Human interferon was discovered back in 1957 by two scientists Isaacs and Lindemann. Thanks to this discovery, a new mechanism of human cellular defense against viral infections was established. Heat-inactivated influenza virus, the authors incubated on the chicken embryo, homogenized chorionalantois and found that the supernatant inhibited the growth of the active virus on chorionalanthosis. The factor that was in the homogenate was called interferon, and its only biological property was considered antiviral protection for many years. It has been established that the producers of interferon are cells of various tissues of humans and animals. Its formation is induced by viruses, somewhat less bacteria, pathogenic fungi, protozoa, the influence of mitogens, synthetic polymers. White blood cells are able to induce the synthesis of interferon already 3-4 hours after the incubation of the virus.
It should be noted that the phenomenon of interference of viruses has long been known. It is based on the possibility of protecting a person against the action of a virulent virus using factors of nonspecific resistance if a less dangerous virus enters the same organism simultaneously or previously. Something similar, that is, the phenomenon of interference is observed among pathogens of bacterial origin in the process of their interaction. It was found that one type of pathogen can inhibit the reproduction of another species and thus change the course of the infection process caused by it. It is proved that when a person or animal is infected with brucellosis, they develop immunity to anthrax bacilli. The interference between brucella and tularemia bacteria is described. There is reason to believe that during bacterial interference an inhibitor is produced that blocks sensitive cells in the macroorganism, which creates unfavorable conditions for the existence of one of the competing pathogens.
According to current data, there are three types of interferon (gamma-immune, fibroblast beta and alpha-leukocyte interferon), which differ in origin, physical and biological characteristics. It should be said that interference between viruses is carried out with the participation of a special inhibitor, which is synthesized by the cells of an infected organism.
It is proved that human interferon is a group of related biologically active peptides that form in cells after stimulation by various inducers. The concentration of interferon, which is able to suppress the biological activity of various viruses in the body, varies quite strongly. The viruses with the outer shell and lipid components (myxoviruses, arboviruses, smallpox viruses) turned out to be the most sensitive to the action of interferon, while picornaviruses and adenoviruses lack the outer shell and are more resistant to this factor. However, there are exceptions when viruses with this shell exhibit increased resistance to the action of interferon (herpes viruses).
Human interferon
The main stimulus for its formation, many consider the penetration of a nucleic acid foreign to the cell, which disrupts the normal genetic balance of cells of various groups. For vertebrate cells, the role of the stimulus is best performed by the nucleic acids of viruses, although other nucleic acids can serve as inducers of interferon. Among the components of microbial cells that are characterized by an interferon effect, endotoxins of gram-negative bacteria, as well as lipopolysaccharides and polysaccharides, in particular pyrogenal, prodigiosan, play an important role. Human interferon is actively produced by exposure to RNA-containing phages and viruses that are well protected from the inhibitory effect of ribonucleases.
As for the properties of interferon, it, in contrast to the known inhibitors acting directly on viruses, affects them through sensitive cells, giving them resistance to viral reproduction. In order for interferon to exhibit an antiviral effect, sensitive cells must have undisturbed synthesis of cellular RNA and cellular proteins.
Recently, as an antiviral agent prescribed "Interferon human recombinant alpha 2". The mechanism of antiviral action is associated with the creation of protective mechanisms in cells not infected with the virus. At the same time, the properties of cell membranes change , which prevents the penetration of the virus into the cell.
The biological properties of interferon include species specificity, which means a selective manifestation of activity in the body of its homologous species. So, for example, interferon produced by chicken embryo cells cannot protect rodents or other mammals, and interferon produced by human leukocytes does not have activity in animals. This property is not absolute and, in some cases, interferon of heterologous origin may be active in the body of another species.