Figure 9.

Localization of the GYEVI construct of human CD63 in rescued mocha cells expressing the δ subunit of AP-3. A stably transfected mocha cell line expressing the δ subunit of AP-3 was transiently transfected with a ΔpMEP construct containing cDNA encoding the human CD63/LIMP-I, GYEVI construct. After treating the transfected cells with 3 μM CdCl₂ to induce protein expression they were double labeled, for indirect immunofluorescence localization with a mouse mAb to human CD63 (A) and with a rabbit polyclonal antibody to the δ subunit of AP-3 (B). Bar, 20 μm. (C) Cells that were expressing the GYEVI construct were then counted and grouped according to the presence of intracellular human CD63 or only cell surface human CD63 and the presence or absence of detectable δ subunit of AP-3. The data shown in the histogram represent the mean of two experiments. In the two experiments the counted numbers of human CD63-positive cells showing only surface expression were 208 and 349. The counted numbers of CD63-positive cells also showing intracellular localization of human CD63 were 91 and 44.