HLA-B27 peptides eluted from human splenocytes and blood cells reveal lower values for Arg at P2 compared to in vitro grown cell lines

Peptides eluted from HLA-B2705 human spleen cells and peripheral blood cells (PBL) were pool sequenced by solid-phase Edman degradation. Only 67.6% (splenocytes) and 11.2% (PBL) peptides contained Arg at P2. These values obtained from "fresh" human material are lower in comparison with previously published data reported for various in vitro long-term cultured cell lines. Possibly the difference is due to the cell type examined in this study.