KAPPA-MARKER TYPING WITH HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY - IDENTIFICATION OF KAPPA-MARKER SPECIFIC TRYPTIC PEPTIDE FROM THE KAPPA-LIGHT-CHAIN OF IMMUNOGLOBULIN-G

Human serum immunoglobulin G was separated into its heavy and light ch ains by sodium dodecyl sulfate polyacrylamide gel electrophoresis and transferred electrophoretically to a polyvinylidenedifluoride membrane . Peptide fragments liberated from the light chain by in situ digestio n with trypsin were then analyzed by reversed-phase high-performance l iquid chromatography (HPLC). On comparing the HPLC patterns of these f ragments derived from three major kappa marker (Km) types, two distinc t peaks specific for the Km types were detected. Sequencing of the two specific peak peptides confirmed that they were identical to a stretc h comprising residues 191-207 of the immunoglobulin kappa light chain, which contains valine/leucine allotypic variation at position 191.