NKT细胞在抗肿瘤免疫中的作用及其机制

NKT细胞是免疫细胞中一类具有NK细胞特定标志的T细胞亚群,经活化,既可直接作为抗肿瘤效应细胞发挥杀伤作用,又能通过激活其他免疫效应细胞,如NK细胞,间接实现抗肿瘤作用。NKT细胞在抗肿瘤免疫、获得性免疫应答及免疫调节中起着重要作用。     

肿瘤相关巨噬细胞极化的研究进展

肿瘤相关巨噬细胞是肿瘤组织局部浸润的巨噬细胞,在肿瘤组织微环境中,这些巨噬细胞发生M2型极化,从而发挥免疫抑制效应,促进肿瘤增殖。而M2型极化的肿瘤相关巨噬细胞也能够被再次诱导逆向极化形成具有抗肿瘤效应的M1型肿瘤相关巨噬细胞,激发机体产生特异性抗肿瘤免疫应答。促进肿瘤相关巨噬细胞M1型极化由此成为当前抗肿瘤免疫防治研究的热点。将对有关肿瘤相关巨噬细胞极化的新进展进行综述,为抗肿瘤免疫研究提供新的思路。     

沙门菌用于肿瘤生物治疗的研究进展

沙门菌(Salmonella)是用于抗肿瘤生物治疗很有前景的一种生物反应调节剂(biological response modifier, BRM)。鼠伤寒沙门菌(Salmonella typhimurium)是肿瘤生物治疗研究中最为常用的沙门菌之一。沙门菌可以在肿瘤细胞中定植,通过激活抗肿瘤免疫应答、诱导肿瘤细胞死亡等途径抑制肿瘤细胞的生长及转移。沙门菌可与其他抗肿瘤疗法联合使用,增强化疗药物的作用,也可作为抗肿瘤制剂的载体。现就沙门菌用于肿瘤的生物治疗作一概述。     

天然来源抗肿瘤化合物作用于MAPK通路的机制

天然来源抗肿瘤活性产物是抗肿瘤药物先导化合物的重要资源。促分裂原活化蛋白激酶(MAPK)通路是细胞内重要的信号转导系统,可以调节细胞的生长、凋亡、黏附、迁移等过程,继而影响肿瘤的发生、发展、侵袭、转移,是潜在的抗肿瘤药物作用靶点之一。本文将对天然来源化合物作用于MAPK信号通路的靶点分子及生物效应进行阐述,为肿瘤的化学预防及治疗提供启发。     

中医药干预癌症免疫逃逸的研究进展

免疫逃逸是指恶性肿瘤细胞通过免疫编辑过程后具备浸润、转移等恶性生物学行为,并逃脱免疫系统的监视和清除,最终促进恶性肿瘤病情发生发展的过程。除其他因素外,免疫细胞还积极影响肿瘤发展的每一步,决定了癌细胞在受威胁的微环境中生存的机会。一旦发现第一个癌细胞,抗肿瘤免疫机制就会被激活,并在原发肿瘤形成和转移过程中发挥作用。然而,免疫功能受损时,肿瘤细胞就会通过逃避或者阻挠免疫反应的机制来促进自身的增殖,就会导致肿瘤的持续性发展。而中医药干预癌症免疫逃逸机制需以“扶正”为基本原则,补益正气以治其本,增强免疫细胞对癌细胞的杀伤力,阻止癌症免疫逃逸,从而抑制癌症的发展。根据现有文献分析可知,目前通过免疫逃逸治疗癌症多用补益类药物,这可能是因为机体免疫调节功能与中医“扶正”观点相符合。因此,研究癌症免疫逃逸机制不仅能够提高治疗癌症的效率,而且通过对中医药的开发利用,能够延缓疾病的发展进程,更好的改善患者的生存质量。     

细菌DNA抗肿瘤免疫的实验研究

应用纯化提取的３种细菌染色体ＤＮＡ进行体内抗肿瘤免疫实验。结果表明，大肠埃希菌、铜绿假单胞菌和长双岐杆菌ＤＮＡ由于含有大量的非甲基化的ＣｐＧ二核苷酸为核心的序列（称为ＣｐＧ ｍｏｔｉｆ），均能诱导ＮＫ细胞和单核细胞的激活，从而起到抗肿瘤免疫的作用。为微生物ＤＮＡ制剂作为生物反应修饰剂（ＢＲＭ）应用于抗肿瘤免疫提供了科学依据。     

生物大分子的硫酸化修饰及其生物活性的研究进展

生物大分子经过硫酸化修饰后具有抗病毒、抗肿瘤、抗凝血和增强免疫功能等生物活性。本文就硫酸化生物大分子的制备方法和生物活性等进行了综述。     

壳聚糖及其衍生物抗肿瘤作用研究进展

壳聚糖为天然多糖甲壳素脱除部分乙酰基的产物,是自然界存在的唯一碱性多糖,无毒,可生物降解,具有免疫功能和良好的生物相容性。近年发现,壳聚糖具有抗肿瘤作用,却因其难溶于水及中性溶剂而影响其应用,壳聚糖衍生物改善了壳聚糖的这个缺点,也具有更广泛的药理作用。本文对壳聚糖及其壳聚糖衍生物在抗肿瘤方面的研究情况做了综述。     

膜型Tim-3分子促进荷瘤小鼠抗肿瘤免疫应答的研究

目的 研究膜型Tim-3分子对H22肝癌细胞生长的抑制效应,探讨膜型Tim-3分子对荷瘤小鼠免疫系统的影响.方法 以H22肝癌细胞接种于BALB/c小鼠大腿肌肉建立小鼠实体瘤模型,采用原位注射裸DNA的方法在小鼠体内表达膜型Tim-3进行基因治疗,观察Tim-3对肿瘤生长的抑制作用;采用RTPCR技术在肿瘤生长不同时期检测Tim-3对4-1BB、IFN-γ、galectin-9等免疫相关基因表达的影响;流式细胞术检测膜型Tim-3对脾细胞增殖活性及细胞毒活性的影响;观察Tim-3 ＋4-1 BBL协同抗肿瘤作用.结果 体内转染表达Tim-3对肿瘤的生长有明显的抑制作用.流式细胞术结果显示,在小鼠荷瘤早期,Tim-3可提高脾细胞在特异性抗原刺激下的增殖反应和对H22肿瘤细胞的细胞毒作用;Tim-3与4-1BBL协同作用时抗肿瘤作用更加明显.结论 膜型Tim-3可在免疫启动阶段作为正向免疫调节因子增强抗肿瘤免疫应答,并可与4-1 BBL协同产生更强的抑瘤效应.     

NKT细胞抑制或增强抗肿瘤免疫反应的机制

自然杀伤性T细胞是表达NK细胞表面标志的一类特殊T细胞,对免疫系统具有重要的调节功能.在抗肿瘤的免疫反应中表现抑制或增强的不同作用,该文介绍NKT细胞通过分泌IL-12激活效应细胞对抗肿瘤作用的分子机制;并阐释在动物模型中NKT细胞分泌IL-13调控STAT-6信号途径,下调免疫监视并抑制抗肿瘤的作用;以及目前提出的NKT细胞在抗肿瘤免疫中的协调作用机制.     

Investigation of the mechanism of temperature sensitivity of the electroreceptors of ampullae of lorenzini

In experiments on Black Sea skates (Raja clavata), the potential of the receptor epithelium of the ampullae of Lorenzini and spike activity of single nerve fibers connected to them were investigated during electrical and temperature stimulation. Usually the potential within the canal was between 0 and –2 mV, and the input resistance of the ampulla 250–400 k. Heating of the region of the receptor epithelium was accompanied by a negative wave of potential, an increase in input resistance, and inhibition of spike activity. With worsening of the animal's condition the transepithelial potential became positive (up to +10 mV) but the input resistance of the ampulla during stimulation with a positive current was nonlinear in some cases: a regenerative spike of positive polarity appeared in the channel. During heating, the spike response was sometimes reversed in sign. It is suggested that fluctuations of the transepithelial potential and spike responses to temperature stimulation reflect changes in the potential difference on the basal membrane of the receptor cells, which is described by a relationship of the Nernst's or Goldman's equation type.I. P. Pavlov Institute of Physiology, Academy of Sciences of the USSR, Leningrad. I. M. Sechenov, Institute of Evolutionary Physiology and Biochemistry, Academy of Sciences of the USSR, Leningrad. Pacific Institute of Oceanology, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Neirofiziologiya, Vol. 12, No. 1, pp. 67–74, January–February, 1980.     

Principles of organization and evolution of systems of regulation of functions

Evolution of living organisms is closely connected with evolution of structure of the system of regulations and its mechanisms. The functional ground of regulations is chemical signalization. As early as in unicellular organisms there is a set of signal mechanisms providing their life activity and orientation in space and time. Subsequent evolution of ways of chemical signalization followed the way of development of delivery pathways of chemical signal and development of mechanisms of its regulation. The mechanism of chemical regulation of the signal interaction is discussed by the example of the specialized system of transduction of signal from neuron to neuron, of effect of hormone on the epithelial cell and modulation of this effect. These mechanisms are considered as the most important ways of the fine and precise adaptation of chemical signalization underlying functioning of physiological systems and organs of the living organism