Effects of peptide fraction and counter ion on the development of clinical signs in experimental autoimmune encephalomyelitis

摘要: The most commonly used immunogen to induce experimental autoimmune encephalomyelitis is MOG35-55, a 21-residue peptide derived from myelin oligodendrocyte glycoprotein (MOG). In studies, mice exhibit chronic disease; however, in some studies show transient disease. One variable that not often controlled for the fraction of purified MOG material, which can vary less than 50% over 90%, with remainder mass primarily comprised counter ion purification. We compared development clinical signs female C57Bl6 immunized two commercially available MOG35-55 peptides similar purity but different (MOG-A being 45%; MOG-B 72%). A single immunization MOG-A induced disease course recovery at later stages, whereas significantly lower average scores despite higher content. addition booster increased severity both preparations, and reduced day onset using MOG-A. To determine if could influence disease, we MOG-B-containing trifluoroacetate acetate. Although incidence were similar, occurred approximately 5 days earlier use trifluoroacetate. These results demonstrate differences may be due part levels ions present material. findings underscore fact knowledge as critical when sources. The (EAE) glycoprotein. Subtle variations protocols type onset, severity, overall incidence. hypothesized variance contribute those differences. Surprisingly, preparation high (72%) resulted EAE having only 45% fraction. Replacement (TFA), purification, acetate delayed onset. are purity, particularly image shows TFA molecules (not scale) hypothetically binding positively charged residues MOG.