A) RAW cells were pre-treated with 500 µg/mL TUDCA, and then infected with 100 MOI Brucella (B. mel) for 30 min., washed, and incubated 24 h prior to harvesting for RNA analysis by qPCR. Results were combined from 3–4 independent experiments by normalization to B. melitensis induced UPR gene expression ( = 100%), *p≤0.04 and p = 0.00003 vs. B. melitensis infection and NS vs. uninfected. For XBP1s and ERdj4, N = 2 independent experiments. B) RAW cells were not treated (black circles) or pre-treated with TUDCA (gray squares), infected as in (A), and lysed at different times following infection. CFU (colony forming units) were determined by transfer to dilution plates. *P≤0.04. Similar results were obtained with 10 MOI Brucella (not shown). Results are representative of 6 independent experiments. C) D17 osteosarcoma cells were untreated (left) or pre-treated with 500 µg/mL TUDCA (right), infected with Brucella-YFP (green) for 24 h, fixed, and stained with anti-calreticulin (red).