PT - JOURNAL ARTICLE AU - James A. Sargent AU - Victoria HJ Roberts AU - Jessica Gaffney AU - Antonio E. Frias TI - Clarification and confocal imaging of the non-human primate placental micro-anatomy AID - 10.1101/330647 DP - 2018 Jan 01 TA - bioRxiv PG - 330647 4099 - http://biorxiv.org/content/early/2018/05/24/330647.short 4100 - http://biorxiv.org/content/early/2018/05/24/330647.full AB - Placental function is essential for the development of the fetus, and is – in part – related to the 3D arrangement of the villous and vascular geometry. Recent advances in tissue clarification techniques allow for deep high-resolution imaging with confocal microscopy without altering the spatial characteristics of the tissue. These image stacks can be analyzed quantitatively to provide insights regarding the villous and vascular micro-anatomy as well as the interrelationships between the two. However, such analyses require optimization of the tissue preparation, immuno-labeling, and clarification protocol in order to provide reliable results suitable for the detection of subtle differences in pathologic pregnancies. Placental and fetal development are similar between human and non-human primate pregnancies, with the latter serving as a reliable, validated, highly-controlled, well-characterized translational model for the former.We present a protocol for the preparation, immuno-labeling, and clarification of the non-human primate placenta optimized for confocal microscopy and subsequent quantification of the micro-anatomic structures.