A MICROFLUIDIC DEVICE FOR LONG-TERM MAINTENANCE OF ORGANOTYPIC LIVER CULTURES

Abstract

Liver cultures may be used for modeling disease progression, testing therapies and predicting drug induced liver injury. The complexity of the liver cultures has evolved over the years from monocultures of hepatocytes to co-cultures with non-parenchymal cells and finally to precision cut liver slices. The latter culture format retains biomolecular and cellular complexity of the native liver and therefore holds considerable promise for in vitro testing. However, liver slices remain functional for ~72 h in vitro and hold only limited utility for some of the disease modeling and therapy testing applications that require longer culture times. This paper describes a microfluidic device for longer-term maintenance of functional organotypic liver cultures. Our microfluidic culture system was designed to enable direct injection of liver tissue into a culture chamber through a valve-enabled side port. Liver tissue was embedded in collagen and remained functional for up to 31 days as highlighted by continued production of albumin. These organotypic cultures also produced bile and urea and expressed several enzymes involved in metabolism of xenobiotics. In contrast, matched liver tissue embedded in collagen and cultured in the same media in a 96-well plate lost its phenotype and function on the timescale of 3 to 5 days. The microfluidic organotypic liver cultures described here represent a significant advance in liver cultivation and may be used in the future for modeling liver diseases or for individualized selection of liver-directed therapies.