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EpiScreen™ MAPPs MHC Class II Associated Peptide Proteomics

EpiScreen™ MAPPs  MHC Class II Associated Peptide Proteomics

EpiScreen™ MAPPs detects and identifies MHC Class II bound peptides processed and presented by dendritic cells (DCs) from therapeutic proteins/mAbs. Combined with our ex vivo T cell epitope mapping assay, peptides can be identified that are recognised by CD4+ T cells with the potential to trigger an immune cascade, causing T cell proliferation and leading to anti-drug antibody formation.

Together these technologies provide an approach to designing biopharmaceutical product candidates with reduced risk of immunogenicity.

Ideal for use:

• To assess relative immunogenicity potential of new product candidates with known anti-drug activity (ADA) inducers
• With pharmacologically active products that negatively impact ex vivo T cell functional methods
• With large/complex product candidates to better inform ex vivo T cell epitope mapping assay design
• As a pre-filter for putative T cell epitopes – more predictive than in silico methods

The MAPPS assay

CD14 positive mononuclear cells are purified from PBMC and differentiated into immature DCs using GMCSF and IL-4. IDCs are loaded with test proteins and then matured with LPS.

MHC Class II presentation
The DCs take up and process the proteins, presenting them as linear peptides bound in the groove of MHC class II.

After 24 hours incubation with the test sample and LPS, the DCs are lysed and MHC class II bound peptide complexes are captured by immunoprecipitation using a pan-HLA-DR antibody. Naturally processed and presented peptides, from the test sample, are eluted from the captured MHC molecules for subsequent analysis by nano-LC-MS/MS.