Figure 5. Transcytotic capacity of optimized constructs.

(A+B) 1 nM ¹²⁵I radio-labelled VHH or dIgA was applied in the basolateral chamber of polarized MDCK-hpIgR cells (A) or Caco-2 cells (B) grown on transwell inserts. Apical medium was resorbed after each 2 h interval to a maximum of 6 h and quantified separately. Amount of pmol that is transcytosed is plotted against time. Leakage of a non-specific VHH control was deducted from the specific signal (n = 4) (s.e.m.'s are shown for all points). Significance measurements were done by two-way ANOVA.