ABSTRACT
Objective:To develop an efficient and rapid method for the isolation and cultivation of human scalp dermal papilla cells from small specimens.Methods:Hair-bearing skin specimens measuring 0.5 cm × 0.5 cm -0.5 cm × 1 cm in size were obtained from the scalp of 3 patients with pigmented nevus and 6 with sebaceous nevus during surgery in Department of Dermatology, the First Hospital Affiliated to Army Medical University from September 2018 to January 2019. The subcutaneous fat layer containing hair follicles was cut out of the specimens, and hair follicles were sorted with ophthalmic forceps, which were subsequently digested with 0.6% dispase Ⅱ for 30 minutes, then with 0.2% collagenase Ⅳ at 37 ℃ for 30 - 60 minutes, and were centrifuged to obtain hair papillae. Morphological observation was performed on the isolated hair papillae, and dermal papilla cells were cultured, passaged and identified.Results:Under the microscope, the hair papillae isolated by two-step enzyme digestion of small scalp specimens were intact, and showed an inverted pear-like shape, and residual dermal sheaths could be observed around some hair papillae. However, no hair papilla was isolated by one-step enzyme digestion. With the two-step enzyme digestion method, the hair papilla separation rate was 60.8% ± 2.1%, the adherence rate of the dermal papilla cells at 72 hours was 86.6% ± 3.9%, the time for cells to emigrate out of hair papillae was 0.5 - 3.0 days, the total operation duration was 2.0 - 3.0 hours, and the actual operation duration after subtraction of digestion duration was 1.0 - 1.5 hours. The dermal papilla cells isolated by the two-step enzyme digestion method could grow in an aggregative pattern in early stage, but grew in a non-aggregative pattern after 8 passages.Conclusion:The two-step enzyme digestion of small specimens is a simple and efficient method for isolating human scalp dermal papilla cells.