What are Vero cells?
Vero cells are a continuous adherent cell line that is frequently used in cell culture and plays an important role in worldwide vaccine and vector production (manufacturing). Unlike other mammalian cells, they do not secrete interferon alpha or beta when infected by viruses – this is one of the reasons that efficient replication of many viruses can be achieved in Vero cells, leading to high virus titers.
Determination of Vero cells’ Whole Genome Sequence
The ‘Vero’ lineage was isolated from kidney epithelial cells extracted from an African green monkey (Chlorocebus sp.) in 1962 at the Chiba University in Japan (Yasumura, Y. and Kawakita, Y. (1963). Nihon rinsho, 21, 1201-1215). The whole genome sequence of a Vero cell line was determined by Osada in 2014, which indicated that it was derived from a female Chlorocebus sabaeus. In addition, the loss of the type I interferon gene cluster was confirmed by a homozygous ~9-Mb deletion on Chromosome 12 (Osada N., et al, (2014). DNA Research pp. 1–11).
Most Widely Accepted Continuous Cell Line
The Vero cell line is the most widely accepted continuous cell line by regulatory authorities and has been used for the production of vaccines for over 40 years. Examples include vaccines against Polio, Smallpox, Rabies, Japanese Encephalitis, Rotavirus, Influenza, Vaccinia, Ross River, West Nile, Chikungunya, Tick-borne encephalitis virus (TBE), Hepatitis A, and SARS-Coronavirus including SARS CoV-2.
Significant Advantages of Vero Cells
Adherent Vero cells can be grown on surfaces such as cell culture flasks, cell factories, cell stacks, roller bottles, and on micro carriers in stirred tank bioreactors. The largest commercial bioreactor scale that was established for Vero cells so far was 6,000L.
Although many Vero cell banks were generated with the use of serum, Vero cells can be grown in commercial serum-free media. Vero cells provided by Nuvonis have been grown only in serum-free / animal component-free medium, thus providing significant advantages in regulatory terms and in reduced time-to-market vaccine development. Nuvonis provides both R&D cells, and Vero cell banks produced under GMP and tested according to ICH guidelines.