Cover Caption: Cyclic immunofluorescence, a highly-multiplexed high-content imaging method for probing cellular network is described (see Lin, pp. 8–10). Background: Color composite images from 4 rounds of cyclic immunofluorescence on the same MCF10A cells. Twelve different antibodies in total were used for labeling cytoskeletons, transcription factors, cell cycle regulators and receptors. Foreground: Flowchart of cyclic immunofluorescence method. The culture cells in 96-well plates are passed through cycles of (1) antibody incubation, (2) imaging, (3) data analysis and (4) dye bleaching. Chemical Structure: Antibodies directly conjugated with fluorophores are required for cyclic immunofluorescence to avoid cross-reactivity from secondary antibodies. Alexa fluor 488 (shown here), 555 & 647 all can be effectively removed by dye bleaching step. Cover design by Darryl Leja.