FIG. 1.

The percentage of cells with positive signals for ALPL was calculated using image analysis algorithms. A cartoon representation of the analysis is shown illustrating the basic concept (A). Fluorescence signals were assigned to the nearest Hoescht-stained nuclei, establishing parent-child relationships between the two images (B, merged for illustration purposes). “Low/no-signal” cells exhibited no fluorescence events in the region of interest above a minimum threshold value (A1, B1). “Positive” signals varied in type and intensity and included point signals (A2, B2), punctate, compressed speckling (A3, B3), and widespread fluorescence throughout the perinuclear region (A4, B4). All of these categories were included when calculating the percentage of positive cells. ALPL, alkaline phosphatase. Color images available online at www.liebertpub.com/tea