A. HT1080lacZ-K15 cells overexpressing FL-L1CAM before and after antibody-induced internalization. B. and C. HT1080lacZ-K15 cells 60 min chased at 37°C co-expressing FL-L1CAM or SV-L1CAM together with fluorophore-tagged LAMP1, KIF16B, or TGN38. Arrows indicate internalized L1CAM in selected vesicles that co-localized with compartment markers (Scale bars: 10 µm (A to C)). D. Relative distribution of L1CAM-labeled vesicles in lysosomes (GFP-LAMP1: SV-L1CAM: 24.0%±4.2% SEM; FL-L1CAM: 18.6±4.0% SEM; *p = 0.022, n = 30 each), early endosomes (YFP-KIF16B: SV-L1CAM: 43.3%±5.8% SEM; FL-L1CAM: 53.4%±5.1% SEM; p = 0.194, n = 30 each), retrograde and recycling endosomes (YFP-TGN38: SV-L1CAM: 35.5%±6.3% SEM; FL-L1CAM: 54.7%±5.2% SEM; **p = 0.002, n = 20 each) Data was calculated from three (FL- or SV-L1CAM+GFP-LAMP1, n = 30 each) or two independent experiments (FL- or SV-L1CAM+YFP-TGN38, n = 20 each) and displayed as means ± SEM (columns ± bars), p values were determined by Mann-Whitney Rank Sum Test.