte antigen (HLA) expression by specific receptors. These include the killer cell immunoglobulin-like receptors (KIRs), which are encoded by a complex of extremely diverse and rapidly evolving genes. Here, we analyze the contribution of KIR gene diversity to the variable clinical course of HSV-1 infection by comparing the distribution of these genes in humans with clinical manifestations of the disease with that in asymptomatically infected donors. This study provides preliminary evidence that the receptors KIR2DL2 and KIR2DS2 predispose to symptomatic HSV-1 infection and favor the frequently recurring forms of the disease. Possible contribution of the 'HLA-C1' ligand to HSV-1 disease was not statistically supported. Because of an absolute genetic linkage between KIR2DL2 and KIR2DS2, we could not determine which receptor was primarily responsible for the observed association, but our results suggest that presence in the genome of KIR2DL2 and KIR2DS2 hinders an effective cellular response to HSV-1.