Peptide - MHC associations

[A. Hatton]

Can anybody explain how a peptide vaccine works? Does it bin to free MHC 
molecules on a cell surface (as I have read)? I'm sure it must work also by 
starightforward phagocytosis by APCs. If this is so, are they degraded or do 
you have to administer them in a form that is degraded into the final 
immunogenic peptide?

Please help, I need this for my dissertation yet I cannot fing any reference 
as to how they are expressed by APC's.

Anthony Hatton

E-mail : bigtone at globalnet.co.uk