Human Recombinant Insulin Replaces Animal Insulin and Semisynthetic Insulin Obtained By Modification of Animal Insulin

 

Human Recombinant Insulin, first made with genetic engineering in 1982, has been the first synthetic enzyme ever made using genetic engineering. Before that, genetically engineered animals, such as cattle and pigs, were the sole source of animal insulin. Recombinant human insulin is the result of a successful breeding campaign between different strains of the HIV virus, which destroys the glycogen-producing pancreatic islet cells in animals. These cells are then replaced by copies of the human insulin gene, making humans the true insulin makers.

The first animal insulin was made in pigs with the HIV-1 gene, but this did not produce any healthy mice. In order to make an uninfected animal better, researchers introduced the bill insulin gene into a group of hamsters without infecting them, and these animals lived for more than two months without needing any insulin treatment at all. The pili gene was inserted into the hamsters' genes instead of the glycogen-producing islets, thus replacing the inefficient, dying cells with new ones. Since the experiment was done with hamsters, no human insulin treatment had to be made, and the medical company that conducted the study was later sued by several patients, who claimed that the medical research was meant to profit from their suffering by making as many people as possible ill.

As a result of the lawsuit, the company released the pili-Glin gene, which is still the most extensively used insulin for diabetes therapy. Another company, NovoLogic, has released an unapproved, 3rd generation form of the glucose-reducing hormone called NPH Premixed Insulins, or NPJ. The U.S. FDA has not approved either form of the medication, and both have shown very low success rates in treating diabetes. The main reason for this may be that the transgenic mice introduced into the diabetes therapy studies did not contain the pili gene. This may explain why so few trials have succeeded with NPH Premixed Insulins, and why no one is really sure whether it works at all.

No clinical study report has yet been released linking NPH insulin to any health benefit. One reason for this may be that the transgenic mice used in those studies failed to develop the NPH protein within their tissues. Another reason that the effectiveness of NPH is in doubt is that no one yet knows how to produce copies of the wild gene in the laboratory. This could be accomplished using the genetic engineering methods currently being used to produce different viruses. If researchers can successfully insert the wild gene into cells of living organisms, then they have a way of producing human insulin that is highly effective.

At the same time, though, no clinical studies have yet established whether these engineered transgenic insulin proteins will have human consequences. For now, the benefits of Insulin/R-Abs seem to outweigh any risks. Human Recombinant Insulin is now available from several pharmaceutical companies and is expected to become an important part of the diabetes treatment regimen in a few years. It will replace most of the complex forms of insulin currently on the market, and there are currently no plans to make nph insulin from any other source. There is a possibility that further studies of novel therapeutic proteins will lead to new types of human insulin formulations, but at this time there is no such prospect.