Modified Marek's disease virus, and vaccines made therefrom

Patent metadata

Field	Value
Publication number	US-11510978-B2
Application number	US-201916262774-A
Country	US
Kind code	B2
Filing date	Jan 30, 2019
Priority date	Mar 22, 2012
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

The present invention provides an effective vaccine for Marek's disease, which may be prepared using a recombinant Marek's Disease Virus (MDV), strain CVI988, having been transformed with a foreign DNA construct that includes a long terminal repeat sequence of a reticuloendotheliosis virus. This safe viral agent elicits a highly protective immune response in a chicken against virulent MDV challenge without causing a significant degree of pathogenicity. Suitable formulations of the vaccine for use in chickens include an effective immunization dosage of this novel viral agent, along with a pharmaceutically acceptable carrier or diluent.

First claim

What is claimed is:

1. A method of eliciting a protective immune response against Marek's Disease virus (MDV) in an avian, comprising:
administering to the avian a vaccine,
said vaccine comprising a veterinarily or pharmaceutically acceptable carrier or diluent and an effective immunization dosage of a MDV viral agent stably transformed with a foreign DNA construct, comprising a long terminal repeat (LTR) sequence of a reticuloendotheliosis virus,

wherein the MDV viral agent is a clonal virus, and not a mixed population of parental and recombinant virus,
wherein the MDV viral agent is a CVI988/X MDV SR-1 RN1250 deposited at ATCC under the accession number PTA-122066 and contains at least 200 plaque forming units per dose per avian, and
wherein the vaccinated avian has a prevented fraction rate of 0.84 or greater when challenged with vvMDV RB1B virus.

2. The method of claim 1 , wherein the avian is a chicken.

3. The method of claim 1 , wherein the vaccine does not cause a significant degree of pathogenicity in the avian when administered.

4. A vaccine for eliciting a protective immune response against MDV in an avian, comprising:
a veterinarily or pharmaceutically acceptable carrier or diluent for subcutaneous administration and
an effective immunization dosage of a MDV viral agent stably transformed with a foreign DNA construct, comprising a long terminal repeat (LTR) sequence of a reticuloendotheliosis virus,
wherein the viral agent is a clonal virus, and not a mixed population of parental and recombinant virus,
wherein the MDV viral agent is a CVI988/X MDV SR-1 RN1250 deposited at ATCC under the accession number PTA-122066
wherein the MDV viral agent in the vaccine is present in an amount of at least 200 pfu per dose per avian, and
wherein an avian vaccinated with the vaccine has a prevented fraction rate of 0.84 or greater when challenged with vvMDV RB1B virus.

5. The vaccine of claim 4 , in a dosage form having a volume between 0.1 mL to 2.0 mL.

6. The method of claim 1 , wherein the avian is administered between 0.1 mL to 2.0 mL of the vaccine.

7. The method of claim 1 wherein the LTR has the sequence of SEQ ID NO:2 and the LTR sequence comprises a Pac I excised DNA segment from an MDV having all the identifying characteristics of the strain deposited at ATCC under accession number PTA-4945 and wherein the LTR sequence is inserted 5′ of the ICP4 gene of the MDV.

8. The vaccine of claim 4 , wherein the LTR has the sequence of SEQ ID NO:2 and the LTR sequence comprises a Pac I excised DNA segment from an MDV having all the identifying characteristics of the strain deposited at ATCC under accession number PTA-4945 and wherein the LTR sequence is inserted 5′ of the ICP4 gene of the MDV.

Assignees

• Boehringer Ingelheim Animal Health Usa Inc

Inventors

• Pritchard Joyce
• Mebatsion Teshome
• Bublot Michel

Classifications

• A61K39/12

  Viral antigens · CPC title

• A61P31/12

  Antivirals · CPC title

• A61P37/00

  Drugs for immunological or allergic disorders · CPC title

• A61K2039/552

  Veterinary vaccine · CPC title

• A61K39/255 Primary

  Marek's disease virus · CPC title