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Biomedical subjects

I L Chertkov

Publications and source records attributed to I L Chertkov.

At least 19 recordsLinked to original sources
PubMed1991

[Monoclonal antibodies to Rho(D)-antigen of the Rhesus system. Obtaining the EBV-transformed B-lymphoblastoid human cell lines secreting IgG-anti-D antibodies].

Human B-lymphoblastoid cell lines producing specific anti-D antibodies against Rh0(D) antigen have been established by EBV-transformation. The strong influence of the donor's immune status (serum titer of anti-D antibodies, intravenous booster injection prior to bleeding) is shown. The cell lines cloned by limiting dilution continuously produce anti-D antibodies in culture for 7 months or longer which is sufficient to support large-scale production of anti-D antibodies based on the cultivation of cryopreserved cells. Anti-D IgGl monoclonal antibodies obtained react with Rh-positive and Du cells but not with Rh-negative cells in serological tests. These human monoclonal antibodies could be useful in the prevention of Rh hemolytic disease of newborns.

Antibodies, Monoclonal↗
PubMed1991

[Human B-lymphoblastoid cell lines: optimal conditions for their procurement, selection, cultivation and cloning].

The protocol of Epstein-Barr virus (EBV)-induced transformation of B-lymphocytes from reripheral blood of normal humans has been described. The requirements for mononuclear EBV-infection and for selection, cultivation, and cloning of EBV-transformed cell lines have been investigated. Successful establishment of stable human immunoglobulin-producing cell lines from lymphocytes of immunized donors could be achieved following the protocol presented.

B-Lymphocytes↗
PubMed1991

[Transduction of oncogene RAS into antibody-producing hybridoma].

The effect of introduction by means of electroporation of protogene ras into cells of antibody-producing hybridoma was studied. Doubling time (TD) of transduced subclones, in which H-ras gene was expressed, proved to be 1.8-fold shorter as compared to the parent line. Other characteristics of the hybridoma (cloning efficiency, antibody production in vitro, the time of ascitic fluid appearance in mice and antibody titer in vivo) were not changed. Addition of 12-0-tetradecanoylphorbol acetate to the culture did not alter the growth parameters of H-ras transduced subclones.

Animals↗
PubMed1991

[Transduction of a marker gene (Neor) into precursor cells of the hematopoietic microenvironment].

The attempt of retroviral transfer of the bacterial Neor gene into stromal precursor cells able to transfer haemopoietic microenvironment and to long-term support of haemopoiesis in vitro and in vivo was made. The existence of marker gene in stromal cells was established by the method of polymerase chain reaction. The transduced stromal precursor cells create normal haemopoietic microenvironment. The data obtained would be important for the further investigation of proliferation and differentiation of stromal precursor cells.

Animals↗
PubMed1990

[Monoclonal anti-D antibodies: obtaining and use].

The principles of obtaining monoclonal antibodies against D-antigen of the rhesus system are overviewed. The lines secreting anti-D antibodies are characterized. The strategies for selecting the anti-D producers secreting the antibodies are substantiated, which are useful for developing rhesus-typing diagnostics and preparations to prevent Rh-sensitization.

Animals↗
PubMed1990

[Primary hemopoietic stem cell].

A complex of experimental original laboratory findings is presented to demonstrate a restricted proliferative potential of stem hemopoietic cells. Development of new methodologies to study primitive stem hemopoietic cells, i. e. the cells that are responsible for maintenance of continuous blood formation, allowed for confirming their existence, assessing their content in the hemopoietic tissue, determining the time and site of their embryonic origin, and for showing their limited capacity for regeneration. The obtained evidence is important for the understanding the mechanisms governing hemopoiesis.

Animals↗
PubMed1990

[Early hematopoietic stem cells (pre-CFU) studied in long-term culture of murine bone marrow].

A new category of primitive hemopoietic stem cells determined in murine bone marrow long-term culture (CFU-BMLTC) is described. The novel precursors give rise to hemopoietic colonies corresponding to "cobble stone" areas observed on the adherent cellular layer. The linear relationship between the colony number and the dose of bone marrow cells explanted in the culture has been discovered. Radiosensitivity of the new type of hemopoietic precursors in the bone marrow of adult mice is characterized by D0-1.28 Gy. CFU-BMLTC were also identified in 13-day mouse fetal liver. In contrast to CFUs the precursors described are less sensitive to extensive in vivo treatment with hydroxyurea. The data obtained have permitted the authors to make a conclusion on a higher status of CFU-BMLTC as compared to CFUs in the hemopoietic stem cell hierarchy.

Animals↗
PubMed1989

[Identification of primitive hematopoietic stem cells in mice by the limiting dilution method].

An absolute number of the primitive stem cells (PSC) providing for prolonged maintenance of hemopoiesis in culture was measured with the aid of the limiting dilution method. The number of the PSC was determined according to the magnitude of the "zero" class cultures, i. e. of the cultures in which CFUs could not be demonstrated after 5-8 weeks. The fitness of the method can be proved by the presence of the linear relations between the number of the explanted stem cells and the number of the PSC as well as by the passage of the regression curve through the origin of coordinates. The data on the content of the PSC functioning in vivo and in vitro turned out similar, amounting to about 100 cells per mouse femur.

Animals↗
PubMed1989

[Effect of endothelial and smooth muscle cells and the extracellular matrix produced by them on hematopoiesis].

The influence of endothelial and smooth muscle cells and their extracellular matrices on hemopoiesis in long-term bone marrow cultures was investigated. In contract to smooth muscle cells, the enrichment of adherent cell layer with endothelial cells led to the stimulation of hemopoietic cell and granulocyte-macrophage progenitor (CFU-GM) production. The extracellular matrices of both smooth muscle and endothelial cell origin also produced a stimulating effect on the culture, although they were not so effective as endothelial monolayers. The cultures from cryopreserved bone marrow could be established only with the help of endothelial cells or any types of extracellular matrices.

Cells, Cultured↗
PubMed1989

[Long-term culture of bone marrow from patients with PH'-positive chronic myeloid leukemia].

Long-term cultures from bone marrow of patients with chronic myeloid leukemia were obtained. The cultures were characterized by the reduced period of hemopoiesis. The enrichment of the adherent cell layer with endothelial cells or their extracellular matrix was not stimulative. The Ph'(+) malignant cells persisted in culture during the whole period of hemopoiesis. The data obtained indicate that the long-term bone marrow culture system is not suitable for the elimination of malignant cells from leukemic bone marrow.

Bone Marrow↗
PubMed1988

[The proliferative potential of hematopoietic stem cells (CFUs) during serial passage in irradiated mice as foci of ectopic hematopoiesis].

During serial passages of hemopoietic tissue as a whole ectopic hemopoietic site under renal capsule of irradiated mice gradual decrease of proliferative potential of CFUs has been observed. The results suggest that the most probable cause of such decline is random loss of precursor cells with high but limited proliferative potential during serial passages of hemopoietic tissue.

Animals↗