Encephalitogenic Peptides from Spinal Cord

IN a recent symposium on experimental allergic encephalomyelitis there was considerable discussion on the size of encephalitogenic factors from brain and spinal cord 1–4 . We have fractionated extracts from bovine spinal cord by gel-filtration with phenol–acetic acid–water. This solvent system was introduced by Synge and colleagues 5–7 for the fractionation of peptides on ‘Sephadex G -75’. It is a strongly dissociating solvent which prevents adsorption of peptides on ‘Sephadex’, and gel-filtration in this solvent can be used to estimate the molecular size of peptides as there is an approximately linear relationship between the relative elution volume and the log of molecular weight 8,9 . This communication describes a typical fractionation of basic polypeptides which were found to produce experimental allergic encephalomyelitis in guinea-pigs.