Epitope mapping allows the identification of polyclonal antibodies produced as a response to cytotoxins, allergens, neuronal or inflammatory conditions and, in autoimmune diseases to autoantigens. Routine assays for autoimmune response profiling are generally performed by ELISAs and fluorescence immunoassays. Individual assays are performed in microtiter plates, with each well representing a single antigen.
Peptide microarrays provide a powerful approach to study autoimmune disease offering the obvious advantages of a miniaturized assay that can be performed with low volumes of serum. The direct immobilization of peptides on a nitrocellulose surface is the preferred method for this application with PATH®protein microarray slide being the recommended substrate. The thin homogeneous nitrocellulose coating is ideal for immobilization of an array of peptides: a high-load of peptide-probe can be concentrated in one spot increasing assay sensitivity. The random orientation of the probe on the array surface facilitates equal access to different functional domains for the antibodies. The low intrinsic fluorescence background for PATH® results in an increased signal to noise ratio. A detailed protocol for the design of a peptide array for immune response profiling can be found here:
Epitope Mapping Using Peptide Microarray in Autoantibody Profiling. Henkel S, Wellhausen R, Woitalla D, Marcus K, May C. Methods Mol Biol. 2016;1368:209-24. doi: 10.1007/978-1-4939-3136-1_15. PMID: 26614078