Elevation of IL-8 secretion induced by PEDV infection via NF-κB signaling pathway.

Porcine epidemic diarrhea virus (PEDV) is associated with severe enteritis, which contributes to high mortality in piglets. The aim of this study was to describe molecular mechanisms associated with proinflammatory cytokine(s) production during PEDV infection. We showed that infection of porcine intestine epithelial cell clone J2 (IPEC-J2) with PEDV induces a gradual increase in interleukin 8 (IL-8) production at different time points, as well as infection of Vero E6 with PEDV. The secretion of IL-8 in these two cell lines infected with PEDV is related to the activation of NF-κB. Furthermore, the cells expressing PEDV M or E protein can induce the upregulation of IL-8. These findings suggest that the IL-8 production can be the initiator of inflammatory response by the host cells upon PEDV infection.

Tanshinone IIA induces ER stress and JNK activation to inhibit tumor growth and enhance anti-PD-1 immunotherapy in non-small cell lung cancer.

BACKGROUND: Non-small cell lung cancer (NSCLC) remains at the forefront of new cancer cases, and there is an urgent need to find new treatments or improve the efficacy of existing therapies. In addition to the application in the field of cerebrovascular diseases, recent studies have revealed that tanshinone IIA (Tan IIA) has anticancer activity in a variety of cancers. PURPOSE: To investigate the potential anticancer mechanism of Tan IIA and its impact on immunotherapy in NSCLC. METHODS: Cytotoxicity and colony formation assays were used to detect the Tan IIA inhibitory effect on NSCLC cells. This research clarified the mechanisms of Tan IIA in anti-tumor and programmed death-ligand 1 (PD-L1) regulation by using flow cytometry, transient transfection, western blotting and immunohistochemistry (IHC) methods. Besides, IHC was also used to analyze the nuclear factor of activated T cells 1 (NFAT2) expression in NSCLC clinical samples. Two animal models including xenograft mouse model and Lewis lung cancer model were used for evaluating tumor suppressive efficacy of Tan IIA. We also tested the efficacy of Tan IIA combined with programmed cell death protein 1 (PD-1) inhibitors in Lewis lung cancer model. RESULTS: Tan IIA exhibited good NSCLC inhibitory effect which was accompanied by endoplasmic reticulum (ER) stress response and increasing Ca2+ levels. Moreover, Tan IIA could suppress the NFAT2/ Myc proto oncogene protein (c-Myc) signaling, and it also was able to control the Jun Proto-Oncogene(c-Jun)/PD-L1 axis in NSCLC cells through the c-Jun N-terminal kinase (JNK) pathway. High NFAT2 levels were potential factors for poor prognosis in NSCLC patients. Finally, animal experiments data showed a stronger immune activation phenotype, when we performed treatment of Tan IIA combined with PD-1 monoclonal antibody. CONCLUSION: The findings of our research suggested a novel mechanism for Tan IIA to inhibit NSCLC, which could exert anti-cancer effects through the JNK/NFAT2/c-Myc pathway. Furthermore, Tan IIA could regulate tumor PD-L1 levels and has the potential to improve the efficacy of PD-1 inhibitors.

Broad antagonism of coronaviruses nsp5 to evade the host antiviral responses by cleaving POLDIP3.

Coronaviruses (CoVs) are a family of the largest RNA viruses that typically cause respiratory, enteric, and hepatic diseases in animals and humans, imposing great threats to the public safety and animal health. Porcine deltacoronavirus (PDCoV), a newly emerging enteropathogenic coronavirus, causes severe diarrhea in suckling piglets all over the world and poses potential risks of cross-species transmission. Here, we use PDCoV as a model of CoVs to illustrate the reciprocal regulation between CoVs infection and host antiviral responses. In this study, downregulation of DNA polymerase delta interacting protein 3 (POLDIP3) was confirmed in PDCoV infected IPEC-J2 cells by isobaric tags for relative and absolute quantification (iTRAQ) and Western blotting analysis. Overexpression of POLDIP3 inhibits PDCoV infection, whereas POLDIP3 knockout (POLDIP3-/-) by CRISPR-Cas9 editing significantly promotes PDCoV infection, indicating POLDIP3 as a novel antiviral regulator against PDCoV infection. Surprisingly, an antagonistic strategy was revealed that PDCoV encoded nonstructural protein 5 (nsp5) was responsible for POLDIP3 reduction via its 3C-like protease cleavage of POLDIP3 at the glutamine acid 176 (Q176), facilitating PDCoV infection due to the loss of antiviral effects of the cleaved fragments. Consistent with the obtained data in IPEC-J2 cell model in vitro, POLDIP3 reduction by cleavage was also corroborated in PDCoV infected-SPF piglets in vivo. Collectively, we unveiled a new antagonistic strategy evolved by PDCoV to counteract antiviral innate immunity by nsp5-mediated POLDIP3 cleavage, eventually ensuring productive virus replication. Importantly, we further demonstrated that nsp5s from PEDV and TGEV harbor the conserved function to cleave porcine POLDIP3 at the Q176 to despair POLDIP3-mediated antiviral effects. In addition, nsp5 from SARS-CoV-2 also cleaves human POLDIP3. Therefore, we speculate that coronaviruses employ similar POLDIP3 cleavage mechanisms mediated by nsp5 to antagonize the host antiviral responses to sustain efficient virus infection.

Andrographolide suppresses non-small-cell lung cancer progression through induction of autophagy and antitumor immune response.

Despite recent advances in diagnosis and therapeutic strategies, treatment of non-small-cell lung cancer (NSCLC) remains unsatisfactory in terms of prognosis. Andrographolide (AD), a principal active component of Andrographis paniculata (Burm.f.) Nees, exerts anti-cancer therapeutic properties. AD has been used for centuries in China for clinical treatment of viral infections. However, the pharmacological biology of AD in NSCLC remains unknown. In this study, AD regulated autophagy and PD-L1 expression in NSCLC. Molecular dynamics simulations indicated that AD bound directly to signal transducer and activator of transcription-3 (STAT3) with high affinity. Proteomics analysis indicated that AD reduced the expression of tumour PD-L1 in NSCLC by suppressing JAK2/STAT3 signalling. AD modulated the P62-dependent selective autophagic degradation of PD-L1 by inhibiting STAT3 phosphorylation. In vivo study revealed that AD suppressed tumour growth in H1975 xenograft mice and Lewis lung carcinoma cell models, and better efficacy was obtained at higher concentrations. AD prolonged the survival time of the mice and enhanced the treatment efficacy of anti-PD-1 mAb immunotherapy by stimulating CD8+ T cell infiltration and function. This work elucidated the specific mechanism by which AD inhibited NSCLC. Treatment with the combination of AD and anti-PD-1 mAb immunotherapy could be a potential strategy for patients with NSCLC.

Aircraft Detection for Remote Sensing Image Based on Bidirectional and Dense Feature Fusion.

Aircraft, as one of the indispensable transport tools, plays an important role in military activities. Therefore, it is a significant task to locate the aircrafts in the remote sensing images. However, the current object detection methods cause a series of problems when applied to the aircraft detection for the remote sensing image, for instance, the problems of low rate of detection accuracy and high rate of missed detection. To address the problems of low rate of detection accuracy and high rate of missed detection, an object detection method for remote sensing image based on bidirectional and dense feature fusion is proposed to detect aircraft targets in sophisticated environments. On the fundamental of the YOLOv3 detection framework, this method adds a feature fusion module to enrich the details of the feature map by mixing the shallow features with the deep features together. Experimental results on the RSOD-DataSet and NWPU-DataSet indicate that the new method raised in the article is capable of improving the problems of low rate of detection accuracy and high rate of missed detection. Meanwhile, the AP for the aircraft increases by 1.57% compared with YOLOv3.

Vehicle Detection in Remote Sensing Image Based on Machine Vision.

Target detection in remote sensing images is very challenging research. Followed by the recent development of deep learning, the target detection algorithm has obtained large and fast growth. However, in the application of remote sensing images, due to the small target, wide range, small texture, and complex background, the existing target detection methods cannot achieve people's hope. In this paper, a target detection algorithm named IR-PANet for remote sensing images of an automobile is proposed. In the backbone network CSPDarknet53, SPP is used to strengthen the learning content. Then, IR-PANet is used as the neck network. After the upper sampling, depthwise separable convolution is used to greatly avoid the lack of small target feature information in the convolution of the shallow network and increase the semantic information in the high-level network. Finally, Gamma correction is used to preprocess the image before image training, which effectively reduces the interference of shadow and other factors on training. The experiment proves that the method has a better effect on small targets obscured by shadows and under the color similar to the background of the picture, and the accuracy is significantly improved based on the original algorithm.