[Fragments of functional proteins in the primary culture of human erythrocytes].

According to previously reported data, the supernatant of a primary culture of human erythrocytes contains 33 hemoglobin fragments. An analysis of the supernatant of a 20% (v/v) suspension of human erythrocytes allowed us to identify additionally four peptides whose precursors are cytoplasmic beta-actin (two fragments), fructose diphosphate aldolase B, and an unknown protein, as well as the amino acids tyrosine and tryptophan. The composition and the content of the components of the supernatant did not depend on the age or blood group of donors. The dynamics of accumulation in the supernatant (20-80 min of incubation) of the 14 hemoglobin fragments with the most reliably reproducible contents was obtained. The content of six peptides increased more than twofold between 20 and 40 min of incubation: the maximum increase in concentration was observed between 40 and 80 min (140%). The level of peptides that had the maximum concentration at the end of incubation was about 1000 pmol/ml of sedimented erythrocytes. The biological effects of the peptides identified in the supernatant of erythrocytes involve the stimulation of proliferation and hemopoiesis, suppression of proliferation, a bactericide effect, etc. These effects indicate the physiological importance of peptide release by erythrocytes. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2008, vol. 34, no. 2; see also http://www.maik.ru.

[Proteolytic degradation of hemoglobin in erythrocytes results in formation of biologically active peptides]. / Proteoliticheskaia degradatsiia gemoglobina v éritrotsitakh privodit k obrazovaniiu biologicheski aktivnikh peptidov.

The formation of biologically active hemoglobin fragments in human erythrocytes was studied. The structures of 33 peptide products of intraerythrocytic hemoglobin cleavage were determined. Based on an analysis of these sequences, a model of the stepwise degradation of the hemoglobin alpha- and beta-chains was suggested. The processes of peptide formation in a cell-free erythrocyte lysate system were studied. The involvement of an enzymatic complex of the cell membrane fraction was demonstrated. It was found that the cells of a surviving human erythrocyte culture secrete short (of 5-20 amino acid residues) peptides, and the structures of 36 peptides were determined. The dynamics of peptide secretion was investigated, and preliminary data on the energy-dependence of this process were obtained. Based on the experimental results, a model describing erythrocytes as an endocrine gland was suggested.

[Biologically active peptide fragments of functional proteins produced by proteolysis in vitro]. / Biologicheski aktivhye proteoliticheskie fragmenty funktsional'nykh belkov, poluchennye in vitro.

Over 100 various peptides were identified as a result of numerous studies of in vitro proteolytic digestion of some proteins and tissue preparations. Many of them exhibit wide spectra of biological effects, which are similar to those described for some groups of endogenous peptide bioregulators. The possibility of in vitro modeling of endogenous processes of proteolytic digestion of proteins that provides biologically active peptides is discussed.

[Changes in the intraerythrocytic proteolysis of human hemoglobin in lymphogranulomatosis]. / Izmeneniia vnutriéritrotsitarnogo proteoliza gemoglobina cheloveka pri limfogranulematoze.

The data obtained on red cell hemolysates from 16 patients with Hodgkin's disease varying in age, sex, the disease stage and histology, time since the diagnosis served the basis for comparative evaluation of endogenic intraerythrocytic hemoglobin proteolysis and relevant products. The results show that Hodgkin's disease brings about a 10-15-fold increase in the quantity of accumulated hemoglobin alpha-chain fragments.

[The acceleration of experimental influenza B infection under the influence of gangliosides]. / Uskorenie éksperimental'noi grippoznoi B infektsii pod vliianiem gangliozidov.

The influence of mono-, di-, and trisialogangliosides on the dynamics of influenza B virus reproduction in human embryo fibroblast (HEF) cell culture and human diploid cells was established. The cells were treated with neuraminidase of non-cholera vibrio for removal of natural receptors followed by treatment with gangliosides. Virus reproduction was assessed by infectious titres for chick embryos and HA test of the culture fluid at certain intervals. Gangliosides restored influenza virus reception and enhanced the infectious process as compared with the controls. Treatment with gangliosides of HEF culture of low sensitivity increased its susceptibility to virus markedly.