Phytohemagglutinins from Phaseolus vulgaris L. and Pisum sativum Seeds

The isolation and purification of phytohemagglutinins fromPhaseolus vulgarisandPisum sativum seeds are reported     

Further resolution of alpha-fetoprotein glycoforms by two-dimensional isoelectric focusing and lectin affinity electrophoresis

Human alpha-fetoprotein (AFP) from serum of patients with cirrhosis and hepatocellular carcinoma (HCC) was separated into several bands by IEF and by erythroagglutinating phytohemagglutinin (E-PHA) affinity electrophoresis. These AFP bands were directly compared in 2-D IEF and E-PHA affinity electrophoresis. IEF of serum AFP was run in 1% agarose IEF gel with 3% Pharmalyte 4.5-5.4. After IEF, a part of the gel was stained for AFP and another part of the gel corresponding to the area of separated AFP bands was cut in 1 mm x 39 mm along the focused direction and transferred to a trough in 1% agarose gel with 0.3 mg/mL E(4)-PHA for second-dimensional affinity electrophoresis. Separated 2-D AFP spots were visualized by antibody-affinity blotting and identified by combining the systems of Johnson et al.. (Johnson, P. J., Ho, S., Cheng, P., Chan, A. et al.., Cancer 1995, 75, 1663-1668) for AFP-I-+IV and of Taketa et al.. (Taketa, K., Ichikawa, E., Taga, H., Hirai, H., Electrophoresis 1985, 6, 492-497) for AFP-P1-5. AFP-P2, the major AFP glycoform, was composed of AFP-I, AFP+I, and AFP+II; AFP-P3, a nonspecific monosialo-AFP, was composed of AFP+II; AFP-P4, HCC-specific monosialo-AFP, was composed of AFP+II, AFP+III, and AFP+IV; and malignancy-related AFP-P5 was composed of AFP+I and AFP+II. Monosialo-AFP (AFP+II) was recovered in all the glycoforms of AFP-P2, -P3, -P4, and -P5; thus, AFP-P4 is more specific to HCC than monosialylated AFP+II.     

基于等温滴定量热法表征的红细胞凝集反应热动力学特性研究

采用等温滴定量热法研究植物凝集素(PHA)作用于20%家兔血红细胞(RBC)的凝集反应过程, 以生物热动力学参数表达凝集反应动力学特征. 结果表明, PHA与家兔血红细胞凝集反应的平衡常数K为3.24×10⁵ L•mol^－1, 反应焓变( )为－238.548 kJ•mol^－1, 反应自由能( )为－32.722 kJ•mol^－1, 反应熵变( )为－0.664 kJ•mol^－1•K^－1. 反应为放热反应(Q＞0), 可自发进行(ΔG＜0), 反应为焓驱动、熵减过程(ΔH＜0, ΔS＜0, |ΔH|＞|TΔS|), 由化学键合作用、氢键和范德华力推动, 反应体系最终处于稳定有序状态. 所建立的微量量热法可以客观表征凝集反应的热动力学过程, 也为其他抗原抗体类型反应的过程评价方法提供新的技术参考.     

植物血凝素与金色葡萄球菌肠毒素刺激人外周血单个核细胞的比较研究

比较了植物血凝素(PHA)与金色葡萄球菌肠毒素(SEA)对外周血单个核细胞(PBMCs)的刺激效果。取健康人外周静脉血,分离得到PBMCs,分别加入PHA及SEA进行刺激并孵育12 h,利用原子力显微镜和倒置荧光显微镜观察细胞形态变化,利用量子点联合共聚焦显微镜观察活化后细胞膜表面CD3、CD69的分布情况,利用流式细胞术检测淋巴细胞活化早期细胞分化抗原CD69分子表达的变化情况。结果显示,丝裂原PHA刺激的淋巴细胞大多成群聚集,而超抗原SEA刺激的淋巴细胞大多呈分散状,且二者形态有明显差异;两组活化后淋巴细胞的体积均大于静息组,且活化过程中发生极化作用,迁移淋巴细胞,形成膜突起;丝裂原和超抗原刺激淋巴细胞12 h后,使淋巴细胞表达CD69抗原分子,但在量表达上存在差异性(PHA:39.5%±8.7%;SEA:8.3%±1.8%),抗原分子CD3和CD69在膜表面呈不均匀分布,且SEA活化后的T淋巴细胞表面受体CD3和CD69分子在空间上形成了微结构域;外周单个核细胞中其它非T细胞在丝裂原或者超抗原的刺激下也能表达活化抗原分子CD69。