Houdebine L M
Unité de Différenciation Cellulaire, Institut National de la Recherche Agronomique, Jouy-en-Josas.
Rev Fr Transfus Hemobiol. 1993 Jan;36(1):49-72. doi: 10.1016/s1140-4639(05)80168-6.
The bulky production of recombinant proteins can be achieved by procaryotes or eucaryotes cells. Cells from higher eucaryotes may be required when proteins have to be modified post-transcriptionally (glycosylation phosphorylation, cleavage, folding...). Cells from higher vertebrates in culture are used to prepare proteins like human factor VIII and erythropoietin. The use of transgenic organism has been suggested to reach the same goal. Indeed a whole living organism allows a very potent amplification, the number of cells involved in the biosynthesis of the recombinant proteins being very numerous and in the best metabolic conditions. Biological fluids (blood, milk, insect hemolymph, egg white...) and possibly organs from transgenic animals are a priori the best sources of recombinant proteins. Blood is abundant and it is a by-product of slaughter house. Its composition is relatively complex and the circulating recombinant proteins may heavily alter health of animals. Milk is very abundant, its composition is relatively simple, it is poor in proteolytic enzymes and it can be collected easily. Hemolymph from insects is relatively scarce. Egg white will be a possible source of recombinant proteins, when transgenesis has become more accessible in birds. Organs from transgenic animals should be solicited only when a particular cell type is required for the biosynthesis of the recombinant proteins. Milk appears therefore, presently, as the best source of recombinant proteins from transgenic animals. About 15 public and private laboratories try to use these techniques. They consist in preparing vectors containing regulatory regions of one of the milk proteins genes and the coding part (cDNA or gene) of the corresponding proteins to be produced. The transfer of these gene constructs to mouse, rabbit, sheep, goat, pig, shows that these techniques are indeed very promising. A single protein, human alpha 1-antitrypsin produced in milk of transgenic sheep, has presently reached the preparation at an industrial scale. This method has two theoretical limitations: 1) some of the proteins secreted in milk may be not matured as their native counterparts. Experiments carried out so far (about 20 proteins has been produced at an experimental scale) indicate that the mammary cell is able to achieve glycosylation in a correct way; 2) a significant proportion of the recombinant proteins migrate from the alveolar compartment of the mammary gland to blood circulation and they can alter health of lactating animals.(ABSTRACT TRUNCATED AT 400 WORDS)
重组蛋白的大量生产可通过原核细胞或真核细胞来实现。当蛋白质需要进行转录后修饰（糖基化、磷酸化、切割、折叠等）时，可能需要高等真核生物的细胞。培养的高等脊椎动物细胞可用于制备如人凝血因子VIII和促红细胞生成素等蛋白质。有人建议使用转基因生物来达到同样的目的。实际上，整个活体生物能够实现非常有效的扩增，参与重组蛋白生物合成的细胞数量众多且处于最佳代谢条件。生物体液（血液、乳汁、昆虫血淋巴、蛋清等）以及转基因动物的器官理论上是重组蛋白的最佳来源。血液丰富且是屠宰场的副产品。其成分相对复杂，循环中的重组蛋白可能会严重影响动物健康。乳汁非常丰富，其成分相对简单，蛋白水解酶含量低且易于收集。昆虫的血淋巴相对稀少。当鸟类的转基因技术更加成熟时，蛋清将成为重组蛋白的一个可能来源。只有在重组蛋白生物合成需要特定细胞类型时，才应利用转基因动物的器官。因此，目前乳汁似乎是转基因动物重组蛋白的最佳来源。大约15个公共和私人实验室正在尝试使用这些技术。这些技术包括制备含有一种乳蛋白基因调控区和待生产相应蛋白编码部分（cDNA或基因）的载体。将这些基因构建体转移到小鼠、兔子、绵羊、山羊、猪身上，表明这些技术确实非常有前景。目前，转基因绵羊乳汁中产生的一种单一蛋白质——人α1 -抗胰蛋白酶已达到工业化生产规模。这种方法有两个理论局限性：1）乳汁中分泌的一些蛋白质可能不像其天然对应物那样成熟。目前进行的实验（已在实验规模上生产了约20种蛋白质）表明乳腺细胞能够正确地进行糖基化；2）相当一部分重组蛋白从乳腺的腺泡腔迁移到血液循环中，它们会影响泌乳动物的健康。（摘要截断于400字）
