Recombinant vaccine : Most developing technique in biotechnology
Tags: Biotechnology, Recombinant Vaccine, Microbiology, Vaccines, Bioengineering

Recombinant vaccine : Most developing technique in biotechnology

Now a days recombinant vaccine is being more interest for scientists because it is very effective to treat diseases. Truptikalathiya Nov 26, 2020·3 min read

Genetically modified microorganisms may play a significant role in combating human diseases by production of recombinant vaccine.

The antigenic material present in a vaccine that elicits an immune response is normally an inactivated form of the infectious agent. For example, antiviral vaccines often consist of virus particles that have been attenuated by heating or a similar treatment. In past, two problems have hindered the preparation of attenuated viral vaccines: (i) The inactivation process must be 100% efficient, as the presence in a vaccine of just one live particle can result in infection; and (ii) The large amount of virus particles needed for vaccine production are usually obtained from tissue culture and unfortunately some viruses, like hepatitis B virus, do not grow in tissue culture. Thus to avoid these problems, the concept of recombinant vaccines came into exist. It is belive that these recombinant vaccines would be free of intact virus particles and could be obtained in large quantities.

The use of gene cloning in the field of vaccine preparation on the discovery that virus specific antibodies are sometimes synthesized in response not only the whole virus particle, but also to isolated compounds of the virus. This is used for preparation of purified proteins present in the virus coat. Thus if the genes encoding antigenic proteins of a particular virus could be identified and inserted into an expression vector, recombinant vaccines could be produced using gene cloning procedures.

Unfortunately, this approach has not been entirely successful, because recombinant coat proteins often lack the full antigenic properties of the intact virus. The notable success has been with hepatitis B virus, whose coat proteins has been synthesized in saccharomyces cerevisiae, using a vector based plasmid. The protein was obtained in reasonably high quantities and when injected into monkeys, it provided protection against hepatitis B. This recombinant vaccine has been approved for use in humans.

Another way is that of using recombinant vaccinia viruses as live vaccines against small pox and other diseases. Thus, if a gene coding for a virus coat protein, for example, the hepatitis B major surface antigen, is ligated into the vaccinia genome under the control of a vaccinia promoter, then the gene will be expressed. After injection into the bloodstream replication of the recombinant virus result not only in new vaccinia particle, but also significant quantities of the major surface antigen. Immunity against both smallpox and hepatitis B would result.

The possibility of broad-spectrum vaccines is raised by the demonstration that a single recombinant vaccinia, expressing the genes for influenza virus haemagglutinin, hepatitis B major surface antigen, and herpes simplex virus glycoprotein, confers immunity against respective disease in monkey.

Some of the recombinant vaccines under development include recombinant anthrax vaccine, recombinant HIV vaccine, and recombinant cholera vaccine.