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Journal of General Virology | 1979

Physico-chemical Characterization and Partial Purification of Mouse Immune Interferon

Juana Wietzerbin; Simon Stefanos; Miguel A. Lucero; Ernesto Falcoff; Judith A. O'Malley; Eugene Sulkowski

Mouse immune (type T) interferon was produced from suspensions of spleen cells (1 X 10(7) cells/ml) treated with 3 micrograms/ml of phytohaemagglutinin. The crude interferon was chromatographed on four sorbents with varying affinities, namely concanavalin A-Sepharose, Affi-Gel 202, Blue Sepharose CL-6B and Phenyl-Sepharose CL-4B. With each of these the interferon activity was observed to have considerable heterogeneity. By means of affinity chromatography, mouse immune interferon was purified 100 to 200 times with concomitant complete recovery of activity.


Virology | 1980

Antiviral response and induction of specific proteins in cells treated with immune T (type II) interferon analogous to that from viral interferon (type I)-treated cells

Ara G. Hovanessian; Eliane F. Meurs; Odile Aujean; Catherine Vaquero; Simon Stefanos; Ernesto Falcoff

Abstract Treatment of mouse L929 cells with immune T (type II) interferon resulted in the induction of two double-stranded (ds) RNA-dependent enzymes which have been described previously in viral (type I) interferon-treated cells: pppA(2′p5′A)n synthetase and protein kinase(s). The induction of these enzymes by T interferon was blocked by anti-T but not by antiviral interferon serum. The kinetics of the development of the antiviral state along with a comparison of the levels of pppA(2′p5′A)n synthetase and protein kinase in T and viral interferon-treated cells were investigated. In addition, [ 35 S]methionine-labeled extracts from control, T, and viral inteferon-treated cells were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and two-dimensional gel electrophoresis. Extracts from cells treated with either type of interferon were found to contain several identical proteins, of estimated molecular weights 60,000, 88,000, and 120,000, which were absent or found at much lower levels in preparations from control cells. The newly synthesized proteins can be partially purified by chromatography on columns of poly(I)·poly(C)-Sepharose, thus providing a convenient method for their further characterization. These results show that treatment of cells with T interferon results in the induction of intracellular events identical to those observed in viral interferon-treated cells.


Antiviral Research | 1982

Synergistic activities of type I (α, β) and type II (γ) murine interferons

Aurelio Zerial; Ara G. Hovanessian; Simon Stefanos; Kris Huygen; Georges H. Werner; Ernesto Falcoff

Type I (alpha, beta) and type II (gamma) murine interferons are able to potentiate each other with respect to the inhibition of encephalomyocarditis (EMC) virus and of herpes simplex virus type 1 (HSV-1) multiplication in a murine cell line (DBT). Examination of two double-stranded RNA-dependent enzymes in DBT cells, the 2-5A synthetase and the 67,000 MW protein phosphokinase indicates that mixed interferon preparations act synergistically at least with respect to an increase in the activity of the former enzyme. The results obtained with gamma interferons of different origin and of different specific activity suggest that interferon itself, rather than the lymphokines present in the interferon preparations, is responsible for the synergistic effect.


Journal of General Virology | 1980

Production of antibodies against mouse immune T (type II) interferon and their neutralizing properties.

Simon Stefanos; Liliane Catinot; Juana Wietzerbin; Ernesto Falcoff

An antiserum to immune T-type mouse interferon was prepared in rabbits by repeated injections of interferon, induced by phytohaemagglutinin (PHA) in mouse spleen cells and purified to 1 X 10(5) units/mg protein. The antiserum neutralized mouse interferons synthesized in vitro in response to several T mitogens and Brucella organisms, and also the type II interferon present in the serum of BCG-sensitized mice after an injection of the specific antigen, tuberculin. All these interferons are thus antigenically related; they are also all unstable at pH 2. In contrast, the antiserum did not neutralize interferons induced by West Nile virus (WNV) and Newcastle disease virus (NDV) in vitro, or by lipopolysaccharide and Brucella organisms in vivo; all these interferons are stable at pH 2. It also failed to neutralize a non-glycosylated virus interferon prepared in the presence of tunicamycin.


Annals of the New York Academy of Sciences | 1980

PROPERTIES OF MOUSE IMMUNE T‐INTERFERON (TYPE II)

Ernesto Falcoff; Juana Wietzerbin; Simon Stefanos; Miguel A. Lucero; Claude Billardon; Liliane Catinot; Françoise Besançon; Helmut Ankel

I would like, if I may, to start my talk on T-interferon by attempting to justify the reason for this nomenclature. We used the term “Immune Interferon” for the first time in 1972’ to define the types of interferon (IF) exclusively produced in immunocompetent cells stimulated by specific antigens or by nonspecific stimulants like mitogens and lectins. The term “immune-interferon” is frequently used in the literature. The work done in this field by our group and other l abora t~ r i e s~ -~ has led to the conclusion that there are two different types of immune-interferons: firstly, those induced by stimulants dependent on B lymphocytes-acid-stable, antigenically related to viral IF-and secondly, IFs induced by T-lymphocyte stimulants: these are acid-unstable and antigenically distinct from viral IF (FIGURE 1). We shall refer to these interferons as Type B and Type T, taking into account inducer selectivity exclusively. Youngner introduced another very popular nomenclature for antigeninduced IF. which he defined as acid-unstable and antigenically distinct from viral I F he called it Type I1 i n t e r f e r ~ n . ~ Immune and Type I1 interferon are often synonymous in the literature. However, according to the criteria we have just defined (antigenic properties and stability at acid pH) these terms cannot be used synonymously. As a function of these two criteria we therefore consider that among immune interferons a distinction must be made between Type T. which is similar to Youngner’s Type 11. and Type B, which shares some of the characteristics of viral interferon. This is schematized in FIGURE 2. We do not claim here to suggest a final classification for immune-induced IFs, for I think it is still too early to achieve this. The present comments simply aim to avoid the confusion caused by the use of the term “immune-interferon” as a synonym for Type I1 interferon. The T-interferon prototype used in our research over the past few years was prepared by PHA stimulation of mouse splenocytes. since, as you know, PHA stimulates T lymphocytes. The method has been optimalized and at the present time we are able to prepare considerable quantities of this interferon. The crude preparation has a


Cellular Immunology | 1980

Immunosuppressive properties of purified immune T-interferon

Miguel A. Lucero; Juana Wietzerbin; Simon Stefanos; Claude Billardon; Ernesto Falcoff; Wolf H. Fridman

Abstract Purified T-interferon (specific activity 1–2 × 10 5 units/mg), induced by PHA, inhibits antibody synthesis in vitro to sheep red blood cells (SRBC). Upon fractionation on different chromatographic sorbents (Con A-Sepharose, Blue Sepharose CL-68), the inhibitory activity could not be dissociated from antiviral activity. The kinetics of action of T-interferon on antibody synthesis show that it interferes with the early events of lymphocyte activation. Inhibition was maximum when T-interferon was added 6 hr before or together with antigen but significant effect was still obtained when T interferon was added up to 24–48 hr after antigens. These kinetics were similar to those obtained with viral interferon. Pretreatment of T-interferon for 24 hr at pH 2 destroyed both the antiviral and immunosuppressive activities. A large increase in the number of anti-SRBC plaque-forming cells was observed when crude T-interferon preparation was added 24–48 hr after SRBC. However, purified T-interferon did not display any enhancing activity at any time of addition and always inhibited the plaque-forming cell response to SRBC. When titrated on the basis of antiviral activity no quantitative difference in the inhibition of antibody synthesis could be found between purified T-interferon and viral interferon.


Immunopharmacology and Immunotoxicology | 1985

SLO4, A New Interferon Inducer Isolated from Klebsiella Pneumoniae and Escherichia Coli

Simon Stefanos; C. Vanderhoven; Juana Wietzerbin; R. Falcoff; Y. Page

A product isolated from Klebsiella pneumoniae and Escherichia coli, coded SLO4, has been shown to be effective in endogenous interferon induction in vivo in mouse when administered IP or IV, and in vitro with human leukocyte cultures. In these two systems induced interferon was defined. The inducer has not yet been characterized but seems not to belong to any components known to be interferon inducers such as viral particles, nucleic acids or endotoxins. An analytical study will be carried out to specify the constitution of this interferon inducer.


Cell Biology and Immunology of Leukocyte Function | 1979

CHARACTERIZATION OF IMMUNE INTERFERON INDUCED IN NUDE MICE SPLEEN CELLS

Juana Wietzerbin; Simon Stefanos; Rebeca Falcoff; Miguel A. Lucero; Liliane Catinot; Ernesto Falcoff

Publisher Summary This chapter describes the characterization of immune interferon induced in nude mice spleen cells. Interferons are antiviral proteins synthesized by many kinds of somatic cells in response to viral infection. Specific antigens and T and B lymphocytes stimulants are also able to induce the production of interferon but only in immunocompetent cells. This immune induced interferon, which appears in the course of many immunological events at the same time as other lymphokines, may play a part in regulating the immuno response. In an experiment described in the chapter, it was found that when the total population of spleen cells from nude mice was fractionated on a column of Degalan beads coated with anti-mouse immunoglobulins that removed the Ig + cells, the excluded cell population constituting a fraction enriched in theta-positive cells failed to produce a significant amount of interferon when incubated with PHA. The interferon titer was enhanced when Degalan-excluded cells were added to the total spleen cell population from nude or Balb/C mice. The enhanced phosphorylation of the 67000 MW protein indicates that pretreatment with PHA-interferon induces in the cells a protein kinase system similar to that induced by viral interferon.


Journal of interferon research | 1989

Characterization of Human Interferon-γ Receptor Purified from Placenta

Simon Stefanos; Yong Ho Ahn; Sidney Pestka


European Journal of Immunology | 1986

Control of Ia antigen expression on phagocytic cells of the thymic reticulum by interferon-gamma and prostaglandins

Martine Papiernik; H. Dombret; Simon Stefanos; Juana Wietzerbin

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