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In the early development of vaccines, there were some predominated mechanisms of production. The technological advance has enabled the introduction of much more innovative and safer techniques.

ACELLULAR

A combination of purified subcellular components of the pathogen. They usually have proteins and it may have toxoids.

RECOMBINANT ANTIGEN

Using genetic engineering technology (recombinant DNA), a gene that encodes an antigen is inserted (a protein of a pathogenic microorganism) in a bacteria or yeast. The goal is to produce large amounts of the antigen protein for its subsequent purification and use.

CONJUGATE

In this type of vaccines, cell wall polysaccharides or pathogenic bacteria capsule are combined with proteins of the same pathogen. In this way, the vaccine develops an immune response against several antigens of the bacteria.

INACTIVE

Pathogenic microorganisms are treated with chemical products or heat. This type of vaccines activates the immune system, but it is not able to reproduce in the host. In this way, the immunity is milder and shorter, that is why more doses are needed. In fact, because of the milder immune response of these vaccines, substances called adjuvants are used to increase the immune response of the organism.