IL1B and dengue disease: Accordingly, the determination for the expression of intracellular cytokines in dengue-infected monocytes, that is, TNF-α and IL-1β, as unstimulated and LPS-stimulated conditions in the presence of BFA, which prevented the secretion of any intracellular cytokine that had accumulated in the cytoplasm [41], showed that both circulating unstimulated and LPS-stimulated monocytes from DSS patients reduced the IL-1β and TNF-α production less than the other groups.