KR-102963232-B1 - Novel Corynebacterium pseudotuberculosis strain isolated from caseous lymphadenitis infected goat and vaccine composition for preventing caseous lymphadenitis comprising the same

Abstract

The present invention relates to a novel strain of Corynebacterium pseudotuberculousis and a vaccine composition containing the same, and more specifically, to a novel strain of Corynebacterium pseudotuberculousis isolated from an abscess of a domestic goat with caseous lymphadenitis and exhibiting excellent immunogenicity, and a vaccine composition for the prevention of caseous lymphadenitis containing an attenuated or inactivated strain thereof. The novel strain of C. pseudotuberculosis according to the present invention exhibits excellent immunogenicity and can provide an excellent preventive effect against caseous lymphadenitis caused by C. pseudotuberculosis infection.

Inventors

• 조호성
• 탁동섭
• 오연수
• 김정한
• 서병주
• 이소민
• 강재구

Assignees

• 전북대학교산학협력단
• 강원대학교산학협력단
• 우진비앤지 주식회사

Dates

Publication Date

20260512

Application Date

20230509

Claims (13)

1. A novel Corynebacterium pseudotuberculosis WGB-Cory-1 strain isolated from an abscess of a goat with caseous lymphadenitis and deposited under accession number KCTC 15379BP.
2. delete
3. A vaccine composition for the prevention of caseous lymphadenitis comprising the Corynebacterium pseudotuberculosis WGB-Cory-1 strain (accession number KCTC 15379BP).
4. A vaccine composition according to paragraph 3, characterized in that the strain is attenuated or inactivated.
5. A vaccine composition according to claim 3, characterized in that the bacterial count content in the vaccine composition is 10⁴ to 10⁹ cfu.
6. A vaccine composition according to paragraph 3, characterized in that the vaccine composition further comprises a veterinary acceptable adjuvant, carrier, or combination thereof.
7. A vaccine composition according to paragraph 3, characterized in that the vaccine composition is for small ruminants.
8. A vaccine composition according to claim 7, characterized in that the small ruminant is a sheep or a goat.
9. A method for preventing caseous lymphadenitis comprising the step of administering a vaccine composition according to any one of claims 3 to 8 to an animal other than a human.
10. A method according to claim 9, characterized in that the animal is a small ruminant.
11. A method according to claim 10, characterized in that the small ruminant is a sheep or a goat.
12. (a) a step of culturing a novel Corynebacterium pseudotuberculosis WGB-Cory-1 strain deposited under accession number KCTC 15379BP; and (b) a step of inactivating or attenuating the strain, comprising a method for preparing a vaccine composition.
13. A manufacturing method according to claim 12, characterized in that the inactivation is achieved by formalin treatment or heat treatment.

Description

Novel Corynebacterium pseudotuberculosis strain isolated from caseous lymphadenitis infected goat and vaccine composition for preventing caseous lymphadenitis comprising the same The present invention relates to a novel strain of Corynebacterium pseudotuberculousis and a vaccine composition containing the same, and more specifically, to a novel strain of Corynebacterium pseudotuberculousis isolated from an abscess of a domestic goat with caseous lymphadenitis and exhibiting excellent immunogenicity, and a vaccine composition for the prevention of caseous lymphadenitis containing an attenuated or inactivated strain thereof. Caseous lymphadenitis is a chronic infectious disease that infects lymph nodes and other areas, and is widespread in countries around the world that raise goats and sheep. The causative agent is Corynebacterium pseudotuberculosis , which causes lesions similar to tuberculosis, so it is also called 'pseudotuberculosis'. This bacterium is a zoonotic pathogen that appears as an occupational disease among farm and slaughterhouse workers in the form of localized suppurative granulomatous lymphadenitis, and human infection can also occur from the consumption of unpasteurized goat milk. The lesions manifest as external, internal, or mixed types. The external type, which primarily forms abscesses in superficial lymph nodes such as those under the jaw and behind the ears, spreads the disease to other animals by contaminating the barn floor with bacteria through the rupture of the abscess. In contrast, the internal type, which forms abscesses in internal lymph nodes and the lungs, has a lower incidence than the external type but progresses to a chronic state, resulting in more severe symptoms. Infection manifests as weakness, weight loss, and reduced milk production. Since it mostly occurs in clusters, it is a disease that causes significant economic damage to farms due to reduced productivity. As a result of antibody testing for caseous lymphadenitis conducted by the Animal and Plant Quarantine Agency on approximately 40 goat farms nationwide, a high prevalence rate of over 57% was observed. In Australia, where the incidence of caseous lymphadenitis is known to be high, the prevalence rate was over 50% prior to the use of vaccines in the 1980s, but it was found to have decreased significantly to around 20% after the introduction of vaccines. However, there is currently no fully commercialized vaccine available. Currently, there is no commercially available vaccine in Korea, and since antibiotics cannot completely eradicate the causative agent in the event of infection, infected animals must be culled as soon as possible, isolated from healthy animals, and barns disinfected. Therefore, to address the decline in farm productivity and the risk of human infection, it is absolutely necessary to conduct active surveys to assess the current situation and to develop a vaccine using domestic isolates. Figure 1 shows the results of a comparative analysis of clinical symptoms for each animal group in an embodiment of the present invention. Figure 2 shows the antibody analysis results for each animal group in an embodiment of the present invention. Figure 3 is the result of observing the histopathology of lymph nodes isolated from each animal group after the completion of the challenge inoculation experiment in an embodiment of the present invention. Figures 4a and 4b show the phylogenetic tree of C. pseudotuberculosis isolated in an embodiment of the present invention. The present invention will be explained in detail below through the following examples. However, the following examples are merely illustrative of the present invention and do not limit the present invention. Example 1: Isolation and Identification of C. pseudotuberculosis Strain To identify the cause of disease in goats exhibiting symptoms of caseous lymphadenitis from domestic goat farms from February to April 2020, abscesses collected from goats were cultured on sheep blood medium to isolate pure colonies exhibiting hemolysis. Bacterial colonies were enriched and cultured on Brain Heart Infusion (BHI) medium containing 0.5% Tween 80 (0.5% Tween 80® + BHI), and pure bacterial colonies were isolated from BHI agar medium. Polymerase Chain Reaction (PCR), Multilocus Sequence Typing (MLST), and pathogenicity genes (18 types) were tested on the pure bacterial colonies, and they were identified as C. pseudotuberculosis , the causative agent of goat caseous lymphadenitis (Fig. 4). The molecular biological characteristics of C. pseudotuberculosis, a causative agent of caseous lymphadenitis isolated from domestic goat farms, were analyzed and found to be mostly similar. However, the isolate selected as a vaccine candidate was chosen because it exhibited superior proliferation compared to other domestic isolates, making mass production easier, and its genetic lineage was included within a range that could encompass strains isolated from both domestic