From Black Box to Clear Insight: A Systematic Review of Human and Porcine Splenic Ex Vivo Perfusion Models

The development of ex vivo perfusion models has significantly advanced our understanding of organ function, facilitating research into various health conditions. This review examines the use of porcine and human splenic ex vivo perfusion models and their contributions to biomedical research. We conducted a systematic literature review following Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines. Two independent reviewers screened titles, abstracts, and full texts to select studies on human and porcine spleen ex vivo perfusion models that met our inclusion criteria. Nineteen studies using normothermic ex vivo perfusion on porcine spleens with different perfusion durations were reviewed. These studies demonstrated the adaptability and utility of these models in biomedical research. The earliest use of this model dates to 1966, with significant advancements over time. This progress has established the model as a crucial tool for studying bacterial pathogenesis. Both models have greatly enhanced our understanding of previously unknown mechanisms in haematology, parasitology, and microbiology. Currently, only two centres use the human splenic ex vivo perfusion model, with studies lasting up to six hours. Extending this duration could broaden the research scope, especially in microbiology and clinical immunology. Expanding the model's use could reduce reliance on animal models, aligning with the principles of the 3Rs: replacement, reduction, and refinement.