Figure 1
From: Life-extended glycosylated IL-2 promotes Treg induction and suppression of autoimmunity
IL-2 variant design and in vitro functional analysis. (A) A scheme structure of the recombinant IL-2 S2A. The human IL-2 encoding sequence is flanked by two highly glycosylated fragments. S2A sequence also includes the IL-2 signal peptide at the N-terminal and His-tag sequence at the C-terminal. (B) S2A encoding plasmids were transfected into HEK293F cells, and protein was purified from media using the Ni-ion exchange column. Following purification, purity and size were determined by running eluted fraction on SDS-PAGE. (C) A representative ELISA binding curve (fitted to 4-parameter logistic) using IL-2 ELISA kit (Biolegend) (D) A representative CTLL-2 proliferation test, done using MTT assay (fitted to 4-parameter logistic. (E) Aggregated results of 5 independent CTLL-2 assays for different preparations of commercial IL-2 (Proleukin) and S2A. Mann–Whitney U test was used to determine significance (solid line—mean, crushed line—median; *, P < 0.05).
