[Immunoglobulin G monoclonal human anti-rhesus Rho(D) to prevent rhesus-incompatibility]. / Immunoglobulin G monoklonal'nyi chelovecheskii anti-rezus Rho(D) dlia profilaktiki rezus-nesovmestimosti.

RhD immunisation which follows pregnancy can be prevented by administration to the rhesus-negative mother of 20 micrograms anti-D immunoglobulin per 1 ml of D-positive fetal red cells in the maternal circulation. With the aim of substitution of polyclonal anti-D with monoclonal one we developed human-mouse cell lines producing anti-RhD IgG1 by fusing EBV-transformed human immune lymphocytes with murine myeloma. After several clonings and passages the EBV genome was eliminated from the cell lines. The antibodies were purified from culture supernatants using protein A affinity chromatography and tested for sterility, virus contamination, pyrogenecity, toxicity and DNA content. The monoclonals were compared with the standard polyclonal anti-RhD in in vitro and in vivo assays. In antibody-dependent cell cytotoxicity (ADCC) 2 of 4 studied monoclonals promoted greater RBS lysis than polyclonal anti-D at equivalent concentrations. Detection of binding site number of monoclonals anti-D revealed about 10,000/RBS D-determinants on DCe/dce erythrocyte which agrees with the data for polyclonal anti-D. Best in ADCC monoclonal anti-D sharply increased human autologous 51Cr-labelled rbc sensitised in vitro as well as accelerated clearance of RhD RBS from circulation of Rh-negative volunteers injected with 150 micrograms monoclonal anti-D. After clinical trial using of monoclonal anti-D is permitted in Russia.

[Monoclonal anti-D immunoglobulin for prevention of hemolytic disease of the newborn]. / Monoklonal'nyi anti-D immunoglobulin dlia profilaktiki gemoliticheskoi bolezni novorozhdennykh.

Stable human-mouse heterohybridoma producing human monoclonal anti-D IgG1 has been derived by fusing Epstein-Barr virus (EBV) transformed human immune lymphocytes with mouse myeloma. The absence of EBV DNA in heterohybridoma was demonstrated by the polymerase chain reaction. The antibody was purified by affinity chromatography on protein A Sepharose and tested for sterility, pyrogenicity and toxicity according to the Pharmacopoeia XI and the ability to clear from circulation RhoD-positive red cells. The time of clearance of sensitized RBC was about 3 hrs. Since it is believed to be an association between the rate of RBC clearance by anti-D and the ability of the antibody to suppress the immunization, the monoclonal immunoglobulin may prove suitable for immunoprophylaxis of RhD hemolytic disease.

[Anti-Rho[D] antigen monoclonal antibodies. II. Serological characteristics of monoclonal IgG1 antibodies]. / Monoklonal'nye antitela k Rho[D]-antigenu sistemy rezus. II. Serologicheskaia kharakteristika monoklonal'nykh IgG1-antitel.

Four IgG1 monoclonal antibodies (MoAbs) to the Rh antigen D, produced by stable Epstein-Barr virus transformed B-lymphoblastoid cell lines were assessed in different serological tests. Their suitability in blood group typing was shown in antiglobulin, enzyme or albumin methods. The specificity and activity of MoAbs was tested with a panel of red cells of various Rh-phenotypes. The supernatants of all four lines showed anti-D specificity and ability to react with Du red cells. Mean level of MoAbs concentration was near 10 micrograms/ml. These human anti-D MoAbs proved to be useful D-typing diagnostic reagents.

[Monoclonal antibodies to Rho(D)-antigen of the Rhesus system. Obtaining the EBV-transformed B-lymphoblastoid human cell lines secreting IgG-anti-D antibodies]. / Monoklonal'nye antitela k Rho(D)-antigenu sistemy Rezus. Poluchenie EBV-transformirovannykh B-limfoblastoidnykh kletochnykh linii cheloveka, sekretiruiushchikh IgG-anti-D antitela.

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.

[Human B-lymphoblastoid cell lines: optimal conditions for their procurement, selection, cultivation and cloning]. / B-limfoblastoidnye kletochnye linii cheloveka: optimizatsiia uslovii polucheniia, selektsii, kul'tivirovaniia i klonirovaniia.

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.

[Monoclonal antibodies with anti-N specificity]. / Monoklonal'nye antitela s anti-N-spetsifichnost'iu.

In this article serologic characteristics of monoclonal antibodies with anti-N specificity is given. Antibodies are directed to homologous sequence of N-form of A glycophorine (group-specific N-antigen) and B glycophorine, expressed both on N- and on M-erythrocytes. Higher titre and avidity of monoclonal antibodies with anti-N specificity in relation to erythrocytes with N-phenotype make it possible to detect N-antigen in material subjected to expert evaluation.

[Monoclonal antibodies to the human group-specific antigen]. / Monoklonal'nye antitela k gruppospetsificheskomu antigenu cheloveka.

Serologic description of murine monoclonal antibodies (H-86/44 and H-86/50) which are capable to detect a membrane-connected form of human H antigen is given. The antibodies are notable for ability (H-86/44) to be absorbed by salivary H substance of ABH secretors i.e. to detect a soluble form of H antigen. Highly specific, highly active and standard anti-H reagents may be produced on the basis of the anti-H monoclonal antibodies obtained.

Hybrid resistance to parental bone marrow transplantation: adaptive modification of hemopoietic stem cell in a nonsyngeneic environment.

Defective growth of parental bone marrow in an F1 hybrid is associated with delay of the exponential growth phase of injected hemopoietic stem cells rather than with their rejection. This is demonstrated both by parental hemopoietic stem cell kinetics in the irradiated hybrid and by the increase in the number of spleen colonies with time after hemopoietic cell injection. After passage through an F1 hybrid the parental hemopoietic stem cells acquire ability for better growth in the same F1 host. This phenomenon, which we designated "adaptive modification of hemopoietic stem cells," is associated with the appearance, on their surface, of histocompatibility molecules carrying H-2 determinants of the recipient. Treatment of the modified cells with antiserum against the second parental strain abrogates the state of adaptive modification.

Effect of hemic cells on hybrid resistance.

Injection of various parental strain hemic cells reduces the ability of the F1 hybrid to resist growth of grafted hemopoietic tissue from the same parent strain. Such an effect can be exerted by cells from lymph nodes, spleen, bone marrow, or thymus, the peritoneal macrophages, and the peripheral blood leukocytes. Embryonic and adult liver cells or blood erythrocytes do not inhibit hybrid resistance. It is assumed that hemic cells inhibit hybrid resistance through an effect on the hemopoietic microenvironment. The mechanism of this effect cannot be considered the result of a graft-versus-host reaction since lymphoid cells which are "immune" or "tolerant" to the hybrid antigens possess inhibitory activity similar to that of intact lymphoid cells. The hybrid resistance inhibitory cells maintain the inability of "parent-in-F1 hybrid" type chimeras to express hybrid resistance for at least 2 months.