Biomanufacturing a COVID-19 vector vaccine |ASTRAZENECA

Approaches to vaccine development to prime the body's immune response to COVID-19 include; 

• Using weakened viruses,
• Using viral proteins, 
• Using specific viral genetic code, either DNA or RNA, directly or creating viral vectors with specific viral genetic code. 

A COVID-19 adenoviral vector vaccine is an adenovirus vector based on a common cold that has been modified and inserted with the genetic material for the SARS-COV2 spike protein. 

Production starts with assembly of its genetic code. The adenovirus vector is engineered from adenovirus DNA by removing essential genes to stop it being able to replicate, so it can only act as a carrier and not cause disease. 

Adding the coronavirus spike protein DNA creates the full genetic sequence for the adenoviral vector vaccine. The genetic code is introduced into a producer cell, where it is transcribed and translated to form the COVID-19 adenoviral vector vaccine. 

The human cell line is engineered to contain the missing adenovirus genes so that when the vector vaccine is introduced, it can infect the cells and use the cell machinery and missing viral genes to be able to replicate producing identical copies.

Vaccine molecules are also replicated with the division of the cells and the process continues until the right concentration is reached. 

The addition of a chemical lyses the cells bursting them open and the vector vaccine is harvested ready to be further tested filtered and purified before being filled into vials.