Analysis of naturally processed peptides eluted from HLA DRB1*0402 and *0404.
Understanding the structural features of naturally processed peptides found within the major histocompatibility complex (MHC) class II peptide binding groove from disease-associated MHC molecules may provide insights into the nature of potential disease-related antigens. Class II MHC/peptide complexes were purified by immunoaffinity from transformed B cell lines homozygous for DRB1*0404 (an allele associated with rheumatoid arthritis) and *0402 (a closely related allele not associated with this disease). Peptides were eluted at acidic pH, fractionated by reversed phase HPLC, and analyzed by capillary electrophoresis. Those fractions containing a single dominant peptide were sequenced by automated Edman degradation and tandem mass spectrometry. The predominant peptide species identified came from non-polymorphic regions of the HLA class I molecules expressed by each cell line. Peptides from DRB1*0404 were found to be nested clusters derived from positions 26-43 of the HLA-B and -C alpha-chain. DRB1*0402 contained as the predominant peptide species a nested cluster from positions 129-145 of the HLA-B alpha-chain. The primary structure of the class I derived peptides was consistent with that seen by peptides exhibiting promiscuous DR binding behavior. Processing of MHC-derived peptides by MHC class II molecules is a common occurrence in the transformed B cell lines analyzed.
Department of Veterans Affairs Medical Center, Portland, OR 97207, USA.
J B
JB
Hayden
A L
AL
McCormack
J R
JR
Yates
M P
MP
Davey
D001402:B-Lymphocytes / Q000276:immunology*; D002461:Cell Line, Transformed; D002851:Chromatography, High Pressure Liquid; D004586:Electrophoresis / Q000379:methods; D006684:HLA-DR Antigens / Q000737:chemistry*; D059811:HLA-DRB1 Chains; D015395:Histocompatibility Antigens Class I / Q000737:chemistry*; D000949:Histocompatibility Antigens Class II / Q000737:chemistry*; D006801:Humans; D013058:Mass Spectrometry; D010455:Peptides / Q000302:isolation & purification*
D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; C553506:HLA-DRB1*04:02 antigen; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D010455:Peptides