恒定链CLIP的2个片段在增强体液免疫效果的比较

Effect difference between two segments in invariant chain CLIP on humoral immune

摘要:

摘要:【目的】比较恒定链(invariant chain，Ii) CLIP 的2个片段(PBS、GBS)影响免疫载体增强体液免疫的效果。【方法】首先，构建了基于小鼠Ii功能片段与新城疫病毒抗原肽F2的6个嵌合体(Cyt/TM/F2、Cyt/TM/F2/GBS、Cyt/TM/PBS/F2、Cyt/TM/F2/TRIM、Cyt/TM/F2/GBS/TRIM、Cyt/TM/PBS/F2/TRIM);其次，定向克隆至原核表达载体pET-32a中，并转化大肠杆菌Rosetta(DE3)诱导表达和纯化目的蛋白;最后，免疫小鼠，经间接ELISA法测定血清抗体效价，以及比较分析不同嵌合体免疫组免疫效果。【结果】一是所构建的含不同Ii功能片段/F2嵌合体的6个免疫组，均比单独F2的免疫组提高抗体水平1.5－4.9倍;二是在上述6个免疫组中，含CLIP的PBS或GBS的免疫组比不含CLIP 的免疫组增强1.6－2.4倍;三是含PBS比含GBS的免疫组增强1.5倍。【结论】Ii胞浆区、跨膜区具有增强免疫效果的作用，而CLIP的PBS在Ii免疫载体中的作用优于GBS。

Abstract:

Abstract:［Objective］To compare the effect between two segments (PBS and GBS) of ClassⅡ-associated invariant chain peptide (CLIP) of invariant chain (Ii) on humoral immune by immune carrier．［Methods］First six hybrids containing Newcastle disease virus (NDV) epitope F2 and Ii segments (Cyt/TM/F2，Cyt/TM/F2/GBS，Cyt/TM/PBS/F2，Cyt/TM/F2/TRIM，Cyt/TM/F2/GBS/TRIM，Cyt/TM/PBS/F2/TRIM ) were reconstructed respectively．Then they were inserted into the prokaryotic expression vector pET-32a and transformed into E.coli Rosetta (DE3) to induce the expression of the recombinant proteins．Finally mice were immunized with these purified fusion proteins，the specific antibody titers were detected with ELISA，to compare and analyze the effect among different groups on the immune response．［Results］All the six groups immunized with these hybrids increased antibody titers (from 1.5-fold to 4.9-fold，respectively) compared with the group immunized with F2 alone．Within the above six groups，the hybrids containing either PBS or GBS had higher antibody titers from 1. 6-fold to 2.4-fold than the hybrids without the both segments．However，the group of the hybrid containing PBS had a 1.5-fold antibody titer higher than the group of GBS hybrid． ［Conclusion］ Ii cytosolic and transmembrane domains could increase the immune response，while the segment PBS behaved better than GBS in an immune vector based on Ii．