Ruxolitinib-loaded cytokine nanosponge alleviated the cytokine storm and dampened macrophage overactivation for the treatment of hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening clinical syndrome characterized by a positive feedback loop between cytokine storm and macrophages and lymphocytes overactivation, which could serve as a valid therapeutic target for HLH treatment. In this study, the clinically extensively used JAK1/2 inhibitor ruxolitinib was encapsulated into macrophage membrane-coated nanoparticles (M@NP-R) with high drug-loading efficiency for targeted HLH treatment. In vitro and in vivo studies demonstrated that M@NP-R not only efficiently adsorbed extracellular proinflammation cytokines, like IFN-γ and IL-6 to alleviate the cytokine storm, but also effectively dampened macrophage activation and proliferation by intracellular JAK/STAT signaling pathway inhibition. M@NP-R treatment significantly ameliorated the clinical and laboratory manifestations of HLH in mouse models, including trilineage cytopenia, hypercytokinemia, organomegaly, hepatorenal dysfunction, and tissue inflammation. Importantly, M@NP-R significantly enhanced the survival of the lethal HLH mice. Altogether, M@NP-R successfully blocked the positive feedback loop between the cytokine storm and macrophage overactivation by depleting extracellular inflammatory cytokines and inhibiting the intracellular JAK/STAT signaling pathway, both of which worked synergistically in HLH treatment. As ruxolitinib has already been extensively used in clinics with favorable safety, and M@NP is biodegradable and highly biocompatible, M@NP-R has good prospects for clinical translation.