小鼠Foxp3抗血清的制备及应用

目的:制备高效价的特异性小鼠Foxp3抗血清,并初步应用于正常小鼠组织的Foxp3表达的鉴定.方法:构建重组质粒pGEX-6p-2/Foxp3,并转化至E.coli BL21(DE3)中进行大量诱导表达,用纯化的重组融合蛋白免疫新西兰兔,制备抗血清.以制备的抗血清为一抗,Western blot检测小鼠组织的Foxp3蛋白的表达.结果:SDS-PAGE及Western blot鉴定,诱导表达及纯化的重组融合蛋白能被抗GST单克隆抗体(mAb)识别,在Mr 45 000附近有特异条带,与预期融合蛋白大小一致,获得的抗血清效价在1:12 800以上,该抗血清能特异性识别NIH3T3细胞中表达的Foxp3蛋白.Western blot鉴定结果显示在脾脏、胸腺、淋巴结中Foxp3蛋白有较高表达,胃也有少量的表达,而骨骼肌、脂肪组织未见表达.结论:制备了高效价的特异性小鼠Foxp3抗血清,并可用于正常小鼠组织的Foxp3蛋白的表达鉴定,为进一步研究Foxp3奠定了实验基础.

Preparation and application of anti-serum against mouse Foxp3

AIM:To prepare the high titer and specific anti-serum against mouse Foxp3 and then use them to identify Foxp3 expression in normal mouse tissues. METHODS: The Foxp3 fragment was amplified by polymerase chain reactions(PCR) and cloned into the prokaryotic expression vector pGEX-6p-2. The recombinant plasmid pGEX-6p-2/Foxp3 was transformed into E.coli BL21(DE3) to be expressed. The expressed fusion protein GST-Foxp3 was analyzed by SDS-PAGE and Western blot. The polyclonal clanti-serum was obtained by immunizing New Zealand rabbits with the purified fusion protein as antigen. The Foxp3 expression in normal mouse tissues was detected by Western blot with the anti-serum. RESULTS: The expressed products were analyzed by SDS-PAGE and Western blot. The results showed that the molecular weight of the expressed protein was about 45 000. The titer of the anti-serum was above 1:12 800. We observed that the anti-serum could recognize Foxp3 protein expressed in NIH3T3 cells by immunoblotting. Western blot results showed that the Foxp3 protein was expressed highly in spleen, thymus and lymph nodes, less expressed in stomach, but not expressed in skeletal muscle and adipose tissue. CONCLUSION: High titer antiserum against mouse Foxp3 is produced and can be used to identify the Foxp3 expression in normal mouse tissues.