Introduction: Necroptosis was previously found as a mechanism of beta-cell death in diabetes and in human islet culture. Necrostatin-1 (Nec-1), a potent inhibitor of necroptosis, could reduce human islet necroptosis. This study aims to assess whether Nec-1 could improve the survival of pre-weaned porcine islets (PPIs) during maturation culture, and whether it affects their insulin secretory function. Methods: PPIs were isolated from pancreata of 4-11-day-old, pre-weaned Yorkshire pigs and cultured in optimized islet culture media (37°C, 5% CO2) for 3 days. At day 3, the islets were divided into 2 groups, in islet culture media alone (n=6) or supplemented with Nec-1 (100µM, Sigma, n=5), and then cultured until day 7. Islet recovery was calculated as the percentage of IEQ per gram of pancreatic tissue on day 7 compared to day 3. Flow cytometry (NovoCyte 3000VYB) was used to determine islet cellular viability, composition, GLUT2 expression and differentiation. In vitro function was determined by glucose-stimulated insulin release assay. Data was expressed as mean ± SEM and evaluated using ANOVA with p<0.05 considered statistically significant. Results & Discussion: Islet recovery was significantly higher in Nec-1 treated group (control=51.3±10.2% vs. Nec-1=112.8±8.4%, p<0.01, Figure 1). Nec-1 treated islets had a two-fold increase in the percentage of β-cells compared to untreated islets (control=8.9±1.3% vs. Nec-1=17.2±1.4%, p<0.01). Additionally, GLUT2 expression in β-cells was significantly elevated in Nec-1 treated group (control=29.9±3.2% vs. Nec-1=55.1±0.7%, p<0.05). A substantial increase in insulin secretion in response to glucose challenge was observed when the islets were cultured with Nec-1 (2.8 mM glucose: control=0.9±0.2 pg/ng vs. Nec-1=13.8±2 pg/ng, p<0.01; 28 mM glucose: control=2.3±1.6 pg/ng vs. Nec-1=38.8±5.2 pg/ng, p<0.01; SI: control=2.5±0.3 vs. Nec-1=5.3±0.6, p<0.01). Conclusion: Identifying cytoprotective agents that could maintain islet quantity and quality during extended culture is critical to optimize the current pre-transplant protocol. Our data showed that Nec-1 improved islet recovery, increased proportion of endocrine cells, increased GLUT2 expression in β-cells, and improved insulin response to glucose. We believe that Nec-1 supplementation in culture media will enhance islet quality before transplantation. Future studies will be done to titrate the most effective dose of Nec-1, and evaluate these islets in rodent transplant models of Type 1 diabetes. Juvenile Diabetes Research Foundation.