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Biomedical subjects

J de Maeyer-Guignard

Publications and source records attributed to J de Maeyer-Guignard.

At least 19 recordsLinked to original sources
PubMed1990

Alpha/beta interferons fail to induce antiviral activity from within the nucleus.

Electrophoretically pure murine alpha/beta interferons (IFN-alpha/beta) were microinjected directly into the nuclei of mouse L cells, each nucleus receiving 10 fl containing about 20,000 (IFN) molecules, an amount sufficient to induce the antiviral state when added to the culture medium of control cells. Three, six or 24 h after intranuclear delivery, the cells were challenged with vesicular stomatitis virus or Semliki Forest virus and the appearance of cytopathic effects was scored for each individual cell. The scoring of more than 1,000 intranuclearly injected cells in nine different experiments showed unambiguously that the intranuclear delivery of IFN-alpha/beta did not induce the antiviral state. The results argue strongly against the physiological importance of high-affinity nuclear binding sites for native IFN that have been recently described (V. M. Kushnaryov, H. S. MacDonald, G. P. Lemense, J. Debruin, J. J. Sedmak, and S. E. Grossberg, Cytobios 53:185-197, 1988). Together with earlier results of other groups describing the lack of IFN activity after intracytoplasmic injection (Y. Higashi and Y. Sokawa, J. Biochem. 91:2021-2028, 1982; G. Huez, M. Silhol, and B. Lebleu, Biochem. Biophys. Res. Commun. 110:155-160, 1983), these results lend weight to the hypothesis that the binding of IFN-alpha/beta to the plasma membrane receptor is sufficient to set into motion the complex mechanism of transmembrane signalling without requiring internalization of the bound IFN molecules.

Animals↗
PubMed1984

Inhibition of the T suppressor circuit of delayed-type hypersensitivity by interferon.

The effects of electrophoretically pure murine interferon (Mu-IFN-alpha beta) on the T suppressor pathway and on the T effector cell of delayed hypersensitivity (TDH) were investigated in BALB/c mice, in a 2,4-dinitrofluorobenzene (DNFB) contact-sensitivity model. Various T cell subpopulations, suppressor T cells of the afferent (Ts-aff) and efferent (Ts-eff) types, an auxiliary Ts (Ts-aux), as well as TDH were induced, and their function was assessed in transfer experiments. The results were as follows. At a dose of 5 X 10(3) U, IFN was shown to inhibit the Ts-aff response, when given to the donor animal shortly after induction of the Ts-aff subpopulation or when injected into the recipient 2 hr after spleen cell transfer. Pretreatment in vitro with IFN of the splenic cells to be transferred also abolished the Ts-aff response. Similar amounts of IFN were able to inhibit the generation of Ts-eff in the donor animals, whereas 10-fold-higher amounts were needed in vivo or in vitro to block the functional expression of Ts-eff in the recipient animal. Intravenous injection of IFN into recipients of Ts-eff on day 0 and 1 after sensitization inhibited the expression of the Ts-eff transferred 1 day before ear challenge. This suggests that the Ts-aux response required for the TDH suppression by Ts-eff is blocked by IFN. Secretion of a suppressor factor by Ts in vitro was not blocked by IFN. Treatment of the donor of suppressor factor-secreting Ts with IFN, however, blocked the induction of this Ts. The TDH were not sensitive to IFN even at amounts approximately 100 times higher than those used for the Ts inhibition in vivo as well as in vitro. These results demonstrate that low amounts of IFN may selectively block the suppressor pathway, because induction of these regulatory T cell subsets appears to be particularly sensitive to IFN. The exact mechanism of the IFN-mediated inhibition of Ts is not yet clear. The data suggest an important regulatory function of IFN in delayed-type hypersensitivity (DTH) reactions.

Animals↗
PubMed1981

Antiproliferative action of interferon on murine bone-marrow derived macrophages is influence by the genotype of the marrow-donor.

Mouse interferon inhibits proliferation of bone-marrow derived macrophages. The degree of inhibition of cell proliferation is significant influenced by the genotype of the bone marrow donor in that C57BL/6 cells are more resistant to the cell multiplication inhibitory effect of interferon than are BALB/c cells. These results thus confirm earlier observations using murine erythroid precursors as target cells and point to the existence of genes modulating the action of interferon.

Animals↗
PubMed1976

[The chromophore of blue dextran: a powerful ligand for the purification of interferon by affinity chromatography].

The chromophore of blue dextran can be used as ligand for affinity chromatography of interferon. One passage of a crude interferon preparation on a blue-dextran-sepharose column eliminates over 90% of the contaminating proteins. Desorption with an aqueous buffer of high molarity yields interferon preparations with specific activities of up to 4.5 X 10(6) units per milligram of protein and the recovery is 100%.

Animals↗
PubMed1973

Purification of mouse interferon by affinity chromatography on a solid-phase immunoadsorbent.

A solid-phase immunoadsorbent capable of binding mouse interferon has been prepared. Starting from crude tissue-culture material, interferon could be purified 1990 times in a single step of affinity chromatography. Overall recovery ranged from 55 to 103% with tissue culture and mouse-brain interferon; however, only 5% was obtained with Sendai virus-induced interferon from mouse serum.

Animals↗
PubMed1972

Interferon messenger RNA: translation in heterologous cells.

A viral inhibitor with the characteristics of mouse interferon is produced by avian and simian cells preincubated with RNA extracted from interferon-producing mouse cells. Similarly, RNA extracted from interferon-producing monkey cells induces a monkey interferon-like substance in avian cells and also in a line of simian cells, VERO, which normally lacks the capacity to produce its own interferon. In both cases, the RNA effect is inhibited by treatment of the receptor cells by cycloheximide, but not by actinomycin D. We conclude that interferon messenger RNA has been translated in the receptor cells. Thus, the production of interferon in heterologous cells can be used as a sensitive assay of interferon messenger RNA.

Animals↗
PubMed1969

Interferon synthesis in x-irradiated animals. IV. Donor-type serum interferons in rat-to-mouse radiation chimeras injected with Newcastle disease virus.

C(3)H/He mice were exposed to total-body X-irradiation of 1000 roentgens and received thereafter 10(7) xenogeneic Wistar rat marrow cells intravenously. In these rat-to-mouse chimeras, serum interferon-producing capacity upon injection of Newcastle disease virus was examined four weeks after grafting. Normal levels of circulating interferon were produced. The interferon, however, had the species specificity of rat interferon, being 20 times more active in rat embryo fibroblasts than in mouse embryo fibroblasts. Moreover, it behaved like rat interferon when filtered on Sephadex G-100 dextran gel, displaying one peak of activity in the 90,000 molecular-weight range and two incompletely separated peaks of 32,000 and 24,000, respectively, in the 30,000 molecular-weight region. The fact that the interferon is of the donor type in rat-to-mouse chimeras permits us to conclude that circulating interferon induced by New-castle disease virus is made in bone-marrow-derived cells.

Animals↗
PubMed1969

Gene with quantitative effect on circulating interferon induced by Newcastle disease virus.

Circulating interferon production, induced by Newcastle disease virus, is about seven times higher in C(57) Black mice than i Balb/c/Gif mice. A Mendelian analysis was carried out and circulating interferon production was measured in reciprocal F(1) hybrids, in the F(2) generation, in progeny of backcrosses of F(1) hybrids to either parent strain, and in second backcross progeny. The results indicate that a single, partly dominant, autosomal factor is responsible for the difference in circulating interferon production between both parent strains.

Animals↗
PubMed1967

Depression of circulating interferon response in Balb-c mice after urethan treatment.

Urethan, when given to female Balb/c mice, impaired the capacity of these animals to produce circulating interferon. The effect appeared rapidly after a single injection of either 1 or 1.5 milligrams of urethan per gram of body weight and was of short duration. The possibility that this inhibition of the production of interferon plays a role in the enhancement of viral leukemia by urethan should now be considered.

Animals↗