Epithelial Skirt and Bulge of Human Facial Vellus Hair Follicles and Associated Merkel Cell-Nerve Complex

The study examined the morphological variations in the bulge areas of human facial vellus hair follicles, particularly focusing on the presence and distribution of Merkel cells and associated nerve complexes. In anagen phase vellus hairs, bulge areas exhibited dense aggregations of CAM5.2 reactive Merkel cells, while in the telogen phase, the bulge was less distinct, yet Merkel cells remained abundant. The epithelial hood at the sebaceous gland level typically displayed a skirt-like structure, with variations such as bamboo joints and tulip flower configurations, where Merkel cells were sparsely present. Additionally, palisading stockade-like nerve endings were observed around the follicular epithelium, particularly under the skirt and around the bulge areas.