GAB2 regulates type 2 T helper cell differentiation in humans

The immunological mechanisms and therapeutic potential in drug-induced liver injury: lessons learned from acetaminophen hepatotoxicity

Acute liver failure caused by drug overdose is a significant clinical problem in developed countries. Acetaminophen (APAP), a widely used analgesic and antipyretic drug, but its overdose can cause acute liver failure. In addition to APAP-induced direct hepatotoxicity, the intracellular signaling mechanisms of APAP-induced liver injury (AILI) including metabolic activation, mitochondrial oxidant stress and proinflammatory response further affect progression and severity of AILI. Liver inflammation is a result of multiple interactions of cell death molecules, immune cell-derived cytokines and chemokines, as well as damaged cell-released signals which orchestrate hepatic immune cell infiltration. The immunoregulatory interplay of these inflammatory mediators and switching of immune responses during AILI lead to different fate of liver pathology. Thus, better understanding the complex interplay of immune cell subsets in experimental models and defining their functional involvement in disease progression are essential to identify novel therapeutic targets for the treatment of AILI. Here, this present review aims to systematically elaborate on the underlying immunological mechanisms of AILI, its relevance to immune cells and their effector molecules, and briefly discuss great therapeutic potential based on inflammatory mediators.

A game changer for bipolar disorder diagnosis using RNA editing-based biomarkers

In clinical practice, differentiating Bipolar Disorder (BD) from unipolar depression is a challenge due to the depressive symptoms, which are the core presentations of both disorders. This misdiagnosis during depressive episodes results in a delay in proper treatment and a poor management of their condition. In a first step, using A-to-I RNA editome analysis, we discovered 646 variants (366 genes) differentially edited between depressed patients and healthy volunteers in a discovery cohort of 57 participants. After using stringent criteria and biological pathway analysis, candidate biomarkers from 8 genes were singled out and tested in a validation cohort of 410 participants. Combining the selected biomarkers with a machine learning approach achieved to discriminate depressed patients (n = 267) versus controls (n = 143) with an AUC of 0.930 (CI 95% [0.879-0.982]), a sensitivity of 84.0% and a specificity of 87.1%. In a second step by selecting among the depressed patients those with unipolar depression (n = 160) or BD (n = 95), we identified a combination of 6 biomarkers which allowed a differential diagnosis of bipolar disorder with an AUC of 0.935 and high specificity (Sp = 84.6%) and sensitivity (Se = 90.9%). The association of RNA editing variants modifications with depression subtypes and the use of artificial intelligence allowed developing a new tool to identify, among depressed patients, those suffering from BD. This test will help to reduce the misdiagnosis delay of bipolar patients, leading to an earlier implementation of a proper treatment.

Analysis of the microRNA and mRNA expression profile of ricin toxin-treated RAW264.7 cells reveals that miR-155-3p suppresses cell inflammation by targeting GAB2

Ricin toxin (RT) is one of the most lethal toxins derived from the seed of castor beans. In addition to its main toxic mechanism of inhibiting the synthesis of cellular proteins, RT can induce the production of inflammatory cytokines. MicroRNAs (miRNAs) play a key role in regulating both innate and adaptive immunity. To elucidate the regulation of miRNAs in RT-induced inflammation injury, the RNA high-throughput sequencing (RNA-Seq) technology was used to analyze the expression profile of miRNAs and mRNAs in RT-treated RAW264.7 cells. Results showed that a total of 323 mRNAs and 19 miRNAs differentially expressed after RT treated. Meanwhile, 713 miRNA-mRNA interaction pairs were identified by bioinformatics analysis. KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis showed that those interaction pairs were mainly involved in JAK-STAT, T cell receptor, and MAPK signaling pathways. Moreover, we further predicted and determined the targeting relationship between miR-155-3p and GAB2 through TargetScan and dual-luciferase reporter assay. Mechanically, overexpression of miR-155-3p can reduce the secretion of TNF-α in RAW264.7 cells, revealing a possible mechanism of miR-155-3p regulating RT-induced inflammatory injury. This study provides a new perspective for clarifying the mechanism of RT-induced inflammatory injury and reveals the potential role of miRNAs in innate immune regulation.