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 POLYSACCHARIDES

External wall lipopolysaccharides or pathogen bacteria capsules are used to generate an immune response or recognition of the external part of the microorganism.

TOXOIDS

They are inactivated toxic components of pathogenic microorganisms.

DNA VACCINE

This type of vaccine contains the DNA of a pathogen that encodes antigenic proteins. One advantage of DNA vaccines is that they can be easily produced and stored, while the main problem is that it is not possible to know for certain if this DNA can integrate into a chromosome in the cells or cause mutations in the genome of the patient that receives the vaccine.

RECOMBINANT VECTOR

In this type of vaccines, it is administered an attenuated or nonpathogenic microorganism carrying DNA that encodes an antigen of the pathogenic microorganism. The most often microorganisms used in this type of vaccines are vaccinia virus, some nonpathogenic lactic acid bacteria and attenuated variants of M. tuberculosis and Salmonella Typhi. The main problem with this type of vaccines is the insufficient immune response.

LIVE ATTENUATED

These vaccines contain microorganisms cultivated under controlled conditions where they lost or attenuated their pathogenic properties. They develop longer immune response and are commonly used in adults. 25