Monoclonal antibodies against the interferon receptor, with neutralizing activity against type I interferon

Abstract

A monoclonal antibody directed against the human interferon type I receptor (IFN-R), which recognizes the extracellular domain of the human IFN-R and has neutralizing capacity against the biological properties of human type I-IFN. Diagnostic applications for the monoclonal antibody also are provided.

Description

The interferons (IFN) constitute a group of secreted proteins which exhibit a wide range of biological activities and are characterized by their capacity to induce an antiviral state in vertebrate cells (I. Gresser and M. G. Tovey Biochem Biophys. Acta 516:231, 1978). There are three antigenic classes of IFN: alpha (.alpha.), beta (.beta.) and gamma. IFN.alpha. and IFN.beta. together are known as the type I interferon.

Natural type I human interferon comprises 12 or more closely related proteins encoded by distinct genes with a high degree of structural homology (Weissmann and Weber, Prog. Nucl. Acid. Res. Mol. Biol. 33:251, 1986).

The human IFN.alpha. locus comprises two subfamilies. The first subfamily consists of 14 non allelic genes and 4 pseudogenes having at least 80% homology. The second subfamily, .alpha.II or omega (.omega.), contains 5 pseudogenes and 1 functional gene which exhibits 70% homology with the IFN.alpha. genes (Weissmann and Weber 1986).

The subtypes of IFN.alpha. have different specific activities but they possess the same biological spectrum (Streuli et al. PNAS-USA 78:2848, 1981) and have the same cellular receptor (Agnet M. et al. in "Interferon 5" Ed. I. Gresser p. 1-22, Academic Press, London 1983).

The interferon .beta. (IFN.beta.) is encoded by a single gene which has approximately 50% homology with the IFN.alpha. genes.

The interferon a subtypes and interferon .beta. bind to the same receptor on the cell surface.

The interferon gamma (IFN gamma) is also encoded by a single copy, which has little homology with the IFN.alpha. and IFN.beta. genes. The receptor for IFN gamma is distinct from the receptor of the .alpha. and .beta. interferons.

For the purpose of the present invention the receptor of .alpha. and .beta. classes of IFN will be designated IFN-R. This represents natural type I receptor. The group of proteins forming natural interferon .alpha. will be designated IFN.alpha., and type I-IFN will represent both natural IFN.alpha., IFN.omega., and IFN.beta..

Despite the fact that interferon is a potent antiviral agent, there is considerable evidence to suggest, that many of the characteristic symptoms of acute virus diseases such as upper respiratory tract infections are caused by an overproduction of interferon alpha. Furthermore, IFN alpha has been shown to contribute to the pathogenesis of certain chronic virus infections in experimental animals and the available evidence suggests that this is also the case for certain human chronic virus diseases such as those due to measles virus.

The interferons .alpha. are also potent immunoregulatory molecules which stimulate polyclonal B-cell activation, enhance NK cell cytotoxicity, inhibit T-cell functions, and modulate the expression of the major histocompatibility complex (MHC) class 1 antigens, all of which are implicated in the induction of autoimmunity and in graft rejection. The abnormal production of interferon .alpha. is associated with a number of autoimmune diseases and inflammatory disorders including systemic lupus erythematosus (SLE), type I diabetes, psoriasis, rheumatoid arthritis, multiple sclerosis, Behcet's disease, aplastic anemia, the acquired immunodeficiency syndrome (AIDS) and severe combined immunodeficiency disease. The presence of interferon .alpha. in the serum of patients with systemic lupus is correlated with both the clinical and humoral signs of increased disease activity. The production of interferon .alpha. in HIV positive subjects is also highly predictive of disease evolution.

Administration of interferon .alpha. has been reported to exacerbate underlying disease in patients with psoriasis and multiple sclerosis and to induce a SLE like syndrome in patients without a previous history of autoimmune disease. Interferon .alpha. has also been shown to induce glomerulonephritis in normal mice and to accelerate the outset of the spontaneous autoimmune disease of NZB/W mice.

Interferon .alpha. is also produced during the course of graft-versus-host disease (GVHD) in parallel with the enhanced NK cell activity characteristic of systemic GVDH. Interferon .alpha. is the principal modulator of NK cell cytotoxicity and administration of interferon .alpha. has been shown to enhance the intestinal consequences of GVDH in normal mice.

The object of the present invention is to provide new antagonists against the biological activities of the human type I-IFN. These antagonists could be used for therapeutical, including prophylaxis purposes, in cases where the type I-IFN (IFN .alpha./.beta.) is abnormaly produced and when this abnormal production is associated with pathological symptoms. Such antagonists could also be used for the diagnosis of various diseases or for the study of the evolution of such diseases.

In order to define such antagonists, the inventors have taken into account the fact that the human natural type I-IFN is in fact constituted of a mixture of interferons (subspecies) and the fact that the composition of this association of different subtypes of interferons varies both quantitatively and qualitatively.

Some natural interferons, such as the ones secreted by Namalwa cells (Namalwa interferon) or leukocyte (leucocyte interferon) have been studied in detail (N. B. Finter and K. H. Fautes, Interferon 2, 1980, p. 65-79 I. Gresser Editor Academic Press; K. Cantell et al, Interferon 1, 1979 p. 2-25, I. Gresser Editor Academic Press) and were used by the inventors to define natural type I interferons.

In some pathological cases, like AIDS, interferons having some special properties have been described (O. T. Preble et al, Annals of New-York Academy of Sciences p. 65-75). This interferon involved in pathological cases like AIDS nevertheless binds to the same receptor, as described above.

One object of the present invention is to provide an antagonist of the type I-IFN, which would be able to inhibit or neutralize, to a determined extent, the biological properties of the human type I-IFN, that is to say, to neutralize in vivo a mixture of .alpha., .beta., .omega. subspecies.

Accordingly the inventors have defined antibodies, especially monoclonal antibodies, which have the property of being antagonists to the type I-IFN. These antibodies are directed against the human type I-IFN receptor.

The invention thus also concerns the use of the monoclonal antibodies for the preparation of pharmaceutical compositions, useful for the treatment of symptoms associated with the abnormal production of type I-IFN. These monoclonal antibodies are also appropriate for the preparation of diagnosis reagents.

A monoclonal antibody according to the present invention is directed against the human type I-interferon receptor (IFN-R) and is characterized by the following properties:

it recognizes the extracellular domain of the human IFN-R, and it has a neutralizing capacity against the biological properties of the human type I-IFN.

The ability to neutralize the biological properties of type I-IFN can be estimated as a function of the capacity of the monoclonal antibody to neutralize the antiviral activity of the type I-IFN. Such a test is relevant in order to determine whether the antibody assayed is included within the scope of the invention, although it is clear that the biological properties of type I-IFN are not limited to its antiviral properties. Detailed procedures are given in the examples in order to enable to perform such a test of the antiviral activity. The cells tested can advantageously be Daudi-cells, which affinity for the type I-IFN is well known. The main steps of such a test would consist in:

incubating a determined concentration of human cells responsive to human type I-IFN, with human type I-IFN in the presence of a determined concentration of monoclonal antibodies to be assayed, for a time sufficient to allow the formation of a complex between the monoclonal antibodies and the IFN-R of the human cells and/or between the type I-IFN and the IFN-R of the human cells; infecting the incubated cells with a determined virus, in a determined concentration, washing the cells, resuspending the cells in culture medium, incubating for a time sufficient to allow virus replication; lysing the cells; measuring the virus replication, or measuring the inhibition of the cytopathic effect.

The ability of the monoclonal antibodies of the invention to neutralize the biological properties of the human type I-IFN can be modulated as a function of the dose of antibodies used. Accordingly a 100% inhibition of the biological properties, or a partial inhibition can be obtained.

According to another embodiment of the present invention, the monoclonal antibodies directed against the human type I-IFN receptor, are further characterized by the fact that they are capable of inhibiting the binding of a human type I-IFN, to the human IFN-R.

A monoclonal antibody having the capacity to recognize the extracellar domain of the human IFN-R and capable of inhibiting the binding of the human type I-IFN to its receptor, can be selected by the following steps:

preincubating a determined concentration of purified monoclonal antibodies or a hybridoma culture supernatant containing monoclonal antibodies to be assayed, with human cells capable of harboring IFN-R; adding labelled human type I-IFN, in a determined concentration, to the above preincubated medium; incubating the medium containing the human cells, the monoclonal antibodies and the labelled type I-IFN for a time sufficient to allow an equilibrium to occur, between the monoclonal antibodies on the one hand and the type I-IFN on the other hand, with the cellular IFN-R; washing the cells; determining the formation of a binding complex between the human cells and the labelled type I-IFN by counting the amount of attached labelled type I-IFN.

Some of the monoclonal antibodies of the invention, have also the capacity to neutralize the antiproliferative properties of the human type I-IFN. This property can also be assayed on Daudi cells, by performing the following steps:

allowing cells to grow in presence of human type IFN and determined concentration of mAb; counting the cells in order to detect an inhibition of the antiproliferative effect of the human type I-IFN.

One property of a monocolonal antibody according to the invention resides in its capacity to recognize the extracellular domain of the human IFN receptor. This property of the monoclonal antibody can be assayed on human cells bearing the natural human receptor but also on the extracellular domain of a recombinant IFN-R such as expressed in a procaryotic cell, for instance in E.coli or a recombinant IFN-R such as expressed in a eucaryotic cell such as mamalian cell for instance a CHO-cell. This receptor can indeed present different properties, depending on the fact that it is produced in a procaryotic or eucaryotic cell and accordingly depending on the fact that the post-translational maturation occurred or not. The inventors interestingly showed that relevant assays, to evaluate the capacity of a monoclonal antibody according to the invention i.e. to recognize the cellular IFN-R, can be performed on a recombinant receptor expressed in mamalian cells. As a matter of fact, such recombinant receptor has the same properties as the cellular receptor, as far as its recognizing activity is concerned.

Monoclonal antibodies of the invention can be obtained against various forms of the receptor, including the complete receptor, a particular domain or a peptide characteristic of the aminoacid sequence of the receptor represented in FIG. 3 (SEQ ID NOS: 3-4).

Monoclonal antibodies of the invention can for example be prepared against the soluble form of the receptor. A hydrosoluble polypeptide corresponding to the soluble form of the INF-R is described on FIG. 2 (SEQ ID NOS: 1-2). According to the present invention, a soluble form of the IFN-R corresponds to a peptide or a polypeptide, capable of circulating in the body.

Other monoclonal antibodies according to the invention can also be prepared against a peptide comprised in the extracellular domain of the receptor as described on FIG. 2 (SEQ ID NOS: 1-2). An advantageous peptide corresponds for instance to the aminoacid sequence comprised between aminoacid 1 and aminoacid 229 of SEQ ID NO: 1 or 2. According to another embodiment of the invention, the antibodies can be prepared against a polypeptide modified by substitution of one or more amino acids, provided that antibodies directed against the non modified extracellular domain of the IFN-R, recognize the modified polypeptide or peptide.

Preferred monoclonal antibodies according to the invention are those which are of the IgG1 type.

Among the antibodies of the invention, an antibody which has the capacity of inhibiting the binding of the type I-IFN to its receptor is preferably characterized in that it inhibits the in vitro binding of human type IFN, to the human cellular IFN-R when it is co-incubated with cells harboring the hu-IFN-R, at a concentration of antibodies equal or inferior to 100 .mu.g/ml, preferably equal or inferior to 50 .mu.g/ml, advantageously inferior to 20 .mu.g/ml, more preferably in the range of approximately 0.5 to 2 .mu.g/ml.

The inventors have shown that the high affinity binding capacity of a monoclonal antibody is not sufficient to ensure that this antibody will be able to inhibit the binding activity of the human type I-IFN to the IFN-R. Nevertheless the high affinity binding capacity of the monoclonal antibody is necessary to investigate further the ability of the antibody to inhibit the binding of the type I-IFN to its cellular receptor.

Another monoclonal antibody is characterized in that it neutralizes in vitro the antiproliferative activity of human type I-IFN, on cells highly responsive to this human type I-IFN, for instance Daudi cells at a concentration in a range of 1 to 10 .mu.g/ml.

According to another embodiment a monoclonal antibody is also characterized in that it neutralizes in vitro the antiproliferative activity of human type IFN, on cells poorly responsive to this human IFN, for instance Ly28 cells, at a concentration in a range of 50 to 100 .mu.g/ml.

A particular group of monoclonal antibodies according to the invention is characterized in that it neutralizes the antiviral activity of the human type I-IFN, on cells highly responsive to this human type I-IFN, for instance Daudi cells at a concentration in a range of 1 to 50 .mu.g/ml, preferably 1 to 20 .mu.g/ml, for a concentration of type I-IFN in the range of 1 to 1000 units with reference to the international standard MRC 69/19.

Advantageously, the monoclonal antibody according to the invention is such that these antibodies do not bind to the human receptor for IFN gamma.

One particular antibody satisfying the requirements of the invention, is such as it is directed against an epitope on the amino-acid sequence comprised between amino-acid 27 and amino-acid 427 of the extracellular domain of the human IFN-R as represented on FIG. 2 (SEQ ID NOS: 1-2).

One particularly interesting monoclonal antibody according to the invention is the antibody designated 64G12 under n.degree. 92022605 which has been deposited at the ECACC (European Collection of Animal Cell Cultures Porton Down Salisbury, Wiltshire SP4 056, United Kingdom) on Feb. 26, 1992.

These antibodies may be prepared by conventional methods involving the preparation of hybridoma cells by the fusion of myeloma cells and spleen cells of an animal immunized beforehand with the peptide antigen, on the conditions such that the antigen against which the antibodies are formed is constituted by the extracellular domain of IFN-R or any polypeptide or peptide of this domain.

The hybridomas are constructed according to the protocole of Kohler and Milstein (Nature, 1974, 256: 495-497). For example the hybridomas are derived from the fusion of the spleen cells above described with NS1 mouse (BalbC) HGPRT.sup.- as myeloma cell.

A second procedure for the production of monoclonal antibodies according to the invention, consists in carrying out the fusion between B-cells of blood immortalized with the Epstein/Barr virus and human B lymphocytes placed beforehand in contact with the extracellular domain or a fragment thereof of the IFN-R, against which it is decided to form monoclonal antibodies. B-cells placed in contact beforehand with the extracellular domain of IFN-R or fragment thereof against which it is decided to form monoclonal antibodies, may be obtained by in vitro culture contacted with the antigens, the recovery of the B-cells coated with these antigens being preceded by one or several cycles of stimulation.

The invention thus concerns human antibodies as obtained by carrying out the above procedure, having the above defined properties.

The invention also aims at providing a monoclonal antibody characterized in that the variable or complementary determining regions of its heavy and/or light chains are grafted on the framework and/or constant regions of a human antibody.

The invention further provides a composition having antagonist properties for the biological properties of the human type I-IFN, characterized in that it comprises monoclonal antibodies as defined above.

Accordingly the invention provides a pharmaceutical composition characterized in that it comprises monoclonal antobodies as defined above, together with an appropriate pharmaceutical vehicle.

The invention also concerns the use of a monoclonal antibody as defined above, for the manufacture of a drug for the treatment or profilaxis of a pathological state or symptoms associated with overproduction of type-I-IFN.

According to a first example, the antibodies can be used in a pharmaceutical composition, for the treatment of allograft rejection.

According to another example, antibodies of the invention are used as active principle in a pharmaceutical composition for the treatment of autoimmune and inflammatory diseases. Such diseases include systemic lupus erythematosus, type 1 diabetes, psoriasis, rheumatoid arthritis, multiple sclerosis, Behcet's disease, asplatic anemia, acquired immunodeficiency syndrome (AIDS), and severe combined immunodeficiency disease.

Treatment of acute virus diseases can also be performed with the antibodies of the invention. As example upper respiratory tract infections, chronic virus infections such as those due to measles virus, can be performed.

The antibodies of the invention can also be used for the in vitro diagnosis of the presence of the human type I-IFN receptor or cells.

Further details and additional information will arise from the description from the description of the examples and from the figures.

FIGURES

FIG. 1: binding of .sup.125 I-labelled monoclonal antibodies 34F10 and 64G12 to:

A: Daudi cells B: Ly28 cells

Briefly, 10.sup.6 cells were incubated for 2 hours at 4.degree. C. in presence of different amounts of the labelled antibodies diluted in RPMI medium containing 10% fetal calf serum (FCS). The cells were then washed 4 times in RPMI-1% FCS and counted for bound radioactivity. Nonspecific binding was mesured by incubation with a 100 fold exces of cold antibodies and substracted from total counts.

FIG. 2: nucleotide and corresponding amino-acid sequence (SEQ ID NOS: 1-2) of the extracellular domain of the human IFN-R

The monoclonal antibodies were produced against recombinant soluble forms of the human interferon alpha-beta receptor (IFN-R) synthetized in either procaryotic cells (E.coli) or a mammalian cell system (Cos cell). These soluble forms were based on the DNA sequence described in FIG. 2.

FIG. 3: nucleotide and corresponding amino-acid sequence (SEQ ID NOS: 3-4) of the human IFN-R.

EXAMPLES

Example 1

Synthesis of the Soluble Receptors Synthesis in E.coli

A fragment of DNA containing the sequence coding for the extracellular domain (amino acids 27 to 427) of the human INF-R (FIG. 2; SEQ ID NOS: 1-2), in which an extra-sequence coding for 5 histidyl residues was introduced just before the termination codon, was cloned in the expression vectors pKK233-2. This fragment was produced by the Polymerase Chain Reaction (PCR) and the resulting plasmids were sequenced to confirm both in-frame insertion with the Shine-Dalgarno sequence and the appropriate sequence coding for the receptor.

The poly-histidyl tail introduced into the recombinant protein enables it to be purified rapidly by affinity chromatography on a chelated nickel support (NTA column) as described previously (Hochuli E. et al, Bio/technology, 1988, 1321-1325).

The plasmid was introduced into the E.coli strain, JM105, and protein synthesis induced by addition of IPTG to the culture medium (pKK233-2, tac promoter).

Proteins were extracted from the bacterial pellet and the soluble receptor purified to homogeneity by affinity chromatography as described hereafter. This procedure yieled a protein that migrates as 2 bands around 50 kDa under reducing conditions and three bands under non-reducing conditions. The maximum concentration of the protein obtained by different procedures was approximately 20 .mu.g/ml.

The N-terminal sequence of the two proteins detected by gel electrophoresis has shown that both proteins are the expected fragment of the receptor.

Synthesis and Purification of an Unglycosylated Soluble Receptor: ##STR1##

Using the same PCR approach, we also constructed an expression vector coding for the IFN-R amino acid sequence 1-427, with an additional 5-histidyl residues at the C-terminus, inserted in expression vector pXMT-3. The exact nucleotide sequence of the insert was also confirmed.

The resulting plasmid was introduced by electroporation into Cos7 cells for transient expression and the recombinant protein was purified to homogeneity by affinity chromatography followed by ion exchange chromatography on mono-Q (Pharmacia) as described hereafter.

Purification of the Soluble IFN-R from Cos7 Cells ##STR2##

This purification yielded to a 76 kDa protein whose N-terminal sequence corresponds to the predicted receptor sequence with some heterogeneity in the processing of the leader sequence.

Example 2

Production of Monoclonal Antibodies Against the Interferon Type I Receptor

1) Production of the monoclonal antibodies

Mice were immunized by injection of recombinant soluble interferon (r sIFN-R) purified from E.coli or from a culture supernatant of Cos7 cells. Initially mice were injected both intraperitoneally and subcutaneously with the purified protein in complete Freund's adjuvant. Subsequently mice were injected once a week intraperitoneally with the purified proteins diluted in buffered saline solution. Ten micrograms of recombinant proteins were injected each time.

After the fourth injection, blood was collected and the presence of specific serum antibodies were tested by both ELISA and Western blot against the recombinant receptor. The strongest responders were then boosted with a total of 10 .mu.g of antigen half of which was injected intravenously and half intraperitoneally.

2) Cell fusion

Four days after boosting, spleen cells from the immunized animal were collected and fused to NS1 (mouse) (Balbc) HGPRT.sup.- myeloma cells according to the method described by S. Fazekas et al. (J. Immunol. Methods 35:1-32, 1980). Briefly, 5.times.10.sup.7 spleen cells were fused to 3.times.10.sup.7 myeloma cells in iml of polyethylene glycol solution and distributed in five 96 well plates on a peritoneal macrophage feeder layer in HAT (hypoxanthine, aminoprotein and thymidine) medium. This procedure was repeated 4 times as 20.times.10.sup.7 spleen cells were obtained from the immunized mouse. Screening for specific hybridomas was undertaken when large colonies were detectable in culture wells.

For the screening, presence of specific antibodies was determined by a direct ELISA method:

a) ELISA plates were coated overnight at 4.degree. C. with purified E.coli-expressed or Cos7 cell-expressed sIFN-R diluted in PBS. Plates coated with BSA were used to detect non specific binding, b) Plates were saturated by incubation with 3% BSA in PBS for 1 hour at 37.degree. C., c) Plates were incubated for 4 hours at room temperature with hybridoma supernatants diluted 1 in 4 with PBS-0.05% Tween 20, d) Bound antibodies were detected by a two step procedure, comprising a first incubation with goat anti-mouse biotinylated immunoglobulin followed by streptavidin-horseradish peroxidase complex (both from Amersham and diluted 1/1000 in PBS-0.05% Tween 20).

Positive antibody secreting hybridomas were passaged in 24 well plates on a spleen cell feeder layer and their reactivity was again checked by ELISA, and Western-blot.

3) Identification of reactivity to the natural interferon type I receptor

The reactivity of the monoclonal antibodies (mAbs) recognizing the recombinant SIFN-R was tested against the natural class I receptor expressed at the surface of Daudi cells, by membrane immunofluorescence. Briefly, 5.times.10.sup.5 Daudi cells were incubated in 100 .mu.l of culture supernatant of chosen hybridomas for 30 min at 4.degree. C. The cells were then washed 4 times in RPMI medium containing 1% BSA and further incubated with a diluted FITC labelled goat anti-mouse F(ab').sub.2 for 30 min at 4.degree. C. The cells were finally analyzed by flow cytometry after washing. One of the 35 tested antibodies produced against the E.coli recombinant receptor and 5 of the 6 tested antibodies produced against the COS recombinant receptor were found to recognize the natural receptor on the Daudi cells.

Cloning of these hybridomas was then performed by limiting dilution. The isotype of these mAbs was determined by an ELISA method using isotype specific antibodies. All 6 mAbs were found to be IgGp1 with kappa light chains. A summary of the reactivity of these 6 mAbs is given in Table 1.

Monoclonal antibodies were purified from culture supernatants by protein G chromatography.

TABLE 1______________________________________Reactivity of the anti IFN-R monoclonal antibodies Reactivity against the Reactivity against* recombinant receptor the cellular receptor______________________________________E. COLI COS ELISA Western ELISA Western immunofluorescence______________________________________34F10 + + + + +64G12 + + + + +63F664G2 - - + + +64D10 weak65D8______________________________________ *measured on Daudi cells

Example 3

Inhibition of the Binding of Interferon to Human Cell Lines

Inhibition of interferon binding to human cells was assayed as follows. 106 cells were preincubated at 4.degree. C. for 30 min with various dilutions of hybridoma culture supernatants or purified mAbs or with medium alone. .sup.125 I-labelled IFN alpha 8 or alpha 2 was added at the concentration of 100 pM and cells incubated for a further 2 hours at 4.degree. C. These incubations were performed in RPMI medium containing 20 mM HEPES pH 7.4 and 10% foetal calf serum (FCS). The cells were finally washed 4 times with RPMI--1% FCS and counted to determine bound radioactivity.

The mAb secreted by the hybridoma line 64G12 (latter named mAb 64G12) was shown in this assay to inhibit the binding of labelled IFN to the cells in a dose-dependent manner. 50% inhibition of binding to the Daudi cells (Burkitt lymphoma cell line; Klein et al., Cancer Research, 28:1300-1310, 1968) was obtained at a mAb concentration of 0.4 .mu.g/ml. The same inhibition was obtained with K562 cells (chronic myelogenous leukemia, Lozzio and Lozzio, Cell, 45:321-334, 1975) but 50% inhibition was obtained at 11 .mu.g/ml for HL60 cells (Promyelocytic leukemia, Collins S. J. et al., Nature, 270:347-349, 1977) and 60 .mu.g/ml for Ly28 cells (Klein G. et al. Int. J. Cancer, 10:44-57, 1972).

TABLE 2______________________________________The inhibition of binding labelled IFN alpha 2 tovarious cell lines by mAB64G12 Concentration of mAB which gives 50%Cell lines inhibition of binding______________________________________Daudi 0.4 .mu.g/mlK562HL60 11 .mu.g/mlLy28 60 .mu.g/ml______________________________________

The difference in the mAb concentration at which 50% inhibition of binding of IFN is obtained has been investigated by direct binding of .sup.125 I-labelled mABs 64G12 and 34F10 to the same cell lines and Scatchard plot analysis of the results. In the concentration range of 0.1 to 1.5 .mu.g/ml, a high affinity binding of the mAb 34F10 (.apprxeq.10 nM) was seen on all cell lines whereas a high affinity binding of mAB 64G12 was only detected on Daudi and K562 cells (FIG. 1).

Example 4

Inhibition of the Function of Type I Interferon

Functional inhibition of type I interferon by the purified mAb 64Gl2 was demonstrated in an antiviral assay on Daudi cells using either recombinant IFN alpha 2, IFN beta and IFN omega, or purified Namalwa and leucocyte interferons, and in an antiproliferative assay with recombinant IFN alpha 2.

* Antiviral Activity

An antiviral assay on Daudi cells was performed as described (M. Dron and M. G. Tovey, J. Gen. Virol. 64:2641-2647, 1983). Cells (0.5.times.10.sup.6 /ml) were incubated for 24 hours in the presence of interferon and antibodies. 10.sup.6 cells in 1 ml were then infected for 1 hour at 37.degree. C. with Vesicular stomatitis virus (VSV) then washed 3 times, resuspended in culture medium and incubated for 18 hours at 37.degree. C. Cells were then lysed by freeze-thawing and virus replication measured by titration of the supernatants on L929 cells. A dose-dependent inhibition of the antiviral activity of the various subtypes of type I IFN was demonstrated for the purified mAb 64G12.

For the antiviral assay with the Wish cells, cells were incubated for 24 hours with various concentrations of interferons in the presence of the mAbs prior to challenge with VSV. In this assay, the mAb 64G12 was demonstrated to block completely the antiviral activity of Leukocyte IFN (50 U/ml), recombinant IFN alpha 2 (50 U/ml) and interferon from the sera of AIDS patients (50, 75 and 150 U/ml).

* Antiproliferative Activity

For the antiproliferative assay, Daudi cells were seeded at a concentration of 10.sup.5 cells per ml in a 96 well plate in the presence of interferon and purified inhibitory or control antibody. Cells were then counted after 24, 48 and 72 hours with a Coulter counter and checked for viability by trypan blue exclusion. Purified mAb 64G12 demonstrated a dose-dependent inhibition of the antiproliferative activity of interferon alpha 2.

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#r Gly Met Asp Asn Trp# 70- ATA AAA TTG TCT GGG TGT CAG AAT ATT ACT AG - #T ACC AAA TGC AAC TTT 293Ile Lys Leu Ser Gly Cys Gln Asn Ile Thr Se - #r Thr Lys Cys Asn Phe# 85- TCT TCA CTC AAG CTG AAT GTT TAT GAA GAA AT - #T AAA TTG CGT ATA AGA 341Ser Ser Leu Lys Leu Asn Val Tyr Glu Glu Il - #e Lys Leu Arg Ile Arg#105- GCA GAA AAA GAA AAC ACT TCT TCA TGG TAT GA - #G GTT GAC TCA TTT ACA 389Ala Glu Lys Glu Asn Thr Ser Ser Trp Tyr Gl - #u Val Asp Ser Phe Thr# 120- CCA TTT CGC AAA GCT CAG ATT GGT CCT CCA GA - #A GTA CAT TTA GAA GCT 437Pro Phe Arg Lys Ala Gln Ile Gly Pro Pro Gl - #u Val His Leu Glu Ala# 135- GAA GAT AAG GCA ATA GTG ATA CAC ATC TCT CC - #T GGA ACA AAA GAT AGT 485Glu Asp Lys Ala Ile Val Ile His Ile Ser Pr - #o Gly Thr Lys Asp Ser# 150- GTT ATG TGG GCT TTG GAT GGT TTA AGC TTT AC - #A TAT AGC TTA CTT ATC 533Val Met Trp Ala Leu Asp Gly Leu Ser Phe Th - #r Tyr Ser Leu Leu Ile# 165- TGG AAA AAC TCT TCA GGT GTA GAA GAA AGG AT - #T GAA AAT ATT TAT TCC 581Trp Lys Asn Ser Ser Gly Val Glu Glu Arg Il - #e Glu Asn Ile Tyr Ser170 1 - #75 1 - #80 1 -#85- AGA CAT AAA ATT TAT AAA CTC TCA CCA GAG AC - #T ACT TAT TGT CTA AAA 629Arg His Lys Ile Tyr Lys Leu Ser Pro Glu Th - #r Thr Tyr Cys Leu Lys# 200- GTT AAA GCA GCA CTA CTT ACG TCA TGG AAA AT - #T GGT GTC TAT AGT CCA 677Val Lys Ala Ala Leu Leu Thr Ser Trp Lys Il - #e Gly Val Tyr Ser Pro# 215- GTA CAT TGT ATA AAG ACC ACA GTT GAA AAT GA - #A CTA CCT CCA CCA GAA 725Val His Cys Ile Lys Thr Thr Val Glu Asn Gl - #u Leu Pro Pro Pro Glu# 230- AAT ATA GAA GTC AGT GTC CAA AAT CAG AAC TA - #T GTT CTT AAA TGG GAT 773Asn Ile Glu Val Ser Val Gln Asn Gln Asn Ty - #r Val Leu Lys Trp Asp# 245- TAT ACA TAT GCA AAC ATG ACC TTT CAA GTT CA - #G TGG CTC CAC GCC TTT 821Tyr Thr Tyr Ala Asn Met Thr Phe Gln Val Gl - #n Trp Leu His Ala Phe250 2 - #55 2 - #60 2 -#65- TTA AAA AGG AAT CCT GGA AAC CAT TTG TAT AA - #A TGG AAA CAA ATA CCT 869Leu Lys Arg Asn Pro Gly Asn His Leu Tyr Ly - #s Trp Lys Gln Ile Pro# 280- GAC TGT GAA AAT GTC AAA ACT ACC CAG TGT GT - #C TTT CCT CAA AAC GTT 917Asp Cys Glu Asn Val Lys Thr Thr Gln Cys Va - #l Phe Pro Gln Asn Val# 295- TTC CAA AAA GGA ATT TAC CTT CTC CGC GTA CA - #A GCA TCT GAT GGA AAT 965Phe Gln Lys Gly Ile Tyr Leu Leu Arg Val Gl - #n Ala Ser Asp Gly Asn# 310- AAC ACA TCT TTT TGG TCT GAA GAG ATA AAG TT - #T GAT ACT GAA ATA CAA1013Asn Thr Ser Phe Trp Ser Glu Glu Ile Lys Ph - #e Asp Thr Glu Ile Gln# 325- GCT TTC CTA CTT CCT CCA GTC TTT AAC ATT AG - #A TCC CTT AGT GAT TCA1061Ala Phe Leu Leu Pro Pro Val Phe Asn Ile Ar - #g Ser Leu Ser Asp Ser330 3 - #35 3 - #40 3 -#45- TTC CAT ATC TAT ATC GGT GCT CCA AAA CAG TC - #T GGA AAC ACG CCT GTG1109Phe His Ile Tyr Ile Gly Ala Pro Lys Gln Se - #r Gly Asn Thr Pro Val# 360- ATC CAG GAT TAT CCA CTG ATT TAT GAA ATT AT - #T TTT TGG GAA AAC ACT1157Ile Gln Asp Tyr Pro Leu Ile Tyr Glu Ile Il - #e Phe Trp Glu Asn Thr# 375- TCA AAT GCT GAG AGA AAA ATT ATC GAG AAA AA - #A ACT GAT GTT ACA GTT1205Ser Asn Ala Glu Arg Lys Ile Ile Glu Lys Ly - #s Thr Asp Val Thr Val# 390- CCT AAT TTG AAA CCA CTG ACT GTA TAT TGT GT - #G AAA GCC AGA GCA CAC1253Pro Asn Leu Lys Pro Leu Thr Val Tyr Cys Va - #l Lys Ala Arg Ala His# 405- ACC ATG GAT GAA AAG CTG AAT AAA AGC AGT GT - #T TTT AGT GAC GCT GTA1301Thr Met Asp Glu Lys Leu Asn Lys Ser Ser Va - #l Phe Ser Asp Ala Val410 4 - #15 4 - #20 4 -#25- TGT GAG AAA ACA AAA CCA GGA AAT ACC TCT AA - #A TGAGGTACC#1343Cys Glu Lys Thr Lys Pro Gly Asn Thr Ser Ly - #s# 435- (2) INFORMATION FOR SEQ ID NO: 2:- (i) SEQUENCE CHARACTERISTICS:#acids (A) LENGTH: 436 amino (B) TYPE: amino acid (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: protein#2: (xi) SEQUENCE DESCRIPTION: SEQ ID NO:- Met Met Val Val Leu Leu Gly Ala Thr Thr Le - #u Val Leu Val Ala Val# 15- Gly Pro Trp Val Leu Ser Ala Ala Ala Gly Gl - #y Lys Asn Leu Lys Ser# 30- Pro Gln Lys Val Glu Val Asp Ile Ile Asp As - #p Asn Phe Ile Leu Arg# 45- Trp Asn Arg Ser Asp Glu Ser Val Gly Asn Va - #l Thr Phe Ser Phe Asp# 60- Tyr Gln Lys Thr Gly Met Asp Asn Trp Ile Ly - #s Leu Ser Gly Cys Gln# 80- Asn Ile Thr Ser Thr Lys Cys Asn Phe Ser Se - #r Leu Lys Leu Asn Val# 95- Tyr Glu Glu Ile Lys Leu Arg Ile Arg Ala Gl - #u Lys Glu Asn Thr Ser# 110- Ser Trp Tyr Glu Val Asp Ser Phe Thr Pro Ph - #e Arg Lys Ala Gln Ile# 125- Gly Pro Pro Glu Val His Leu Glu Ala Glu As - #p Lys Ala Ile Val Ile# 140- His Ile Ser Pro Gly Thr Lys Asp Ser Val Me - #t Trp Ala Leu Asp Gly145 1 - #50 1 - #55 1 -#60- Leu Ser Phe Thr Tyr Ser Leu Leu Ile Trp Ly - #s Asn Ser Ser Gly Val# 175- Glu Glu Arg Ile Glu Asn Ile Tyr Ser Arg Hi - #s Lys Ile Tyr Lys Leu# 190- Ser Pro Glu Thr Thr Tyr Cys Leu Lys Val Ly - #s Ala Ala Leu Leu Thr# 205- Ser Trp Lys Ile Gly Val Tyr Ser Pro Val Hi - #s Cys Ile Lys Thr Thr# 220- Val Glu Asn Glu Leu Pro Pro Pro Glu Asn Il - #e Glu Val Ser Val Gln225 2 - #30 2 - #35 2 -#40- Asn Gln Asn Tyr Val Leu Lys Trp Asp Tyr Th - #r Tyr Ala Asn Met Thr# 255- Phe Gln Val Gln Trp Leu His Ala Phe Leu Ly - #s Arg Asn Pro Gly Asn# 270- His Leu Tyr Lys Trp Lys Gln Ile Pro Asp Cy - #s Glu Asn Val Lys Thr# 285- Thr Gln Cys Val Phe Pro Gln Asn Val Phe Gl - #n Lys Gly Ile Tyr Leu# 300- Leu Arg Val Gln Ala Ser Asp Gly Asn Asn Th - #r Ser Phe Trp Ser Glu305 3 - #10 3 - #15 3 -#20- Glu Ile Lys Phe Asp Thr Glu Ile Gln Ala Ph - #e Leu Leu Pro Pro Val# 335- Phe Asn Ile Arg Ser Leu Ser Asp Ser Phe Hi - #s Ile Tyr Ile Gly Ala# 350- Pro Lys Gln Ser Gly Asn Thr Pro Val Ile Gl - #n Asp Tyr Pro Leu Ile# 365- Tyr Glu Ile Ile Phe Trp Glu Asn Thr Ser As - #n Ala Glu Arg Lys Ile# 380- Ile Glu Lys Lys Thr Asp Val Thr Val Pro As - #n Leu Lys Pro Leu Thr385 3 - #90 3 - #95 4 -#00- Val Tyr Cys Val Lys Ala Arg Ala His Thr Me - #t Asp Glu Lys Leu Asn# 415- Lys Ser Ser Val Phe Ser Asp Ala Val Cys Gl - #u Lys Thr Lys Pro Gly# 430- Asn Thr Ser Lys 435- (2) INFORMATION FOR SEQ ID NO: 3:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 1755 base (B) TYPE: nucleic acid (C) STRANDEDNESS: double (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: DNA (genomic)- (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 27..1697#3: (xi) SEQUENCE DESCRIPTION: SEQ ID NO:#CTG GGC GCG ACG 53TCCCAG ATG ATG GTC GTC CTC#Leu Leu Gly Ala ThrVal Val# 5 1- ACC CTA GTG CTC GTC GCC GTG GGC CCA TGG GT - #G TTG TCC GCA GCC GCA 101Thr Leu Val Leu Val Ala Val Gly Pro Trp Va - #l Leu Ser Ala Ala Ala# 25- GGT GGA AAA AAT CTA AAA TCT CCT CAA AAA GT - #A GAG GTC GAC ATC ATA 149Gly Gly Lys Asn Leu Lys Ser Pro Gln Lys Va - #l Glu Val Asp Ile Ile# 40- GAT GAC AAC TTT ATC CTG AGG TGG AAC AGG AG - #C GAT GAG TCT GTC GGG 197Asp Asp Asn Phe Ile Leu Arg Trp Asn Arg Se - #r Asp Glu Ser Val Gly# 55- AAT GTG ACT TTT TCA TTC GAT TAT CAA AAA AC - #T GGG ATG GAT AAT TGG 245Asn Val Thr Phe Ser Phe Asp Tyr Gln Lys Th - #r Gly Met Asp Asn Trp# 70- ATA AAA TTG TCT GGG TGT CAG AAT ATT ACT AG - #T ACC AAA TGC AAC TTT 293Ile Lys Leu Ser Gly Cys Gln Asn Ile Thr Se - #r Thr Lys Cys Asn Phe# 85- TCT TCA CTC AAG CTG AAT GTT TAT GAA GAA AT - #T AAA TTG CGT ATA AGA 341Ser Ser Leu Lys Leu Asn Val Tyr Glu Glu Il - #e Lys Leu Arg Ile Arg#105- GCA GAA AAA GAA AAC ACT TCT TCA TGG TAT GA - #G GTT GAC TCA TTT ACA 389Ala Glu Lys Glu Asn Thr Ser Ser Trp Tyr Gl - #u Val Asp Ser Phe Thr# 120- CCA TTT CGC AAA GCT CAG ATT GGT CCT CCA GA - #A GTA CAT TTA GAA GCT 437Pro Phe Arg Lys Ala Gln Ile Gly Pro Pro Gl - #u Val His Leu Glu Ala# 135- GAA GAT AAG GCA ATA GTG ATA CAC ATC TCT CC - #T GGA ACA AAA GAT AGT 485Glu Asp Lys Ala Ile Val Ile His Ile Ser Pr - #o Gly Thr Lys Asp Ser# 150- GTT ATG TGG GCT TTG GAT GGT TTA AGC TTT AC - #A TAT AGC TTA CTT ATC 533Val Met Trp Ala Leu Asp Gly Leu Ser Phe Th - #r Tyr Ser Leu Leu Ile# 165- TGG AAA AAC TCT TCA GGT GTA GAA GAA AGG AT - #T GAA AAT ATT TAT TCC 581Trp Lys Asn Ser Ser Gly Val Glu Glu Arg Il - #e Glu Asn Ile Tyr Ser170 1 - #75 1 - #80 1 -#85- AGA CAT AAA ATT TAT AAA CTC TCA CCA GAG AC - #T ACT TAT TGT CTA AAA 629Arg His Lys Ile Tyr Lys Leu Ser Pro Glu Th - #r Thr Tyr Cys Leu Lys# 200- GTT AAA GCA GCA CTA CTT ACG TCA TGG AAA AT - #T GGT GTC TAT AGT CCA 677Val Lys Ala Ala Leu Leu Thr Ser Trp Lys Il - #e Gly Val Tyr Ser Pro# 215- GTA CAT TGT ATA AAG ACC ACA GTT GAA AAT GA - #A CTA CCT CCA CCA GAA 725Val His Cys Ile Lys Thr Thr Val Glu Asn Gl - #u Leu Pro Pro Pro Glu# 230- AAT ATA GAA GTC AGT GTC CAA AAT CAG AAC TA - #T GTT CTT AAA TGG GAT 773Asn Ile Glu Val Ser Val Gln Asn Gln Asn Ty - #r Val Leu Lys Trp Asp# 245- TAT ACA TAT GCA AAC ATG ACC TTT CAA GTT CA - #G TGG CTC CAC GCC TTT 821Tyr Thr Tyr Ala Asn Met Thr Phe Gln Val Gl - #n Trp Leu His Ala Phe250 2 - #55 2 - #60 2 -#65- TTA AAA AGG AAT CCT GGA AAC CAT TTG TAT AA - #A TGG AAA CAA ATA CCT 869Leu Lys Arg Asn Pro Gly Asn His Leu Tyr Ly - #s Trp Lys Gln Ile Pro# 280- GAC TGT GAA AAT GTC AAA ACT ACC CAG TGT GT - #C TTT CCT CAA AAC GTT 917Asp Cys Glu Asn Val Lys Thr Thr Gln Cys Va - #l Phe Pro Gln Asn Val# 295- TTC CAA AAA GGA ATT TAC CTT CTC CGC GTA CA - #A GCA TCT GAT GGA AAT 965Phe Gln Lys Gly Ile Tyr Leu Leu Arg Val Gl - #n Ala Ser Asp Gly Asn# 310- AAC ACA TCT TTT TGG TCT GAA GAG ATA AAG TT - #T GAT ACT GAA ATA CAA1013Asn Thr Ser Phe Trp Ser Glu Glu Ile Lys Ph - #e Asp Thr Glu Ile Gln# 325- GCT TTC CTA CTT CCT CCA GTC TTT AAC ATT AG - #A TCC CTT AGT GAT TCA1061Ala Phe Leu Leu Pro Pro Val Phe Asn Ile Ar - #g Ser Leu Ser Asp Ser330 3 - #35 3 - #40 3 -#45- TTC CAT ATC TAT ATC GGT GCT CCA AAA CAG TC - #T GGA AAC ACG CCT GTG1109Phe His Ile Tyr Ile Gly Ala Pro Lys Gln Se - #r Gly Asn Thr Pro Val# 360- ATC CAG GAT TAT CCA CTG ATT TAT GAA ATT AT - #T TTT TGG GAA AAC ACT1157Ile Gln Asp Tyr Pro Leu Ile Tyr Glu Ile Il - #e Phe Trp Glu Asn Thr# 375- TCA AAT GCT GAG AGA AAA ATT ATC GAG AAA AA - #A ACT GAT GTT ACA GTT1205Ser Asn Ala Glu Arg Lys Ile Ile Glu Lys Ly - #s Thr Asp Val Thr Val# 390- CCT AAT TTG AAA CCA CTG ACT GTA TAT TGT GT - #G AAA GCC AGA GCA CAC1253Pro Asn Leu Lys Pro Leu Thr Val Tyr Cys Va - #l Lys Ala Arg Ala His# 405- ACC ATG GAT GAA AAG CTG AAT AAA AGC AGT GT - #T TTT AGT GAC GCT GTA1301Thr Met Asp Glu Lys Leu Asn Lys Ser Ser Va - #l Phe Ser Asp Ala Val410 4 - #15 4 - #20 4 -#25- TGT GAG AAA ACA AAA CCA GGA AAT ACC TCT AA - #A ATT TGG CTT ATA GTT1349Cys Glu Lys Thr Lys Pro Gly Asn Thr Ser Ly - #s Ile Trp Leu Ile Val# 440- GGA ATT TGT ATT GCA TTA TTT GCT CTC CCG TT - #T GTC ATT TAT GCT GCG1397Gly Ile Cys Ile Ala Leu Phe Ala Leu Pro Ph - #e Val Ile Tyr Ala Ala# 455- AAA GTC TTC TTG AGA TGC ATC AAT TAT GTC TT - #C TTT CCA TCA CTT AAA1445Lys Val Phe Leu Arg Cys Ile Asn Tyr Val Ph - #e Phe Pro Ser Leu Lys# 470- CCT TCT TCC AGT ATA GAT GAG TAT TTC TCT GA - #A CAG CCA TTG AAG AAT1493Pro Ser Ser Ser Ile Asp Glu Tyr Phe Ser Gl - #u Gln Pro Leu Lys Asn# 485- CTT CTG CTT TCA ACT TCT GAG GAA CAA ATC GA - #A AAA TGT TTC ATA ATT1541Leu Leu Leu Ser Thr Ser Glu Glu Gln Ile Gl - #u Lys Cys Phe Ile Ile490 4 - #95 5 - #00 5 -#05- GAA AAT ATA AGC ACA ATT GCT ACA GTA GAA GA - #A ACT AAT CAA ACT GAT1589Glu Asn Ile Ser Thr Ile Ala Thr Val Glu Gl - #u Thr Asn Gln Thr Asp# 520- GAA GAT CAT AAA AAA TAC AGT TCC CAA ACT AG - #C CAA GAT TCA GGA AAT1637Glu Asp His Lys Lys Tyr Ser Ser Gln Thr Se - #r Gln Asp Ser Gly Asn# 535- TAT TCT AAT GAA GAT GAA AGC GAA AGT AAA AC - #A AGT GAA GAA CTA CAG1685Tyr Ser Asn Glu Asp Glu Ser Glu Ser Lys Th - #r Ser Glu Glu Leu Gln# 550- CAG GAC TTT GTA TGACCAGAAA TGAACTGTGT CAAGTATAAG GT - #TTTTCAGC1737Gln Asp Phe Val 555#1755 CC- (2) INFORMATION FOR SEQ ID NO: 4:- (i) SEQUENCE CHARACTERISTICS:#acids (A) LENGTH: 557 amino (B) TYPE: amino acid (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: protein#4: (xi) SEQUENCE DESCRIPTION: SEQ ID NO:- Met Met Val Val Leu Leu Gly Ala Thr Thr Le - #u Val Leu Val Ala Val# 15- Gly Pro Trp Val Leu Ser Ala Ala Ala Gly Gl - #y Lys Asn Leu Lys Ser# 30- Pro Gln Lys Val Glu Val Asp Ile Ile Asp As - #p Asn Phe Ile Leu Arg# 45- Trp Asn Arg Ser Asp Glu Ser Val Gly Asn Va - #l Thr Phe Ser Phe Asp# 60- Tyr Gln Lys Thr Gly Met Asp Asn Trp Ile Ly - #s Leu Ser Gly Cys Gln# 80- Asn Ile Thr Ser Thr Lys Cys Asn Phe Ser Se - #r Leu Lys Leu Asn Val# 95- Tyr Glu Glu Ile Lys Leu Arg Ile Arg Ala Gl - #u Lys Glu Asn Thr Ser# 110- Ser Trp Tyr Glu Val Asp Ser Phe Thr Pro Ph - #e Arg Lys Ala Gln Ile# 125- Gly Pro Pro Glu Val His Leu Glu Ala Glu As - #p Lys Ala Ile Val Ile# 140- His Ile Ser Pro Gly Thr Lys Asp Ser Val Me - #t Trp Ala Leu Asp Gly145 1 - #50 1 - #55 1 -#60- Leu Ser Phe Thr Tyr Ser Leu Leu Ile Trp Ly - #s Asn Ser Ser Gly Val# 175- Glu Glu Arg Ile Glu Asn Ile Tyr Ser Arg Hi - #s Lys Ile Tyr Lys Leu# 190- Ser Pro Glu Thr Thr Tyr Cys Leu Lys Val Ly - #s Ala Ala Leu Leu Thr# 205- Ser Trp Lys Ile Gly Val Tyr Ser Pro Val Hi - #s Cys Ile Lys Thr Thr# 220- Val Glu Asn Glu Leu Pro Pro Pro Glu Asn Il - #e Glu Val Ser Val Gln225 2 - #30 2 - #35 2 -#40- Asn Gln Asn Tyr Val Leu Lys Trp Asp Tyr Th - #r Tyr Ala Asn Met Thr# 255- Phe Gln Val Gln Trp Leu His Ala Phe Leu Ly - #s Arg Asn Pro Gly Asn# 270- His Leu Tyr Lys Trp Lys Gln Ile Pro Asp Cy - #s Glu Asn Val Lys Thr# 285- Thr Gln Cys Val Phe Pro Gln Asn Val Phe Gl - #n Lys Gly Ile Tyr Leu# 300- Leu Arg Val Gln Ala Ser Asp Gly Asn Asn Th - #r Ser Phe Trp Ser Glu305 3 - #10 3 - #15 3 -#20- Glu Ile Lys Phe Asp Thr Glu Ile Gln Ala Ph - #e Leu Leu Pro Pro Val# 335- Phe Asn Ile Arg Ser Leu Ser Asp Ser Phe Hi - #s Ile Tyr Ile Gly Ala# 350- Pro Lys Gln Ser Gly Asn Thr Pro Val Ile Gl - #n Asp Tyr Pro Leu Ile# 365- Tyr Glu Ile Ile Phe Trp Glu Asn Thr Ser As - #n Ala Glu Arg Lys Ile# 380- Ile Glu Lys Lys Thr Asp Val Thr Val Pro As - #n Leu Lys Pro Leu Thr385 3 - #90 3 - #95 4 -#00- Val Tyr Cys Val Lys Ala Arg Ala His Thr Me - #t Asp Glu Lys Leu Asn# 415- Lys Ser Ser Val Phe Ser Asp Ala Val Cys Gl - #u Lys Thr Lys Pro Gly# 430- Asn Thr Ser Lys Ile Trp Leu Ile Val Gly Il - #e Cys Ile Ala Leu Phe# 445- Ala Leu Pro Phe Val Ile Tyr Ala Ala Lys Va - #l Phe Leu Arg Cys Ile# 460- Asn Tyr Val Phe Phe Pro Ser Leu Lys Pro Se - #r Ser Ser Ile Asp Glu465 4 - #70 4 - #75 4 -#80- Tyr Phe Ser Glu Gln Pro Leu Lys Asn Leu Le - #u Leu Ser Thr Ser Glu# 495- Glu Gln Ile Glu Lys Cys Phe Ile Ile Glu As - #n Ile Ser Thr Ile Ala# 510- Thr Val Glu Glu Thr Asn Gln Thr Asp Glu As - #p His Lys Lys Tyr Ser# 525- Ser Gln Thr Ser Gln Asp Ser Gly Asn Tyr Se - #r Asn Glu Asp Glu Ser# 540- Glu Ser Lys Thr Ser Glu Glu Leu Gln Gln As - #p Phe Val545 5 - #50 5 - #55__________________________________________________________________________

Claims

1. A monoclonal antibody directed against the human interferon type I receptor (IFN-R) characterized by the following properties:

it recognizes an epitope on the amino acid sequence 27-427 of SEQ ID NOS: 1 or 2 or of the human INF-R, and,

it has a neutralizing capacity in vitro against the antiproliferative or antiviral activity of human type I-IFN.

2. The monoclonal antibody directed against the human type I IFN-R according to claim 1, characterized by its capacity to inhibit the binding of a human pathological type I-IFN, to the IFN-R.

3. The monoclonal antibody according to claim 1, which is obtainable from a hybridoma cell prepared by fusion of a myeloma cell with spleen cells from an animal previously immunized with the soluble form of the human IFN-R.

4. The monoclonal antibody according to claim 1, characterized in that it recognizes an epitope on a soluble form of the human cellular IFN-R or of a recombinant IFN-R.

5. The monoclonal antibody according to claim 1, characterized in that it inhibits in vitro the binding of human type I-IFN, to the human cellular IFN-R when it is co-incubated with cells harboring the hu-IFN-R, at a concentration of said antibody equal or inferior to 100 .mu.g/ml.

6. The monoclonal antibody according to claim 1, characterized in that it neutralizes in vitro the antiproliferative activity of the human type I-IFN on Daudi cells at a concentration in a range of 1 to 10 .mu.g/ml.

7. The monoclonal antibody according to claim 1, characterized in that it neutralizes in vitro the antiproliferative activity of the human type I-IFN on LY28 cells at a concentration in a range of 50 to 100 .mu.g/ml.

8. The monoclonal antibody according to claim 1, characterized in that it does not bind to the human receptor of the IFN gamma.

9. Monoclonal antibody according to claim 1, wherein said monoclonal antibody neutralizes in vitro the antiviral activity of the human type I-IFN on Daudi cells at a concentration in a range of 1 to 50 .mu.g/ml for a concentration of type I-IFN in the range of 1 to 1000 units with reference to the international standard MRC69/19.

10. A monoclonal antibody directed against the human interferon type 1 receptor (IFN-R) wherein said monoclonal antibody recognizes the extracellular domain of the human IFN-R of SEQ ID NO: 2 and has a neutralizing capacity in vitro against the biological properties of the human type I-IFN, and wherein said monoclonal antibody is the 64G12 antibody deposited at the ECACC on Feb. 26, 1992 under No. 92022605.

11. A monoclonal antibody, wherein said antibody is a humanized antibody comprising either:

i) the variable regions of the heavy and light chains of the monoclonal antibody according to claim 1 which are grafted on the constant regions of a human antibody, or

ii) the complementarity determining regions of the heavy and light chains of the monoclonal antibody of claim 1 which are grafted on the framework of a human antibody.

12. A monoclonal antibody directed against the human interferon class I receptor (IFN-R) wherein said monoclonal antibody recognizes the extracellular domain of the human IFN-R and has a neutralizing capacity against the biological properties of the human type I-IFN, and wherein said monoclonal antibody is the 64G12 antibody deposited at the ECACC on Feb. 26, 1992 under No. 92022605.

13. The monoclonal antibody according to claim 1, characterized in that it is an IgG1 type antibody.

14. A hybridoma cell, characterized in that it produces the monoclonal antibody according to claim 1.

15. A composition having antagonist properties to the type I-IFN, characterized in that it comprises the monoclonal antibody according to claim 1.

16. A pharmaceutical composition, characterized in that it comprises the monoclonal antibody according to claim 1, together with an appropriate pharmaceutical vehicle.

17. A humanized antibody that specifically binds to the human interferon type I receptor.

18. A human monoclonal antibody that specifically binds to the extracellular domain of the human interferon type I receptor.

19. The monoclonal antibody according to claim 5, wherein said antibody concentration is equal or inferior to 50 .mu.g/ml.

20. The monoclonal antibody according to claim 5, wherein said antibody concentration is equal or inferior to 20 .mu.g/ml.

21. A monoclonal antibody according to claim 5, wherein said antibody concentration is in the range of about 0.5 to 2 .mu.g/ml.

22. A method of treatment or prophylaxis of allograft rejection or autoimmune disease associated with abnormal production of human interferon type-I, comprising administering to a patient in need thereof an effective therapeutic or prophylactic amount of the monoclonal antibody according to claim 1.