It is widely accepted that vaccination still renains the best answer to ITDst infectious diseases. Recently, vaccine developnent has been greatly facilitated by advances in ITDlecular and cell biology which have laid the foundations of a new generation of vaccines. ' hese are exemplified by submit vaccines produced through gene cloning and synthetic peptides mimicking snall regions of proteins on the outer coat of viruses and capable of eliciting virus neutralizing antibodies. However, submit and peptide vaccines are only weakly or non-inmmogenic in the absence of immunological adjuvants. The...