SRM ASSAY FOR PD-L1

摘要

The current disclosure provides for specific peptides, and derived ionization characteristics of the peptides, from the PD-L1 protein that are particularly advantageous for quantifying the PD-L1 protein directly in biological samples that have been fixed in formalin by the method of Selected Reaction Monitoring (SRM) mass spectrometry, or what can also be termed as Multiple Reaction Monitoring (MRM) mass spectrometry. Such biological samples are chemically preserved and fixed wherein said biological sample is selected from tissues and cells treated with formaldehyde containing agents/fixatives including formalin-fixed tissue/cells, formalin-fixed/paraffin embedded (FFPE) tissue/cells, FFPE tissue blocks and cells from those blocks, and tissue culture cells that have been formalin fixed and/or paraffin embedded. PD-L1 peptides having modified or unmodified residues can be quantitated. An example of a modification of a PD-L1 fragment peptide is a phosphorylated tyrosine, threonine, serine, and/or other amino acid residues within the peptide sequence.