Fig. 1

Optical clearing of mammary tissue. a Experimental procedure and timelines for optical clearing of mouse mammary tissue. Black arrows show the stage at which (optional) immunostaining may be performed. The experimental timeline can be altered depending on the size and nature of the tissue, and the degree of transparency required. b Transmission images of whole abdominal (fourth) mammary glands (virgin and lactating) before and after clearing using the passive clarity technique (PACT) with rapiclear (RC) or sorbitol refractive index matching solution (sRIMS), clear unobstructed brain imaging cocktails (CUBIC) or the see deep brain (SeeDB) clearing protocols. c Volume changes resulting from optical clearing of virgin and lactating mammary tissue. Values are representative of measurements from three tissue pieces from each clearing protocol at each developmental time point. See additional file 18 for a high resolution version of these PDFs and http://rdcu.be/lT3Z for additional high resolution examples of these imaging techniques [38]