Recombinant insulin

Oral Inhalation Insulin Recombinant human Exubera Pfizer 1 mg = 10-20 0.5-1.5 6 1 mg, 3 mg blister packs... 

Apidra (Insulin Recombinant rapid- Engineered B3 asparagine Aventis 2004... 

Lantus (Insulin Recombinant long-acting Engineered A 21 asparagine Aventis 2000 (USA... 

Human Insulin (Recombinant) Humulin, Novolin, Velosulin BR 215... 

Human insulin was the first commercial health care product produced by recombinant DNA technology ZjEliJLilly,.the producer of this synthetic insulin, often relied on HPLC to confirm the structure and to determine the potency of synthetic human insulin. The story behind Lilly s recombinant DNA-produced insulin is described in an article in Science (1) High performance liquid chromatography (HPLC) techniques developed at Lilly can detect proteins that differ by a single amino acid, and HPLC tests show human insulin (recombinant DNA) is identical to pancreatic human insu-... 

Johnson, I.S. (1982). Authenticity and purity of human insulin (recombinant DNA). Diabetes Care 5 (Suppl. 2), 4 12. 

Human Insulin, Recombinant " " Human insulin was the first pharmacologically active biological macromol-eculc lo be produced through genetic engineering. The FDA approved the drug in 1982 for the treatment of type I (insulin-dependent) diabetes (.see Chapter 2S). The insulin protein is a two-chain polypeptide containing SI amino acid residues. Chain A is composed of 21 amino acid.s. and chain B con-... 

Recombinant DNA techniques are used to produce proteins that have therapeutic properties. One of the first such proteins to be produced was human insulin. Recombinant DNA corresponding to the A chain of human insulin was prepared and inserted into plasmids that were used to transform E. coli cells. The bacteria then synthesized the insulin chain, which was purified. A similar process was used to obtain B chains. The A and B chains were then mixed and allowed to fold and form disulfide bonds, producing active insulin molecules (Fig. 17.11). Insulin is not glycosylated, so there was no problem with differences in glycosyltransferase activity between E. coli and human cell types. 

Recovery nd Purifica.tion. The production of EH Lilly s human insulin requires 31 principal processing steps of which 27 are associated with product recovery and purification (13). The production process for human insulin, based on a fermentation which yields proinsulin, provides an instmctive case study on the range of unit operations which must be considered in the recovery and purification of a recombinant product from a bacterial fermentation. Whereas the exact sequence has not been pubUshed, the principle steps in the purification scheme are outlined in Figure la. 

This reversed-phase chromatography method was successfully used in a production-scale system to purify recombinant insulin. The insulin purified by reversed-phase chromatography has a biological potency equal to that obtained from a conventional system employing ion-exchange and size-exclusion chromatographies (14). The reversed-phase separation was, however, followed by a size-exclusion step to remove the acetonitrile eluent from the final product (12,14). 

Therapeutics. Therapeutic materials represent a class of polypeptides that are a low volume, high value product. The production system need not be very efficient but the quaHty of the recombinant protein has to be extremely pure (33,34). Thus high cost mammalian production systems can be tolerated. However, some of the therapeutic proteins such as insulin, human growth hormone, interleukins, interferon, and streptokinase are produced microbially. 

NPH Isophane Human Insulin Suspension. NPH isophane insulin, also called Humulin N, Insulatard NPH Human, or Novolin N is an intermediate-acting form of human insulin produced by recombinant DNA techniques. Mixtures Humulin 70/30 and Novolin 70/30 contain 70% NPH isophane and 30% regular, whereas Humulin 50/50 contains 50% NPH isophane and 50% regular. It is adrninistered subcutaneously and should not be given intravenously. Absorption is delayed because the insulin is conjugated with protamine in a complex of reduced isoelectric solubiUty. Therapeutically, this preparation is probably comparable to purified porcine NPH insulin. However, human NPH insulin may have a slightly shorter duration of action than comparable purified porcine products. 

It is often important to control the CSD of pharmaceutical compounds, eg, in the synthesis of human insulin, which is made by recombinant DNA techniques (1). The most favored size distribution is one that is monodisperse, ie, all crystals are of the same size, so that the rate at which the crystals dissolve and are taken up by the body is known and reproducible. Such uniformity can be achieved by screening or otherwise separating the desired size from a broader distribution or by devising a crystallization process that will produce insulin in the desired form. The latter of these options is preferable, and considerable effort has been expended in that regard. 

Recombinant DNA technology now verges on the ability to engineer at will the genetic constitution of organisms for desired ends. The commercial production of therapeutic biomolecules in microbial cultures is already established (for example, the production of human insulin in quantity in E. coli cells). Agricultural crops with desired attributes, such as enhanced resistance to her-... 

Insulin, interferon Recombinant E. coli Baker s yeast Human therapy... 

Human insulin is derived from a biosynthetic process using strains of Escherichia coli (recombinant DNA, rDNA). Human insulin appears to cause fewer allergic reactions than does insulin obtained from animal sources. Insulin analogy, insulin lispro, and insulin aspart are newer forms of human insulin made by using recombinant DNA technology and are structurally similar to human insulin. 

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