PubMed Health⌕ Search

Biomedical subjects

J L Teillaud

Publications and source records attributed to J L Teillaud.

89 records · Page 5Linked to original sources
PubMed1988

Regulation of hybridoma B-cell proliferation by immunoglobulin-binding factor.

Immunoglobulin-binding factors (IBF), which are cytokines able to suppress the immunoglobulin production by normal and transformed B cells, have been tested for their ability to interfere with hybridoma B-cell growth. Coculture experiments performed in soft agar between hybridoma B cells and hybridoma T cells secreting IgG-BF indicated that IgG-BF act as a growth regulatory molecule able to inhibit strongly the development of hybridoma B-cell colonies; this cytostatic effect, which appeared not to be a direct cytotoxic effect, was confirmed when using semi-purified IgG-BF in both soft agar and liquid medium cultures of hybridoma B cells. Thus, IBF appear to act as both immunoregulatory and growth regulatory factors. Some of the molecular consequences of this dual effect and its possible role in certain B-cell lymphoproliferative diseases such as multiple myeloma are discussed.

Animals↗
PubMed1987

Software for the quantitative evaluation of in vitro monoclonal antibody production from ELISA data.

Software has been developed which permits the quantitation of monoclonal antibodies secreted by B cell hybridomas. This program does not require the user to enter a large number of complex parameters and can be easily used without any previous computer experience. It fits all the experimental and standard curves by determining overlapping linear domains using the linear least-squares method. The program is based on logarithmic interpolations for determining Ig concentrations comparing experimental samples to Ig concentrations in standards. It provides a complete print-out of the data with editing options and is written in BASIC EDEX 4.0 Commodore computer language. It permits the accurate quantification of minute amounts of monoclonal antibodies and can be used to detect the inhibitory or enhancing effects of lymphokines or cytokines on Ig secretion by hybridoma B cells.

Antibodies, Monoclonal↗
PubMed1987

A sensitive method for testing the effect of immunoglobulin binding factor on Ig secretion by hybridoma B cells.

A microtiter plate assay to detect the effect of immunoglobulin binding factor (IBF) on Ig secretion by hybridoma B cells is described. This technique permits the analysis of Ig secretion by only 200-400 hybridoma B cells using a PFC assay and an ELISA, and therefore increases the IBF/cell number ratio. This increase allows the detection of a strong IBF-mediated inhibitory effect on Ig secretion by hybridoma B cells, which is otherwise difficult to obtain reproducibly. The technique is simple, does not require any transferring step and is convenient, since it permits large numbers of samples to be tested. It can be extended to test IBF for all isotypes or other lymphokines that affect Ig secretion.

Animals↗
PubMed1987

Immunoglobulin G-binding factors (IgG-BF) inhibit IgG secretion by, as well as proliferation of, hybridoma B cells.

Mouse immunoglobulin G-binding factors (IgG-BF) produced either by activated T cells (ATC) or by hybridoma T cells (T2D4) directly inhibit the in vitro IgG secretion by hybridoma B cells. This inhibition affects IgG1, IgG2a and IgG2b and can be detected as early as after 2 h incubation of the cells with IgG-BF eluted from non-equilibrium pH gradient electrophoresis gels. Moreover, IgG-BF also exert a strong growth-inhibitory effect on hybridoma B cells without any detectable immediate cytotoxicity. These results provide an experimental basis to analyze the molecular and biological effects induced by IgG-BF on B cells.

Animals↗
PubMed1985

Fc receptors on cultured myeloma and hybridoma cells.

The specificity of the Fc gamma receptors on the X63.Ag8.653 nonproducing myeloma cell line has been examined for binding to IgG1-, IgG2a-, and IgG2b-containing antigen-antibody complexes. Complexes containing each of these subclasses bind, and the binding of each is inhibited by the others. Trypsin treatment did not inhibit the binding of any of these subclasses. Furthermore, the monoclonal anti-Fc receptor antibody 2.4G2 inhibits the binding of all three subclasses. These results, together with those of other investigators, suggest that there is a single FcR for IgG1, IgG2a, and IgG2b on mouse B cells which differs in its specificity from the macrophage Fc gamma R. This is confirmed by the fact that a mutant IgG2b myeloma protein which binds to the macrophage Fc gamma 1/gamma 2b receptor does not bind to the Fc gamma R on X63.Ag8.653.

Animals↗
PubMed1984

The identification of monoclonal class switch variants by sib selection and an ELISA assay.

Monoclonal antibodies can now be generated against a wide variety of antigens. However, a potentially useful monoclonal antibody may be of the wrong class or subclass for a particular task. Antibodies of the desired class can be obtained by identifying rare subclones in which the variable region has been rearranged to a new constant region. We describe here the use of sib selection and an enzyme-linked immunoassay (ELISA) for isolating such class and subclass switch variants from 2 IgM and 1 IgG3 producing hybridoma. The relative simplicity of ELISA assays makes it feasible to apply this approach to many different hybridomas. Since commercial affinity purified class and subclass specific antibodies are now available, the method can be used by any laboratory. Furthermore, the technique does not require that the switch variants express surface immunoglobulin and enriches for hybridomas secreting higher amounts of antibody.

Animals↗
PubMed1983

Monoclonal antibodies reveal the structural basis of antibody diversity.

Hybridoma technology has made it possible to introduce into continuous culture normal antibody-forming cells and to obtain large amounts of the immunoglobulin produced by each of these cells. Examination of the structure of a number of monoclonal antibodies that react with a single antigen has provided new information on the structural basis of the specificity and affinity of antibodies. Comparisons of families of monoclonal antibodies derived from a single germ line gene revealed the importance of somatic mutation in generating antibody diversity. Monoclonal antibodies that react with variable regions of other monoclonals allow the further dissection and modulation of the immune response. Finally, the continued somatic instability of immunoglobulin genes in cultured antibody-forming cells makes it possible to determine the rate of somatic mutation and to generate mutant monoclonal antibodies that may be more effective serological reagents.

Amino Acid Sequence↗
PubMed1982

Analysis of DR-like molecules on a marmoset Epstein-Barr virus-induced cell line using a monomorphic anti-human HLA-DR monoclonal antibody.

Mouse anti-HLA D region-related (DR) monoclonal antibodies have been found to cross-react with peripheral blood leukocytes from one primate species, the common marmoset (Callithrix jacchus). Immunoprecipitates of radioactively labeled cells extracted from a marmoset Epstein-Barr virus-induced cell line were analyzed by one- and two-dimensional gel electrophoresis and compared with the DR antigens of a human lymphoblastoid B cell line. Two chains of estimated molecular weights of 34 000 (alpha) and 28 000 (beta), similar to the human alpha and beta chains, have been observed in marmoset immunoprecipitates. Additionally, a set of spots located in the same area as the set of invariant spots found in human HLA-DR antigens is shown by two-dimensional gel electrophoresis. Thus, cross-reacting anti-human HLA-DR monoclonal antibodies could be used to analyze the expression and the structure of marmoset DR-like antigens.

Animals↗
PubMed1982

Monoclonal antibodies as a tool for phylogenetic studies of major histocompatibility antigens and beta 2-microglobulin.

The cross-reactivity of several monoclonal antibodies recognizing monomorphic determinants of human HLA-A, B, C, and DR antigens and human beta 2-microglobulin (beta 2m) has been studied on peripheral blood leukocytes in 24 different species. An monoclonal HLA-A-, B-, and C-specific antibody and four monoclonal HLA-DR-specific antibodies cross-reacted with cells from all the primate species tested. Furthermore, antibodies HLA-DR-specific were positive with peripheral blood leukocytes (PBL) from cows, goats, sheep, horses, and dogs. Two monoclonal beta 2m-specific antibodies, which were positive with PBL from certain primates, also reacted with cells from cows, goats, sheep, horses, and dogs. Two other beta 2-m-specific antibodies reacted only with PBL from chimpanzees. No reaction could be detected with all our reagents in other classes tested (birds, reptiles, amphibians, and Teleostei).

Animals↗