Veterinary Vaccines
Vaccination aims to mimic the development of naturally acquired immunity by inoculation of non-pathogenic but still immunogenic components of a pathogen, or closely related organisms. The term “vaccine” (Latin “vacca,” meaning cow) was first introduced by Edward Jenner to describe the inoculation (or vaccination) of humans with the cowpox virus to protect them against the related human smallpox virus. This historical milestone illustrates the close relationship between humans and animals’ infectious disease sciences. Vaccination has proven to be the most effective tool to control and prevent diseases and to facilitate the safe trade of live animals. According to Verified Market Research, the global animal vaccine market is estimated to surpass USD 14 billion by 2030.
Benefits of Veterinary Vaccines
The veterinary vaccines sector has grown consistently due to new technological advancements in vaccine development, the continuous development of drug resistance by pathogens and the emergence of new diseases. Apart from improving animal health and productivity, veterinary vaccines have a significant impact on public health through reductions in the use of veterinary pharmaceuticals (e.g., antibiotics) and hormones and consequently their residues in the human food chain.
Due to the lack of broad-spectrum antiviral pharmaceuticals, using vaccination and adhering to hygienic measures to limit exposure are the only means to prevent or control viral infections. Viruses (especially RNA viruses) are highly variable, and many viral infections are due to viruses with multiple serotypes e.g., foot and mouth disease virus (FMDV) or influenza viruses.
Veterinary Vaccines Production in Cell Lines
A large number of veterinary vaccines is still produced in embryonated chicken eggs or primary chicken embryo fibroblasts. Although primary avian tissue for virus replication is provided by specific pathogen-free (SPF) production plants, sterility during vaccine manufacturing on embryonated eggs is difficult to guarantee, and the constant risk of contamination requires the addition of antibiotics.
Thus, continuous avian cell lines have become a modern option for veterinary vaccines’ manufacturing and will definitely replace egg and primary fibroblast technology, as the use of continuous cell lines is cost-effective and reliable.
Multiple cell lines are currently used for viral productions such as Vero, MDCK, MRC5, BHK, CHO or avian cells. Viruses replicating in these cell lines are used for generation of vaccines against many diseases.
Replicated Viruses can Be Used against the Following Diseases
· Marek’s disease,
· Infectious bursal disease,
· Derzsy’s disease,
· Avian influenza
· etc.
Production processes are virus specific and require the development of unique conditions for replication in development and large-scale production.
Suspension and Microcarrier Production Using Nuvonis' Avian Cell Lines
Nuvonis has developed a novel avian (quail) cell line substrate for the manufacturing of a variety of veterinary vaccines. Importantly, the Nuvonis quail cell line is available for growth in suspension (CCX.E10) and for anchorage dependent growth (CCX.2C4), therefore supporting both suspension and microcarrier technologies. Providing suspension and anchorage-dependent avian cell lines, gives developers and manufacturers more flexibility regarding the choice of production system. Available (large-scale) infrastructure, stainless steel or single use systems can be utilized without significant new investments. The classical Cytodex® (Cytiva) microcarrier technology, with a proven track record as well as recent carrier developments in high density systems (e.g., the TIDE® system promoted by ESCO), offer a wide range of process options. The use of an avian suspension cell line allows to quickly scale-up in single use bioreactors at a large volume (> 500L).
Due to the fact that media formulations for both suspension and anchorage dependent Nuvonis avian cell lines are animal component-free, this can result in production cost reduction and a simplified regulatory submission process.
Summary
Veterinary vaccines are important factors of maintaining animal health in a steadily growing market. Novel production technologies, such as the use of state-of-the-art continuous cell lines can lead to significant improvements in manufacturing processes for animal vaccines, in terms of efficiency, quality and production costs. Novel serum free cultured cells such as the quail CCX cell lines developed by Nuvonis allow for flexible and large-scale animal vaccine production, and support both suspension and anchorage-dependent (microcarrier technologies) production systems.