Decellularized matrix (dc-matrix) derived from PP-<i>Sgg</i>-treated cells is sufficient to stimulate cell proliferation.

A. HT29 cells and COL6A1 stable knockdown HT29 cells were co-cultured with Sgg strain TX20005, L. lactis or media only for 12 hours. The wells were incubated with antibiotics to eliminate bacteria followed by washing. Cells were then stripped away from the underlying matrix as described in the Materials and Methods section. HT29 cells (~ 1 x 104) that had not been previously exposed to Sgg were seeded on the indicated dc-matrices and incubated for 24 hours. Viable cells were counted. B and C. HT29 (B) and HCT116 (C) cells were transiently transfected with control siRNA or COL6A1 siRNA and then co-cultured with Sgg TX20005, TX20008 or media only. Dc-matrices were then prepared. Fresh HT29 and HCT116 cells that had not been previously exposed to Sgg were seeded onto the indicated dc-matrices and incubated for 24 hours. Cell proliferation was examined using the CCK-8 assay. Each experiment was repeated at least three times. Data is presented as the mean ± SEM. Statistical analysis was done using unpaired, two-tailed t test. **, p p < 0.0001.