Evidence for the involvement of NOD2 in regulating colonic epithelial cell growth and survival

Figure 4 Decreased survival of Nod2^-/- CECs in vitro. A: The level of apoptotic cells in cultures of primary CECs from Nod2^+/+ and Nod2^-/- mice was determined by annexin V and propidium iodide (PI) staining and flow cytometry. Data was collected from 5 experiments and shows the mean (± SE) values. ^cP < 0.01 B: The frequency of Nod2^+/+ and Nod2^-/- CECs containing caspase3 activity was determined using the flow cytometry based NucViewTM488 Caspase-3 assay. The data represents the mean (± SE) values collected from two experiments. C: The growth of Nod2^+/+ and Nod2^-/- CECs in the absence (Media) or presence of 10 μg/mL muramyl dipeptide (MDP) was determined by comparing the number of viable CEC at the initiation of culture and after 24 h and 48 h. The data shown represents the mean (± SE) of 3 experiments. ^aP < 0.05, ^bP < 0.001. D: NF-κB activation in Nod2^+/+ (filled bars) and Nod2^-/- (open bars) CEC after exposure to muramyl dipeptide (MDP) was determined by quantitating NF-κB p65 levels in nuclear extracts using a Transfactor Kit as described in Methods section. Values were normalized to control values of cells grown in media alone. The data shown represents the mean (± SE) values from 3 independent experiments.