Characterization of conditions for the primary culture of human small intestinal epithelial cells.

Intestinal epithelial cells (IECs) are important for many aspects of gut physiology and pathology. Different approaches have been tried for the primary culture of human IECs, with varying degrees of success, as apoptosis easily occurs. Our aim was to develop a method for primary culture of human IECs from biopsy material. IECs and Lamina propria (LP) cells were liberated from duodenal biopsies obtained from subjects undergoing routine endoscopy for clinical investigations, whose small bowel was macroscopically normal. IECs were cultured on collagen membranes in a 12-well tissue culture cluster, with LP cells and allogeneic Epstein-Barr Virus (EBV)-transformed B lymphocytes (allo-B cells) underneath, in the well. Cultured IECs were characterized by light and confocal microscopy. Cytokine levels in culture supernatants were measured by ELISA. Cells showed the columnar morphology of IECs, even after several days in culture. Best results were obtained from IECs cultured above both LP and allo-B cells. IECs did not form monolayers as do transformed epithelial cell lines, but they did preserve their original cell-cell contacts. Analysis of culture supernatants showed that IL-10 was produced by IECs initially, but IL-1ra was produced by LP cells in the underlying wells with increasing time in culture. Very little IL-1 beta was produced from any cultures. These results show that IECs can be isolated and maintained in primary culture for a short while, which could open new possibilities for research using patient material instead of cell lines.