Immunotoxicity of XXXX nanoparticles with different size and electrostatic charge.

@entity137 @entity39 @entity19 @entity5 @entity1947 @entity1618 @entity1961 @entity842 @entity1948
While @entity1947 ( @entity1948 ) nanoparticles (NPs) have been recognized to have promising applications in biomedicine, their immunotoxicity has been inconsistent and even contradictory. To address this issue, we investigated whether @entity1948 NPs with different size (20 or 100 nm) and electrostatic charge (positive or negative) would cause immunotoxicity in vitro and in vivo, and explored their underlying molecular mechanism. Using Raw 264.7 cell line, we examined the immunotoxicity mechanism of @entity1948 NPs as cell viability. We found that in a cell viability assay, @entity1948 NPs with different size and charge could induce differential @entity137 to Raw 264.7 cells. Specifically, the positively charged @entity1948 NPs exerted higher @entity137 than the negatively charged ones. Next, to gauge systemic immunotoxicity, we assessed immune responses of C57BL/6 @entity19 after oral administration of 750 mg/kg/day dose of @entity1948 NPs for 2 weeks. In parallel, @entity1948 NPs did not alter the cell-mediated immune response in @entity19 but suppressed innate immunity such as natural killer cell activity. The @entity1961 (+)/CD8(+) ratio, a marker for matured T-cells was slightly reduced, which implies the alteration of immune status induced by @entity1948 NPs. Accordingly, @entity842 production from splenocyte culture supernatant in @entity1948 NP-fed @entity19 was lower than control. Consistently, serum levels of pro/anti-inflammatory (interleukin [IL]-1b, @entity5 @entity39 factor-a, and @entity1618 ) and T helper-1 cytokines (interferon-y and IL-12p70) in @entity1948 NP-fed @entity19 were significantly suppressed. Collectively, our results indicate that different sized and charged @entity1948 NPs would cause in vitro and in vivo immunotoxicity, of which nature is an immunosuppression.
