Lab.of General Immunology

Head - Petr G.Nazarov,
prof., MD, PhD

Currently the Department studies the immunological aspects of atherosclerosis, in particular, the sources of development of autoimmune responses to normal components of human blood serum. These studies showed C-reactive protein and serum amyloid P to be the factors activating non-specific defence reactions and inhibiting immune responses. In this case C-reactive protein realizes its immunobiological effects during the acute phase of inflammation, and serum amyloid P - during chronic processes. These proteins play an important role in coordination of non-specific and immune mechanisms in the course of defence reaction. They realize their effects by means of specific receptors localized in all leukocytes of blood, fibroblasts and hepatocytes as well as by means of switching on the feedback mechanisms in immunological network..

The study of C-reactive protein has also shown that it can neutralize some haemolytic toxins of bacterial origin and decrease toxic side effects of antimycotic antibiotics. At present the molecular basis of this phenomenon is studied for its possible employment in constructing new antitoxic preparations.

The investigations supervised by professor P. G. Nazarov are devoted to the immunology of the acute phase of inflammation, the acute inflammation phase proteins in particular: pentraxins (C-reactive protein, serum P component of amyloid, serum amyloid A, antiproteases alpha2 -macroglobulin and alpha1-antitripsin, complement proteins). Under investigation is the role of petraxins and other proteins of the acute phase of inflammation in immunoregulation and in immunopathology of atherosclerosis.

Investigation of pentraxins in the laboratory of general immunology resulted in detection and characterization of new ligands of CRP, including the exogenous and endogenous biologically active macromolecules. These investigations have shown that pentraxins play a protective antitoxic role at the early stages of infection, until the antibodies appear. The interaction of C-reactive protein with cytokines and its influence on the cytokine regulation of immunological reactions were studied. The pentraxins were proved to make a new class of inhibitors of cytokines.

The experimental data obtained show that C-reactive protein may be considered as an atherogenic factor and point to one of immunopathological mechanisms of the development of atherosclerosis. These data suggest a potential atherogenic danger of the elevation of the C-reactive protein level during inflammation episodes.

It has been recently shown that acetylcholine is also a pentraxin ligand. Their interaction is followed by weakening cardiotropic effects of acetylcholine.
One of the achievements was substantiation of a new conception of formation of an important factor of congenital immunity — a complement cascade. The primary functions of this ancient protein molecule cascade were proved to be reinforcement of the phagocytosis process and attraction of the migrating cells into the inflammation focus rather than elimination of the pathogenic microflora by lyses, as was formerly considered. A group of young gifted researchers is working to solve this and other actual questions of comparative immunology.