Genetic deletion of the Rho GEF Net1 impairs mouse macrophage motility and actin cytoskeletal organization

Specific knockout of macrophage SHP2 promotes macrophage M2 polarization and alleviates renal ischemia-reperfusion injury

To investigate the effect of specific knockout of SHP2 in mononuclear macrophages on renal ischemia-reperfusion injury and its molecular mechanism. The structural, functional, and pathological changes in the mouse kidney were detected by ultrasound testing. The relative fluorescence intensity of α-SMA, Col1, Col3, and Vim was measured by immunofluorescence staining, and ELISA was performed to detect the concentrations of blood urea nitrogen (BUN), creatinine (Crea), and uric acid (UA). The relative protein expressions of relevant proteins in the mouse kidney tissue were detected by western blotting. Specific knockout of SHP2 could improve both renal function and structure, reduce the relative fluorescence intensity of α-SMA, Col1, Col3 and Vim, lower the concentrations of BUN, Crea, and UA and the expressions of TNF-α, IFNγ, p-NFκB, and p-MyD88, and increase the expressions of p-MerTK, p-FAK, p-PI3K, and p-IκB. The above results illustrate that specific knockdown of macrophage SHP2 promotes macrophage M2 polarization and alleviates renal ischemia-reperfusion injury. The above results illustrate that specific knockdown of macrophage SHP2 promotes macrophage M2 polarization and attenuatesll renal ischemia-reperfusion injury. Specific knockout of macrophage SHP2 promotes macrophage M2 polarization and alleviates renal ischemia-reperfusion injury.

Transcriptomic Responses to Koi Herpesvirus in Isolated Blood Leukocytes from Infected Common Carp

Koi herpesvirus (KHV, CyHV-3) causes severe economic losses in carp farms. Its eradication is challenging due to the establishment of latency in blood leukocytes and other tissues. To understand the molecular mechanisms leading to KHV infection in leukocytes, common carp were bath-exposed to KHV at 17 °C. After confirming the presence of viral transcripts in blood leukocytes at ten days post infection, RNA-Seq was performed on peripheral blood leukocytes on the Illumina NovaSeq. KHV infection triggered a robust immune response mediated by pattern recognition receptors, mainly toll-like receptors (tlr2, tlr5, tlr7, and tlr13), urokinase plasminogen activator surface receptor-like, galectin proteins, and lipid mediators such as leukotriene B4 receptor 1. Enriched pathways showed increased mitochondria oxidative phosphorylation and the activation of signalling pathways such as mitogen-activated protein kinases (MAPKs) and vascular endothelial growth factor (VEGF). KHV-infected leukocytes showed low production of reactive oxygen species (ROS) and glutathione metabolism, high iron export and phagocytosis activity, and low autophagy. Macrophage polarization was deduced from the up-regulation of genes such as arginase non-hepatic 1-like, macrophage mannose receptor-1, crem, il-10, and il-13 receptors, while markers for cytotoxic T cells were observed to be down-regulated. Further work is required to characterise these leukocyte subsets and the molecular events leading to KHV latency in blood leukocytes.

Macrophages-Related Genes Biomarkers in the Deterioration of Atherosclerosis

Background

The macrophages are involved in all stages of cardiovascular diseases, demonstrating the correlation between inflammation, atherosclerosis, and myocardial infarction (MI). Here, we aim to investigate macrophages-related genes in the deterioration of atherosclerosis.

Methods

GSE41571 was downloaded and the abundance of immune cells was estimated by utilizing the xCell. By utilizing the limma test and correlation analysis, differentially expressed macrophages-related genes (DEMRGs) were documented. The functional pathways and the protein–protein interaction (PPI) network were analyzed and the hub DEMRGs were obtained. The hub DEMRGs and their interactions were analyzed using NetworkAnalyst 3.0 and for validation, the expressions of hub DEMRGs were analyzed using the GSE135055 and GSE116250 datasets as well as atherosclerosis and MI mice model.

Results

A total of 509 differentially expressed genes (DEGs) were correlated with the abundance of macrophages and were identified as DEMRGs (Pearson correlation coefficients (PCC) > 0.6), which were mainly enriched in extracellular structure organization, lysosomal membrane, MHC protein complex binding, and so on. After screening out, 28 hub DEMRGs were obtained with degrees ≥20, including GNAI1 (degree = 113), MRPS2 (degree = 56), HCK (degree = 45), SOCS3 (degree = 40), NET1 (degree = 28), and so on. After validating using Gene Expression Omnibus (GEO) datasets and the atherosclerosis and MI mice model, eight proteins were validated using ApoE-/- and C57 mice. The expression levels of proteins, including SYNJ2, NET1, FZD7, LCP2, HCK, GNB2, and PPP4C were positively correlated to left ventricular ejection fraction (LVEF), while that of EIF4EBP1 was negatively correlated to LVEF.

Conclusion

The screened hub DEMRGs, SYNJ2, NET1, FZD7, LCP2, HCK, GNB2, EIF4EBP1, and PPP4C, may be therapeutic targets for treatment and prediction in the patients with plaque progression and MI recurrent events. The kit of the eight hub DEMRGs may test plaque progression and MI recurrent events and help in the diagnosis and treatment of MI-induced heart failure (HF), thus decreasing mortality and morbidity.

High-throughput analysis of lung immune cells in a combined murine model of agriculture dust-triggered airway inflammation with rheumatoid arthritis

Rheumatoid arthritis (RA)-associated lung disease is a leading cause of mortality in RA, yet the mechanisms linking lung disease and RA remain unknown. Using an established murine model of RA-associated lung disease combining collagen-induced arthritis (CIA) with organic dust extract (ODE)-induced airway inflammation, differences among lung immune cell populations were analyzed by single cell RNA-sequencing. Additionally, four lung myeloid-derived immune cell populations including macrophages, monocytes/macrophages, monocytes, and neutrophils were isolated by fluorescence cell sorting and gene expression was determined by NanoString analysis. Unsupervised clustering revealed 14 discrete clusters among Sham, CIA, ODE, and CIA+ODE treatment groups: 3 neutrophils (inflammatory, resident/transitional, autoreactive/suppressor), 5 macrophages (airspace, differentiating/recruited, recruited, resident/interstitial, and proliferative airspace), 2 T-cells (differentiating and effector), and a single cluster each of inflammatory monocytes, dendritic cells, B-cells and natural killer cells. Inflammatory monocytes, autoreactive/suppressor neutrophils, and recruited/differentiating macrophages were predominant with arthritis induction (CIA and CIA+ODE). By specific lung cell isolation, several interferon-related and autoimmune genes were disproportionately expressed among CIA and CIA+ODE (e.g. Oasl1, Oas2, Ifit3, Gbp2, Ifi44, and Zbp1), corresponding to RA and RA-associated lung disease. Monocytic myeloid-derived suppressor cells were reduced, while complement genes (e.g. C1s1 and Cfb) were uniquely increased in CIA+ODE mice across cell populations. Recruited and inflammatory macrophages/monocytes and neutrophils expressing interferon-, autoimmune-, and complement-related genes might contribute towards pro-fibrotic inflammatory lung responses following airborne biohazard exposures in setting of autoimmune arthritis and could be predictive and/or targeted to reduce disease burden.

RhoA as a Key Regulator of Innate and Adaptive Immunity

RhoA is a ubiquitously expressed cytoplasmic protein that belongs to the family of small GTPases. RhoA acts as a molecular switch that is activated in response to binding of chemokines, cytokines, and growth factors, and via mDia and the ROCK signaling cascade regulates the activation of cytoskeletal proteins, and other factors. This review aims to summarize our current knowledge on the role of RhoA as a general key regulator of immune cell differentiation and function. The contribution of RhoA for the primary functions of innate immune cell types, namely neutrophils, macrophages, and conventional dendritic cells (DC) to (i) get activated by pathogen-derived and endogenous danger signals, (ii) migrate to sites of infection and inflammation, and (iii) internalize pathogens has been fairly established. In activated DC, which constitute the most potent antigen-presenting cells of the immune system, RhoA is also important for the presentation of pathogen-derived antigen and the formation of an immunological synapse between DC and antigen-specific T cells as a prerequisite to induce adaptive T cell responses. In T cells and B cells as the effector cells of the adaptive immune system Rho signaling is pivotal for activation and migration. More recently, mutations of Rho and Rho-modulating factors have been identified to predispose for autoimmune diseases and as causative for hematopoietic malignancies.