Pointing out some of important effects (Figure 1(a)), we would like to attract your attention to the ability of pyruvate and lactate to influence the processes of maturation of cells: stimulating the leukopoiesis and the erythropoiesis, to exert immunomodulatory, anti-inflammatory, antineurotoxic actions. Furthermore, small molecules can provide a protective effect on the membranes of the cells and blood vessels. Probably, the realization of this effect depends on neurogenic tone of blood vessels [16] . Indicates the ability of lactate to exercise fibrinolytic, antitoxic effects. The ability of lactate to exert such biological effects, is presumably related to the constitu-

ent hydroxyl group, which allows to take part in reactions of nucleophilic substitution.

In addition, we have observed the influence of lactate and pyruvate on antioxidant systems of the body, in particular―superoxide dismutase. Both act as an inhibitor of this enzyme, lactate and pyruvate are able to slow down the process of protecting cells from reactions of free radical oxidation, which constantly flow in the body, creating conditions for oxidative stress, damage molecules and structures.

Assessing the biological effects of lactate (Figure 1(b)), we found the ability to potentiate antibacterial activity, antiviral effect against arboviruses, rhinoviruses, picornaviruses and papillomaviruses. Antiviral activity of lactate is presumably associated with pH-dependent rearrangements in the structure of the virus: with decreasing pH, the virus loses its infectious activity, the connection of ribonucleoprotein with the protein matrix increases, which prevents the replication process [17] . Interesting was data that lactate was a promoter of insulin synthesis, thus clearly supporting the required amount of this hormone in the blood.

As for pyruvate (Figure 1(c)), it revealed the ability to act as a regulator of lipid metabolism, inhibitior of thrombocytopoiesis, to cause geroprotecting effect, to provide analgetic, anti-carcinogenic actions. Significantly, pyruvate participates in the process of tissue respiration, inhibits L- and D-forms of lactate dehydrogenase cytochrome. Pyruvate can be an oxidizer, an inhibitor of acylglycerols and a regulator of lipid metabolism, to increase cholesterol level and to reveal lipotropic effects.

The next step was to elucidate the potential biological activity of the antigens defined by the structural characteristics of the antigenic determinants of the ABO system (Figure 1(d)). To implement this task, we again used the computer program PASS. While studying the antigen A with N-acetylgalactosamine as a terminal monosaccharide and B antigen with galactose, obvious quantitative and qualitative differences of the identified effects and mechanisms for their realization were found.

An antigen determinant B has 106 pharmacological effects, performing with 311 molecular mechanisms of action. The number of side effects decreased to 16, metabolic activity increased, regulatory effect on gene expression still remains low, but increased in 1, 5 times comparing with A antigen. Probably this difference is the basis of selective affinity to antigens and foreign molecular, which appears in different incidence between 0 (I)-AB (IV) blood groups.

However, the results obtained by computer simulation are not the same as status vivo. Determinants of oligosaccharide chains of the ABO system, presented on the membranes of all cells of the body, might have multifunctionality and capacity to multiple effects on vital processes, maintaining the purity of our endoecology and providing a dynamic homeostasis along with other factors.

After examining in silico the potential of natural metabolites and antigenic determinants, we passed to the series of model experiments. Influence of pyruvate and lactate on the antigen-antibody complexes AB0 system was carried out considering changes of degree and speed of onset of agglutination. We found that the second blood group was the most sensible to the effects of pyruvate and lactate―the time of agglutination onset increased by 16% and 40% respectively. Antigen determinant A of the fourth blood group is more sensible to the influence of external stimules in contrast to the glycoprotein B. The degree of agglutination of the antigens of A (II)-B (IV) blood groups remained stable comparing with the control and amounted 4+. In general, we note that lactate influences more than pyruvate on the A and B determinants: formation of complexes antigen-antibody was longer (Figure 2(a)). Red blood cells A (II) and AB (IV) groups which have glycoprotein A on the surface, slower engage with the monoclonal antibodies than B (III) and AB (IV) blood groups on the membrane which have antigenic determinant agglutinogen B.

We can see a different effect of pyruvate and lactate in contacting with natural antibodies (Figure 2(b)). It is shown that the effect of lactate on whole blood system causes a modification of the immunoglobulins in plasma. There is a reduction in the degree of agglutination of the natural anti-A and anti-b antibodies with corresponding antigens compared to the control value.

Various impacts of pyruvate and lactate preincubation with monoclonal antibodies were discovered (Figure 2(c)). Lactate caused the deterioration of monoclonal antibodies recognizing antigenic determinants A and B A (II)-B (IV) blood groups, slowing down the formation of antigen-antibody complexes 20 and 15 times, as well as the severity of the degree of agglutination of 75%. Based on the obtained data, it can be assumed that incubation with lactate leads to structural and functional changes due to high chemical activity of the hydroxy acids,

the presence of a negative charge. We consider it is connected with non-enzymatic interactions. The time of agglutination of anti-A and anti-B monoclonal antibodies, preincubating with pyruvate decreased comparing with the control. In the interaction of anti-A and anti-B monoclonal antibodies with red blood cells of AB (IV) blood group-time interaction with the antigens A and B increased. The relative standard deviation (RSD) for each experiment result was evaluated (Table 1 and Table 2). Three series of model experiments on the effect of intermediates on isolated proteins―antigens, monoclonal and natural antibodies showed that the introduction of lactate in the antigen-antibody system is more active increasing the time of the onset of agglutination A glycoprotein with the corresponding antibody and reduce the degree of agglutination with natural anti-B antibodies in contrast to preincubation with pyruvate. Apparently, the differences can be explained with the peculiarities of their structure.

Using the method of flow cytometry, effects of pyruvate on the expression of antigenic determinants were revealed (Figure 3). The number of formed immune complexes increased in samples A (II) groups and decreased in B (III) and AB (IV) blood groups. The next step of our research is the visualization of antigen-antibody using fluorescent probes using laser scanning confocal microscopy.

Analyzing the spatial distribution of the fluorescence illumination intensity of fluorochrome in the complexes antigen-antibody, we notice a reduction in peak fluorescence in erythrocytes A (II) and (III) blood group after incubation with pyruvate compared with control erythrocytes (Figure 4). Apparently, pyruvate competes for the active reactive group antigens A and B with monoclonal antibodies labeled by fluorescein isothiocyanate, which is reflected in the change of the conformational structure of the protein molecule and the ability of antigens to form complexes antigen-antibody.