African swine fever virus (ASFV), the aetiological agent of African swine fever (ASF), causes lethal haemorrhagic fever in domestic pigs with high mortality and morbidity and has devastating consequences on the global swine industry. On-site rapid and sensitive detection of ASFV is key to the timely implementation of control. In this study, we developed a rapid, sensitive and instrument-free ASFV detection method based on CRISPR/Cas12a technology and lateral flow detection (named CRISPR/Cas12a-LFD). The limit of detection of CRISPR/Cas12a-LFD is 20 copies of ASFV genomic DNA per reaction, and the detection process can be completed in an hour. The assay showed no cross-reactivity with other swine DNA viruses, and has 100% agreement with real-time PCR detection of ASFV in 149 clinical samples. Overall, the CRISPR/Cas12a-LFD method provides a novel alternative for the portable, simple, sensitive, and specific detection of ASFV and may contribute to the prevention and control of ASF outbreaks.

Antibodies against programmed cell death protein 1 (PD-1) and its ligand (PD-L1) have dramatically changed the landscape of therapies for non-small cell lung carcinoma (NSCLC); however, the majority of patients do not respond to these agents. In addition, hyperprogressive disease (HPD) develops in a larger portion of NSCLC patients treated with PD-1/PD-L1 inhibitors than in patients treated with standard chemotherapy. The use of chimeric antigen receptor (CAR) T cells has been successful to treat blood cancers but not for solid tumors like NSCLC. In this work, we constructed CAR T cells that target PD-L1 and evaluated their efficacy in NSCLC with either high or low PD-L1 expression. PD-L1-CAR T cells exhibited antigen-specific activation, cytokine production, and cytotoxic activity against PD-L1^high NSCLC cells and xenograft tumors. Furthermore, the addition of a subtherapeutic dose of local radiotherapy improved the efficacy of PD-L1-CAR T cells against PD-L1^low NSCLC cells and tumors. Our findings indicate that PD-L1-CAR T cells represent a novel therapeutic strategy for patients with PD-L1-positive NSCLC, particularly for those who are susceptible to HPD.

Our previous report demonstrated that genetic ablation of miR-301a reduces Kras-driven lung tumorigenesis in mice. However, the impact of miR-301a on host anti-tumor immunity remains unexplored. Here we assessed the underlying molecular mechanisms of miR-301a in the tumor microenvironment. The differentially expressed genes were identified by using deep sequencing. The immune cell counts, and cytokines expression were analyzed by realtime PCR, immunohistochemistry and flow cytometry. The role of miR-301a/Runx3 in lung tumor was evaluated on cell growth, migration and invasion. The function of miR-301a/Runx3 in regulating tumor microenvironment and tumor metastasis were evaluated in Kras transgenic mice and B16/LLC1 syngeneic xenografts tumor models. In this work, we identified 1166 up-regulated and 475 down-regulated differentially expressed genes in lung tumor tissues between KrasLA2 and miR-301a−/−; KrasLA2 mice. Immune response and cell cycle were major pathways involved in the protective role of miR-301a deletion in lung tumorigenesis. Overexpression of the miR-301a target, Runx3, was an early event identified in miR-301a−/−; KrasLA2 mice compared to WT-KrasLA2 mice. We found that miR-301a deletion enhanced CD8+ T cell accumulation and IFN-γ production in the tumor microenvironment and mediated antitumor immunity. Further studies revealed that miR-301a deficiency in the tumor microenvironment effectively reduced tumor metastasis by elevating Runx3 and recruiting CD8+ T cells, whereas miR-301a knockdown in tumor cells themselves restrained cell migration by elevating Runx3 expression. Our findings further underscore that miR-301a facilitates tumor microenvironment antitumor immunity by Runx3 suppression in lung tumorigenesis.

CAR T cell therapy has been successfully used in the treatment of hematological malignancies, and the strategy that deletion of inhibitory receptor on the CAR T cell surface, such as PD-1, greatly enhance the antitumor effects. Here, we describe a one-step electroporation for the co-transfection of Cas9:sgRNA and CAR plasmids on primary T cells to demonstrate the effect of SHP-1 deletion in CAR T cells. By using PiggyBac Transposase system, we can achieve more than 90% of T cells express CAR gene and nearly 60% SHP-1 knockout efficiency in T cells. We show that knockout of SHP-1 in CD133 CAR T cells resulted in significantly improve the cytolysis effect on CD133 positive glioma cell lines. We further demonstrate that the enhanced antitumor efficacy of SHP-1 deletion is due to the increased release of TNF-α, IL-2 and IFN-γ in vitro. Finally, we evaluated the biosafety of Cas9 genome editing and did not find any insertions of Cas9 and obvious editing in off-target sites in CAR T cells. These data provide an approach for achieving both intracellular inhibitory molecule, SHP-1 deletion and CD133 CAR gene over-expression in human T cells. And SHP-1 could be a new potential target for adoptive CAR T cells immunotherapy.

(1) Background: the miR-301a is well known involving the proliferation and migration of tumor cells. However, the role of miR-301a in the migration and phagocytosis of macrophages is still unclear. (2) Methods: sciatic nerve injury, liver injury models, as well as primary macrophage cultures were prepared from the miR-301a knockout (KO) and wild type (WT) mice to assess the macrophage’s migration and phagocytosis capabilities. Targetscan database analysis, Western blotting, siRNA transfection, and CXCR4 inhibition or activation were performed to reveal miR301a’s potential mechanism. (3) Results: the macrophage’s migration and phagocytosis were significantly attenuated by the miR-301a KO both in vivo and in vitro. MiR-301a can target Yin-Yang 1 (YY1), and miR-301a KO resulted in YY1 up-regulation and CXCR4 (YY1′s down-stream molecule) down-regulation. siYY1 increased the expression of CXCR4 and enhanced migration and phagocytosis in KO macrophages. Meanwhile, a CXCR4 inhibitor or agonist could attenuate or accelerate, respectively, the macrophage migration and phagocytosis. (4) Conclusions: current findings indicated that miR-301a plays important roles in a macrophage’s capabilities of migration and phagocytosis through the YY1/CXCR4 pathway. Hence, miR-301a might be a promising therapeutic candidate for inflammatory diseases by adjusting macrophage bio-functions.

Background: Tenascin-C (TNC) is an extracellular matrix (ECM) protein involved in tissue damage and fibrosis. Chimeric antigen receptor (CAR) cell therapy is a novel therapeutic approach that has attracted increasing attention in recent years. Here, we engineered CAR-macrophages targeting TNC (TNC-CAR-Ms) and explored the underlying mechanism through which TNC-CAR-Ms treat liver fibrosis. Methods: The role of TNC in liver fibrosis was studied in established Tnc knockout (KO) and littermate control mice. A TNC-targeted single-chain variable fragment (scFv) was designed to generate TNC-CAR-Ms and evaluate their biological function. The phagocytosis and killing effects of TNC-CAR-Ms were tested in vitro, while the antifibrotic efficacy and safety of TNC-CAR-Ms were evaluated in vivo. The underlying mechanism through which TNC-CAR-Ms treat liver fibrosis was investigated by Western blotting, flow cytometry, and RNA sequencing. Results: TNC expression was significantly upregulated in the liver and activated hepatic stellate cells (HSCs) in carbon tetrachloride (CCl ₄ )-treated mice. Animal studies showed that Tnc KO protects mice from CCl ₄ -induced liver damage and fibrosis. Upon demonstrating their ability to engulf and kill activated HSCs, we intravenously administered TNC-CAR-Ms to fibrotic mice and found that TNC-CAR-Ms significantly reduced liver fibrosis. Mechanistically, TNC-CAR-Ms specifically migrated to liver tissues, potently reduced TNC expression, and decreased the activity of the Toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB) and integrin/focal adhesion kinase (FAK) signaling pathway. In addition, TNC-CAR-Ms significantly modified the hepatic immune microenvironment, characterized mainly by an increase in the numbers of M2-polarized macrophages and CD8 ⁺ T cells in the liver. Finally, in CCl ₄ -treated mice, the depletion of CD8 ⁺ T cells with an anti-CD8α antibody significantly impaired the antifibrotic effect of TNC-CAR-Ms. Conclusions: Our proof-of-concept study demonstrates the therapeutic potential of TNC-CAR-Ms in alleviating liver fibrosis and may inform the development of future therapeutic strategies for the treatment of a range of liver diseases with a fibrotic phenotype.