Voie d'immunisation et séquence d'administration de l ... - TEL

tel-00827710, version 1 - 29 May 2013
Table 5. Comparison of different forms of antigen for vaccine purposes. E, endocytosis; P,
phagocytosis.
2) Nucleic acid-based vaccines
DNA or RNA have also been tested as antigen for eliciting anti-tumor and anti-viral
responses. Injection of nucleic acids should work at two levels: first, these components
encode for a specific antigen, but they can also act as ligands for PRRs resulting in the
additional induction of an inflammatory response.
DNA vaccines consist of bacterial plasmids in which specific sequences encoding antigens
have been inserted. They are injected intramuscularly or intradermally where the DNA will be
taken up and antigen will be expressed in transfected cells. In most cases, the transfected
cells are not APCs and have to be phagocytosed by DCs, allowing cross-presentation on
MHC-I molecules. Alternatively, DCs may be directly transfected inducing direct antigen
presentation (Rice et al., 2008). Interestingly, other sequences such as leader sequences that
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