Design of experiment (DOE) was utilized to optimize a peptide microarray to test autoantibodies in serum against various components of the myelin sheath. Incorporating the ideal assay conditions from a single DOE experiment versus multiple sequential experiments resulted in a reproducible serum assay with low variability, low nonspecific background, and a high level of distinction between multiple sclerosis (MS) and normal samples.
A number of peptides were tested, and a minimum set of peptides was found that achieved a sensitivity of 90 percent. Autoantibodies against each individual peptide were elevated in at least 35 percent of the individual MS patients tested. All peptides had relevance to disease etiology from published references. Future studies will assess the sensitivity of these peptides for an MS serum diagnostic by testing individual normal serum samples as well as individual samples from patients with other neurological disorders and identifying the false positive rate.