  The response of the immune system to different vaccination patterns is
studied with a simple model. It is argued that the history and characteristics
of the pattern defines very different secondary immune responses in the case of
infection. The memory function of the immune response can be set to work in
very different modes depending on the pattern followed during immunizations. It
is argued that the history and pattern of immunizations can be a decisive (and
experimentally accessible) factor to tailor the effectiveness of a specific
vaccine.
