EHV-4 gH or gC glycoprotein polypeptides and methods of use

Abstract

The present invention involves isolated equine herpesvirus-4 (EHV-4) or gH or gC polypeptides and antigenic fragments. Methods of using the polypeptides and the fragments thereof are also presented.

Description

FIELD OF THE INVENTION

The present invention is concerned with a nucleic acid sequence encoding an Equine herpesvirus-4 polypeptide, a recombinant nucleic acid molecule comprising such a nucleic acid sequence, a vector virus or host cell containing said nucleic acid sequence, an EHV-4 polypeptide, antibodies immuno-reactive with said polypeptide, a vaccine against EHV-4 infection, as well as methods for the preparation of such a vaccine.

Equine herpesvirus-4 (EHV-4) is, like the related equine herpesvirus-1, an alphaherpesvirus responsible for significant economic losses within the equine industry. EHV-4 is primarily associated with respiratory disease though EHV-4 induced abortions are occasionally reported/

The genome of EHV-4 has been characterized as a double-stranded linear DNA molecule consisting of two covalently linked segments (L, 109 kbp; S, 35 kbp) the latter being flanked by inverted repeats.

The glycoproteins of herpesviruses mediate essential viral functions such as cellular attachment, penetration into cells and pathogenicity. Furthermore, herpesvirus glycoproteins are critical components in the interaction of the virus with the host immune system.

SUMMARY OF THE INVENTION

A first aspect of the present invention is a nucleic acid sequence encoding EHV-4 gH or gC polypeptide, or an antigenic fragment thereof.

A second aspect of the present invention is a nucleic acid sequence encoding a polypeptide having an amino acid sequence set forth in SEQ ID NO: 2 or SEQ ID NO: 4, or an antigenic fragment thereof.

A further aspect of the present invention is a nucleic acid sequence selected from the group of SEQ ID NO: 1, SEQ ID NO: 3, and fragments of these sequences which encode polypeptides having EHV-gh or EHV-gC antigenicity.

A further aspect of the present invention is an EHV-4 gH or gC polypeptide or an antigenic fragment thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows the BamHI restriction map of the EHV-4 genome (Cullinane A. A. et al., J. Gen. Virol., 69: 1575 (1988).

FIG. 1B shows the sequencing strategy and localization of the EHV-4 gH gene.

FIG. 2A shows the BamHI restriction map of the EHV-4 genome (Cullinane A. A. et al., J. Gen. Virol., 69: 1575 (1988).

FIG. 2B shows the restriction map of Bam HI G indicating sites of cleavage of SalI, EcoRI, BglI and BglII.

FIG. 2C shows the sequencing strategy and limits of open reading frames within the BamHI G fragment.

DETAILED DESCRIPTION OF THE INVENTION

A number of studies, predominantly with the well-characterized glycoproteins of herpes simplex virus (HSV), have demonstrated the importance of herpesvirus glycoproteins in both antibody and cellular immune responses.

Although considerable diversity exists among the herpesvirus glycoproteins in structure and function, some similarities in DNA and protein sequence have been identified. This has lead to the classification of several herpesvirus proteins into different groups, each consisting of homologous proteins being related by the presence of specific conserved regions or sites. Groups of such homologues are for example: Herpes Simplex virus-1 (HSV-1) gB, Pseudorabies virus (PRV) gII, Bovine herpesvirus (BHV) gI: HSV-1, gD, PRV gp50, BHV gIV; EHV-1 gp14, PRV gI, Varicella-zoster virus (VZV) gII. The gH proteins of Herpes simplex virus type 1, Varicella-zoster virus and Pseudorabies virus (PRV) have been mapped and sequenced and showned to be involved in protection against the virus (Gompels, U and A. Minson (1986), Virology 153, 230; Keller, P. M. et al. (1987), Virology 157, 526: patent application Ser. No. WO 89/10965). gC-type glycoproteins sequences of several herpesviruses have been published, e.g. HSV-1, PRV, EHV-1, Frink, R. J., et al. (1983), J. Virol. 45, 634; Robbins, A. K. et al. (1986), J. Virol. 58, 339; Allen, G. P. and Coogle, L. D. (1988), J. Virol. 62, 2850).

However, none of these documents disclose the characterization or exact localisation of the EHV-4 gH or gC homologue on the EHV-4 genome nor do they disclose or teach the use of said proteins or genes encoding said proteins for the preparations of a vaccine to prevent EHV-4 infection.

Herein, the EHV-4 gH-type protein and gC-type protein are termed EHV-4 gH and EHV-4 gC, respectively.

Control by vaccination of EHV-4 infection has been a long-sought goal.

Current vaccines comprise chemically inactivated virus vaccines and modified live-virus vaccines.

However, inactivated vaccines generally induce only a low level of immunity, requiring additional immunizations, disadvantageously require adjuvants and are expensive to product. Further, some infectious virus particles may survive the inactivation process and causes disease after administration to the animal.

In general, attenuated live virus vaccines are preferred because they evoke a more long-lasting immune response (often both humoral and cellular) and are easier to produce.

Up to now, only live attenuated EHV-4 vaccines are available which are based on live EHV-4 virus attenuated by serial passages of virulent strains in tissue culture. However, because of this treatment uncontrolled mutations are introduced into the viral genome, resulting in a population of virus particles heterogeneous in their virulence and immunizing properties

In addition it is well known that such traditional attenuated live virus vaccines can revert to virulence resulting in disease of the inoculated animals and the possible spread of the pathogen to other animals.

Vaccines containing only the necessary and relevant EHV-4 immunogenic material which is capable of eliciting an immune response against the pathogen, or genetic information encoding said material, do not display above-mentioned disadvantages of the live or inactivated vaccines.

According to the present invention a nucleic acid sequence encoding EHV-4 gH or gC polypeptide, or an antigenic fragment thereof can be applied for the preparation of a vaccine for the immunization of horses against EHV-4 infection which does not display above-mentioned drawbacks of inactivated or live attenuated vaccines.

"Nucleic acid sequence" as used herein refers to a polymeric form of nucleotides of any length, both to ribonucleic acid sequences and to deoxy-ribonucleic acid sequences. In principle, this term refers to the primary structure of the molecule. Thus, this term includes double and single stranded DNA, as well as double and single stranded RNA, and modifications thereof.

In general, the term "polypeptide" refers to a molecular chain of amino acid with a biological activity, does not refer to a specific length of the product and if required can be modified in vivo or in vitro, for example by glycosylation, amidation, carboxylation or phosphorylation, thus inter alia peptides, oligopeptides and proteins are included.

Said gH or gC polypeptide are homologous with their gH or gC counter-parts of other herpesviruses and can be identified and characterized by the conserved regions and sites within the gH or gC polypeptide homologues.

The gene encoding EHV-4 gH polypeptide maps to the BamHI C fragment (FIG. 1) and encodes a protein of 855 amino acids in length with a predicted molecular weight of 94.100 D. From the amino acid sequence (SEQ ID NO: 2; the following structural features characteristic of membrane glycoproteins can be derived:

A signal peptide within the extreme N-terminal region of the primary translation product comprising a stretch of hydrophobic amino acid residues is identified. The cleavage site is at about Ala.sub.19, the predicted molecular weight of gH after cleavage of the signal peptide being about 92.130 D. Residues 20-816 constitute the hydrophilic external domain which possesses 11 N-linked glycosylation sites (N-X-S/T). The hydrophobic transmembrane domain of about 20 amino acid residues is located towards the C terminus at about position 837-855. The cytoplasmic domain of EHV-4 gH stretches from about amino acid position 837-855.

A comparison of the amino sequence of the gH proteins of alpha, beta and gamma herpesviruses by Gompels et al. (J. Gen. Virol. 69, 2819, 1988) and Cranage et al. (J. Virol. 62, 1416, 1988) highlighted several features of the gH protein conserved throughout the herpesvirus family

an unusually short cytoplasmic domain of 14 or 15 amino acids in alphaherpesviruses and of 7 or 8 amino acids in beta and gammaherpesviruses four conserved cysteine residues at similar positions relative to the putative transmembrane domain and within conserved local sequence, and a conserved glycosylaticn site sequence NGTV 13-18 amino acids N-terminal to the transmembrane domain. EHV-4 gH exhibits all above features: the proposed cytoplasmic domain is under 20 amino acids in length, the four conserved cysteines are present at positions 556, 591, 663 and 716, and the C-terminal glycosylation site is located within the sequence NGTV (amino acids 796-799) which is positioned 19 amino acids N-terminal to the putative EHV-4 transmembrane domain. The Cys residues at 737 and 740 in the EHV-4 gH occur at sites of cysteine conservation throughout most herpesvirus gHs, with the exception of HSV-1. The strong conservation of cysteine residues between the EHV-4 and HSV-1 gHs and, indeed, throughout the alpha, beta and gammaherpesvirus gHs investigated implies some degree of conservation of the secondary and tertiary structure of these proteins presumably involving disulphide bonding (Gompels et al., 1988, ibid).

The gene encoding the EHV-4 gC polypeptide maps to the BamHI G fragment (FIG. 2) and encodes a protein of 485 amino acids in length with a molecular weight of about 52.500 D. From the amino acid sequence (SEQ ID NO: 4) the following structural features characteristic of membrane glycoproteins can be derived:

The signal peptide is identified at the N-terminus spanning about 32 amino acids with cleavage occuring between the Ala and Ser residues at positions 32 and 33 respectively The external domain of EHV-4 gC spans about residues 33 to 444 and possesses 11 N-linked glycosylation sites (N-X-S/T).

An antigenic determinant of EHV-4 gC is located at about residue 409 (Asn) (Hopp and Woods (1981), PNAS 78, 3824).

Amino acids 445-468 constitute the glycoprotein transmembrane domain. The C-terminal cytoplasmic domain spans residues 469 to 485, is hydrophilic and possesses a net positive charge of 2. gC homologues comprise inter alia conserved amino acids in the C-terminal half positioned around six sites of cysteine conservation. A few of the N-linked glycosylation sites exist in similar positions but are not strictly conserved. A further common feature of gCs is that the C-terminal cytoplasmic domain is short and positively charged (Fitzpatrick, D. R. et al. (1989), Virology 173 , 46; Allen, G. P. and Coogle, L., D., ibid).

For the purpose of comparing the EHV-4 gC to other gCs in terms of the specifically conserved features an alignment of EHV-4 gC, BHV-1 gIII, PRV, gIII, HSV-1 gC, and MDV A antigen is carried out. EHV-4 gC possesses cysteine residues at each of the six conserved positions, amino acids 256, 318, 357, 361, 390 and 416. Nine putative EHV-4 gC glycosylation sites are conserved in EHV-1 gp13 and three in PRV gIll.

Also included within the present invention are nucleic acid sequences encoding an antigenic fragment of the EHV-4 gH or gC polypeptide, i.e. a fragment of said gH or gC polypeptide comprising a molecular configuration capable of eliciting any type of immune response, humoral and/or cellular, against said gH or gC polypeptide in a susceptible animal, when presented in a suitable form. Furthermore, said fragment is characteristic for an EHV-4 gH or gC polypeptide.

Particularly, a nucleic acid sequence according to the invention can be used that encodes an EHV-4 polypeptide having an amino acid sequence depicted in SEQ ID NO: 2 or SEQ ID NO: 4, or a derivative of said polypeptide.

The gene encoding the EHV-4 gH and gc polypeptide haven been localized on the EHV-4 genome and the nucleotide sequences thereof are depicted in SEQ ID NO: 1 and SEQ ID NO: 3, respectively. This information can be used to genetically manipulate said genes or derivatives thereof, for example to clone the genes by recombinant DNA techniques generally known in the art and to express the polypeptides encoded thereby in vitro or in viva. Nucleic acid sequences having above-mentioned nucleotide sequences or derivatives thereof are preferably used for the expression of the EHV-4 gH or gC polypeptides.

It will be understood that for the particular EHV-4 gH or gC polypeptide embraced herein, natural variations can exist between individual EHV-4 viruses or strains. These variations may be demonstrated by (an) amino acid difference(s) in the overall sequence or by deletions, substitutions, insertions, inversions or additions of (an) amino acid(s) in said sequence. All such derivatives are included within the scope of this invention. Moreover, the potential exist to use recombinant DNA technology for the preparation of nucleic acid sequences encoding these various derivatives.

As is well known in the art, the degeneracy of the genetic code permits substitution of bases in a codon resulting in an other codon but still coding for the same amino acid, e.g. the codon for the amino acid glutamic acid is both GAT and GAA. Consequently, it is clear that for the expression of a polypeptide with the amino acid sequence shown in SEQ ID NO: 2 or SEQ ID NO: 4, or an antigenic fragment thereof use can be made of a derivate nucleic acid sequence with such an alternative codon composition different from the nucleic acid sequence shown in SEQ ID NO: 1 and SEQ ID NO: 3.

Furthermore, also fragments derived from the EHV-4 gH or gc polypeptide or from the amino acid sequences depicted in SEQ ID NO: 2 or SEQ ID NO: 4 which still display EHV-4 gH or gC antigenic properties, or fragments derived from the nucleotide sequences encoding the EHV-4 gH or gC polypeptide or derived from the nucleotide sequences depicted in said SEQ ID NO: 1 and SEQ ID NO: 3 encoding antigenic fragments of said gH or gc polypeptides are also included in the present invention.

All such modifications mentioned above resulting in such derivatives of the EHV-4 gH or gC polypeptide or gene are covered by the present invention so long as the characteristic EHV-4 gH or gC features remain unaffected in essence.

A nucleic acid sequence according to the present invention can be ligated to various expression effecting DNA sequences, optionally containing portions of DNA encoding fusion protein sequences such as .beta.-galactosidase, resulting in a so called recombinant nucleic acid molecule which can be used for the transformation of a suitable host. Such hybrid DNA molecules, are preferably derived from, for example plasmids, or from nucleic acid sequences present in bacteriophages or viruses.

Specific vectors which can be used to clone nucleic acid sequences according to the invention are known in the art (e.g. Rodriguez, R. L. and D. T. Denhardt, edit., Vectors: A survey of molecular cloning vectors and their uses, Butterworths, 1988).

The methods to be used for the construction of a recombinant nucleic acid molecule according to the invention are know to those of ordinary skill in the art and are inter alia set forth in Maniatis, T. et al. (Molecular Cloning: A Laboratory Manual, Cold Spring Harbor Laboratory, 1982).

"Transformation", as used herein, refers to the introduction of a heterologous nucleic acid sequence into a host cell, irrespective of the method used, for example direct uptake or transduction. The heterologous nucleic acid sequence may be maintained through autonomous replication or alternatively, may be integrated into the host genome. The recombinant DNA molecules preferably are provided with appropriate control sequences compatible with the designated host which can regulate the expression of the inserted nucleic acid sequence.

A suitable host cell is a cell which can be transformed by a nucleic acid sequence encoding a polypeptide or by a recombinant nucleic acid molecule comprising such a nucleic acid sequence and which can be used to express said polypeptide coded by said nucleic acid sequence. The host cell can be of procaryotic origin, e.g. bacteria such as E. coli, B. subtilis and Pseudomonas species; or of eucaryotic origin such as yeasts, e.g Saccharomyces cerevisiae or higher eucaryotic cells such as insect, plant or mammalian cells, including HeLa cells and Chinese hamster ovary (CHO) cells. Insect cells include the Sf9 cell line of Spodoptera frugiperda. Information with respect to the cloning and expression of the nucleic acid sequences of the present invention in eucaryotic cloning systems can be found in Esser, K. et al. (Plasmids of Eukaryotes, Springer-Verlag, 1986).

The nucleic acid sequences of the present invention are preferably operably linked to expression control sequences.

Such control sequences may comprise promoters, operators, inducers, ribosome binding sites etc.

When the host cells are bacteria, illustrative useful expression control sequences include the trp promoter and operator (Goeddel, et al., Nucl. Acids Res. 8, 4057, 1980); the lac promoter and operator (Chang, et al., Nature 275, 615, 1978); the outer membrane protein promoter (EMBO J. 1, 771-775, 1982); the bacteriophage .lambda. promoters and operators (Nucl. Acids Res. 11, 4677-4688, 1983); the .alpha.-amylase (B. subtilis) promoter and operator, termination sequences and other expression enhancement and control sequences compatible with the selected host cell. When the host cell is yeast, illustrative useful expression control sequences include, e.g., .alpha.-mating factor. For insect cells the polyhedrin promoter of baculoviruses can be used (Mol. Cell. Biol. 3, 2156-65, 1983). When the host cell is of insect or mammalian origin illustrative useful expression control sequences include, e.g., the SV-40 promoter (Science 222, 524-527, 1983) or, e.g., the metallothionein promoter (Nature 296, 39-42, 1982) or a heat shock promoter (Voellmy et al., Proc. Natl. Acad. Sci. USA 82, 4949-53, 1985). Alternatively, also expression control sequence present in EHV-4, in particular those regulating the expression of gH or gC may be applied.

The present invention also comprises an EHV-4 gH or gC polypeptide or an antigenic fragment thereof, essentially free from the whole virus or other protein with which it is ordinarily associated.

In particular, a polypeptide comprising at least part of the amino acid sequence depicted in SEQ ID NO: 2 or SEQ ID NO: 4 or derivatives thereof is included in the present invention.

In an other embodiment of the invention a polypeptide having an amino acid sequence encoded by a nucleic acid sequence mentioned above is used.

Immunization of horses against EHV-4 infection can, for example be achieved by administering to the horse a polypeptide according to the invention as a so-called subunit vaccine. The subunit vaccine according to the invention may comprise a polypeptide in a pure form, optionally in the presence of a pharmaceutically acceptable carrier. The polypeptide can optionally be covalently bonded to a non-related protein, which, for example can be of advantage in the purification of the fusion product. Examples are .beta.-galactosidase, protein A, prochymosine, blood clotting factor Xa, etc.

In some cases the ability to raise neutralizing antibodies against these polypeptides per se may be low. Small fragments are preferably conjugated to carrier molecules in order to raise their immunogenicity. Suitable carriers for this purpose are macromolecules, such as natural polymers (proteins, like key hole limpet hemocyanin, albumin, toxins), synthetic polymers like polyamino acids (polylysine, polyalanine), or micelles of amphiphilic compounds like saponins. Alternatively these fragments may be provided as polymers thereof, preferably linear polymers.

Polypeptides to be used in such subunit vaccines can be prepared by methods known in the art, e.g. by isolation said polypeptides from EHV-4, by recombinant DNA techniques or by chemical synthesis.

If required the polypeptides according to the invention to be used in a vaccine can be modified in vitro or in vivo, for example by glycosylation, amidation, carboxylation or phosphorylation.

An alternative to subunit vaccines are live vector vaccines. A nucleic acid sequence according to the invention is introduced by recombinant DNA techniques into a micro-organism (e.g. a bacterium or virus) in such a way that the recombinant microorganism is still able to replicate thereby expressing a polypeptide coded by the inserted nucleic acid sequence. Next, this recombinant micro-organism can be administered to the horse for immunization whereafter it maintains itself for some time, or even replicates, in the body of the inoculated horse, expressing in vivo a polypeptide coded for by the inserted nucleic acid sequence according to the invention resulting in the stimulation of the immune system of the inoculated horse. Suitable vectors for the incorporation of a nucleic acid sequence according to the invention are derived from, for example viruses such as EHV-1, adenovirus, vaccinia virus or other pox viruses, papilloma virus or bacteria such as E. coli or specific Salmonella species. With recombinant micro-organisms of this type, the polypeptide synthesized in the host cell can be exposed as a surface antigen. In this context fusion of the said polypeptide with OMP proteins or pilus proteins of Escherichia coli or synthetic provision of signal and anchor sequences which are recognized by the organism are conceivable. It is also possible that the said immunogenic polypeptide, if desired as part of a larger whole, is released inside the animal to be immunized. In all of these cases it is also possible that one or more immunogenic products will find expression which generate protection against various pathogens and/or against various antigens of a given pathogen.

A vaccine according to the invention can be prepared by culturing a host cell comprising a nucleic acid sequence according to the invention, whereafter the cells and/or vector viruses grown in the cells can be collected, optionally in a pure form, and formed to a vaccine optionally in a lyophilized form.

Abovementioned host cells comprising a nucleic acid sequence according to the invention can also be cultured under conditions which are favourable for the expression of a polypeptide coded by said nucleic acid sequence. Vaccines may be prepared using samples of the crude culture, host cell lysates or host cell extracts although in another embodiment more purified polypeptides according to the invention are formed to a vaccine, depending on its intended use. In order to purify the polypeptides produced, host cells containing a nucleic acid sequence according to the invention are cultured in an adequate volume and the polypeptides produced are isolated from such cells or from the medium if the protein is excreted. Polypeptides excreted into the medium can be isolated and purified by standard techniques, e.g. salt fractionation, chromatography, centrifugation, whereas intracellular polypeptides can be isolated by first collecting said cells, lysing the cells followed by separation of the polypeptides from the other intracellular components and forming the polypeptides to a vaccine.

It goes without saying that horses already infected by EHV-4 can be treated with antibodies directed against said EHV-4. Antiserum or antibodies characteristic for a polypeptide according to the invention can be used for the therapeutic treatment of EHV-4 infection. Said characteristic antiserum or antibodies may be obtained by immunizing animals with an effective amount of EHV-4 gH or gC polypeptide in order to elicit an appropriate immune response. Thereafter the animals are bled and antiserum can be prepared.

Monoclonal antibodies directed against a polypeptide according to the invention can also be used for the therapy of horses infected with EHV-4. Said monoclonal antibodies can be produced by methods known in the art for this purpose, e.g. by immunizing mice with said polypeptide, immortalizing mouse spleen cells and selecting hybridomas producing useful antibodies. Immortal antibody-producing cell lines can also be created by direct transformation of B lymphocytes with oncogcenic DNA, or transfection with Epstein-Barr virus.

Monoclonal antibodies, in particular, may be used to raise anti-idiotype antibodies by methods known in the art. These anti-idiotype antibodies may also be useful for prevention of EHV-4 infection in horses.

Abovementioned antiserum and monoclonal antibodies can also be used for the immunological diagnosis of horses infected with EHV-4.

The vaccine according to the invention can be administered in a conventional active immunization scheme: single or repeated administration in a manner compatible with the dosage formulation and in such amount as will be prophylactically and/or therapeutically effective and immunogenic. The administration of the vaccine can be done, e.g. intradermally, subcutaneously, intramusculary, intravenously or intranasally.

Additionally the vaccine may also contain an aqueous medium or a water containing suspension, often mixed with other constituents, e.g. in order to increase the activity and/or shelf life. These constituents may be salts, pH buffers, stabilizers (such as skimmed milk or casein hydrolysate), emulsifiers, adjuvants to improve the immune response (e.g. oils, muramyl dipeptide, aluminium hydroxide, saponin, polyanions and amphipatic substances) and preservatives.

It is clear that a vaccine according to the invention may also contain immunogens related to other pathogens of horses or may contain nucleic acid sequences encoding these immunogens, like antigens of EHV-1, equine influenza virus, -rotavirus, -infectious anemia virus, -arteritis virus, -encephalitis virus, Borna disease virus of horses, Berue virus of horses, E.coii or Streptococcus equi to produce a multivalent vaccine.

EXAMPLE 1

Isolation and Characterization of gH Gene

1. Culturing of EHV-4 virus

Roller bottles of slightly sub-confluent monolayers of equine dermal cells (NBL-6) grown in Earle's Minimum Essential Medium (Flow) supplemented with 0,2% sodium bicarbonate, 1% non-essential amino acids, 1% glutamine, 100 units/ml penicillin, 100 mg/ml streptomycin and 10% foetal calf serum were infected with virus of the EHV-4 strain 1942 at a m.o.i. of 0,003 and allowed to adsorb for 60 min at 37.degree. C. They were incubated at 31.degree. C. until extensive c.p.e. was evident and the majority of cells had detached from the bottle surface (2-6 days). The infected cell medium was centrifuged at 5.000 r.p.m. for 5 min to pellet the cells, and the supernatant was centrifuged at 12.000 r.p.m. for 2 hours in a Sorvall GSA 6.times.200 ml rotor. The pellet was resuspended in 5 ml PBS, sonicated and centrifuged at 11.000 r.p.m. in a Sorvall SS34 rotor for 5 min to spin down cellular debris. Virus was then pelleted by centrifugation at 18.000 r.p.m. in a Sorvall SS34 rotor for 1 hour. Ratios of virus particles to plaque-forming units were approximately 1.000 to 5.000.

2. Preparation of EHV-4 DNA

The pelleted virus was resuspended in 10 ml NTE (NaCl/Tris/EDTA) and briefly sonicated. Contaminating cellular DNA was degraded by adding DNase at 10 .mu.g/ml and incubating at 37.degree. C. for 1 hour. SDS was added to a final concentration of 2%, and the preparation was extracted approximately 3 times with NTE equilibrated phenol until a clear interphase was obtained.

A chloroform extraction was followed by ethanol precipitation of the DNA as described above. The DNA was pelleted, washed with 70% ethanol, resuspended in 10 ml of 100 mM NaCl and 10 .mu.g/ml RNase and left overnight at room temperature. Further purification was achieved by treatment with 1 mg/ml proteinase K for 2 hours at 31.degree. C. The DNA was extracted once with phenol:chloroform (1:1 vol/vol), once with chloroform, ethanol precipitated, drained well and resuspended in 0.1.times. SSC.

3. Cloning of EHV-4 DNA

EHV-4 BamHI DNA fragments were ligated into the vector pUC9, a plasmid which includes the amoicillin-resistance gene from pBR322 and the polylinker region from M13mp9 (Vieira, J. and Messing, J. (1982), Gene 19, 259). 5 .mu.g of EHV-4 DNA and 5 .mu.g pUC9 DNA were separately digested with BamHI.

Complete digestion was verified by gel electrophoresis of aliquots of the reactions and then the DNA was extracted twice with an equal volume of phenol:chloroform (1:1) and ethanol-precipitated. Ligation was performed essentially by the method of Tanaka and Weisblum (J. Bact. 121, 354, 1975). Approximately 0,1 .mu.g of BamHI digested pUC9 and 1 .mu.g of BamHI-digested EHV-4 DNA were mixed in 50 mM Tris-HCl pH 7,5, 8 mM MgCl.sub.2, 10 mM dithiothreitol, 1 mM ATP in a final volume of 40 .mu.l. 2 units of T4 DNA ligase (0,5 .mu.l) were then added. The reaction was incubated at 4.degree. C. for 16 hours.

Calcium-shocked E.coli DHI cells (Hanahan, D. (1983), J.Mol.Biol. 166, 557) were transformed with the recombinant plasmids essentially described by Cohen et al. (Proc.Natl.Acad.Sci., USA 69, 2110, 1972). Additional clones were derived by restriction digestion of recombinant plasmid pUC9 containing BamHI C fragment (FIG. 1), followed by recovering of the specific EHV-4 restriction fragments and sub-cloning thereof (Maniatis, T. et al., ibid) within the multi-cloning site of the Bluescript M13.sup.+ plasmid vector (Stratagene) for sequence analysis.

The nucleotide sequence of a region of BamHI C fragment spanning the gH gene was determined by using single stranded plasmid DNA as template and Bluescript-derived and custom-made oligonucleotides as primers in a Sanger dideoxy sequencing strategy (Sanger et al., Proc. Natl. Acad. Sci. 74, 5463,1977) (FIG. 1). The exact localisation, nucleic acid sequence and corresponding amino acid sequence of the gH gene is shown in the SEQ ID NO: 1.

EXAMPLE 2

Isolation and Characterization of gC Gene

Culturing of EHV-4 virus, preparation of EHV-4 DNA and construction of a BamHI library in pUC9 was carried out as outlined above.

Recombinant plasmid pUC9:EHV-4 BamHI G was restriction enzyme digested to generate subfragments of EHV-4 BamHI G which were then isolated from 0,7% agarose gels and cloned into a Bluescript M13.sup.+ plasmid vector (Stratagene) by standard techniques (Maniatis, T. et al., ibid.). Recombinant plasmids were propagated in E. coli strain JM83 in 1-broth supplemented with ampicillin (100 .mu.g/ml). Plasmid DNA was extracted from 500 ml bacterial cultures by the alkaline lysis method and purified by banding on CsCl gradients.

DNA sequencing was carried out by the Sanger dideoxy technique (Sanger et al., ibid.) using denatured recombinant plasmid DNA as template and M13.sup.+ -specific or custom oligonucleotides as primers. The nucleotide sequence of a region of the BamHI G fragment spanning the gC gene was determined by analysis of overlapping sequences according to the strategy detailed in FIG. 2.

The exact localisation, nucleotide sequence and corresponding amino acid sequence of the gC gene is shown in the SEQ ID NO: 4, respectively.

__________________________________________________________________________# SEQUENCE LISTING- (1) GENERAL INFORMATION:- (iii) NUMBER OF SEQUENCES: 5- (2) INFORMATION FOR SEQ ID NO:1:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 2730 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: DNA (genomic)- (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 65..2629- (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:- CAGCGCGGCC GAGATACTCG AGGTATCCAG TGGTTGTATA TTGGGAATAA AT - #ACTGCTGC 60- GATT ATG TCA CAA CCG TAT CTA AAA ATA GCT A - #TC TTA GTG GCC GCT ACT 109 Met Ser Gln Pro Tyr Leu Lys Ile - # Ala Ile Leu Val Ala Ala Thr# 15- ATT GTG TCT GCG ATT CCC GTT TGG ACA ACA CC - #G GTT TCA ACT TCA CCA 157Ile Val Ser Ala Ile Pro Val Trp Thr Thr Pr - #o Val Ser Thr Ser Pro# 30- CCC CAA CAA ACA AAA TTG CAC TAT GTG GGA AA - #T GGT ACC TGG GTA CAC 205Pro Gln Gln Thr Lys Leu His Tyr Val Gly As - #n Gly Thr Trp Val His# 45- AAC AAT ACA TTC AAC GTA ACC AGG TAT GAC AG - #G ATA ACC ATG GAA CCA 253Asn Asn Thr Phe Asn Val Thr Arg Tyr Asp Ar - #g Ile Thr Met Glu Pro# 60- GTT TAT AAT AAC AAT TTA TCC TCT ACT ACC TT - #T TTT GTT GCT ATA TCG 301Val Tyr Asn Asn Asn Leu Ser Ser Thr Thr Ph - #e Phe Val Ala Ile Ser# 75- GAG AGA AAT TTT CGC ACG GTT AAC ACT CCA CT - #T GGA GCG TCC GTA TTT 349Glu Arg Asn Phe Arg Thr Val Asn Thr Pro Le - #u Gly Ala Ser Val Phe# 95- TGG ATT TTA AAA AGC GCT CTT AAT CCT CCC AA - #A CAC CAA CCC TGT ATA 397Trp Ile Leu Lys Ser Ala Leu Asn Pro Pro Ly - #s His Gln Pro Cys Ile# 110- GCT AAT GTG CCA GAA CCC GGT GAC CCA CGC GG - #A CCG TGC GTC AAC TCA 445Ala Asn Val Pro Glu Pro Gly Asp Pro Arg Gl - #y Pro Cys Val Asn Ser# 125- ACT GTG AGT CTA TTT TTT AAT GAC AAT TTG GA - #G CCG TTT TTA ATG ACA 493Thr Val Ser Leu Phe Phe Asn Asp Asn Leu Gl - #u Pro Phe Leu Met Thr# 140- AAA AAT CTT TTG GAG TTT GAA GTA TTG CCC GA - #C AAC TAC ATA ACC GGA 541Lys Asn Leu Leu Glu Phe Glu Val Leu Pro As - #p Asn Tyr Ile Thr Gly# 155- TGG ACG TTT GAG CGG TCT AAA ACT GTG GCT AC - #G AAA GGC AAC CCG GTT 589Trp Thr Phe Glu Arg Ser Lys Thr Val Ala Th - #r Lys Gly Asn Pro Val160 1 - #65 1 - #70 1 -#75- GGA GTG GTT CTC TCC CCT CCC CGA ACA AGT CC - #G GAT GTA AAT AAC ACC 637Gly Val Val Leu Ser Pro Pro Arg Thr Ser Pr - #o Asp Val Asn Asn Thr# 190- ATA AGA GAT GAT GGC ACC CCT AAA CAG CAC TT - #G AGC ATT ATA GAC GAA 685Ile Arg Asp Asp Gly Thr Pro Lys Gln His Le - #u Ser Ile Ile Asp Glu# 205- CAT ACT ACG TTC GTG CTC GAC CTG CAA AAT TT - #T ACA AAA ACT TTA ACT 733His Thr Thr Phe Val Leu Asp Leu Gln Asn Ph - #e Thr Lys Thr Leu Thr# 220- TAT ATA AGC CCA TTT GCT GCG GTG TGG CCA AT - #A ACA GCC TTT CAT GCC 781Tyr Ile Ser Pro Phe Ala Ala Val Trp Pro Il - #e Thr Ala Phe His Ala# 235- GGA ATT ACA GTA ATG GGG TGT GAC ACA ACT CA - #G GCG ATT GCG TAC CTC 829Gly Ile Thr Val Met Gly Cys Asp Thr Thr Gl - #n Ala Ile Ala Tyr Leu240 2 - #45 2 - #50 2 -#55- GGC AAT GGG TTT ATG GGT TTG CAA ATA AGC TC - #G GTA AAC AAT CCA CCG 877Gly Asn Gly Phe Met Gly Leu Gln Ile Ser Se - #r Val Asn Asn Pro Pro# 270- CTG GAG ATG ATT GTT GCA CCA AAT GAC GTC CG - #T GCT CGG ATA GTT AAC 925Leu Glu Met Ile Val Ala Pro Asn Asp Val Ar - #g Ala Arg Ile Val Asn# 285- CGC CTT CCC CCA AGA CGT CGA CTT GAG CCA CC - #C GGG CCA TAT GCA GGA 973Arg Leu Pro Pro Arg Arg Arg Leu Glu Pro Pr - #o Gly Pro Tyr Ala Gly# 300- CCT ATC TAC AAG GTG TAC GTA CTC AGT GAT GG - #A AAT TTT TAC TTG GGT1021Pro Ile Tyr Lys Val Tyr Val Leu Ser Asp Gl - #y Asn Phe Tyr Leu Gly# 315- CAT GGC ATG AGC AAG ATT TCT AGG GAG GTT GC - #C GCG TAC CCA GAA GAG1069His Gly Met Ser Lys Ile Ser Arg Glu Val Al - #a Ala Tyr Pro Glu Glu320 3 - #25 3 - #30 3 -#35- AGT TTG GAC TAC CGC TAC CAC TTA TCG CTT GC - #C AAC CTT GAT ACT CTG1117Ser Leu Asp Tyr Arg Tyr His Leu Ser Leu Al - #a Asn Leu Asp Thr Leu# 350- GCT ATG TTG GCA GAA CTT TCT TCC GGT AAG AG - #C AAG GAT GTG AGC TAT1165Ala Met Leu Ala Glu Leu Ser Ser Gly Lys Se - #r Lys Asp Val Ser Tyr# 365- TAC TTG TAT CGC ATA ATT GCG AGG CTG GCC GT - #A GCA ACG TTT TCC CTT1213Tyr Leu Tyr Arg Ile Ile Ala Arg Leu Ala Va - #l Ala Thr Phe Ser Leu# 380- GCA GAA GTT ATA CGC CTG AGT GAC TAT ATG CT - #C CTT CAA GAG GCC ATC1261Ala Glu Val Ile Arg Leu Ser Asp Tyr Met Le - #u Leu Gln Glu Ala Ile# 395- GAC GTG GAT ATA AAC CTC CGC CTA ATT GTA CC - #T CTA GTG ATG AAG TAC1309Asp Val Asp Ile Asn Leu Arg Leu Ile Val Pr - #o Leu Val Met Lys Tyr400 4 - #05 4 - #10 4 -#15- GCC GCT GGG GGA ACG GCA GAT AGC TCG TAC AC - #A TCC TCG GAC GTA GCT1357Ala Ala Gly Gly Thr Ala Asp Ser Ser Tyr Th - #r Ser Ser Asp Val Ala# 430- ATG GAC CAA TTC GAG GTG GCT CAA GCC CAG AT - #T GAG AAG ATA GTA GCC1405Met Asp Gln Phe Glu Val Ala Gln Ala Gln Il - #e Glu Lys Ile Val Ala# 445- GAT ATA AAT ATC GAA AAT GAA TTG CGC AAA CC - #T ATG TAC GAG CAC CGC1453Asp Ile Asn Ile Glu Asn Glu Leu Arg Lys Pr - #o Met Tyr Glu His Arg# 460- TCA TTA TTG AAA AGC GTG TAC GCT TAT TCT AG - #A AAG CCG CTA CCA AAC1501Ser Leu Leu Lys Ser Val Tyr Ala Tyr Ser Ar - #g Lys Pro Leu Pro Asn# 475- GCG GTA AGC TTT GCT AAC CGG CTC ATC ACG GC - #T ATG TAT AAA GAA GCA1549Ala Val Ser Phe Ala Asn Arg Leu Ile Thr Al - #a Met Tyr Lys Glu Ala480 4 - #85 4 - #90 4 -#95- ATT AAG GAC AGA ATT ACG TGG AAC TCT ACG AT - #G CGA GAG GTG TTA TTT1597Ile Lys Asp Arg Ile Thr Trp Asn Ser Thr Me - #t Arg Glu Val Leu Phe# 510- TTT GCG GTT GGT GCT GCT GCA GGT TCG CAT GT - #T ATC CTC ACG GAT GGG1645Phe Ala Val Gly Ala Ala Ala Gly Ser His Va - #l Ile Leu Thr Asp Gly# 525- CCA GAT CTC GGT TTA CAT GCC CAC AAA GAT TC - #T TCG ATG TTT CTA TCT1693Pro Asp Leu Gly Leu His Ala His Lys Asp Se - #r Ser Met Phe Leu Ser# 540- CTT AAC CGC AAC ATA CTC TTG TTG TGT ACG GC - #C ATG TGT ACG GCG TCG1741Leu Asn Arg Asn Ile Leu Leu Leu Cys Thr Al - #a Met Cys Thr Ala Ser# 555- CAT GCC GTG TCC GCA GGA GTA AAA CTA GAG GA - #A GTT ATG GCT GGC CTT1789His Ala Val Ser Ala Gly Val Lys Leu Glu Gl - #u Val Met Ala Gly Leu560 5 - #65 5 - #70 5 -#75- ATT GCC GGG GGT GTA CAA TTT AGC CTC CTA GA - #A GTA TTT AGT CCA TGT1837Ile Ala Gly Gly Val Gln Phe Ser Leu Leu Gl - #u Val Phe Ser Pro Cys# 590- ATG GCG TCT GCT CGA TTT GAC CTG GCC GAA GA - #A GAG CAT GTG CTA GAT1885Met Ala Ser Ala Arg Phe Asp Leu Ala Glu Gl - #u Glu His Val Leu Asp# 605- CTA CTG TCC GTT ATC CCA CCT CGC CTG TAC AC - #C GAC TTA AAC ACT GGC1933Leu Leu Ser Val Ile Pro Pro Arg Leu Tyr Th - #r Asp Leu Asn Thr Gly# 620- TTG GAG GAC GAC GGA ACC ACC ATC CAT TCA TA - #C GGA CGG TCT GCT AAC1981Leu Glu Asp Asp Gly Thr Thr Ile His Ser Ty - #r Gly Arg Ser Ala Asn# 635- GGA ATT TTA AAC TCT CGA ATC GCA TAT AAC TT - #T GAT GCT GTT CGT GTA2029Gly Ile Leu Asn Ser Arg Ile Ala Tyr Asn Ph - #e Asp Ala Val Arg Val640 6 - #45 6 - #50 6 -#55- TTT ACT CCA GAG TTG GCC TCA TGC AGC ACT AA - #A CTA CCA AAA GTT TTG2077Phe Thr Pro Glu Leu Ala Ser Cys Ser Thr Ly - #s Leu Pro Lys Val Leu# 670- GTA GTG CTA CCC TTA GCA TCA AAC CGA AGC TA - #C GTT ATA ACT CGT ACT2125Val Val Leu Pro Leu Ala Ser Asn Arg Ser Ty - #r Val Ile Thr Arg Thr# 685- GCG CCC AAT ATA GGT TTA ACT TAC TCT CTT GA - #T GGG GTA AAT ATA GCA2173Ala Pro Asn Ile Gly Leu Thr Tyr Ser Leu As - #p Gly Val Asn Ile Ala# 700- AAG CCT ATA GTC ATC AGT TAC ATC ACT TAT GG - #A AAT TGT CAA GTT TCG2221Lys Pro Ile Val Ile Ser Tyr Ile Thr Tyr Gl - #y Asn Cys Gln Val Ser# 715- AGA GCT ACA ATC AGG TCA GTT TAC TTG GAC CA - #T CCG GGC CAC ACC CAG2269Arg Ala Thr Ile Arg Ser Val Tyr Leu Asp Hi - #s Pro Gly His Thr Gln720 7 - #25 7 - #30 7 -#35- TCG TGC GTA TAT TGC GGG AGT GTG TTT ATG CG - #G TAT ATG GCA TCC GGA2317Ser Cys Val Tyr Cys Gly Ser Val Phe Met Ar - #g Tyr Met Ala Ser Gly# 750- GCA ATT ATG GAT TTG ATA TAC ATA GAT GAC AA - #A GAT GTA GAG TTG CAA2365Ala Ile Met Asp Leu Ile Tyr Ile Asp Asp Ly - #s Asp Val Glu Leu Gln# 765- CTG GTA GCA GGG GAA AAC TCA ACT ATT CCA GC - #C TTT AAC CCA AAG CTG2413Leu Val Ala Gly Glu Asn Ser Thr Ile Pro Al - #a Phe Asn Pro Lys Leu# 780- TAT ACG CCC AGC ATG AAT GCT CTT TTA ATG TT - #T CCA AAC GGA ACA GTA2461Tyr Thr Pro Ser Met Asn Ala Leu Leu Met Ph - #e Pro Asn Gly Thr Val# 795- ACC CTA ATG TCT GCA TTT GCA TCC TAC TCA GC - #T TTT AAA ATT CCC AGT2509Thr Leu Met Ser Ala Phe Ala Ser Tyr Ser Al - #a Phe Lys Ile Pro Ser800 8 - #05 8 - #10 8 -#15- ACT TAT CTG TGG GCT TCT ATT GGG GGT TTG TT - #G CTG GCT ATT CTG ATT2557Thr Tyr Leu Trp Ala Ser Ile Gly Gly Leu Le - #u Leu Ala Ile Leu Ile# 830- TTA TAT GTA ATC GTT AAA ATG TTA TGT GGT GG - #T GTA ATT AAT AAT GAC2605Leu Tyr Val Ile Val Lys Met Leu Cys Gly Gl - #y Val Ile Asn Asn Asp# 845- TAT AGT TTG TTA TTA AAC TCT GAG TAAACACAAA CA - #ATGTCTAG TGTGTTGTAT2659Tyr Ser Leu Leu Leu Asn Ser Glu# 855- TGCGTGTAAA CAGTATACGA GTGAACATTT ATACGTAAAA TGGTTAAATT TT - #ATTTTCGC2719# 2730- (2) INFORMATION FOR SEQ ID NO:2:- (i) SEQUENCE CHARACTERISTICS:#acids (A) LENGTH: 855 amino (B) TYPE: amino acid (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: protein- (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:- Met Ser Gln Pro Tyr Leu Lys Ile Ala Ile Le - #u Val Ala Ala Thr Ile# 15- Val Ser Ala Ile Pro Val Trp Thr Thr Pro Va - #l Ser Thr Ser Pro Pro# 30- Gln Gln Thr Lys Leu His Tyr Val Gly Asn Gl - #y Thr Trp Val His Asn# 45- Asn Thr Phe Asn Val Thr Arg Tyr Asp Arg Il - #e Thr Met Glu Pro Val# 60- Tyr Asn Asn Asn Leu Ser Ser Thr Thr Phe Ph - #e Val Ala Ile Ser Glu# 80- Arg Asn Phe Arg Thr Val Asn Thr Pro Leu Gl - #y Ala Ser Val Phe Trp# 95- Ile Leu Lys Ser Ala Leu Asn Pro Pro Lys Hi - #s Gln Pro Cys Ile Ala# 110- Asn Val Pro Glu Pro Gly Asp Pro Arg Gly Pr - #o Cys Val Asn Ser Thr# 125- Val Ser Leu Phe Phe Asn Asp Asn Leu Glu Pr - #o Phe Leu Met Thr Lys# 140- Asn Leu Leu Glu Phe Glu Val Leu Pro Asp As - #n Tyr Ile Thr Gly Trp145 1 - #50 1 - #55 1 -#60- Thr Phe Glu Arg Ser Lys Thr Val Ala Thr Ly - #s Gly Asn Pro Val Gly# 175- Val Val Leu Ser Pro Pro Arg Thr Ser Pro As - #p Val Asn Asn Thr Ile# 190- Arg Asp Asp Gly Thr Pro Lys Gln His Leu Se - #r Ile Ile Asp Glu His# 205- Thr Thr Phe Val Leu Asp Leu Gln Asn Phe Th - #r Lys Thr Leu Thr Tyr# 220- Ile Ser Pro Phe Ala Ala Val Trp Pro Ile Th - #r Ala Phe His Ala Gly225 2 - #30 2 - #35 2 -#40- Ile Thr Val Met Gly Cys Asp Thr Thr Gln Al - #a Ile Ala Tyr Leu Gly# 255- Asn Gly Phe Met Gly Leu Gln Ile Ser Ser Va - #l Asn Asn Pro Pro Leu# 270- Glu Met Ile Val Ala Pro Asn Asp Val Arg Al - #a Arg Ile Val Asn Arg# 285- Leu Pro Pro Arg Arg Arg Leu Glu Pro Pro Gl - #y Pro Tyr Ala Gly Pro# 300- Ile Tyr Lys Val Tyr Val Leu Ser Asp Gly As - #n Phe Tyr Leu Gly His305 3 - #10 3 - #15 3 -#20- Gly Met Ser Lys Ile Ser Arg Glu Val Ala Al - #a Tyr Pro Glu Glu Ser# 335- Leu Asp Tyr Arg Tyr His Leu Ser Leu Ala As - #n Leu Asp Thr Leu Ala# 350- Met Leu Ala Glu Leu Ser Ser Gly Lys Ser Ly - #s Asp Val Ser Tyr Tyr# 365- Leu Tyr Arg Ile Ile Ala Arg Leu Ala Val Al - #a Thr Phe Ser Leu Ala# 380- Glu Val Ile Arg Leu Ser Asp Tyr Met Leu Le - #u Gln Glu Ala Ile Asp385 3 - #90 3 - #95 4 -#00- Val Asp Ile Asn Leu Arg Leu Ile Val Pro Le - #u Val Met Lys Tyr Ala# 415- Ala Gly Gly Thr Ala Asp Ser Ser Tyr Thr Se - #r Ser Asp Val Ala Met# 430- Asp Gln Phe Glu Val Ala Gln Ala Gln Ile Gl - #u Lys Ile Val Ala Asp# 445- Ile Asn Ile Glu Asn Glu Leu Arg Lys Pro Me - #t Tyr Glu His Arg Ser# 460- Leu Leu Lys Ser Val Tyr Ala Tyr Ser Arg Ly - #s Pro Leu Pro Asn Ala465 4 - #70 4 - #75 4 -#80- Val Ser Phe Ala Asn Arg Leu Ile Thr Ala Me - #t Tyr Lys Glu Ala Ile# 495- Lys Asp Arg Ile Thr Trp Asn Ser Thr Met Ar - #g Glu Val Leu Phe Phe# 510- Ala Val Gly Ala Ala Ala Gly Ser His Val Il - #e Leu Thr Asp Gly Pro# 525- Asp Leu Gly Leu His Ala His Lys Asp Ser Se - #r Met Phe Leu Ser Leu# 540- Asn Arg Asn Ile Leu Leu Leu Cys Thr Ala Me - #t Cys Thr Ala Ser His545 5 - #50 5 - #55 5 -#60- Ala Val Ser Ala Gly Val Lys Leu Glu Glu Va - #l Met Ala Gly Leu Ile# 575- Ala Gly Gly Val Gln Phe Ser Leu Leu Glu Va - #l Phe Ser Pro Cys Met# 590- Ala Ser Ala Arg Phe Asp Leu Ala Glu Glu Gl - #u His Val Leu Asp Leu# 605- Leu Ser Val Ile Pro Pro Arg Leu Tyr Thr As - #p Leu Asn Thr Gly Leu# 620- Glu Asp Asp Gly Thr Thr Ile His Ser Tyr Gl - #y Arg Ser Ala Asn Gly625 6 - #30 6 - #35 6 -#40- Ile Leu Asn Ser Arg Ile Ala Tyr Asn Phe As - #p Ala Val Arg Val Phe# 655- Thr Pro Glu Leu Ala Ser Cys Ser Thr Lys Le - #u Pro Lys Val Leu Val# 670- Val Leu Pro Leu Ala Ser Asn Arg Ser Tyr Va - #l Ile Thr Arg Thr Ala# 685- Pro Asn Ile Gly Leu Thr Tyr Ser Leu Asp Gl - #y Val Asn Ile Ala Lys# 700- Pro Ile Val Ile Ser Tyr Ile Thr Tyr Gly As - #n Cys Gln Val Ser Arg705 7 - #10 7 - #15 7 -#20- Ala Thr Ile Arg Ser Val Tyr Leu Asp His Pr - #o Gly His Thr Gln Ser# 735- Cys Val Tyr Cys Gly Ser Val Phe Met Arg Ty - #r Met Ala Ser Gly Ala# 750- Ile Met Asp Leu Ile Tyr Ile Asp Asp Lys As - #p Val Glu Leu Gln Leu# 765- Val Ala Gly Glu Asn Ser Thr Ile Pro Ala Ph - #e Asn Pro Lys Leu Tyr# 780- Thr Pro Ser Met Asn Ala Leu Leu Met Phe Pr - #o Asn Gly Thr Val Thr785 7 - #90 7 - #95 8 -#00- Leu Met Ser Ala Phe Ala Ser Tyr Ser Ala Ph - #e Lys Ile Pro Ser Thr# 815- Tyr Leu Trp Ala Ser Ile Gly Gly Leu Leu Le - #u Ala Ile Leu Ile Leu# 830- Tyr Val Ile Val Lys Met Leu Cys Gly Gly Va - #l Ile Asn Asn Asp Tyr# 845- Ser Leu Leu Leu Asn Ser Glu# 855- (2) INFORMATION FOR SEQ ID NO:3:- (i) SEQUENCE CHARACTERISTICS:#pairs (A) LENGTH: 1560 base (B) TYPE: nucleic acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: DNA (genomic)- (ix) FEATURE: (A) NAME/KEY: CDS (B) LOCATION: 52..1506- (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:#ATG GGT 57GTTCTTT GTGGAAAATC GCAAACATAT AACCCACAGC A# Met Gly# 1- TTG GTA AAT ATA ATG CGA TTC ATA ACA TTT GC - #G TAT ATA ATC TGT GGG 105Leu Val Asn Ile Met Arg Phe Ile Thr Phe Al - #a Tyr Ile Ile Cys Gly# 15- GGG TTT ATA TTA ACA CGC ACG TCT GGG ACC AG - #T GCT AGC GCC AGT CCA 153Gly Phe Ile Leu Thr Arg Thr Ser Gly Thr Se - #r Ala Ser Ala Ser Pro# 30- GCC ACA CCA ACC ACA AAT ACT GGC GAA GGC AC - #C AGT TCT CCA GTC ACA 201Ala Thr Pro Thr Thr Asn Thr Gly Glu Gly Th - #r Ser Ser Pro Val Thr# 50- CCA ACT TAC ACA ACC AGT ACG GAC TCT AAT AA - #T TCA ACA GCC ACG AAC 249Pro Thr Tyr Thr Thr Ser Thr Asp Ser Asn As - #n Ser Thr Ala Thr Asn# 65- AAC TCA ACC GAT GTA AAC GGC ACC GAA GCT AC - #A CCA ACG CCG AGT CAC 297Asn Ser Thr Asp Val Asn Gly Thr Glu Ala Th - #r Pro Thr Pro Ser His# 80- CCA CAT TCA CAT GAA AAT ACA ATT ACA TGC AC - #A AAT AGT CTC ATA TCG 345Pro His Ser His Glu Asn Thr Ile Thr Cys Th - #r Asn Ser Leu Ile Ser# 95- GTT CCC TAC TAC ACA TCT GTT ACC ATT AAC TG - #T TCT ACA ACA GTA AGT 393Val Pro Tyr Tyr Thr Ser Val Thr Ile Asn Cy - #s Ser Thr Thr Val Ser# 110- GTA AAT CAC AGT GAA TAC AGA CTA GAA ATT CA - #C CTA AAC CAG CGC ACC 441Val Asn His Ser Glu Tyr Arg Leu Glu Ile Hi - #s Leu Asn Gln Arg Thr115 1 - #20 1 - #25 1 -#30- CCA TTT TCA GAC ACG CCT CCT GGT GAC CAA GA - #A AAC TAT GTT AAC CAC 489Pro Phe Ser Asp Thr Pro Pro Gly Asp Gln Gl - #u Asn Tyr Val Asn His# 145- AAC GCT ACC AAA GAC CAA ACC CTG CTG TTA TT - #T TCA ACC GCA CAT TCT 537Asn Ala Thr Lys Asp Gln Thr Leu Leu Leu Ph - #e Ser Thr Ala His Ser# 160- AGC GCG AAA TCT CGA AGG GTT GGC CAG CTG GG - #C GTT ATT CCA GAC AGG 585Ser Ala Lys Ser Arg Arg Val Gly Gln Leu Gl - #y Val Ile Pro Asp Arg# 175- CTA CCT AAG CGT CAA CTG TTC AAC CTC CCG GC - #C CAC ACG AAC GGT GGT 633Leu Pro Lys Arg Gln Leu Phe Asn Leu Pro Al - #a His Thr Asn Gly Gly# 190- ACA AAT TTT CCA CTA AAC ATA AAA TCT ATA GA - #C TGG CGT ACC GCG GGA 681Thr Asn Phe Pro Leu Asn Ile Lys Ser Ile As - #p Trp Arg Thr Ala Gly195 2 - #00 2 - #05 2 -#10- GTT TAT GTG TGG TAC TTG TTT GCC AAA AAC GG - #C TCA CTC ATT AAC AGT 729Val Tyr Val Trp Tyr Leu Phe Ala Lys Asn Gl - #y Ser Leu Ile Asn Ser# 225- ACC AGC GTT ACC GTG TTA ACG TAC AAC GCA CC - #C CTA ATG GAC CTC TCC 777Thr Ser Val Thr Val Leu Thr Tyr Asn Ala Pr - #o Leu Met Asp Leu Ser# 240- GTT CAC CCA AGT TTG AAG GGT GAA AAC CAC AG - #A GCC GTG TGC GTA GTT 825Val His Pro Ser Leu Lys Gly Glu Asn His Ar - #g Ala Val Cys Val Val# 255- GCT AGC TAC TTT CCC CAC AAC TCT GTT AAG CT - #G AGG TGG TAT AAA AAC 873Ala Ser Tyr Phe Pro His Asn Ser Val Lys Le - #u Arg Trp Tyr Lys Asn# 270- GCC AAA GAG GTT GAT TTT ACA AAG TAT GTT AC - #C AAT GCT TCT AGT GTG 921Ala Lys Glu Val Asp Phe Thr Lys Tyr Val Th - #r Asn Ala Ser Ser Val275 2 - #80 2 - #85 2 -#90- TGG GTG GAT GGT CTC ATC ACT CGC ATC TCG AC - #T GTA TCA ATC CCA GCT 969Trp Val Asp Gly Leu Ile Thr Arg Ile Ser Th - #r Val Ser Ile Pro Ala# 305- GAC CCC GAC GAA GAA TAT CCC CCC AGC CTC CG - #C TGT AGC ATA GAA TGG1017Asp Pro Asp Glu Glu Tyr Pro Pro Ser Leu Ar - #g Cys Ser Ile Glu Trp# 320- TAC AGA GAC GAG GTA TCC TTT TCT CGC ATG GC - #C AAA GCA GGC ACG CCC1065Tyr Arg Asp Glu Val Ser Phe Ser Arg Met Al - #a Lys Ala Gly Thr Pro# 335- TCT GTG TTC GTG GCC CCA ACC GTG TCC GTA AA - #C GTT GAA GAT GGT GCA1113Ser Val Phe Val Ala Pro Thr Val Ser Val As - #n Val Glu Asp Gly Ala# 350- GCA GTT TGT ACG GCA GAA TGT GTA CCT AGC AA - #C GGA GTG TTT GTA TCG1161Ala Val Cys Thr Ala Glu Cys Val Pro Ser As - #n Gly Val Phe Val Ser355 3 - #60 3 - #65 3 -#70- TGG GTC GTT AAC GAC CAT TTA CCG GGG GTC CC - #A TCA CAA GAC GTA ACA1209Trp Val Val Asn Asp His Leu Pro Gly Val Pr - #o Ser Gln Asp Val Thr# 385- ACG GGA GTT TGC TCA AGC CAC CCA GGA TTA GT - #C AAC ATG CGG AGT AGC1257Thr Gly Val Cys Ser Ser His Pro Gly Leu Va - #l Asn Met Arg Ser Ser# 400- AGG CCC CTG TCG GAA GAA AAC GGA GAG CGA GA - #G TAT AAC TGC ATC ATA1305Arg Pro Leu Ser Glu Glu Asn Gly Glu Arg Gl - #u Tyr Asn Cys Ile Ile# 415- GAG GGT TAC CCG GAC GGC CTT CCA ATG TTT TC - #T GAC AGC GTT GTA TAT1353Glu Gly Tyr Pro Asp Gly Leu Pro Met Phe Se - #r Asp Ser Val Val Tyr# 430- GAT GCA TCC CCT ATT GTT GAG GAC ATG CCC GT - #T TTA ACT GGC ATC ATC1401Asp Ala Ser Pro Ile Val Glu Asp Met Pro Va - #l Leu Thr Gly Ile Ile435 4 - #40 4 - #45 4 -#50- GCC GTT ACT TGC GGG GCC GCA GCG CTA GCG CT - #G GTT GTT CTC ATT ACA1449Ala Val Thr Cys Gly Ala Ala Ala Leu Ala Le - #u Val Val Leu Ile Thr# 465- GCC GTT TGT TTT TAC TGC TCA AAA CCC TCG CA - #G GTG CCG TAC AAG AAA1497Ala Val Cys Phe Tyr Cys Ser Lys Pro Ser Gl - #n Val Pro Tyr Lys Lys# 480- GCA GAC TTC TAAGCTCGTC GTCAGTTTGA ACAGCAGCTG GTTTTTTTA - #A1546Ala Asp Phe 485# 1560- (2) INFORMATION FOR SEQ ID NO:4:- (i) SEQUENCE CHARACTERISTICS:#acids (A) LENGTH: 485 amino (B) TYPE: amino acid (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: protein- (xi) SEQUENCE DESCRIPTION: SEQ ID NO:4:- Met Gly Leu Val Asn Ile Met Arg Phe Ile Th - #r Phe Ala Tyr Ile Ile# 15- Cys Gly Gly Phe Ile Leu Thr Arg Thr Ser Gl - #y Thr Ser Ala Ser Ala# 30- Ser Pro Ala Thr Pro Thr Thr Asn Thr Gly Gl - #u Gly Thr Ser Ser Pro# 45- Val Thr Pro Thr Tyr Thr Thr Ser Thr Asp Se - #r Asn Asn Ser Thr Ala# 60- Thr Asn Asn Ser Thr Asp Val Asn Gly Thr Gl - #u Ala Thr Pro Thr Pro# 80- Ser His Pro His Ser His Glu Asn Thr Ile Th - #r Cys Thr Asn Ser Leu# 95- Ile Ser Val Pro Tyr Tyr Thr Ser Val Thr Il - #e Asn Cys Ser Thr Thr# 110- Val Ser Val Asn His Ser Glu Tyr Arg Leu Gl - #u Ile His Leu Asn Gln# 125- Arg Thr Pro Phe Ser Asp Thr Pro Pro Gly As - #p Gln Glu Asn Tyr Val# 140- Asn His Asn Ala Thr Lys Asp Gln Thr Leu Le - #u Leu Phe Ser Thr Ala145 1 - #50 1 - #55 1 -#60- His Ser Ser Ala Lys Ser Arg Arg Val Gly Gl - #n Leu Gly Val Ile Pro# 175- Asp Arg Leu Pro Lys Arg Gln Leu Phe Asn Le - #u Pro Ala His Thr Asn# 190- Gly Gly Thr Asn Phe Pro Leu Asn Ile Lys Se - #r Ile Asp Trp Arg Thr# 205- Ala Gly Val Tyr Val Trp Tyr Leu Phe Ala Ly - #s Asn Gly Ser Leu Ile# 220- Asn Ser Thr Ser Val Thr Val Leu Thr Tyr As - #n Ala Pro Leu Met Asp225 2 - #30 2 - #35 2 -#40- Leu Ser Val His Pro Ser Leu Lys Gly Glu As - #n His Arg Ala Val Cys# 255- Val Val Ala Ser Tyr Phe Pro His Asn Ser Va - #l Lys Leu Arg Trp Tyr# 270- Lys Asn Ala Lys Glu Val Asp Phe Thr Lys Ty - #r Val Thr Asn Ala Ser# 285- Ser Val Trp Val Asp Gly Leu Ile Thr Arg Il - #e Ser Thr Val Ser Ile# 300- Pro Ala Asp Pro Asp Glu Glu Tyr Pro Pro Se - #r Leu Arg Cys Ser Ile305 3 - #10 3 - #15 3 -#20- Glu Trp Tyr Arg Asp Glu Val Ser Phe Ser Ar - #g Met Ala Lys Ala Gly# 335- Thr Pro Ser Val Phe Val Ala Pro Thr Val Se - #r Val Asn Val Glu Asp# 350- Gly Ala Ala Val Cys Thr Ala Glu Cys Val Pr - #o Ser Asn Gly Val Phe# 365- Val Ser Trp Val Val Asn Asp His Leu Pro Gl - #y Val Pro Ser Gln Asp# 380- Val Thr Thr Gly Val Cys Ser Ser His Pro Gl - #y Leu Val Asn Met Arg385 3 - #90 3 - #95 4 -#00- Ser Ser Arg Pro Leu Ser Glu Glu Asn Gly Gl - #u Arg Glu Tyr Asn Cys# 415- Ile Ile Glu Gly Tyr Pro Asp Gly Leu Pro Me - #t Phe Ser Asp Ser Val# 430- Val Tyr Asp Ala Ser Pro Ile Val Glu Asp Me - #t Pro Val Leu Thr Gly# 445- Ile Ile Ala Val Thr Cys Gly Ala Ala Ala Le - #u Ala Leu Val Val Leu# 460- Ile Thr Ala Val Cys Phe Tyr Cys Ser Lys Pr - #o Ser Gln Val Pro Tyr465 4 - #70 4 - #75 4 -#80- Lys Lys Ala Asp Phe 485- (2) INFORMATION FOR SEQ ID NO:5:- (i) SEQUENCE CHARACTERISTICS:#acids (A) LENGTH: 855 amino (B) TYPE: amino acid (C) STRANDEDNESS: single (D) TOPOLOGY: linear- (ii) MOLECULE TYPE: peptide- (xi) SEQUENCE DESCRIPTION: SEQ ID NO:5:- Met Ser Glu Pro Tyr Leu Lys Ile Ala Ile Le - #u Val Ala Ala Thr Ile# 15- Val Ser Ala Ile Pro Val Trp Thr Thr Pro Va - #l Ser Thr Ser Pro Pro# 30- Glu Glu Thr Lys Leu His Tyr Val Gly Asn Gl - #y Thr Trp Val His Asn# 45- Asn Thr Phe Asn Val Thr Arg Tyr Asp Arg Il - #e Thr Met Glu Pro Val# 60- Tyr Asn Asn Asn Leu Ser Ser Thr Thr Phe Ph - #e Val Ala Ile Ser Glu#80- Arg Asn Phe Arg Thr Val Asn Thr Pro Leu Gl - #y Ala Ser Val Phe Trp# 95- Ile Leu Lys Ser Ala Leu Asn Pro Pro Lys Hi - #s Glu Pro Cys Ile Ala# 110- Asn Val Pro Glu Pro Gly Asp Pro Arg Gly Pr - #o Cys Val Asn Ser Thr# 125- Val Ser Leu Phe Phe Asn Asp Asn Leu Glu Pr - #o Phe Leu Met Thr Lys# 140- Asn Leu Leu Glu Phe Glu Val Leu Pro Asp As - #n Tyr Ile Thr Gly Trp145 1 - #50 1 - #55 1 -#60- Thr Phe Glu Arg Ser Lys Thr Val Ala Thr Ly - #s Gly Asn Pro Val Gly# 175- Val Val Leu Ser Pro Pro Arg Thr Ser Pro As - #p Val Asn Asn Thr Ile# 190- Arg Asp Asp Gly Thr Pro Lys Glu His Leu Se - #r Ile Ile Asp Glu His# 205- Thr Thr Phe Val Leu Asp Leu Gln Asn Phe Th - #r Lys Thr Leu Thr Tyr# 220- Ile Ser Pro Phe Ala Ala Val Trp Pro Ile Th - #r Ala Phe His Ala Gly225 2 - #30 2 - #35 2 -#40- Ile Thr Val Met Gly Cys Asp Thr Thr Glu Al - #a Ile Ala Tyr Leu Gly# 255- Asn Gly Phe Met Gly Leu Glu Ile Ser Ser Va - #l Asn Asn Pro Pro Leu# 270- Glu Met Ile Val Ala Pro Asn Asp Val Arg Al - #a Arg Ile Val Asn Arg# 285- Leu Pro Pro Arg Arg Arg Leu Glu Pro Pro Gl - #y Pro Tyr Ala Gly Pro# 300- Ile Tyr Lys Val Tyr Val Leu Ser Asp Gly As - #n Phe Tyr Leu Gly His305 3 - #10 3 - #15 3 -#20- Gly Met Ser Lys Ile Ser Arg Glu Val Ala Al - #a Tyr Pro Glu Glu Ser# 335- Leu Asp Tyr Arg Tyr His Leu Ser Leu Ala As - #n Leu Asp Thr Leu Ala# 350- Met Leu Ala Glu Leu Ser Ser Gly Lys Ser Ly - #s Asp Val Ser Tyr Tyr# 365- Leu Tyr Arg Ile Ile Ala Arg Leu Ala Val Al - #a Thr Phe Ser Leu Ala# 380- Glu Val Ile Arg Leu Ser Asp Tyr Met Leu Le - #u Gln Glu Ala Ile Asp385 3 - #90 3 - #95 4 -#00- Val Asp Ile Asn Leu Arg Leu Ile Val Pro Le - #u Val Met Lys Tyr Ala# 415- Ala Gly Gly Thr Ala Asp Ser Ser Tyr Thr Se - #r Ser Asp Val Ala Met# 430- Asp Gln Phe Glu Val Ala Gln Ala Gln Ile Gl - #u Lys Ile Val Ala Asp# 445- Ile Asn Ile Glu Asn Glu Leu Arg Lys Pro Me - #t Tyr Glu His Arg Ser# 460- Leu Leu Lys Ser Val Tyr Ala Tyr Ser Arg Ly - #s Pro Leu Pro Asn Ala465 4 - #70 4 - #75 4 -#80- Val Ser Phe Ala Asn Arg Leu Ile Thr Ala Me - #t Tyr Lys Glu Ala Ile# 495- Lys Asp Arg Ile Thr Trp Asn Ser Thr Met Ar - #g Glu Val Leu Phe Phe# 510- Ala Val Gly Ala Ala Ala Gly Ser His Val Il - #e Leu Thr Asp Gly Pro# 525- Asp Leu Gly Leu His Ala His Lys Asp Ser Se - #r Met Phe Leu Ser Leu# 540- Asn Arg Asn Ile Leu Leu Leu Cys Thr Ala Me - #t Cys Thr Ala Ser His545 5 - #50 5 - #55 5 -#60- Ala Val Ser Ala Gly Val Lys Leu Glu Glu Va - #l Met Ala Gly Leu Ile# 575- Ala Gly Gly Val Gln Phe Ser Leu Leu Glu Va - #l Phe Ser Pro Cys Met# 590- Ala Ser Ala Arg Phe Asp Leu Ala Glu Glu Gl - #u His Val Leu Asp Leu# 605- Leu Ser Val Ile Pro Pro Arg Leu Tyr Thr As - #p Leu Asn Thr Gly Leu# 620- Glu Asp Asp Gly Thr Thr Ile His Ser Tyr Gl - #y Arg Ser Ala Asn Gly625 6 - #30 6 - #35 6 -#40- Ile Leu Asn Ser Arg Ile Ala Tyr Asn Phe As - #p Ala Val Arg Val Phe# 655- Thr Pro Glu Leu Ala Ser Cys Ser Thr Lys Le - #u Pro Lys Val Leu Val# 670- Val Leu Pro Leu Ala Ser Asn Arg Ser Tyr Va - #l Ile Thr Arg Thr Ala# 685- Pro Asn Ile Gly Leu Thr Tyr Ser Leu Asp Gl - #y Val Asn Ile Ala Lys# 700- Pro Ile Val Ile Ser Tyr Ile Thr Tyr Gly As - #n Cys Gln Val Ser Arg705 7 - #10 7 - #15 7 -#20- Ala Thr Ile Arg Ser Val Tyr Leu Asp His Pr - #o Gly His Thr Gln Ser# 735- Cys Val Tyr Cys Gly Ser Val Phe Met Arg Ty - #r Met Ala Ser Gly Ala# 750- Ile Met Asp Leu Ile Tyr Ile Asp Asp Lys As - #p Val Glu Leu Gln Leu# 765- Val Ala Gly Glu Asn Ser Thr Ile Pro Ala Ph - #e Asn Pro Lys Leu Tyr# 780- Thr Pro Ser Met Asn Ala Leu Leu Met Phe Pr - #o Asn Gly Thr Val Thr785 7 - #90 7 - #95 8 -#00- Leu Met Ser Ala Phe Ala Ser Tyr Ser Ala Ph - #e Lys Ile Pro Ser Thr# 815- Tyr Leu Trp Ala Ser Ile Gly Gly Leu Leu Le - #u Ala Ile Leu Ile Leu# 830- Tyr Val Ile Val Lys Met Leu Cys Gly Gly Va - #l Ile Asn Asn Asp Tyr# 845- Ser Leu Leu Leu Asn Ser Glu# 855__________________________________________________________________________

Claims

1. An isolated polypeptide encoding native equine herpes virus-4 glycoprotein H (EHV-4 gH) or an antigenic fragment thereof.

2. An isolated polypeptide comprising an amino acid sequence having SEQ ID NO: 2 or an antigenic fragment thereof.

3. An isolated polypeptide encoded by a nucleic acid having SEQ ID NO: 1.

4. A vaccine for the protection of horses against EHV-4 infection, wherein the vaccine comprises a polypeptide according to any one of claims 1 to 3 in a pharmaceutically acceptable carrier.

5. A method for the preparation of an EHV-4 vaccine, comprising the steps of:

a) providing a polypeptide set forth in any one of claims 1 to 3;

b) providing a pharmaceutically acceptable carrier; and

c) combining said polypeptide of a) and said carrier of b) to a vaccine preparation with immunizing activity against EHV-4.

6. A method for the protection of a horse against EHV-4 infection wherein an effective amount of a vaccine according to claim 4 is administered to said horse.

7. An isolated polypeptide encoding native equine herpes virus-4 glycoprotein C (EHV-4 gC) or an antigenic fragment thereof.

8. An isolated polypeptide comprising an amino acid sequence as set forth in SEQ ID NO: 4, or an antigenic fragment thereof.

9. An isolated polypeptide encoded by a nucleic acid as set forth in SEQ ID NO: 3.

10. A vaccine for the protection of horses against EHV-4 infection, wherein the vaccine comprises a polypeptide according to any one of claims 7 to 9 in a pharmaceutically acceptable carrier.

11. A method for the preparation of an EHV-4 vaccine, comprising the steps of::

a) providing a polypeptide set forth in any one of claims 7 to 9;

b) providing a pharmaceutically acceptable carrier; and

c) combining said polypeptide of a) and said carrier of b) to a vaccine preparation with immunizing activity against EHV-4.

12. A method for the protection of a horse against EHV-4 infection wherein an effective amount of a vaccine according to claim 10 is administered to said horse.