Figure 2.

Receptor binding and pharmacokinetic properties of various transferrin-fusion proteins. Fusion proteins with different linkers were recombinantly produced inHEK293 cells. IC₅₀ values from competitive receptor binding assays were performed in IM-9 cells for GH receptor (GHR), NSF-60 cells for G-CSF receptor (G-CSFR), and Caco-2 cells for Tf receptor (TfR) using ¹²⁵I-labeled proteins. The half-life values were determined following intravenous administration of fusion proteins to CF1 mice in the absence and presence of co-administered GH or Tf. The values represent mean ± standard deviation (n=3 to 4).