Recombinant Type 3 Vaccine Technology
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RECOMBINANT TYPE 3 VACCINE TECHNOLOGY RECOMBITEK KC2 is manufactured by Boehringer Ingelheim. All other RECOMBITEK vaccines are manufactured by Merial. Merial is now part of Boehringer Ingelheim. RECOMBITEK® and PUREVAX® are registered trademarks of Merial. ©2018 Merial, Inc., Duluth, GA. All rights reserved. PET-0510-BIO0618. VACCINE TECHNOLOGY TRADITIONAL VACCINE TECHNOLOGY • Vaccines were originally developed on an empirical basis, • A vector virus is a live virus that carries its own natural relying mostly on attenuation of pathogens (e.g., modified genes, plus the foreign immunity gene(s) of one or more live viral vaccines) or inactivation of pathogens (e.g., different virus(es). killed vaccines). • The vector virus used in RECOMBITEK® and PUREVAX® Type • Many current vaccines owe their success to their ability 3 Recombinant vaccines is a canarypox virus. to target pathogens that have low antigenic variability • Canarypox-vectored recombinant vaccines contain only and for which protection depends on antibody- a portion of the genetic material of a pathogen, not the mediated immunity. complete organism. Therefore, it is not possible for the • On the other hand, important cell-mediated immunity recombined canarypox to produce disease from the against intracellular pathogens is more difficult to obtain pathogen in the vaccinated animal. using inactivated pathogens as vaccines. • Live attenuated pathogen vaccines can elicit cell-mediated WHY CANARYPOX VIRUS? immunity, but may pose potential risks that cannot • Canarypox viruses have specific cytoplasmic requirements be overlooked. Although not often, these vaccines can for replication, which are not met by mammalian be virulent in susceptible hosts or experience reversal cytoplasm, therefore replication cannot occur in of attenuation. mammalian cells. • Canarypox virus is genetically stable, and its large genome WHY RECOMBINANT VACCINE TECHNOLOGY? allows the insertion of single or multiple segments of DNA • Advances in immunology, molecular biology, biochemistry, from the disease-causing organism. and genomics have provided additional perspectives to the vaccinology field. THE BENEFITS OF A CANARYPOX-VECTORED VACCINE • The use of recombinant proteins allows the targeting • Simulates natural exposure and produces both humoral of immune responses focused against a few protective and cell-mediated immunity1,2 antigens, rather than the entire organism. • No risk of reversion to virulence (as the vaccine only • Therefore vaccines can be developed that contain only the contains one or two pieces of DNA from the pathogenic necessary immunogenic protein(s) rather than the entire organism; not the entire organism) virus or bacteria. • Adjuvant-free • Only uses the necessary proteins needed for protection, WHAT IS RECOMBINANT TYPE 3 VACCINE TECHNOLOGY? rather than the entire pathogenic virus • Recombinant Type 3 vaccine technology is based on the ability to isolate and splice (i.e., recombine) gene-sized fragments of RNA or DNA from one organism, for incorporation into a vector virus. 1 Paillot R, Kydd JH, Sindle T et al. Antibody and IFN-gamma responses induced by a 2 Poulet H, Minke J, Pardo MC, Juillard V, Nordgren B, Audonnet JC. Development and recombinant canarypox vaccine and challenge infection with equine influenza virus. registration of recombinant veterinary vaccines. The example of the canarypox vector Veterinary Immunology and immunopathology. 2006;112:225-233. platform. Vaccine. 2006;25:5606-5612. PUREVAX® Rabies: The Manufacturing Process and Mode Of Action STEP 1 RNA Encoding The RNA is reverse transcribed into Glycoprotein G cDNA (a DNA copy of RNA). Glycoprotein G cDNA for Glycoprotein G Canarypox virus has a large enough genome to accommodate extra nuclear material. STEP 3 Rabies rRabies virus master seed is propagated in chick embryo fi broblast cell culture to produce vaccine virus. STEP 2 Using an in vitro procedure, cDNA is inserted into the genome of the canarypox virus making rRabies virus master seed. As the virus attempts to replicate in the Virus enters host cell. cell, the viral DNA is It attempts to replicate transcribed, causing STEP 4 Virus is (but cannot). the production of rRabies vaccine virus is given as a Glycoprotein G. used to manufacture vaccine to PUREVAX vaccine. the animal. Macrophage takes up Glycoprotein G, and presents to lymphocytes. Animal develops both cell-mediated and humoral immune responses and is now protected against rabies infection. Glycoprotein G is expressed on the host cell surface. PUREVAX® FeLV: The Manufacturing Process and Mode of Action STEP 1 The RNA is reverse transcribed into cDNA (a DNA copy of RNA). RNA Encoding RNA Encoding “gag” Protein “env” Protein cDNA for “env” Protein and “gag” Protein Canarypox virus has a large enough genome to accommodate STEP 3 extra nuclear material. rFeLV master seed is propagated in chick embryo fi broblast cell “gag” Protein culture to produce vaccine virus. “env” Protein FeLV STEP 2 Using an in vitro procedure, cDNA is inserted into the genome of the canarypox virus making rFeLV master seed. As the virus attempts to Virus enters host cell. replicate in the cell, the It attempts to replicate viral DNA is transcribed, causing the production of STEP 4 (but cannot). Virus is “env” and “gag” proteins. rFeLV virus is used given as a to manufacture vaccine to PUREVAX vaccine. the animal. Macrophage takes up “gag” and “env” proteins, and presents to lymphocytes. Animal develops both cell-mediated and humoral immune responses and is now “gag” and “env” protected against FeLV infection. proteins are expressed on the host cell surface. RECOMBITEK® Distemper: The Manufacturing Process and Mode of Action STEP 1 RNA Encoding HA The RNA is reverse transcribed (Hemagglutinin) into cDNA (a DNA copy of RNA). Protein RNA Encoding F (fusion) Protein Canarypox virus has a large cDNA for F enough genome to accommodate & HA Proteins extra nuclear material. F (fusion) Protein HA Protein STEP 3 rDistemper virus master seed is propagated in chick embryo STEP 2 Canine Distemper fi broblast cell culture to produce Using an in vitro procedure, vaccine virus. cDNA is inserted into the genome of the canarypox virus making rDistemper virus master seed. As the virus attempts to replicate in the cell, the viral DNA is transcribed, causing the production of HA & F Proteins. Virus enters host cell. STEP 4 It attempts to replicate rDistemper vaccine virus (but cannot). is used to manufacture RECOMBITEK vaccine. Virus is given as a Macrophage takes up HA & F Proteins are vaccine to the animal. HA & F Proteins, and expressed on the host presents to lymphocytes. cell surface. Animal develops both cell-mediated and humoral immune responses and is now protected against distemper infection..