镉对体外培养鸡脾淋巴细胞膜物理特性的影响

为了探讨镉对鸡脾淋巴细胞膜物理特性的影响,以终浓度为10 μmol/L CdCl2对体外培养淋巴细胞进行染毒,培养12、24、36、48、72 h后,收集细胞上清液,提取细胞膜,分别检测乳酸脱氢酶(LDH)的活性、淋巴细胞膜偏振度与微黏度和唾液酸(SA)含量.结果显示,淋巴细胞内的LDH漏出率增加(P＜0.01),淋巴细胞膜荧光偏振度和微黏度增加(P＜0.01或P＜0.05),SA含量降低(P＜0.01).研究结果表明,镉能改变淋巴细胞膜通透性,降低淋巴细胞膜的流动性.     

4种中药多糖对小鼠脾淋巴细胞增殖的影响

本试验旨在研究黄芪多糖(APS)、芦荟多糖(AP)、银耳多糖(TFPS)、黑木耳多糖(AAP)4种中药多糖对小鼠脾淋巴细胞增殖的影响.将4种多糖体外作用于小鼠脾淋巴细胞;采用MTT法测细胞增殖活性.结果显示,与对照组相比较,4种多糖在浓度为400 μg/mL时均能促进静止态淋巴细胞增殖;多糖协同ConA或LPS作用于淋巴细胞,4种多糖表现不同程度的增殖促进作用.在静止态淋巴细胞增殖以及协同丝裂原作用于淋巴细胞的增殖试验中,芦荟多糖所表现的促进增殖作用较强于其他3种多糖.     

双翅目昆虫对荷斯坦奶牛护身行为及外周血液中淋巴细胞亚群的影响

为了研究荷斯坦奶牛受到双翅目昆虫侵袭时奶牛个体所表现的护身行为、外周血液中淋巴细胞亚群的变化规律,试验期间每日跟踪观察奶牛护身行为1 h,记录每5 min内侵袭奶牛的双翅目昆虫数目和奶牛的护身行为出现次数,定时采血用流式细胞仪检测外周血液中CD3+、CD4+、CD8+ T淋巴细胞和CD21+B淋巴细胞等的变化规律.结果表明:奶牛护身行为随飞来昆虫的数量而变化;外周血液中的CD3+、CD4+、CD21+水平随双翅目昆虫数量的增多而降低;CD8+水平随双翅目昆虫数量的增多而升高.     

流式细胞术在活化T淋巴细胞检测中的应用

免疫细胞的活化和增殖是免疫应答产生的一种标志.静止T淋巴细胞经过抗原刺激活化后,表现出一系列的特征,如细胞膜表面活化分子的表达、细胞分裂和产生细胞因子等.近年来,已有利用流式细胞术(FCM)通过检测免疫细胞活化后的特性,来分析抗原特异性免疫应答及其应答规律的报道.论文分别从几个不同的角度综述了FCM在活化T淋巴细胞检测中的应用.     

Transfection efficiency and cytotoxicity in human T lymphocytes infected with Ad5 adenoviral vector

AIM:To determine the transfection efficiencies and to evaluate the cytotoxicity of infection with Ad5 adenoviral vector in human T lymphocytes. METHODS:The T-lymphoma Jurkat cell line, normal CD3+ T cells and pre-stimulated CD3+ T cells were transfected with Ad5 adenovirus at multiplicities of infection (MOI) ranging from 20 to 400. GFP expression was analyzed by flow cytometry 48 h after transfection. The cells were harvested 24 h, 48 h and 72 h after transfection. The cell cycle was analyzed using propidium iodide staining and the apoptosis of T lymphocytes was detected by annexin V/7-AAD staining. Trypan blue exclusion assay was used to determine the survival cell numbers after 48 h or 72 h of transfection. RESULTS:The transfection of primary human T cells by the Ad5 virus was less efficient than that of a T-lymphoma cell line. Similar transfection efficiency was observed in both CD4+ T lymphocytes and CD8+ T lymphocytes. The activation of T lymphocytes resulted in a decrease in Ad5 transfection efficiency in CD8+ T cells. Following transfection (24 h, 48 h and 72 h), the percentages of G 0/G 1-phase cells, S-phase cells, G 2/M-phase cells and apoptotic cells at all MOI did not change significantly. Therefore, transfection by the Ad5 adenoviral vector did not influence the cell cycle and survival cell numbers. CONCLUSION:The Ad5 adenoviral vector, which shows little cytotoxicity to T lymphocytes, may be a valuable tool for T cell receptor gene therapy.     

Isolation and characterization of cytotoxic small peptides, α-casecidins, from bovine αs1-casein digested with bovine trypsin

Cytotoxic peptides were isolated from a trypsin digest of bovine αs1‐casein by a combination of ion‐exchange column chromatography and reversed‐phase high‐performance liquid chromatography as an indicator of cytotoxicity toward mouse spleen cells. Amino acids of the isolated peptides were sequenced as arginyl‐proly‐lysine, leucyl‐lysyl‐lysine and tyrosyl‐lysine, being compatible with sequences 1–3, 101–103 and 104–105 of bovine αs1‐casein, respectively. The isolated peptides displayed cytotoxicity toward healthy mouse T and B cells and human leukemic T and B cell lines in a commercially available serum‐free medium for lymphocytes, Celgrosser‐P, and were named α‐casecidins. Similar cytotoxicity was confirmed in chemically synthesized peptides corresponding to sequences 1–3, 101–103 and 100–105 of bovine αs1‐casein. The cytotoxicity induced by α‐casecidins was concluded to be because of necrosis, and was diminished in the presence of bovine serum albumin.     

Application of a radioimmunoassay for detection of the major internal antigen (p24) of bovine leukemia virus from cultured lymphocytes of cattle

A sensitive and specific radioimmunoassay for the major internal antigen of bovine leukemia virus has been applied to detecting this protein in cultured lymphocytes of infected cattle. The specificity inherent in this assay offers obvious advantages over a previously described syncytium induction assay for infectious bovine leukemia virus, because false positive reactions due to other viruses such as bovine syncytial virus are avoided. Investigations of various culture conditions indicated that maximal amounts of antigen had been produced after incubation for 72 hr at 37°C. Lymphocyte concentrations of 10⁶?5×10⁷ cells/ml gave satisfactory results. Tests of cultured lymphocytes from bovine leukemia virus infected or bovine leukemia virus-free cattle indicated a comparable sensitivity between the radioimmunoassay and syncytium induction assay in the detection of bovine leukemia virus infections.     

重组牛白细胞介素－2对不同种属动物淋巴细胞的作用

以重组牛白细胞介素－２作用于ＣｏｎＡ活化的不同种属动物的淋巴细胞，结果发现重组牛白细胞介素－２对人、犬、猪、绵羊以及鸡淋巴细胞没有作用；对山羊、豚鼠及小鼠淋巴细胞具有显著作用；对牛、驴和兔淋巴细胞具有极显著的作用。     

不同月龄山羊小肠黏膜免疫相关细胞的数量变化

为揭示不同发育阶段山羊小肠黏膜免疫特点的内在规律，本试验采用组织学和组织化学方法，对0．5、2和12月龄山羊小肠不同肠段的上皮内淋巴细胞、杯状细胞和肥大细胞的分布和数量变化进行了比较研究。结果显示：随着年龄增长，小肠各段上皮内淋巴细胞和肥大细胞的数量逐步增多（P〈0．05），而杯状细胞却逐渐减少（P〈0．05）。上皮内淋巴细胞数从十二指肠至回肠逐渐减少，0．5月龄的回肠上皮内淋巴细胞数仅是十二指肠和空肠的84．45％和98．14％（P〈0．05），肥大细胞的分布规律与上皮内淋巴细胞相似；相反，杯状细胞数从十二指肠至回肠逐渐增多。以上结果提示，在山羊小肠的早期发育中，杯状细胞起着重要的黏膜屏障功能，随着肠道黏膜免疫系统的发育，上皮内淋巴细胞和肥大细胞的黏膜防御作用进一步增强。