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Human immunodeficiency virus (HIV) treatment

January 30, 2004

Russian researchers have developed a medication capable of protecting against various human immunodeficiency virus (HIV) strains. Their effort has been supported by the International Scientific Technical Center.

Intense search for efficacious human immunodeficiency virus treatment carried out by scientific laboratories worldwide has not yet brought noticeable results. Nevertheless, researchers are making progress. In particular, they have determined the way the HIV penetrates a cell. To this end, virus protein gp120 should necessarily enter the interaction with special proteins located on the surface of the cellular membrane. If all such sites are occupied on gp120, then the virus will not be able to interact with cellular receptors and would not penetrate the cell. This principle makes the basis for the action of medication developed by researchers of the VEKTOR State Research Centre for Virology and Biotechnology and Publishing Centre for Biomodulators and Drug Compounds, Zdorovie (Health) Scientific Research Company (Moscow).

Having analysed published data and the structure of respective cellular membrane proteins, the researchers selected and synthesised 5 peptides (short proteins). These peptides represent synthetic analogues to fragments of cellular membrane proteins CCR5 and CxCR4, the HIV interacts with, when penetrating the cell. Experiments carried out with peptides, various virus strains and cell cultures have proved that peptides by themselves do not protect cells from the virus. However, if these peptides are placed on the polymeric polyanionic matrix, i.e. polymer, the chain links of which are positively charged, then the medication would acquire anti-HIV activity. The peptides must necessarily be combined with the matrix by chemical bond, a simple mechanical mixture of components, as well as pure matrix, possesses no protective function.

The researchers judged about the extent of antiviral activity by the viability of human cell culture after 4 days of incubation with the virus, and also by the amount of virus protein ?24 contained in the nutrient medium. Some combinations of peptides and the matrix even at a very low concentration (several ten-thousandth gram per millilitre) inhibit virus reproduction and virus protein synthesis by 90% as compared to the reference level. The researchers tested toxicity of the medication and its components on the culture of human lymphoid cells. All the five peptides, matrix and their complex are innocuous for the cells even at the concentration of 1 milligram per millilitre, which exceeds the efficacious drug dose by several hundreds of times.
The researchers tested the medication antiviral effectiveness on virus strains, which interact with various types of cells and correspondingly receptors.

The provisional data has proved that the medication is efficacious for any viral strain regardless of its specificity. The researchers are not going to stop at the achieved results. They have already outlined possible ways to improve the medication. According to their idea, the complex medication for AIDS therapy should prevent the initial contact between the virus and the cell. These medications occupy the sites of virus interaction with cellular receptors, compete with them and thus keep the virus in dormat state, preventing the virus from penetrating the cell, outside which the HIV cannot survive. In the scientists' opinion, results of their research testify to the fact that design of such medications is promising.

Informnauka (Informscience) Agency