Optimized extended PCLS culture system extends tissue viability up to two weeks

Precision-cut liver slice (PCLS) technology has long been regarded as a promising ex vivo platform because it preserves the native multicellular architecture of liver tissue. However, widespread adoption has been limited by poor tissue longevity, technical variability, and restricted access to viable human liver specimens. In most previous studies, cultures rarely remained viable beyond 72 hours.

In a recent study published in eGastroenterology, Dr. Z Gordon Jiang and colleagues from Harvard Medical School established an optimized extended PCLS culture system capable of maintaining viable human liver tissue for up to two weeks. The work provides a major methodological advance for modeling chronic liver injury, tissue remodeling, and regeneration in a human-specific context.

Technical refinements enable prolonged tissue viability

The investigators processed 25 explanted human livers from diverse etiologies, including alcohol-associated liver disease, metabolic dysfunction-associated steatohepatitis (MASH), primary sclerosing cholangitis (PSC), hepatitis B virus (HBV)-related disease, and non-fibrotic controls.

Several experimental innovations contributed to the improved culture performance. These included compression-assisted vibratome slicing to generate more uniform tissue sections, hyperoxygenation recovery after slicing, and optimized oxygen and nutrient delivery during culture. Together, these refinements substantially improved reproducibility and extended tissue survival.

Importantly, the study also introduced a multidimensional viability assessment framework. Instead of relying solely on destructive ATP assays, the authors combined whole-plate imaging, live/dead whole-mount staining, and Seahorse metabolic analysis to dynamically monitor tissue health over time.

Dynamic remodeling reveals disease-relevant biology

A key finding of the study is that extended PCLS culture is not simply maintaining static tissue architecture. Rather, the cultured liver slices undergo active multicellular remodeling that mirrors important pathological processes observed in chronic liver disease.

Histological analyses showed hepatocyte detachment, reduced albumin production, and progressive dedifferentiation during culture. Meanwhile, healthy donor-derived slices developed progressive portal and bridging fibrosis by day 7, demonstrating spontaneous fibrogenesis within the ex vivo system.

Notably, cirrhotic liver-derived PCLS exhibited increasing KRT19-positive ductular cells during culture, consistent with ductular reaction and epithelial plasticity. In contrast, healthy liver slices showed evidence of hepatocyte regenerative clusters. These findings suggest that the model can simultaneously capture regeneration, fibrosis, and biliary remodeling within intact human liver tissue.

Translational implications for liver disease research

The study highlights the growing importance of human-derived New Approach Methodologies (NAMs) in biomedical research. Because PCLS retains native immune cells, stromal components, and spatial tissue organization, it may provide advantages over conventional cell culture systems and some animal models.

The platform could support multiple translational applications, including anti-fibrotic drug testing, investigation of hepatocyte plasticity, precision medicine approaches, and validation of therapeutic targets in human liver tissue. As spatial omics and single-cell technologies continue to evolve, extended PCLS culture may become an increasingly valuable bridge between mechanistic discovery and clinical translation.