Figure 8. Identification of a Treg-stimulating ppins76–90 peptide.

(a) Aminoacid sequences of the ppins75–99 (C19-A1) fragment and overlapping 15-residue peptides ppins76–90, ppins78–92, ppins80–94, ppins82–96 and ppins84–98. (b) Conventional Foxp3^negative/eGFP^negative CD4⁺ T cells were isolated from spleens of B6-Foxp3^eGFP mice using magnetic assisted (MACS) and fluorescence assisted (FACS) cell sorting and stimulated for three days with CD3-depleted autologous splenocytes pulsed with the respective ppins-derived peptides as well as two I-A^b-binding control peptides (HBcAg_128-140 and Ova_323-339). In vitro conversion of Foxp3^negative/eGFP^negative CD4⁺ T cells into Foxp3⁺/eGFP⁺ CD25⁺ CD4⁺ T cells was determined by FCM (see Supplementary Protocols). The actual percentages of newly arising Foxp3 expressing CD25⁺ CD4⁺ Treg cells ± SD of a representative experiment (out of two experiments performed) are shown.