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J F Delagneau

Publications and source records attributed to J F Delagneau.

At least 19 recordsLinked to original sources
PubMed1993

[Simultaneous multiple immunoassays: current data].

Help in diagnosis and disease monitoring requires more and more tests with fast results: To satisfy these requirements, two approaches are possible: full automation and rapid data processing, and multiple simultaneous assays. Simultaneous assays are already commercially available with different kinds of labels (radioisotopes, enzymes, fluorophores, etc). First applications concerned simultaneous determinations of two analytes (eg FSH-LH) by two different radioisotopic (125I, 57Co), or fluorescent (Eu = Sm ...) labels. Recently, assays were described which permit simultaneous determination of more than ten analytes (membrane immunoprinting). Techniques can be classified in three groups: i) one reaction site and a single kind of signal; ii) several reaction sites and one kind of signal; iii) several reaction sites and several kinds of signal. Main applications concern antibodies, antigens and haptens determination. Simultaneous assays will be soon associated with new solid phases and detection modes in fully integrated systems, leading to simultaneous multiple determinations in a single drop of blood.

Binding Sites↗
PubMed1990

Criteria for the selection of a solid phase to be used in immunoassays.

Heterogeneous immunoassays are very sensitive and only limited in terms of performance by non specific binding. They require separation of free from bound fractions and concomitant use of a solid phase coated with an immunoreactive component (i.e. immunosorbent). The improvement of these key immunosorbents is crucial and involves a great deal of expertise and capabilities. Specifications differ according to procedure (e.g. capture or competitive assay). Each routinely used solid phase, such as polystyrene wells, porous membrane or dispersible microbeads, presents specific performance characteristics, advantages, and drawbacks. Among the tasks to be implemented are optimization of the spatial orientation of immunological reagents, selection of the surface neutral hydrophilic support, acceleration of reactions by increasing the reactive surface area of the supports, streamlining and simplification of procedural steps. These various aspects are abundantly described and emphasized here.

Acrylamide↗
PubMed1989

Rapid diagnosis of cytomegalovirus by indirect immunofluorescence assay with monoclonal antibody F6b in a commercially available kit.

Anti-human cytomegalovirus (CMV) monoclonal antibody (MAb) F6b produced by clone 95/12 was used for the rapid diagnosis (16 to 24 h) of CMV isolates in 308 clinical specimens and compared with classic isolation. MAb F6b gave 100% correlation with isolation. When this MAb was used for direct diagnosis with 212 urine and bronchoalveolar specimens, detection of CMV varied from 50 to 75% compared with viral isolation.

Antibodies, Monoclonal↗
PubMed1986

The influence of the type of immunosorbent on rabies antibody EIA; advantages of purified glycoprotein over whole virus.

Two types of in vitro assay (enzyme immunoassay and sero-neutralization test) for the titration of rabies antibodies were used to assay sera from mice and humans immunized with cell culture vaccines or neural tissue vaccines. Enzyme immunoassays (EIA) were performed in plates sensitized with whole virus, purified glycoprotein or purified nucleocapsid. Neutralizing antibody titres were determined by the rapid fluorescent focus inhibition test (REFIT) and by an in vitro seroneutralization test including a rapid enzyme immunotitration of intracellular antigens (REITICA). The results obtained with sera of immunized mice and humans showed that (1) cell culture vaccines mainly induced the synthesis of antiglycoprotein neutralizing antibodies; and (2) neural tissue vaccines induced a high synthesis of antinucleocapsid non-neutralizing antibodies and a more or less important synthesis of antiglycoprotein antibodies depending on the origin of the tissue used for their preparation. Consequently, it was emphasized that when using EIA, the antibody titration must be run in glycoprotein-coated plates rather than in whole virus-coated plates to appreciate correctly the immunizing potency of a rabies vaccine, especially neural tissue vaccine.

Animals↗
PubMed1984

Monoclonal antibodies to human IgE: utilization for total IgE quantification and estimation of allergen specific IgE antibodies.

Spleen cells from Balb C mice immunized with purified Yu human myeloma IgE were fused with NS-1 mouse myeloma cells. After initial EIA screening for antibody-secreting cells, 20 hybrids were further characterized for cell growth, ascites production, antibody titer, specificity and affinity. Immunoglobulins purified from ascites fluid obtained from selected clones were labelled with beta-galactosidase. Combinations were made using either antibodies as capture and as conjugate against calibrated human IgE plasma samples. The combination of monoclonal anti IgE X b 10-22 as a capture antibody and X b 6-16 as a conjugate gave the best sensitivity and slope in EIA. It was successfully used in a sensitive two-step-enzyme-immunoassay for total IgE. The X b 6-16 conjugate was also assayed for the detection of allergen specific IgE antibodies. The results presented and discussed indicate that monoclonal antibodies could favourably substitute for polyclonal anti IgE antibodies in such assays.

Allergens↗
PubMed1980

Use of an enzyme immunoassay with protein A for rabies antigen and antibody determination.

The rabies antigen quantitation reported here is based on the principle of an enzyme immuno micro assay (EIA) using antigen coated polystyrene microtiter plates. In a first step antibodies of known specificity are partially blocked by the antigen to be titrated; in a second step the free remaining antibodies are determined by EIA. Antirabies vaccines, purified virus or rabies glycoprotein were assayed by that micro-method in comparison with the double neutralization test in tissue culture. Moreover, we report results obtained by EIA on the rate of antigen bonding to a solid carrier in order to prepare immunoadsorbents and the usefulness of EIA to monitor specific immunoglobulin elution.

Antibodies, Viral↗
PubMed1978

An RNA polymerase activity in purified rabies virions.

An RNA polymerase activity has been demonstrated in purified rabies virions. Efficiency of the reaction is low since the rate of incorporation was equal to 3 to 5 pmol of uridine per hour, per mg of protein. As with other mammalian rhabdoviruses the optimal temperature was 31 degrees C. Unlike vesicular stomatitis virus, manganese could be substituted for magnesium as a divalent cation, at an optimum concentration of 10 to 20 mM.

DNA-Directed RNA Polymerases↗
PubMed1978

Transcriptional mapping of rabies virus in vivo.

Synthesis of the proteins of rabies virus was studied in hamster cells infected with UV-irradiated virus. The UV target size of genes L, N, M1, and M2 was measured during primary transcription. Except for N, the target size of the remaining genes was considerably larger than that of their physical sizes. The data fit the hypothesis that four genes occupy a single transcriptional unit and that transcription of rabies virus proceeds in the order N, M1, M2, and L.

Cell Line↗