KR102544928B1 - Composition for improving stability of antigen for animal vaccine or diagnosis comprising amino acid as effective component and uses thereof - Google Patents

Abstract

The present invention relates to a composition for enhancing the stability of an animal vaccine or diagnostic antigen containing amino acids as an active ingredient, and its use. Since the titer can be effectively maintained and the transportation and storage of the vaccine can be facilitated, it will be usefully used in related fields.

Description

Composition for improving stability of antigen for animal vaccine or diagnosis comprising amino acid as effective component and uses thereof

The present invention relates to a composition for enhancing the stability of an animal vaccine or diagnostic antigen containing amino acids as an active ingredient and its use.

In the case of a vaccine using a virus or viral vector as an immunogen (antigen), there are cases where the stability of the immunogen is not guaranteed due to the agitation and freeze-thawing steps that occur during the manufacturing process and the storage temperature after manufacturing. there is.

Vaccine stabilizers are chemical compounds that are added to vaccine formulations to improve the stability of vaccines during lyophilization processing or storage after lyophilization, and are well known in the art. These stabilizer components are used alone or in combination with multiple components, and function to preserve the ability of immunogens (e.g., viruses) during vaccine production or storage, and to prevent aggregation of immunogens during the freezing process.

Since the attenuated virus vaccine shows its effect mainly by cellular immunity, it shows a long-term immune effect even with a single inoculation compared to the dead poison vaccine, which relies on humoral immunity. Attenuated viruses used in vaccines are sensitive to heat and cannot easily maintain their activity at high temperatures. In addition, since antigenicity can be lost not only by heat but also by various physical and chemical stimuli, various methods for maintaining the titer of the virus must be considered in order to maintain the efficacy of the vaccine.

In the use of bait vaccines for public interest, such as rabies and African swine fever, the virus contained in the bait has the characteristic of being exposed and supplied at room temperature, so the decrease in virus titer due to temperature is a type of vaccine that is of great concern. The shelf life of temperature-sensitive virus vaccines can be improved through the development of stabilizers.

Meanwhile, Korean Patent Registration No. 1679723 discloses 'a vaccine composition containing a stabilizer and one or more live attenuated flaviviruses', and Korean Patent Publication No. 2018-0135912 discloses 'Alphabe using an improved formulation'. Virus stabilization composition and method' is disclosed, but there is no description of the 'composition for enhancing the stability of an animal vaccine or diagnostic antigen containing amino acids as an active ingredient and its use' of the present invention.

The present invention has been derived from the above needs, and the present inventors have developed a combination of various amino acids in an animal vaccine using a virus as an immunogen, in order to suppress the inactivation and decrease in titer of the virus during freeze-thaw or storage after manufacture. It was intended to provide a stabilizer for a vaccine composition comprising

The present inventor prepared a stabilizer for a vaccine composition composed of 12 amino acids including glutamic acid, and then confirmed the viability of the virus according to the use of the stabilizer for ssRNA virus and dsDNA virus. As a result, the stabilizer prepared in the present invention The present invention was completed by confirming that the low-temperature / room temperature storage stability and stability against freeze-thaw stress were imparted.

In order to solve the above problems, the present invention is glutamic acid, methionine, valine, glutamine, asparagine, histidine, serine, alanine , It provides a composition for improving the stability of an animal vaccine or diagnostic antigen, including glycine, threonine, proline, arginine and aspartic acid as active ingredients.

In addition, the present invention provides a composition for enhancing the stability of the animal vaccine or diagnostic antigen, and a vaccine composition comprising one or more antigens.

In addition, the present invention comprises the steps of preparing a vaccine antigen for animals; and mixing the prepared animal vaccine antigen with the composition for enhancing the stability of the animal vaccine or diagnostic antigen of the present invention.

The composition for enhancing the stability of an antigen of the present invention has an effect of stabilizing a virus, which is an antigen (immunogen), during the vaccine manufacturing process including agitation and freeze-thawing and storage, so that it is prophylactically effective in animal virus vaccines without loss of infectious titer. Since the virus titer can be effectively maintained and the transportation and storage of the vaccine can be facilitated, it will be usefully used in related fields.

Figure 1 is the result of confirming the viability of the virus (Akabane virus K-9 strain) mixed with the stabilizer (CVS) of the present invention at 4 ℃ or 25 ℃ conditions. Control is a 1X PBS addition group.
Figure 2 is the result of analyzing the effect of the stabilizing agent (CVS) of the present invention on the stabilization of the virus (Rabies virus ERAGS strain) at 4 ° C or 25 ° C conditions. Control is a 1X PBS addition group, Trehalose is a comparative control group to which 5% trehalose was added previously used.
Figure 3 is the result of analyzing the effect of the stabilizing agent (CVS) of the present invention on the stabilization of the virus (Japanese encephalitis virus KV1899 strain) under the condition of 25 ℃. Control is a 1X PBS addition group.
4 is a result of analyzing the effect of the stabilizing agent (CVS) of the present invention on the stabilization of a virus (Foot-and-mouth disease virus O1 Manisa strain) at 25°C. Control is a 1X PBS addition group, and Sucrose is a comparative control group with the addition of 5% sucrose previously used.
5 is a result of analyzing the effect of the stabilizing agent (CVS) of the present invention on the stabilization of the virus (recombinant Adeno virus KVCC-VR1500041) at 4°C. Control is a 1X PBS addition group, Trehalose is a comparative control group to which 5% trehalose was added previously used.
6 is a result of analyzing the effect of the stabilizer (CVS) of the present invention on the stabilization of the virus (African swine fever virus Yc1-Fc PSV strain) at 25 ° C. Control is a 1X PBS addition group.
7 is a result of analyzing the effect of the stabilizing agent (CVS) of the present invention on the stabilization of a virus (Aujeszky's disease virus YS400 strain) at 4 ° C or 25 ° C conditions. Control is a 1X PBS addition group.
8 is a result of analyzing the effect of the stabilizing agent (CVS) of the present invention on virus (Akabane virus) stabilization under repeated freezing and thawing conditions. Control is a 1X PBS addition group.

In order to achieve the object of the present invention, the present invention provides glutamic acid, methionine, valine, glutamine, asparagine, histidine, serine, alanine ( alanine), glycine, threonine, proline, arginine and aspartic acid as active ingredients, providing a composition for enhancing the stability of an animal vaccine or diagnostic antigen do.

The composition for enhancing the stability of an animal vaccine or diagnostic antigen according to the present invention contains 40 to 60 parts by weight of methionine, 40 to 60 parts by weight of valine, 40 to 60 parts by weight of glutamine, and 40 to 60 parts by weight of asparagine, based on 100 parts by weight of glutamic acid. , 40 to 60 parts by weight of histidine, 40 to 60 parts by weight of serine, 40 to 60 parts by weight of alanine, 40 to 60 parts by weight of glycine, 40 to 60 parts by weight of threonine, 40 to 60 parts by weight of proline, 40 to 60 parts by weight of arginine and 40 to 60 parts by weight of aspartic acid, more preferably 45 to 55 parts by weight of methionine, 45 to 55 parts by weight of valine, 45 to 55 parts by weight of glutamine, and 45 to 55 parts by weight of asparagine, based on 100 parts by weight of glutamic acid. 45 to 55 parts by weight of histidine, 45 to 55 parts by weight of serine, 45 to 55 parts by weight of alanine, 45 to 55 parts by weight of glycine, 45 to 55 parts by weight of threonine, 45 to 55 parts by weight of proline, 45 to 55 parts by weight of arginine and 45 to 55 parts by weight of aspartic acid, most preferably 50 parts by weight of methionine, 50 parts by weight of valine, 50 parts by weight of glutamine, 50 parts by weight of asparagine, 50 parts by weight of histidine, and 50 parts by weight of serine, based on 100 parts by weight of glutamic acid. It may consist of 50 parts by weight of alanine, 50 parts by weight of glycine, 50 parts by weight of threonine, 50 parts by weight of proline, 50 parts by weight of arginine, and 50 parts by weight of aspartic acid, but is not limited thereto.

In the present invention, the amino acid may include both D-type amino acids and L-type amino acids, preferably L-type amino acids, but is not limited thereto.

The preferred range of ingredients disclosed herein can be advantageously used to stabilize, among other features, stability against freeze-thaw stress and antigens that are immunogens of vaccines, and protection against heat-inactivation for long periods at room temperature.

In addition, in the composition for enhancing the stability of an animal vaccine or diagnostic antigen according to the present invention, the antigen may be whole cells or recombinant proteins derived from viruses, bacteria, or parasites that cause diseases in animals, but are not limited thereto. don't In addition, the whole cells of the virus, bacteria or parasite may include all live cells or cells inactivated by chemical/physical methods. Chemical inactivation can be carried out, for example, by treatment with enzymes, formaldehyde, beta-propiolactone, ethylene-imine or derivatives thereof, and physical inactivation can be performed by irradiation with energetic radiation, for example UV light. It may be performed, but is not limited thereto.

In the present invention, the term "antigen for vaccine" induces a sensitive and/or immune-reactive state as it is introduced into contact with appropriate cells, and in vivo ( in vivo ) or in vitro ( in vitro ) the immunity of a subject sensitized in this way. Any substance that reacts in a demonstrable manner with cells and/or antibodies. As used herein, the term "antigen" may be used in the same sense as the term "immunogen", and preferably can stimulate the host immune system to induce secretory, humoral and/or cellular immune responses specific to the antigen. A molecule containing one or more epitopes.

The present invention also provides a composition for enhancing the stability of an animal vaccine or diagnostic antigen according to the present invention and a vaccine composition comprising one or more antigens.

In the vaccine composition of the present invention, the composition for enhancing the stability of the animal vaccine or diagnostic antigen is as described above.

In the present invention, the term "vaccine" means a pharmaceutical composition having an immune function against an infectious disease.

In addition, in the vaccine composition of the present invention, the vaccine may be a vaccine whose antigen is a virus or a virus-derived recombinant protein, but is not limited thereto.

In the vaccine composition according to one embodiment of the present invention, the antigen is preferably a single-stranded negative RNA enveloped virus (ss(-)RNA enveloped virus), a single-stranded positive RNA enveloped virus (ss(+)RNA enveloped virus) virus, single-stranded positive RNA non-enveloped virus, dsDNA enveloped virus, or dsDNA non-enveloped virus ), more preferably Orthobunyavirus genus ( Orthobunyavirus ) or Lyssavirus genus ( Lyssavirus ) single-stranded negative RNA enveloped virus; Single-stranded positive RNA enveloped virus of the genus Flavivirus ; single-stranded positive RNA non-enveloped virus of the genus Aphthovirus ; double-stranded DNA non-enveloped virus of the family Adenoviridae; Or a double-stranded DNA enveloped virus of the genus Asfivirus or Varicellovirus ; most preferably, a single-stranded virus such as Akabane virus or Rabies virus. negative RNA enveloped viruses; single-stranded positive RNA enveloped viruses such as Japanese encephalitis virus; single-stranded positive RNA non-enveloped viruses such as foot-and-mouth disease virus; double-stranded DNA non-enveloped viruses such as adenovirus; or a double-stranded DNA enveloped virus such as African swine fever virus or Aujeszky's disease virus; but is not limited thereto. In addition, the virus may be a live virus, a live attenuated virus or an inactivated virus, but is not limited thereto.

In addition, a person skilled in the art can apply a change in the volume ratio of the composition for enhancing stability to the antigen in practicing the claimed invention, which is based on the titer or activity of the antigen as a vaccine immunogen, and the mixing ratio of the composition for enhancing stability. You will know for sure that it will require a change of Therefore, in order to produce a vaccine in the present invention, it is not limited to a 1:1 stability enhancing composition/antigen mixture.

In addition, the vaccine composition according to the present invention may further include a pharmaceutically acceptable carrier and/or adjuvant. In addition to the carrier and/or adjuvant, the vaccine composition of the present invention may further include an excipient and/or a diluent.

As used herein, the term "pharmaceutically acceptable" refers to a substance that is physiologically acceptable and does not cause an allergic reaction such as gastrointestinal disorder or dizziness or similar reaction when administered to a subject. Examples of the carrier, excipient and diluent include lactose, dextrose, sucrose, sorbitol, mannitol, xylitol, erythritol, maltitol, starch, acacia gum, alginate, gelatin, calcium phosphate, calcium silicate, cellulose, methyl cellulose, polyvinylpyrrolidone, water, methylhydroxybenzoate, propylhydroxybenzoate, talc, magnesium stearate and mineral oil. In addition, fillers, anti-coagulants, lubricants, wetting agents, flavoring agents, emulsifiers and preservatives may be further included.

In the present specification, the "adjuvant" refers to a substance or composition that is added to a vaccine or pharmaceutically active ingredients to increase and/or affect an immune response. Typically, a carrier or auxiliary substance for an immunogen and/or other pharmacologically active substance or composition is usually meant. Typically, the term 'adjuvant' is to be interpreted in a broad sense and refers to a wide range of substances capable of enhancing the immunogenicity of an antigen incorporated into or administered with the adjuvant. In addition, adjuvants are not limited thereto, and may be divided into immune potentiators, antigen delivery systems, or combinations thereof. The number of additives in a particular vaccine in the art varies and depends on the manufacturing process and intended use of the vaccine.

The vaccine composition of the present invention can be formulated using methods known in the art to enable rapid release, sustained or delayed release of the active ingredient when administered to a mammal. The formulation may be in liquid or lyophilized form, but is not limited thereto.

The present invention also comprises the steps of preparing an animal vaccine antigen; and mixing the prepared animal vaccine antigen with the composition for enhancing the stability of the animal vaccine or diagnostic antigen of the present invention.

In the production method of the present invention, the composition of the composition for enhancing stability and the type of antigen are as described above.

In addition, in the production method according to one embodiment of the present invention, the mixing may be performed at a volume ratio of the stability enhancing composition:antigen of 1:1 to 1:3, but is not limited thereto.

Hereinafter, the present invention will be described in detail by examples. However, the following examples are only to illustrate the present invention, and the content of the present invention is not limited to the following examples.

Preparation Example 1. Preparation of stabilizer for virus vaccine

The inventors of the present invention, with reference to Korean Patent Registration No. 1759694, intend to develop a stabilizer ( C AVAC V accine Stabilizer , CVS) capable of increasing the stability of antigens (immunogens) in vaccine compositions using viruses as immunogens (antigens). did After confirming the effect of the stabilizer in various concentration combinations, a stabilizer consisting of 13 amino acids was finally prepared according to the composition shown in Table 1 below. The stabilizer (CVS) was prepared based on 1 L of distilled water, adjusted to pH 6.5 to 7.0, and filtered through a filter before use. Each reagent was purchased from Sigma-Aldrich.

Virus Stabilizer Composition ingredient CVS L-Methionine 2.5% (w/v) L-Valine 2.5% (w/v) L-Glutamine 2.5% (w/v) L-Asparagine 2.5% (w/v) L-Histidine 2.5% (w/v) L-Serine 2.5% (w/v) L-Alanine 2.5% (w/v) L-Glycine 2.5% (w/v) L-Threonine 2.5% (w/v) L-Proline 2.5% (w/v) L-Arginine 2.5% (w/v) L-Aspartic Acid 2.5% (w/v) L-Glutamic Acid 5.0% (w/v)

Preparation Example 2. Preparation of a virus vaccine containing a stabilizing agent

In the present invention, single-stranded negative RNA enveloped viruses such as Akabane virus or rabies virus (ss(-)RNA enveloped virus); single-stranded positive RNA enveloped viruses such as Japanese encephalitis virus; single-stranded positive RNA non-enveloped viruses such as foot-and-mouth disease virus; double-stranded DNA non-enveloped viruses such as adenovirus; Alternatively, dsDNA enveloped viruses such as African swine fever virus or Aujeszky's disease virus were used.

Each virus was infected with Vero cell line to obtain a virus bulk, and the virus bulk was mixed with the stabilizer (CVS) prepared in Preparation Example 1 at a volume ratio of 1:1 and used.

Example 1. Comparison of stabilizing effects of stabilizers (CVS) on various viruses

The present inventors analyzed the stabilizing effect of the stabilizer (hereinafter referred to as CVS) composed of the composition of Table 1 on various viruses. The virus viability of the virus mixed with the stabilizing agent was measured by the tissue culture infection dose 50 (TCID ₅₀ ) method. Specifically, Vero-k cells are dispensed and cultured at a concentration of 1.2 X 10 ⁴ cells/well in a 96-well cell culture plate to form a monolayer. Thereafter, the cell culture medium was removed, and the virus was diluted in a decimal step from the stock solution with a-MEM medium supplemented with 5% fetal bovine serum (FBS), and then dispensed into the 96-well cell culture plate at 37°C and 5% The results were determined by checking the cytopathic effect (CPE) pattern while culturing in CO ₂ conditions, and the titer was calculated by the Reed-Muench method.

1-1. Stabilizing effect on single-stranded negative RNA enveloped virus (ss(-)RNA enveloped virus)

Akabane virus K-9 strain was purchased from the National Veterinary Science and Quarantine Service and used. Akabane virus bulk (10 ^6.7 TCID ₅₀ /ml) was mixed with CVS at a volume ratio of 1: 1, stored at 4 ° C or 25 ° C, and the viability of the virus was measured by the TCID ₅₀ method. As a result, as shown in FIG. 1, no significant difference was found between the control group mixed with PBS and the CVS mixed group at 4 ° C., but the viability of the control group at 25 ° C. However, in the CVS mixed group, it was observed that the viability of Akabane virus remained very high even on the 35th day.

In addition, Rabies virus ERAGS strain was purchased and used from the National Veterinary Science and Quarantine Service, and rabies virus bulk (10 ^7.5 TCID ₅₀ /ml) was mixed with CVS at a volume ratio of 1: 1 and then at 4 ° C or 25 ° C. While stored, the viability of the virus was measured through the TCID ₅₀ method. In addition, a comparative control group mixed with 5% (w/v) trehalose, which was conventionally used for virus stabilization, was analyzed together. As a result, as shown in FIG. 2, in the case of rabies virus, significantly better virus viability was confirmed in the experimental group mixed with the stabilizer of the present invention compared to the control group and the comparative control group (trehalose mixed group) at both 4 ° C and 25 ° C conditions.

1-2. Stabilizing effect on single-stranded positive RNA enveloped virus (ss(+)RNA enveloped virus)

In the present invention, Japanese encephalitis virus KV1899 strain was used. Japanese encephalitis virus bulk (10 ^7.25 TCID ₅₀ /ml) was mixed with CVS at a volume ratio of 1: 1, stored at 25 ° C, and the viability of the virus was measured by the TCID ₅₀ method. As a result, as shown in FIG. 3, there was no significant difference in virus viability between the control group and the CVS mixed group until the 4th day, but from the 5th day, the viability of the virus in the control group rapidly decreased.

1-3. Stabilizing effect on single-stranded positive RNA non-enveloped virus (ss(+)RNA non-enveloped virus)

In the present invention, foot-and-mouth disease virus O1 Manisa strain was used. Foot-and-mouth disease virus bulk (10 ^5.7 TCID ₅₀ /ml) was mixed with CVS at a volume ratio of 1: 1, stored at 25 ° C, and viability of the virus was measured by the TCID ₅₀ method. In addition, a comparative control group mixed with 5% (w / v) sucrose, which was used for virus stabilization in the past, was analyzed together. As a result, as shown in FIG. 4, in the case of the control group, the virus viability decreased over time, and it was confirmed that all of the viruses were killed on the 4th day, and in the control group, the sucrose mixed group was observed to kill all viruses on the 7th day. . However, it was found that the experimental group (CVS) in which the stabilizer of the present invention was mixed showed high virus viability even on the 7th day.

1-4. Stabilizing effect on dsDNA non-enveloped virus

In the present invention, recombinant adenovirus (Korea Veterinary Culture Collection accession no. KVCC-VR1500041) was used. After culturing the adenovirus in 293A cells, the cytopathic effect was confirmed, and the virus bulk was obtained and used in the experiment. Adenovirus bulk (10 ^9.0 TCID ₅₀ /ml) was mixed with CVS at a volume ratio of 1: 1, stored at 4 ° C, and the viability of the virus was measured by the TCID ₅₀ method. The 5% (w /v) A control group mixed with trehalose was analyzed together. As a result, as shown in FIG. 5, no significant difference in virus viability was confirmed in all groups until the 20th day, but after the 20th day, it was observed that the virus viability decreased over time in the control group and the trehalose mixed group, and the CVS mixed group showed high virus viability up to 30 days, and decreased virus viability after 30 days, showing an excellent virus stabilization effect compared to the control group and the trehalose mixed group.

1-5. Stabilizing effect on dsDNA enveloped virus

African swine fever virus (ASFV) Yc1-Fc PSV strain was used. After culturing ASFV in Cas-01 cells, the cytopathic effect was confirmed, and virus bulk was obtained and used in the experiment. ASFV bulk (10 ^6.1 TCID ₅₀ /ml) was mixed with CVS at a volume ratio of 1: 1, stored at 25 ° C or 37 ° C, and the viability of the virus was measured by the TCID ₅₀ method. As a result, as shown in FIG. 6, in the control group, virus viability began to decrease over time at both 25 ° C and 37 ° C conditions, and it was observed that all viruses died on day 55, but in the case of the CVS mixed group at 25 ° C. showed high virus viability up to day 83, and it was confirmed that all viruses were killed on day 83 under the condition of 37°C.

In addition, Aujeszky's disease virus YS400 strain cultured in Vero-k cells was used in the experiment, and Aujeszky's disease virus bulk (10 ^6.5 TCID ₅₀ /ml) was mixed with CVS at a volume ratio of 1:1 and then 4 Stored at ° C or 25 ° C, the viability of the virus was measured through the TCID ₅₀ method. As a result, as shown in FIG. 7, in the CVS mixed group at 4° C., no decrease in virus viability was confirmed until day 55. In addition, in the control group at 25 ° C., virus viability decreased over time, and it was observed that all viruses were killed on day 55, but the CVS mixed group showed excellent virus viability compared to the control group.

Through the above results, the stabilizer of the present invention has an excellent effect of stabilizing the virus, which is an immunogen, during storage after preparation of a virus vaccine, and can be usefully used to effectively maintain a prophylactically effective virus titer without loss of infectious titer in a virus vaccine. showed that it could.

Example 2. Analysis of virus stability effect of stabilizer according to freeze-thaw stress

An experiment was conducted to confirm whether the stabilizer (CVS) according to the present invention can improve the stability of the virus in the freeze-thaw step involved in the vaccine manufacturing process. Briefly, after preparing a total of 100 ml by mixing Akabane virus bulk (10 ^6.7 TCID ₅₀ /ml) and a stabilizer at a volume ratio of 1: 1, freeze overnight in a deep freezer at -74 ° C. After that, the process of melting at room temperature (25 ± 2 ℃) for 4 hours was performed as one cycle, and a portion was taken from the sample melted each time and the virus titer was measured by the TCID ₅₀ method.

As a result, when the freeze-thaw process was repeated more than 4 times, the viability of the virus began to decrease in the control group (PBS added), but in the test group to which CVS was added, the viability of the virus decreased even when the freeze-thaw process was repeated 8 times. It was confirmed that this did not happen (FIG. 8).

In addition, as a result of preparing a lyophilized formulation after mixing CVS with the virus bulk at a volume ratio of 1:1 or 1:3, it was confirmed that the stabilizer of the present invention had no effect on the lyophilized formulation. Through the above results, it was found that the stabilizer (CVS) according to the present invention can greatly improve the stability of the virus, which is the immunogen of the vaccine, under freeze-thaw stress conditions.

Claims (8)

Based on 100 parts by weight of glutamic acid, 40 to 60 parts by weight of methionine, 40 to 60 parts by weight of valine, 40 to 60 parts by weight of glutamine, 40 to 60 parts by weight of asparagine , 40 to 60 parts by weight of histidine, 40 to 60 parts by weight of serine, 40 to 60 parts by weight of alanine, 40 to 60 parts by weight of glycine, 40 to 60 parts by weight of threonine , Proline (proline) 40 to 60 parts by weight, arginine (arginine) 40 to 60 parts by weight and aspartic acid (aspartic acid) 40 to 60 parts by weight of a composition for enhancing the stability of viral antigens for animal vaccines. delete delete A vaccine composition comprising the composition for enhancing the stability of a viral antigen for an animal vaccine according to claim 1 and at least one viral antigen. The vaccine composition according to claim 4, wherein the viral antigen is a single-stranded RNA virus or a double-stranded DNA virus. The vaccine composition according to claim 4, further comprising a pharmaceutically acceptable carrier or adjuvant. The vaccine composition according to claim 4, wherein the vaccine composition is a liquid or lyophilized formulation. preparing viral antigens for animal vaccines; and
A method for preparing an animal vaccine with enhanced stability, comprising mixing the prepared viral antigen for animal vaccine with the composition for enhancing the stability of the viral antigen for animal vaccine of claim 1,
The method for preparing an animal vaccine with enhanced stability, characterized in that the viral antigen for the animal vaccine is a single-stranded RNA virus or a double-stranded DNA virus.

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