Séminaire de Heba Elseedy

Vendredi 9 octobre 2026 à 11h, Salle Henri Gastaut, INT

Heba Elseedy, Dysbrain Team (Institut de Neurosciences de la Timone)

3D Mapping of the Oxytocin and Vasopressin Systems in Primate Brain and Rodent Whole Body Using iDISCO+ / iNSIGHT Clearing and mesoSPIM Light-Sheet Imaging

Abstract: Mapping neuropeptide systems like oxytocin (OT) and vasopressin (AVP) across entire tissues has long been limited by the constraints of classical histology, thin sections, partial sampling, and loss of 3D spatial context. In this talk, I will present the imaging pipeline I am setting up to generate comprehensive 3D maps of the OT/AVP systems at the whole-brain level in macaques and at the whole-body level in rodent pups, including applications to mRNA detection.
This talk will cover two key methodological components that may be unfamiliar to the group. The first is the combination of iDISCO+ and INSIGHT: iDISCO+ is a solvent-based tissue clearing protocol that renders large tissue volumes optically transparent, while INSIGHT is a recently developed immunolabeling strategy that uses superchaotropes and host-guest chemistry to drive deep, homogeneous penetration of antibodies and mRNA probes, even in centimeter-scale tissues. Together, they allow us to label and clear whole organs or bodies in a way that was not previously achievable with standard protocols. The second component is mesoSPIM, a light-sheet microscope specifically designed for imaging large cleared specimens at mesoscale resolution. I will explain how light-sheet illumination works, why mesoSPIM is particularly well suited for the size of our samples, and how it differs from conventional confocal systems.
By combining these approaches, we aim to build the first complete 3D neuroanatomical maps of the OT and AVP systems, at both the protein and mRNA levels, in tissues ranging from rodent pups to primate brains, providing a powerful resource for understanding the neural basis of social behavior.