Purification and characterization of endogenous peptides extracted from HLA‐DR isolated from the spleen of a patient with rheumatoid arthritis
Gordon RD., Young JA., Rayner S., Luke RWA., Crowther ML., Wordsworth P., Bell J., Hassall G., Evans J., Hinchliffe SA., Culbert EJ., Davison MD.
AbstractWe have purified HLA‐DR from the spleen of a patient with rheumatoid arthritis. The patient had Felty's syndrome and was heterozygous for the DR4Dw4 antigen. We have isolated endogenous peptides from purified HLA‐DR molecules. The peptides were purified by reverse phase HPLC and the major peaks were subjected to N‐terminal sequencing. The peptides were derived from a variety of proteins: human serum albumin, human erythroid protein 4.1, 60S ribosomal proteins L31 and L35, VCAM‐1, human immunoglobulin λ chain and cathepsin‐S. A peptide corresponding to the sequence of human serum albumin (HSA) residues 106–120 was synthesized and shown to bind to HLA‐DR4Dw4 (IC50 = 1.41 μM). We have confirmed and refined current ideas about the structural motif for the binding of peptides to HLA‐DR and HLA‐DR4Dw4.