Caspase-2 Mediated Apoptotic and Necrotic Murine Macrophage Cell Death Induced by Rough Brucella abortus
(A) RB51 and RA1 induced 61.5%±8.7% and 74.7%±5.6% macrophage cells death, respectively, at a MOI of 200 at 24 h post infection. B. abortus strain 2308 induced limited macrophage cell death even at the MOI of 2,000. (B) LDH release from RB51, RA1 and S2308 infected macrophages. The data represent the means±standard deviations for three independent experiments. The asterisk (*) represents the significant differences (P<0.05) of the LDH release level from macrophages infected by smooth S2308 compared to that from macrophages infected with rough strain RB51 or RA1. (C) Growth kinetics of RB51, RA1 and S2308 in macrophages. The number of internalized cells of S2308 at MOI 2,000 found was similar to the number of cells of internalized RB51 and RA1 at a MOI 200 at 1 h post infection. The asterisk (*) represents the significant differences (P<0.05) in survival level of smooth S2308 compared to that of rough strain RB51 or RA1 inside infected macrophages.