Strategies for maximizing the potency and specificity of cancer immunotherapies have sparked efforts to identify recurrent epitopes presented in the context of defined tumor-associated neoantigens. Discovering these neoepitopes can be difficult owing to the limited number of peptides that arise from a single point mutation, a low number of copies presented on the cell surface, and variable binding specificity of the human leukocyte antigen (HLA) class I complex. Due to these limitations, many discovery efforts focus on identifying neoepitopes from a small number of cancer neoantigens in the context of few HLA alleles. Here we describe a systematic workflow to characterize binding and presentation of neoepitopes derived from 47 shared cancer neoantigens in the context of 15 HLA alleles. Through the development of a high-throughput neoepitope-HLA binding assay, we surveyed 24,149 candidate neoepitope-HLA combinations resulting in 587 stable complexes. These data were supplemented by computational prediction that identified an additional 257 neoepitope-HLA pairs, resulting in a total of 844 unique combinations. We used these results to build sensitive targeted mass spectrometry assays to validate neoepitope presentation on a panel of HLA-I monoallelic cell lines engineered to express neoantigens of interest as a single polypeptide. Altogether, our analyses detected 84 unique neoepitope-HLA pairs derived from 37 shared cancer neoantigens and presented across 12 HLA alleles. We subsequently identified multiple TCRs which specifically recognized two of these neoantigen-HLA combinations. Finally, these novel TCRs were utilized to elicit a T cell response suggesting that these neoepitopes are likely to be immunogenic. Together these data represent a validated, extensive resource of therapeutically relevant neoepitopes and the HLA context in which they can be targeted.
[doi:10.25345/C5NS0M28J]
[dataset license: CC0 1.0 Universal (CC0 1.0)]
Keywords: HLA ; Immunopeptidomics ; Shared Cancer Neoantigen ; Targeted ; Discovery ; MHC
Principal Investigators: (in alphabetical order) |
Christopher Rose, Genentech, United States |
Submitting User: | CMRose5 |
Number of Files: | |
Total Size: | |
Spectra: | |
Subscribers: | |
Owner | Reanalyses | |
---|---|---|
Experimental Design | ||
Conditions:
|
||
Biological Replicates:
|
||
Technical Replicates:
|
||
Identification Results | ||
Proteins (Human, Remapped):
|
||
Proteins (Reported):
|
||
Peptides:
|
||
Variant Peptides:
|
||
PSMs:
|
||
Quantification Results | ||
Differential Proteins:
|
||
Quantified Proteins:
|
||
Browse Dataset Files | |
FTP Download Link (click to copy):
|