Safety of direct injection of oligodendrocyte progenitor cells into the spinal cord of uninjured Göttingen minipigs

OBJECTIVE This study was conducted as a final proof-of-safety direct injection of oligodendrocyte progenitor cells into the uninjured spinal cord prior to translation to the human clinical trials. METHODS In this study, 10⁷ oligodendrocyte progenitor cells (LCTOPC1, also known as AST-OPC1 and GRNOPC1) in 50-μL suspension were injected directly into the uninjured spinal cords of 8 immunosuppressed Göttingen minipigs using a specially designed stereotactic delivery device. Four additional Göttingen minipigs were given Hanks’ Balanced Salt Solution and acted as the control group. RESULTS Cell survival and no evidence of histological damage, abnormal inflammation, microbiological or immunological abnormalities, tumor formation, or unexpected morbidity or mortality were demonstrated. CONCLUSIONS These data strongly support the safety of intraparenchymal injection of LCTOPC1 into the spinal cord using a model anatomically similar to that of the human spinal cord. Furthermore, this research provides guidance for future clinical interventions, including mechanisms for precise positioning and anticipated volumes of biological payloads that can be safely delivered directly into uninjured portions of the spinal cord.