GBP2 and escherichia coli infection: We found that GBP2−/− BMDMs mimicked GBPchr3−/− BMDMs in their unresponsiveness to E. coli infections, as measured by LDH release as a marker of cell death (Fig. 3A) and secretion of IL-1β (Fig. 3B) and IL-18 (Fig. 3C).