To examine caspase-1 activation and subsequent signalling pathways by environmental or clinical isolates of Burkholderia, wild-type bone marrow-derived macrophages (BMM) were infected with B. pseudomallei strains E8, E212, K96243 and 1026b as well as B. thailandensis strain E264 at multiplicity of infection (MOI) of 50 and 200, respectively. Here, CASP1 is linked to infection.