Fig. 5.

FACS analysis of disaggregated mouse skin mast cells. (A) The x axis corresponds to FITC-conjugated c-kit, and the y axis corresponds to phycoerythrin-conjugated CRHR (nonspecific, recognizes both R1 and R2). The cells labeled in quadrant R3 are positive for both c-kit and CRHR. Quadrant R4 is the negative control and is set for nonspecific fluorescence. R7 (box) contains those cells that did not stain with 7-amino-actinomycin D, the viable cells, and the cell population subsequently sorted for further analysis. (B) Intact mast cell with several granules. Those cells that were double-labeled with both c-kit and CRHR and did not take up 7-amino-actinomycin D were sorted by using a MoFlo instrument and collected in PBS/0.5% BSA. The cells were prepared on glass slides and stained with toluidine blue. The arrow indicates the nucleus, and the arrowhead points to the mast cell granules.