Most Important Discoveries in Vaccinology Part II

Polysaccharides, Bacterial polysaccharide

The way this will open the pre World War II, but the operation the immunological effect of the combination of bacterial polysaccharide with proteins has happened only recently. The 80’s saw the implementation of this technology coma Hib vaccine as a first conjugate being licensed for infants in 1990;

A reminder is not necessary for the spectacular success of the Hib vaccine, which promises eradicate the disease and perhaps also the body.
It seems that the spectacular success also attend the conjugate vaccine
pneumococcus.

Invasive disease with bacteremia caused by serotypes in the vaccine is likely to be prevented almost completely. The localized disease as meningitis and pericarditis should also disappear.

In addition, the test of the vaccine showed high efficacy against pneumonia with consolidation the X-rays, suggesting that pneumococcal pneumonia is more common in children suspected.

The application of the vaccine in the developing world could thus have major consequences on mortality, while the application in the world developed could reduce the problem of antibiotic resistant peneumococo. However, the effect of vaccination on the epidemiology of pneumococcal serotypes and substitution by non-vaccine serotypes will have to be observed carefully.

The meningococcal polysaccharide conjugated to proteins are still in early, but the results in conjunction with the Group C in the United Kingdom has suggested that a large proportion of meningococcal meningitis and fulminant disease can be prevented.

GENETIC ENGINEERING

No doubt historians genetic engineering as one of the discoveries of the twentieth century. For vaccinology, this discovery means that someone isolate the encoding for a protective antigen protein, one gene can be inserted into cells of bacteria, yeast or animal origin, which then produce the protein in large quantities. The most important result of this discovery so far is recombinant yeast that produces the surface antigen for hepatitis B, but the same technique has already produced in bacteria antigens for vaccines against the disease Lyme disease, pertussis and cholera.


VECTOR ATTENUATOR

In the 80s, the researchers determined that certain organisms attenuated naturally or artificially could carry the genetic information of pathogens and that during replication in an animal, they could transcribe, translate and present such information to the host’s immune system. Thus, the field of vetorologia born. Among the bacteria, the vectors are the most popular Bacillus Calmette-Guerim (BCG) and attenuated salmonella, while among the viruses, the attention has turned to the pox virus, adenovirus and alphavirus, although other agents such as herpes simplex virus, adeno associated with them, and even retroviruses, have their defenders.

The study of vectors has raised the concept of first rib. This is because although vector antigens themselves are rarely given an answer sufficient B cells, inoculation serial vector vaccine followed by protein 5 or plasmid DNA is induced, respectively, strong responses of T and B cell Replicas of alphavirus and poxvirus serve as illustration. Poxviruses include vaccinia mutants, such as MVA and NYVAC, as well as attenuated poxvirus animals naturally.

The recombinant preparations are recombination events that occur together in cells infected with viruses and cross-infected with the gene of interest. The Canarypox is an example of a virus that replicates only in human abortion. As regards the production of antibody, the ability of poxvirus vectors to prepare for the antibody response has been demonstrated by recombinant canarypox HIV envelope, while the ability of poxviruses to stimulate strong cellular immunity has been demonstrated by the canarypox-CMV.

The alphaviruses as vectors depend on the ability to insert foreign genes in the genome, which are reflected in pseudovirions produced during replication abortion. The genome of the alphavirus structural genes do not contain required for replication and structural genes.

If the structural genes are replaced by foreign genes, pseudo-replication can be induced by auxiliary builders containing the structural genes but incapable of making viral RNA. The structural proteins will accumulate together with foreign proteins.

TRANSGENIC PLANTS AND PLANT VIRUSES

The use of fruit or vegetables administered oral vaccine containing antigens could also be considered an example of vetoriação. However, the idea of distributing vaccines in the food chain is sufficiently different to give it its own place.

There are two ways to make vaccines in plants: the plants transgenic for the genes coding for proteins of vaccine virus or chimeric plants containing the same genes. Clinical trials have shown responses to a variety of antigens produced in plants, including labile toxin from Escherichia coli surface antigens of hepatitis V and glycoprotein vaccine.

Developments in the fields continue to be promising and have already started to change ideas about the immunology of the gastrointestinal tract. If it can be figured out how to stimulate immunity to the antigens of pathogens without breaking the tolerance against the antigens of food, plants or recombinant plant virus may become strategies of effective vaccines.

This will require considerable immune attack, but my great hope for the new century is that immunologists will make more contributions to vaccinology. We know little about the mechanisms of antigenic domain, processing, interference, preparation and many other aspects of immune stimulation that could be used.

DNA UNPROTECT

Unprotected DNA is a term of specialized language for foreign genetic information inserted into a bacterial plasmid that is expressed in the skin or injection into muscle of the host.

The antigen is produced in the muscle cell, but the antigen must be processed in bone marrow cells to achieve an immune response. In animals, magnificent responses have been generated after intramuscular injection of gen, but the results in humans have so far been somewhat disappointing when the DNA is used alone.

If a DNA vaccine will be licensed depends on the response to several questions:

1. Intradermal administration or transcutaneous DNA result in a good answer antibody in humans?

2. An adjuvant is found to reduce the amount of DNA needed to get the answer?

3. The combination of prime rib of DNA with other forms of vaccination will full immune response, ie, strong cellular responses and antibody when necessary?

The answers to these questions are likely to come early studies of vaccines against HIV and malaria. Even if the DNA ever achieve the status of a vaccine for a particular infection, already has had tremendous value as a tool for the identification of antigens
guards. The more pathogens are sequenced, their genes may be identified and tested for protection in animal models.

This will simplify the selection of protective antigens that could have escaped the attention otherwise. This strategy has already proved useful for the development of vaccines against experimental meningococcal group B and Chlamydia pneumoniae.