Introduction: The Amniotic Membrane (AM) Bank at The University of Osaka Hospital (UOH) was established in 2017. The AM has been shown to offer significant benefits in ophthalmic treatments owing to its anti-inflammatory, anti-fibrotic, and epithelialization-promoting properties. This report describes the activities of the AM Bank and its clinical achievements in AM transplantation.
Methods: Informed consent was obtained from healthy donors scheduled for cesarean sections at UOH. The AM was harvested from these donors and processed at the Cell Processing Center (CPC). The membranes were sectioned into 4–5 cm square pieces and stored at −80 ℃ in the biospecimen storage facility. The preserved AM were subsequently used for ophthalmic surgeries at UOH. We retrospectively analyzed transplant data from September 2017 to December 2024 using a standardized “AM Transplant Report” form developed by Japanese transplant coordinators. Quarterly monitoring was performed to assess adverse events associated with AM transplantation. The bank's operations　including preparation, storage, transportation, and quality control were also overseen as part of the safety and quality assurance process.
Results: A total of 269 AM tissues were harvested from six donors (mean age, 35.8 ± 4.6 years; mean yield, 44.8 ± 8.6 tissues per donor), all of whom tested negative for infectious disease screening. Of these, 208 tissues were allocated for ophthalmic use, and 192 were successfully transplanted.
Among the recipients, 112 (58%) were men and 80 (42%) women, with ages ranging from 7 to 91 years (mean, 60.4 ± 20.9 years). The three most frequent indications for AM transplantation were pterygium (41 patients, 21%), ocular pemphigoid (33 patients, 17%), and thermal or chemical injuries (27 patients, 14%). The number of transplants increased from 2017 to 2019 and peaked at 32 cases in 2019. However, a 28–35% decline occurred between 2020 and 2022 (23, 21, and 22 cases annually, respectively), potentially due to the COVID-19 pandemic. In recent years, the number of AM transplants has gradually increased. Importantly, no AM transplantation-related adverse events were observed during the study period.
Conclusions: This study summarizes the 8-year outcomes of the AM Bank at UOH. Although AM transplantation rate temporarily decreased during the COVID-19 pandemic, a resurgence has been observed. As of December 2024, the bank has facilitated 192 ophthalmic procedures, with no reported adverse events. We will continue to prioritize the safety, consistency, and quality of the bank’s activities.