鸡和猪分泌型免疫球蛋白A结构蛋白的比较

通过SephadexG 2 0 0凝胶过滤和DEAE纤维素柱 ,分别从胆汁和初乳中提纯鸡和猪的分泌型免疫球蛋白A (SIgA)。SDS PAGE结果显示 ,鸡SIgA的轻链分子量约为 2 6 0 0 0～ 2 80 0 0 ,与鸡IgG的轻链分子量相似 ,而重链分子量约为 670 0 0～ 70 0 0 0 ,比鸡IgG的分子量要大。猪的SIgA与猪IgG的轻链和重链的分子量均相同。轻链的分子量约为 2 6 0 0 0～ 2 80 0 0 ;重链的分子量约为 53 0 0 0～ 570 0 0。猪SIgA中J链的分子量为 1 6 0 0 0～ 1 70 0 0。本实验证明鸡SIgA轻链的分子量与猪的SIgA的轻链相似 ,而鸡SIgA重链的分子量则高于猪的SIgA的重链

The comparison of secretary immunoglobulin A in swine and chicken

The secretary immunoglobulin A (SIgA) was purified from chicken bile and swine colostrum milk with Sephadex G 200 gel filtration and DEAE cellulose chromatography respectively. The purified SIgA was electrophoresed on the SDS PAGE gel. The results showed that the IgA of chicken is composed of heavy and light chains. The molecular weight of heavy chain is about 67 000～70 000, the light chain is about 26 000～28 000. The IgG of chicken has the same molecular weight of light chain as SIgA. But the heavy chain of chicken SIgA has a higher molecular weight than that of IgG. The IgA of swine is composed of heavy and light chains. Unlike chicken, the heavy and light chains (respectively 53 000～57 000 and 26 000～28 000) of swine IgA has the same molecular weight as IgG. Moreover, J chain appeared in SDS PAGE gel with a molecular weight of 16 000～17 000. The results showed that the light chains of chicken SIgA had the same molecular weight as the light chains of swine SIgA, but the heavy chains of chicken SIgA had a higher molecular weight than the heavy chains of swine SIgA.