Objective: To investigate the effects of recombinant human type XVII collagen (RHCXVII) on the proliferation and adhesion of primary human keratinocytes (HPKCs) and to observe its clinical efficacy and safety in bullous pemphigoid (BP). Methods: The RHCXVII was produced by genetic recombination technology and characterized by Fourier transform infrared (FTIR) spectroscopy. HPKCs were obtained from human foreskin and seeded onto culture plates coated with RHCXVII at concentrations of 10, 50 and 100 mu g/ml. The proliferation and relative adhesion of HPKCs were assessed by Cell Counting Kit-8 (CCK-8) and adhesion assays, respectively. Trajectories and velocities of HPKCs were recorded using a living cell imaging platform. To assess the effects of RHCXVII on HPKCs, E-cadherin, integrin alpha 6 and laminin alpha 3 mRNA levels were measured using reverse transcription-polymerase chain reaction (RT-PCR) assays. The patient test sites were treated with RHCXVII, while the contralateral sides served as controls. This was performed in combination with systemic glucocorticoid treatment. Bilateral wound healing was recorded at various time points and the efficacy in BP was assessed. Results: RHCXVII exhibited the anticipated structural characteristics of recombinant collagen and was deemed suitable for utilization in the present study. HPKCs demonstrated robust growth in culture plates precoated with RHCXVII, expressing keratin 15 (K15). After 3, 5 and 7 days, RHCXVII at a concentration of 10 mu g/ml significantly promoted the proliferation of HPKCs (P<0.05). Furthermore, the optimal relative adhesion of HPKCs was observed when cells were cultured on RHCXVII at a concentration of 100