活化型受体NKG2D及其配体在肿瘤免疫中的作用

自然杀伤（NK）细胞和T细胞是主要的抗肿瘤免疫效应细胞,在肿瘤免疫监视中发挥着重要作用。近年来由于NKG2D及其配体的发现,对NK细胞抗肿瘤分子机制有了更进一步认识,从而为开发新的抗肿瘤免疫治疗开辟了新的道路。NKG2D不仅在所有的NK细胞上表达,     

活化性受体NKG2D免疫监视作用研究新进展

<正>近年来,人们对活化性受体NKG2D免疫监视作用有了新的认识,包括其配体为压力诱导型分子,在应激如感染,细胞变异等条件下诱导表达,这为临床肿瘤免疫治疗提供了一种新的疗法——NKG2D及其配体介导的肿瘤免疫治疗。     

肺癌患者MASP-2、NKG2D水平与病理生理特征的相关性

目的 探讨肺癌患者甘露糖结合凝集素相关丝氨酸蛋白酶2(mannanbinding lectin associated serine proteases-2,MASP-2)、自然杀伤细胞2D(natural killer cell 2D,NKG2D)水平与病理生理特征的相关性。方法 选择2018年8月—2021年4月河南省荣军医院的104例肺癌患者作为肺癌组,同时选择68名同期健康体检者作为对照组。比较两组研究对象MASP-2、NKG2D的表达水平,并分析肺癌组患者MASP-2、NKG2D表达水平与其病理特征的相关性。运用受试者工作特征曲线（receiver operating characteristic curve,ROC）分析MASP-2、NKG2D单独检测及联合检测对肺癌的诊断价值。结果 肺癌组MASP-2水平（424.55 vs. 221.48,P <0.001）显著高于对照组,而NKG2D水平（74.42 vs. 84.23,P <0.001）低于对照组。MASP-2、NKG2D水平在肺癌中呈中度相关（r=0.554,P <0.05）。MASP-2水平在非小...     

乳腺癌NKG2D表达及对NK细胞杀伤活性的影响

目的分析乳腺癌NKG2D表达及对NK细胞细胞毒的影响。方法应用免疫荧光技术和流式细胞术（FCM）分选25例乳腺癌、25例健康对照的外周血NK细胞,定量分析NKG2D蛋白表达。用MTT比色法检测抗NKG2DpAb加入前后NK细胞的细胞毒效应。结果乳腺癌患者NK细胞的NKG2D蛋白表达量均低于正常对照,差异有显著性（P〈0.05）。抗NKG2DpAb能显著抑制NK细胞对K562细胞的细胞毒效应。结论NK细胞NKG2D表达异常与乳腺癌的发生发展可能有关。     

阻断NKG2A共抑制分子在抗肿瘤免疫效应中的研究进展

自然杀伤(NK)细胞在对病毒的先天防御以及控制肿瘤生长和转移中发挥着重要作用,NK细胞的免疫效应是由其表面的激活性和抑制性受体所调控的.NKG2A是一种在NK细胞和细胞毒性T淋巴细胞(CD8+T)表面均表达的抑制性受体.在多种肿瘤研究中均发现肿瘤浸润淋巴细胞表面NKG2A表达上调及肿瘤细胞表面其配体人类白细胞抗原E(H...     

IL-15对CIK细胞的NKG2D表达及杀伤活性的影响

目的探索IL-15对CIK细胞NKG2D表达及对肿瘤细胞体外杀伤活性的影响。方法以常规培养的CIK细胞(常规组)为对照,流式细胞术(FCM)检测常规培养体系中加入IL-15后CIK细胞(IL-15组)的NKG2D表达情况;MTT法检测IL-15组及封闭NKG2D受体的CIK细胞对MDA-MB-231、SKBr-3等癌细胞的杀伤活性。结果①培养后的各个时段,IL-15组CIK细胞中T淋巴细胞亚群、CD3+CD56+细胞及总CIK细胞群的NKG2D表达水平高于常规组,两组的差异有统计学意义(P<0.05)。②培养14、21d的IL-15组CIK细胞对MDA-MB-231和SKBr-3的杀伤活性明显高于常规组,差异有统计学意义(P<0.05)。③NKG2D单抗可以下调CIK细胞对MDA-MB-231细胞的杀伤效应,而对SKBr-3细胞的杀伤没有明显影响。结论 IL-15可以增加CIK细胞NKG2D的表达水平并提高对肿瘤细胞的杀伤活性,NKG2D途径是CIK细胞杀伤肿瘤细胞的重要机制之一。     

EphB2受体及其配体在肿瘤癌变中作用的研究进展

<正>肿瘤的发生及演变与细胞内信号转导异常有着密切的关系。其中酪氨酸蛋白激酶受体(receptor of tyrosine kinase,RTK)在信号传导中的作用尤为重要。Eph(erythropoietin-producing hepatoma cell line)家族是最大的酪氨酸蛋白激酶     

HPLC法测定维生素D2果糖酸钙注射液中维生素D2含量测定

目的建立检查维生素D2果糖酸钙中维生素D2的含量测定的高效液相色谱法。方法采用Thermo硅胶（5μm,4.6×250mm）色谱柱,流动相为正己烷-正戊醇（997∶3）,流速1.2mL·min-1,检测波长为254nm。结果维生素D2在0.4736μg·mL-1～4.262μg·mL-1范围内浓度和维生素D2与内标峰面积比呈良好的线性关系。平均回收率为103.2%（RSD=2.4%,n=9）。结论本文方法较为准确、快速,适合于维生素D2果糖酸钙中维生素D2的含量测定的质量控制。     

The NKG2D axis: an emerging target in cancer immunotherapy

Introduction: The immunoreceptor NKG2D belongs to the best-characterized activating receptors of cytotoxic lymphocytes. NKG2D binds to a variety of cell surface glycoproteins distantly related to MHC class I molecules, termed NKG2D ligands (NKG2DL). NKG2DL are inducibly expressed upon cellular stress, viral infection or malignant transformation thus marking ‘stressed’ or ‘harmful’ cells for clearance through NKG2D⁺ lymphocytes. However, certain viruses and many tumors employ various strategies to escape from NKG2D-mediated immunosurveillance.

Areas covered: Expression and regulation of both NKG2D and NKG2DL, especially at sites of immune responses or in the tumor microenvironment, as well as mechanisms of NKG2D escape strategies, as their understanding is key for harnessing the NKG2D/NKG2DL axis for immunotherapy. Studies documenting the importance of the NKG2D/NKG2DL axis for cancer immunosurveillance. Therapeutic approaches targeting the NKG2D/NKG2DL axis in cancer.

Expert opinion: The selective expression of NKG2DL on malignant cells together with the strong activating potency of NKG2D renders the NKG2D/NKG2DL axis a prime target for immunotherapies. Based on a thorough understanding of the NKG2D/NKG2DL system as well as of the most relevant escape strategies of tumors, the diligent and thoughtful design of novel treatment modalities harnessing the NKG2D/NKG2DL axis holds great promise for the future therapy of cancer.     

Decreased percentage of NKG2D+NK cells in patients with incident onset of Type 1 Diabetes

Type 1 diabetes mellitus (T1DM) is characterized by absolute insulin deficiency owing to autoimmune destruction of the pancreatic β cells. A significant decrease in natural killer (NK) cells in peripheral blood has been observed in patients with untreated T1DM. In the present study, we aimed to explore the role of NK cells and their subsets in young T1DM patients. A total of 30 children and adolescents with untreated T1DM and 27 healthy controls (HC) were recruited in this study. Flow cytometry analysis indicated that the percentage of peripheral blood CD3‐CD56+ NK cells and NK cells subsets (CD56bright, CD56dim and CD56neg), were significantly decreased in the T1DM patients compared to healthy controls. In addition, the percentage of inducible CD107a+ and IFN‐γ‐secreting NK cells was significantly decreased compared to HC. Interestingly, the percentage of NKG2D+ NK cells negatively correlated with the level of serum TCHOL and TG in T1DM patients. Our data indicate that decreased number and impaired function of NK cells may have a role in the pathogenesis of T1DM.     

Amphetamine Self-Administration Attenuates Dopamine D2 Autoreceptor Function

Dopamine D2 autoreceptors located on the midbrain dopaminergic neurons modulate dopamine (DA) neuron firing, DA release, and DA synthesis through a negative-feedback mechanism. Dysfunctional D2 autoreceptors following repeated drug exposure could lead to aberrant DA activity in the ventral tegmental area (VTA) and projection areas such as nucleus accumbens (NAcc), promoting drug-seeking and -taking behavior. Therefore, it is important to understand molecular mechanisms underlying drug-induced changes in D2 autoreceptors. Here, we reported that 5 days of amphetamine (AMPH) self-administration reduced the ability of D2 autoreceptors to inhibit DA release in the NAcc as determined by voltammetry. Using the antibody-capture [³⁵S]GTPγS scintillation proximity assay, we demonstrated for the first time that midbrain D2/D3 receptors were preferentially coupled to Gαi2, whereas striatal D2/D3 receptors were coupled equally to Gαi2 and Gαo for signaling. Importantly, AMPH abolished the interaction between Gαi2 and D2/D3 receptors in the midbrain while leaving striatal D2/D3 receptors unchanged. The disruption of the coupling between D2/D3 receptors and Gαi2 by AMPH is at least partially explained by the enhanced RGS2 (regulator of G-protein signaling 2) activity resulting from an increased RGS2 trafficking to the membrane. AMPH had no effects on the midbrain expression and trafficking of other RGS proteins such as RGS4 and RGS8. Our data suggest that midbrain D2/D3 receptors are more susceptible to AMPH-induced alterations. Reduced D2 autoreceptor function could lead to enhanced DA signaling and ultimately addiction-related behavior. RGS2 may be a potential non-dopaminergic target for pharmacological intervention of dysfunctional DA transmission and drug addiction.     

药物代谢酶细胞色素P450 2D6的遗传多态性研究进展

CYP2D6是肝脏中重要的药物代谢酶,其代谢的药物占临床应用药物的20%～25%.其遗传多态性对依赖CYP2D6代谢的药物具有重要的影响.本文综述了CYP2D6在遗传多态性方面的研究进展及其临床意义.     

The mechanism causing the difference in kinetic properties between rat CYP2D4 and human CYP2D6 in the oxidation of dextromethorphan and bufuralol

The capacity to oxidize bufuralol (BF) and dextromethorphan (DEX) was compared kinetically between human CYP2D6 and four rat CYP2D (CYP2D1, -2D2, -2D3 and -2D4) isoenzymes in a yeast cell expression system. In BF 1″-hydroxylation and DEX O-demethylation, only CYP2D4 showed hook-shaped Eadie-Hofstee plots, the other four CYP2D enzymes exhibiting linear plots. In DEX N-demethylation, rat CYP2D2 did not show any detectable activity under the conditions used, whereas the other four enzymes yielded linear Eadie-Hofstee plots. To elucidate the mechanisms causing the nonlinear kinetics, four CYP2D4 mutants, CYP2D4-F109I, -V123F, -L216F and -A486F, were prepared. CYP2D4-V123F, -L216F and -A486F yielded linear or linear-like Eadie-Hofstee plots for BF 1″-hydroxylation, whereas only CYP2D4-A486F exhibited linear plots for DEX O-demethylation. The substitution of Phe-109 by isoleucine did not have any effect on the oxidative capacity of CYP2D4 for either BF or DEX. These results suggest that the introduction of phenylalanine in the active-site cavity of CYP2D4 simplifies complicated interactions between the substrates and the amino acid residues, but the mechanisms causing the simplification differ between BF and DEX.     

CTLA-4 siRNA对慢性乙型肝炎患者外周血Th1/Th2细胞因子的影响

目的:观察化学合成的小干扰RNA(small interfering RNA,siRNA)对慢性乙型肝炎(chronic hepatitis B,CHB)患者外周血淋巴细胞细胞毒T淋巴细胞相关抗原4(cytotoxic T-lympho-cyte antigen 4,CTLA-4)表达的抑制作用及干扰后对细胞因子IFN-γ、IL-2和IL-4分泌的影响,探讨CTLA-4对慢性乙型肝炎的T细胞免疫调节作用。方法:检测CHB患者外周血淋巴细胞CTLA-4,观察其与HBV-DNA的相关性(P<0.05);根据人淋巴细胞CTLA-4的基因序列,设计合成CTLA-4 siRNA及阴性对照siRNA(siR-NA-co),电穿孔法转染CHB患者外周血淋巴细胞,采用实时荧光定量PCR(real-time Q-PCR)方法检测淋巴细胞CTLA-4 mRNA的表达,采用Western Blotting检测淋巴细胞CTLA-4蛋白表达,采用酶联免疫吸附试验(enzyme-linkedim-muno sorbent assay,ELISA)检测IFN-γ、IL-2和IL-4分泌。结果:CHB患者外周血淋巴细胞CTLA-4表达量与血清HBV-DNA载量有关;CTLA-4 siRNA转染CHB患者外周血淋巴细胞后,CTLA-4 mRNA及CTLA-4蛋白表达均受到抑制,IFN-γ、IL-2分泌增加,与阴性对照相比差异具有统计学意义(P<0.01)。而IL-4分泌没有变化,与阴性对照相比差异没有统计学意义(P>0.05)。结论:CHB患者外周血淋巴细胞CTLA-4表达一定程度抑制免疫反应,利于HBV-DNA的复制;利用siRNA在mRNA水平抑制CHB患者外周血淋巴细胞CTLA-4的表达,能够诱导Th1型细胞因子IL-2、IFN-γ分泌增加,对Th2型细胞因子IL-4无影响。说明抑制CTLA4有助于慢性乙型肝炎患者T细胞免疫的增强。     

四维超声在诊断胎儿畸形中的应用价值分析

目的探讨四维超声在诊断胎儿畸形中的应用价值情况。方法分析笔者所在医院收治的中晚期孕妇3000例临床资料,对比二维及四维超声检查胎儿畸形的结果。结果四维超声的胎儿畸形诊断率高于二维超声,四维超声检查可见20例胎儿畸形,其中唇裂6例,脊柱裂4例,无脑儿1例,脐膨出5例,胎儿心脏畸形2例,肛门闭锁1例,先天愚型1例。结论对于胎儿畸形诊断,四维超声可以全面、细致的观察胎儿发育异常,进而减少畸形胎儿出生率,提高人口生育质量,值得临床借鉴应用。