In gemonics era:vaccinology has been overturned in reverse!!
Posted by: Samar Kabeel in Bioinformatics, ImmunologyFor many decades, conventional vaccinology has faced many obstacles. One major problem is that among several antigens of the microbe, you have to identify the most immunogenic (and thus protective) antigens (such as virulent factors, toxins, surface-associated proteins, etc.) suitable for vaccine development. This process is very fastidious and costs a lot as it relies mainly on traditional biochemical and microbiological methods. As a summary, it is carried out as following:
- Firstly, you have to cultivate the microbe and harvest proteins.
- Then you have to identify the antigens one by one.
- After that you can pass to vaccine development stage.
Introducing genomics has greatly contributed to providing a new impulse to vaccinology field. The major role it plays is in the antigen discovery stage. As the genome sequence of many microbes has been identified, the integration between the sequence, proteomics and microarray has introduced what is called “reverse vaccinology” . Reverse vaccinology (RV) means to identify and characterise the antigen using bioinformatics. In RV, you start from the genome and not from the pathogen itself i.e. you start from the opposite direction, that’s why it is called “reverse”.
RV will provide solutions to some problems that usually come up during vaccine development as:
- It will provide fast access to almost all antigens including:less common antigens and antigens not expressed in vitro.
- It represents a new approach for non culturable microorganisms.
On the other hand, the major disadvantage of RV is that it cannot be applied to non-proteinaceous antigens such as lipopolysaccharides and glycolipids.
Tags: GBS, genomics, reverse vaccinology, vaccinology
This topic is very very interesting and its methodology as well.
After the representation of the proteome, digestion into peptides, separation of peptides using HPLC; there’s mass spectroscopy then sequencing, finally comparing the resulting sequences with protein db. They also compare the gene expression (proteome) in vivo vs in vitro. They also compare the synthetic protein with the native protein collected from site of infection for example.
In 2000, there was a paper talking about the possible applications of RV, like for Malaria/ HCV/ TB/ Syphilis. In 2003, the list kept growing by adding S. aureus/ B. anthracis/ Streptococcus pneumoniae/ Chlamydia.
Really great hope 🙂
So in the vaccine development stage, these antigens are tested one by one in order to determine which is crucial for the surival of the mo within the host?? or is there a certain method by which some of these antigens are excluded from the possibility of becoming a future vaccination?
It’s really very interesting issue !!
but I think it’s not important in the antign selection to be crucial for the MO itself..
It may be the antigen that the host cell can recognize the most .. and develop the required antibodies for it
U r totally right, Omnia
in vaccinology, we select the most “immunogenic” antigen which means it is the one which elicit the immune response needed to give protection against this mo. this is the real impact in RV where selecting antigen is not any more fastidious.