T84 cells (human colon carcinoma epithelial cell line) were seeded in 24-well tissue culture plates (BD Biosciences, San Jose, CA) at a density of 1610 6 cells/well and grown until they reached 90 to 95% confluence. L. plantarum cells were killed by exposure to UV light for 1 h and the lack of cell viability was confirmed by culture in MRS agar. T84 cells were co-cultured with UV-killed recombinant L. plantarum at a MOI 10:1 bacteria per cell, for 48 h. L. plantarum control and 0.5 mg/ml TNFa were used as negative and positive controls, respectively. Supernatants were collected and the human IL-8 production was measured by ELISA (Quantikine, R&D Systems, Minneapolis, MN).