Nasal epithelial zonation and turbinate morphology in infant common marmosets (Callithrix jacchus).

The nasal cavity plays a critical role in respiration and olfaction, functions supported by its turbinate architecture and epithelial distribution. The turbinates-primarily composed of the maxilloturbinate and ethmoturbinate-expand the intranasal surface area and provide a structural foundation for epithelial types. Although the common marmoset(Callithrix jacchus) is widely used as a nonhuman primate model in translational research, postnatal nasal turbinate structure and epithelial zonation have not been fully characterized. In this study, we compared turbinate morphology and epithelial zonation between infant (≤ postnatal day 28) and adult (> 1 year) marmosets using high-resolution micro-computed tomography and histological analysis. In infancy, the maxilloturbinate lacks the scroll-like structure of adults, and The ethmoturbinate is limited in anterior extension and shows no evident branching, indicating immaturity. Epithelial zonation is already characterized in infancy, resembling the adult pattern. The nasal cavity epithelia comprise squamous epithelium (SE), nasal transitional epithelium (TE), respiratory epithelium (RE), and olfactory epithelium (OE) in anterior-to-posterior order. In contrast to adults, infant SE shows high proliferative activity, while RE exhibits sparse goblet cells, reflecting functional immaturity. These findings provide the first developmental map of turbinate architecture and epithelial distribution in the marmoset and serve as a reference for future studies of primate nasal biology.