Molecular cloning of a pig homologue of membrane cofactor protein (CD46).
Molecular cloning of a pig homologue of membrane cofactor protein (CD46).
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膜辅因子蛋白 (CD46) 的猪同源物的分子克隆。
DOI：
10.1093/intimm/9.6.869
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发表时间：
1997
影响因子：
4.4
通讯作者：
T. Kinoshita
中科院分区：
文献类型：
--
作者：
K. Toyomura;T. Fujimura;H. Murakami;T. Natsume;T. Shigehisa;N. Inoue;J. Takeda;T. Kinoshita
表达人类补体调节蛋白的转基因猪的器官正在评估是否可以作为移植的替代方案。猪器官移植的一个主要障碍是预先存在的抗体和补体引起的超急性排斥反应。猪细胞对人类补体非常敏感，可能是因为猪细胞表面补体调节蛋白对人类补体无效。通过转基因表达人补体调节蛋白，如衰变加速因子和膜辅助因子蛋白(MCP或CD46)，可使猪细胞对人补体产生抵抗力，从而防止超急性排斥反应。为了在适当的位点表达足够水平的人补体调节蛋白，猪膜结合补体调节蛋白基因的调控元件将是有用的。为了获得它们的cDNA，我们用猪的cDNA文库转染人的细胞，通过与猪补体孵育的方法筛选细胞，并回收了质粒。我们克隆了猪MCP的同源基因pMCP。该基因编码363个氨基酸，与人MCP的氨基酸同源性为42%。PMCP由4个短的共识重复序列组成，包括一个Ser/Thr/Pro富含结构域，以及跨膜和细胞质结构域。缺乏跨膜区和胞浆区的重组可溶性pMCP在C3b裂解中具有因子I辅因子活性，表明它在功能上和结构上与MCP同源。用抗pMCP单抗进行流式细胞仪分析表明，pMCP在所有的血白细胞、红细胞以及内皮细胞和上皮细胞上均有表达。
Organs of transgenic pigs that express human complement regulatory proteins are under assessment as an alternative to transplantation. A major barrier to the transplantation of pig organs is the hyperacute rejection caused by pre-existing antibodies and complement. Pig cells are very susceptible to human complement, presumably because pig cell-surface complement regulatory proteins are inefficient against it. Expression of human complement regulatory proteins, such as decay-accelerating factor and membrane cofactor proteins (MCP or CD46), by means of transgenes would confer resistance to human complement upon pig cells, thereby preventing hyperacute rejection. To express sufficient levels of human complement regulatory proteins at appropriate sites, regulatory elements of genes of pig membrane-bound complement regulatory proteins would be useful. To obtain their cDNAs, we transfected human cells with a pig cDNA library, selected cells by incubation with pig complement and rescued the plasmids. We cloned a cDNA for the pig homologue of MCP, pMCP. The cDNA encoded a predicted protein of 363 amino acids with 42% amino acid identity with human MCP. The pMCP consisted of four short consensus repeats, a Ser/Thr/Pro-rich domain, and transmembrane and cytoplasmic domains. Recombinant soluble pMCP that lacked transmembrane and cytoplasmic domains had factor I cofactor activity in C3b cleavage, indicating that it is functionally, as well as structurally homologous to MCP. FACS analysis with anti-pMCP mAb demonstrated that pMCP is expressed on all blood leukocytes, erythrocytes, and on endothelial and epithelial cell lines.
影响因子：
4.4
作者：
Bin Li;C. Sallee;M. Dehoff;S. Foley;Hector Molina;V. Holers
通讯作者：
Bin Li;C. Sallee;M. Dehoff;S. Foley;Hector Molina;V. Holers
影响因子：
56.9
作者：
KOOYMAN, DL;BYRNE, GW;LOGAN, JS
通讯作者：
LOGAN, JS