FIG 3.

Caspase-1 of BMDMs is activated during E. tarda infection. (A) Effect of the caspase-1 inhibitor Ac-YVAD-AOM on the release of LDH. BMDMs were pretreated with 317 μM Ac-YVAD-AOM or dimethyl sulfoxide (DMSO) for 90 min and then infected with the wild type for 2 h. Culture supernatants were collected to determine LDH release. ***, P < 0.001. (B) E. tarda-induced activation of caspase-1. BMDMs were either mock infected or infected with indicated strains for 2 h. Cell culture supernatants were collected, and cell monolayers were lysed with 4× SDS sample buffer. Membrane was probed with anti-caspase-1 (p20) mouse monoclonal antibody. β-Actin was used to show the same loading of the cell lysates.