Lectins: obtaining, properties, application in biology and medicine

Abstract

The review material belongs to the scientific and practical issues related to the interdisciplinary direction on the border of nanotechnology, surface chemistry and physics, biology and medicine and is based on the use of natural components in the composition of iron-containing bioactive nanocomposites and magnetic fluids in creating effective vector systems for antitumor therapy with minimized side effects on the human body and improved compatibility with other drugs. Such natural components, which have unique properties, significant and not yet realized potential opportunities for practical use, include, in particular, lectins. The aim of the work is to select and analyze the results of works on the extraction of lectins, the study of their properties and application in biology and medicine. Lectins are a group of substances of protein nature (proteins and glycoproteins) of non-immune origin, which have the ability to reversely and selectively bind carbohydrates and carbohydrate determinants of biopolymers without changes in covalent structure and recognize them with extremely high specificity. Due to this property, they are an ideal tool for reading of code in the structure of specific sugar epitopes on the surface of all cells. Lectins are substances of primary synthesis and are present in all kingdoms, types and classes of living organisms. They mediate cellular communication at the molecular level and are involved in many physiological and pathophysiological processes. Pathogenic bacteria and viruses use lectins to attach to the host tissue, which is one of the prerequisites for the development of infection. Blocking of specific pathogen adhesion with lectin inhibitors is the basis of anti-adhesive therapy, an alternative method of treatment of infections caused by multidrug-resistant bacterial strains. Numerous lectins show antitumor activity and are being studied as potential antitumor drugs. To date, they have found practical application in a number of specialized medical fields, such as histology (detection of carbohydrate structures on the surface of cells and tissues), diagnosis of immunodeficiency and chromosomal abnormalities, transplantology (separation of blood cells and lymphoid cells with different antigenic properties). The prospect of use of lectins in the purification of blood from viruses, pathologically altered glycoproteins, in the targeted delivery of drugs to normal or pathologically altered cells and tissues of the body or to infectious agents is considered very significant. The combination of properties of lectins and magnetically sensitive iron-containing nanocomposites in the composition of magnetic fluids for use in oncology is considered relevant and promising.