The Yersinia pestis Effector YopM Inhibits Pyrin Inflammasome Activation
Fig 5
YopM maintains an inhibitory phenotype in human PBMCs, and in a human THP-1 cell line overexpressing YFP-Pyrin.
Co-IP pulldown in these cells as well as mouse BMDMs indicate YopM interaction with Pyrin, Rsk1, Pkn1, and Iqgap1. A) PBMCs were isolated from healthy human donor blood and infected at MOI 10 with indicated Y. pestis strains without priming. At 6 hours p.i. supernatant was collected for IL-1β detection by ELISA. B) Cultured YFP-Pyrin THP-1 cells were differentiated with 100nM Vitamin D3 for 48–72 hours, and infected with indicated Y. pestis strains at MOI 10. Shown is IL-1β assayed from supernatants by ELISA at 6 hrs p.i. Figures are representative of three or more experiments. Shown is mean plus s.d. for triplicate wells. * p<0.05, **p<0.01, ***p<0.001. C-D) Shown are Western blot results of co-IP with anti-YopM using C) Vitamin D3-differentiated, unprimed YFP-Pyrin cells or D) LPS-primed BMDMs after infection with the indicated strains at MOI 10 for 3 hours. Bead-bound protein and lysates were separated by SDS-PAGE and analyzed by Western Blot for the proteins indicated.