A virus can be weakened or inactivated to stimulate the immunity system. Weakened viruses can still reproduce, but not as fast as natural viruses normally do; that is the main point of creating several vaccines to combat or “inactivate” the viruses and prevent them from moving along with their lifecycles.
Vaccines are made of the same constituents that exist in a virus. When a vaccine is synthesized to weaken a particular virus, it reproduces itself fewer than 20 times, whereas a normal virus can reproduce itself hundreds or even thousands of times. Thus, a vaccine virus does not lead to causing diseases; on the contrary, it produces “memory B cells” when replicating, which protects cells from further infection by viruses of the same type in the future. The weakening vaccines provide cells with an everlasting immunity; however, it cannot be given to people who suffer from weakened immunity systems.
Some other vaccines are made for the purpose of inactivating a virus. This is simply attained through the presence of a chemical that immediately kills the virus. However, several doses of that type of vaccines are needed to combat the virus to ensure everlasting immunity.
However, life is not always that simple. Even vaccines can prove to be inactive when attempting to combat or inactivate viruses because they always change their composition. Once they are exposed to a certain medication, they change their whole structure. Thus, there is a need to keep the industry of vaccines and medications in a constant state of updating and innovation to keep pace with this changing nature of viruses.
Vaccine production is a long series of interrelated stages. The process starts with the generation of the antigen, which is “a substance when introduced into the body stimulates the production of an antibody”. An antigen is usually generated in yeast, bacteria or cell cultures. Recombinant proteins derived from viruses can be generated too; however, they need many modifications including ultrafiltration to inactivate some viruses. Eventually, vaccines are finalized by adding preservatives to allow the use of multi-dose vials and stabilizers to increase the vaccine’s life, or adjuvants to enhance the immunity response of the antigen.
All through, chemical reactions occur: between a virus and a cell, between a vaccine and a certain virus, and in laboratories to acquire those vaccines. This last process is studied and explored by a field of chemistry known as “Medicinal Chemistry”. Medicinal Chemistry is all about the application of chemical research techniques to the synthesis of pharmaceuticals. It is directed towards the innovation and discovery of drugs and their development.
Although viruses cannot be viewed as living organisms in the truest sense, they affect other living organisms leading to their destruction in some cases all because they contain chemical constituents that “react” with those that exist inside the cells of living organisms. Chemistry is, once again, the keyword when we look at phenomena that occur to our bodies and take place all around us in nature.
The original article was published in the PSC Newsletter, Summer 2011 issue.
Cover image: source.