Fig. 7.

Representation of proteins in the HLA ligandome. A, this figure depicts the number of proteins as a function of the number of peptides identified per protein. HLA ligands derived from 7059 unique proteins are in our dataset. In our dataset, about 50% of the proteins are represented by one peptide, 20% are represented by two peptides, 10% are represented by three peptides, and so on. As can be seen, there is a gradual decrease in the number of peptides by which a protein is represented. Up to 41 peptides/protein are present in our dataset. B, the protein length is depicted as a function of the number of peptides by which the protein is represented in HLA. The number of peptides in HLA of a protein correlates well with its protein mass.