Gritstone showcases mass spec-based neoantigen discovery platform

Gritstone Oncology Inc. (NASDAQ:GRTS) unveiled the inner workings of its mass spectrometry-based neoantigen identification platform, EDGE, in a Nature Biotechnology study published Monday. Results from the paper suggest building a machine-learning algorithm based on human leukocyte antigen (HLA)-bound peptides identified via mass spectrometry, rather than HLA-peptide binding affinities, could improve the accuracy of predicting HLA-presented peptides on tumor cells by up to ninefold.

Common methods to identify neoantigens include finding candidate antigens by comparing tumor and healthy cell DNA or RNA to identify mutations or alternative splicing events unique to cancer cells, and then determining how strongly the corresponding candidate peptides bind an HLA. High peptide-HLA affinity could indicate a neoantigen that will be presented by the HLA and lead to an antitumor immune response (see "Neo Wave" & "Alt-neoantigens")...