Splenic development and injury in premature lambs supported by the artificial placenta

The purpose of this study is to evaluate splenic effects during artificial placenta (AP) support. AP lambs (118–121 d, n = 14) were delivered and placed on the AP support for a goal of 10–14 days. Cannulation used right jugular drainage and umbilical vein reinfusion. Early (ETC; 115–120 d; n = 7) and late (LTC; 125–131 d; n = 7) tissue controls were delivered and immediately sacrificed. Spleens were formalin fixed, H&E stained, and graded for injury, response to inflammation, and extramedullary hematopoiesis (EMH). CD68 and CD163 stains were used to assess for macrophage activation and density. Clinical variables were correlated with splenic scores. Groups were compared using Fisher's Exact Test and descriptive statistics. p