(A) HL60 cells were infected with the indicated opsonized bacterial strains and ROS production in the presence (+) or absence (-) of EGTA and magnesium (Mg2+) was monitored over time using chemiluminescence.
(B) The indicated serum dilutions were applied to a dot blot to detect the presence of IgM using anti-human IgM antibody (α-IgM).
(C) HL60 cells were infected with the indicated bacterial strains opsonized with IgG-depleted serum or IgM-depleted serum and ROS production monitored over time using chemiluminescence.
(A and C) Chemiluminescence was quantified from three independent experiments at the indicated time point after infection. Bars represent means ± standard error.
Mock, mock infection; NS, not statistically significantly different; RLU, relative luminescence units; wt, wild-type. *p < 0.05; **p < 0.001.