Help with peptide motifs of HLA Classes

[George A. Heavner]

I am interested in scanning several protein sequences to determine if they 
contain known peptide motifs recognized by different HLA molecules.  Can 
anyone tell me if there are programs available that can do this and is there a 
database of identified peptide motifs?  PC-based programs are preferred but 
I have Mac or Unix machines as well.

I appreciate any assistance that you can provide.

George A. Heavner