重组猪IFN-α原核表达及其活性分析

为了表达猪重组α干扰素(rIFN-α)并对它的生物学特性进行研究,本研究采用RT-PCR从猪脾淋巴细胞中扩增出猪IFN-α基因,以pPROExHTa为载体构建了表达重组质粒polFN-α,转化宿主菌BL21,经IPTG诱导猪rIFN-α获得了表达,其分子量约22 ku.该重组蛋白以包涵体形式存在,其表达量占总菌体蛋白7%.粟用Ni-Ni金属螯合亲和层析方法纯化,其纯度达到80%以上,包涵体经复性后,在WISH/VSV系统上,采用细胞病变抑制法测定表明,其稀释度在小于1:103时才有抗病毒活性.本实验表达的猪rIFN-α具有一定的抗病毒活性,为研究具有广谱抗病毒效应的猪干扰素具有重要意义.     

猪IFN-α在巴斯德毕赤酵母中的分泌表达

为了获得高效抗病毒活性的猪α-干扰素蛋白,采用PCR法扩增获得猪α-干扰素基因完整的开放阅读框(ORF),构建重组表达质粒pPICZαC-IFN,电击转化毕赤酵母感受态细胞X33.挑阳性菌落诱导表达,离心取上清,SDS-PAGE和Western-blotting分析,可见1条相对分子质量约19 400的清晰蛋白条带,与理论值相符,表明表达产物为猪α-干扰素.在Vero细胞上检测该干扰素抗VSV的活性为4.04×106IU/L.     

Lymphoma with cutaneous involvement in three domestic rabbits (Oryctolagus cuniculus)

Three domestic rabbits ( Oryctolagus cuniculus ) with cutaneous lymphoma are described. Two rabbits were young (7 weeks and 1 years) and were euthanized within 1 week of showing clinical signs. Lymphoma was found in the skin and internal organs. The third rabbit was 9.5 years of age, and lived for more than 1 year after diagnosis. No response was seen to either 2 months of alpha-interferon administration or a 2.5-week course of isotretinoin treatment. After 1 year the rabbit died suddenly; the owner refused necropsy. Immunologic stains of the tumour in all three rabbits showed T cells to be the lymphoma cell type.