Preliminary Findings from an Ovine Model of Blood Component Therapy Developed to Investigate Transfusion-Related Acute Lung Injury

Aim To develop an ovine model of blood component therapy (BCT). The model will be used to study adverse reactions including transfusion-related acute lung injury. Methods Sheep were first infused with either saline (healthy sheep) or lipopolysaccharides (LPS) (sepsis sheep). An hour after the first infusion was completed sheep were infused with BCT of either saline (control), day-1 pool of heat-treated supernatants from human wholeblood platelets (d1-S/N) or day-5 pool (d5-S/N). Results LPS-infusion resulted in decreased circulating neutrophils (PMNs) corresponding with pulmonary sequestration of PMNs. Infusion of d1- and d5-S/N into healthy sheep resulted in increased circulating PMN counts. Infusion of human BCT caused only mild pulmonary injury which was most severe when d5-S/N was infused into septic sheep. D5-S/N also caused mild injury (average injury ≥1) more often than d1-S/N. Conclusion These preliminary data indicate that sheep tolerate the infusion of human platelet supernatants, and therefore are potentially a suitable large animal model to study the effects of BCT. Mild pulmonary injury seen more often with stored blood product (d5-SN) may represent a mild TRALI, however further study is required to confirm this