While our results indicate that a small portion of IL-1β can be found in dead cells (2000 g pellet), microvesicles (10,000 g pellet) and exosomes (100,000 g pellet) after infection (39), the vesicular release patterns induced by the two strains and the low total levels present in vesicles excludes differential release of IL-1β by vesicular transport (Figure 4E). Here, IL1B is linked to infection.