(A) UAN nanoparticles encapsulating FITC and conjugated to different I domains were delivered to HeLa and MDA-MB-231 cells. (B) Immunofluorescence flow cytometry measurement of the delivery into HeLa of UAN(FITC) with no I domain, WT, or I domain variants (n = 3). (C) The levels of ICAM-1 expression in HeLa, MDA-MB-231, and KTC-1 cells were measured by mAb R6.5 (open histogram) or with secondary antibody alone as a control (filled histogram). (D) Immunofluorescence flow cytometry measurements of F265S/F292G-UAN(FITC) binding to HeLa, MDA-MB-231, and KTC-1 cells.