Figure 3.

Bidirectional transcytosis of FcY. FcRY-IMCD and untransfected IMCD cells were grown as polarized monolayers on permeable filter supports. [¹²⁵I]FcY or [¹²⁵I]Fcγ was added to the loading surface to a final concentration of 100 nM with or without unlabeled competitor or nocodazole. Medium from the nonloading surface was collected after 90 min, and levels of [¹²⁵I] radioactivity in the acid-insoluble fraction were determined. (A) Apical-to-basolateral transcytosis. (B) Basolateral-to-apical transcytosis. Both sets of histograms represent the mean ± SEM of triplicate measurements from a representative experiment. Similar results were obtained in two independent experiments. *p < 0.05, **p < 0.001 relative to [¹²⁵I]FcY, pH 6.0.