Honorable Mention Oscar Cazares, University of California, Santa Cruz

Confocal microscope image of a cluster of mammary alveoli structures at pregnancy day 17.5 with myoepithelial basal cells (marked by ACTA2, green) wrapping around an inner layer of milk-producing luminal cells (marked by milk, magenta); nuclei are marked by DAPI in blue. During pregnancy, alveolar progenitor cells undergo rapid expansion to generate the luminal cells in these milk-producing structures, while basal cells provide structural and contractile support for milk secretion.

Products used: Antigen Unmasking Solution, Citrate-Based – (H-3300-250), VECTASHIELD^® PLUS Antifade Mounting Medium with DAPI – (H-2000)