RESUMO
Tumor microparticles (T-MPs) are considered as a tumor vaccine candidate. Although some studies have analyzed the mechanism of T-MPs as tumor vaccine, we still lack understanding of how T-MPs stimulate a strong anti-tumor immune response. Here, we show that T-MPs induce macrophages to release a key chemotactic factor CCL2, which attracts monocytes to the vaccine injection site and enhances endocytosis of antigen. Monocytes subsequently enter the draining lymph node, and differentiate into monocyte-derived DCs (moDCs), which present tumor antigens to T lymphocytes and deliver a potent anti-tumor immune response. Mechanically, T-MPs activate the cGAS-STING signaling through DNA fragments, and then induce monocytes to upregulate the expression of IRF4, which is a key factor for monocyte differentiation into moDCs. More importantly, monocytes that have endocytosed T-MPs acquire the ability to treat tumors. Collectively, this work might provide novel vaccination strategy for the development of tumor vaccines and facilitate the application of T-MPs for clinic oncotherapy. Supplementary Information: The online version contains supplementary material available at 10.1186/s12645-023-00190-x.
RESUMO
Autism spectrum disorders (ASDs) comprise a number of heterogeneous neurodevelopmental diseases. Recent studies suggest that the abnormal transmission of neural signaling pathways is associated with the pathogenesis of autism. The aim of this study was to identify a link between the Notch signaling pathway and the pathogenesis of autism. In this study, we demonstrated that prenatal exposure to valproic acid (VPA) resulted in autistic-like behaviors in offspring rats and that the expression of the Notch signaling pathway-related molecules Notch1, Jagged1, Notch intracellular domain (NICD) and Hes1 increased in the prefrontal cortex (PFC), hippocampus (HC) and cerebellum (CB) of VPA rats compared to those of controls. However, inhibiting the Notch pathway with (3,5-Difluorophenacetyl)-L-alanyl-S-phenylglycine-2-butyl Ester (Dapt) reduced the overexpression of Notch pathway-related molecules in offspring rats. Notably, Dapt improved autistic-like behaviors in a VPA-exposed rat model of autism. Furthermore, we investigated whether Dapt improved autistic-like behavior in a VPA rat model by regulating autophagy and affecting the morphology of dendritic spines. We found that the expression of the autophagy-related proteins Beclin 1, LC3B and phospho-p62 in the PFC, HC and CB of VPA model rats increased after Notch signal activation and was inhibited by Dapt compared to those of controls. Moreover, postsynaptic density-95 (PSD-95) protein expression also increased significantly compared to that of VPA model rats. The density of dendritic spines decreased in the PFC of VPA rats treated with Dapt compared to that of VPA model rats. Our present results suggest that VPA induces an abnormal activation of the Notch signaling pathway. The inhibition of excessive Notch signaling activation by Dapt can alleviate autistic-like behaviors in VPA rats. Our working model suggests that the Notch signaling pathway participates in the pathogenesis of autism by regulating autophagy and affecting dendritic spine growth. The results of this study may help to elucidate the mechanism underlying autism and provide a potential strategy for treating autism.
