Table 1.

Assessment of Ax488-labeled Tac-furin and Tac-furin/ADA distribution by fluorescence ablation

	Fluorescence ablation (% ± SE)
	Steady state	Postendocytic quenching by HRP-Tf	Postendocytic quenching by HRP
Cell Line	Pulse: Ax488 anti-Tac, 5 min	Pulse: Ax488 anti-Tac, 5 min	Preincubation: HRP, 15 min
	Chase: HRP-Tf, 2 h	Chase: HRP-Tf, 10 min	Pulse: Ax488-anti-Tac, 5 min
			Chase: HRP, 10 min
WT	12 ± 2	20 ± 4	64 ± 8
ADA	15 ± 3	72 ± 10	15 ± 2

Cells were pulsed with Ax488-anti-Tac antibody, washed, and chased in the presence of HRP-Tf or HRP for the indicated times. At the end of the chases, cells were placed on ice and incubated with H₂O₂ and DAB or medium 1 (control). The extent of DAB-mediated fluorescence ablation is expressed as the percentage of total fluorescence intensity of control cells. For comparison, quenching of Ax488-Tf by HRP-Tf was 77–80%.