Leong S R, Flaggs G M, Lawman M J, Gray P W
Department of Developmental Biology, South San Francisco, CA 94080.
Vet Immunol Immunopathol. 1989 Jul;21(3-4):261-78. doi: 10.1016/0165-2427(89)90036-6.
A sequence encoding bovine granulocyte-macrophage colony-stimulating factor (GM-CSF) has been identified from a concanavalin A-stimulated bovine lymphocyte cDNA library. This sequence was isolated by hybridization with synthetic oligonucleotide probes based upon the human GM-CSF sequence. This bovine cDNA was engineered for expression and secretion of activity into the periplasmic space of E. coli. Periplasmic extracts contain a 14,500-dalton protein and stimulate colony formation of bovine bone marrow progenitor cells. The predicted protein is 70% homologous with human GM-CSF and 55% homologous with murine GM-CSF. Numerous structural features are conserved among these three proteins, such as location of cysteine residues, glycosylation sites, and overall change. The biological activity of bovine GM-CSF is species specific, since recombinant preparations do not cause proliferation of human or murine bone marrow cells. Similarly, murine GM-CSF does not exhibit activity on cells of bovine or human origin. However, human GM-CSF does stimulate colony formation of bovine bone marrow cells, although the specific activity appears reduced when compared to assays on human cells.
已从伴刀豆球蛋白A刺激的牛淋巴细胞cDNA文库中鉴定出编码牛粒细胞-巨噬细胞集落刺激因子（GM-CSF）的序列。该序列是通过与基于人GM-CSF序列的合成寡核苷酸探针杂交分离得到的。对该牛cDNA进行工程改造，使其在大肠杆菌的周质空间中表达并分泌活性物质。周质提取物含有一种14,500道尔顿的蛋白质，并能刺激牛骨髓祖细胞的集落形成。预测的蛋白质与人类GM-CSF有70%的同源性，与小鼠GM-CSF有55%的同源性。这三种蛋白质之间存在许多保守的结构特征，如半胱氨酸残基的位置、糖基化位点和总体变化。牛GM-CSF的生物活性具有物种特异性，因为重组制剂不会引起人或小鼠骨髓细胞的增殖。同样，小鼠GM-CSF对牛或人源细胞也没有活性。然而，人GM-CSF确实能刺激牛骨髓细胞的集落形成，尽管与对人细胞的测定相比，其比活性似乎有所降低。
