Ex-vivo evaluation of gene therapy vectors in human pancreatic (cancer) tissue slices.

AIM: To culture human pancreatic tissue obtained from small resection specimens as a pre-clinical model for examining virus-host interactions.
METHODS: Human pancreatic tissue samples (malignant and normal) were obtained from surgical specimens and processed immediately to tissue slices. Tissue slices were cultured ex vivo for 1-6 d in an incubator using 95% O(2). Slices were subsequently analyzed for viability and morphology. In addition the slices were incubated with different viral vectors expressing the reporter genes GFP or DsRed. Expression of these reporter genes was measured at 72 h after infection.
RESULTS: With the Krumdieck tissue slicer, uniform slices could be generated from pancreatic tissue but only upon embedding the tissue in 3% low melting agarose. Immunohistological examination showed the presence of all pancreatic cell types. Pancreatic normal and cancer tissue slices could be cultured for up to 6 d, while retaining viability and a moderate to good morphology. Reporter gene expression indicated that the slices could be infected and transduced efficiently by adenoviral vectors and by adeno associated viral vectors, whereas transduction with lentiviral vectors was limited. For the adenoviral vector, the transduction seemed limited to the peripheral layers of the explants.
CONCLUSION: The presented system allows reproducible processing of minimal amounts of pancreatic tissue into slices uniform in size, suitable for pre-clinical evaluation of gene therapy vectors.