Upregulation of IL-4 receptor signaling pathway in circulating ILC2s from asthma patients

Combining metabolomics with network pharmacology to reveal the therapeutic mechanism of Dingchuan Decoction in rats with OVA-induced allergic asthma

Dingchuan Decoction (DCD) is a traditional Chinese medicine prescription commonly used in the treatment of asthma, but the mechanism of DCD in treating asthma has not yet been determined. In this study, we employed a combination of metabolomics and network pharmacology to investigate the mechanism of DCD in treating asthma. An allergic asthma rat model was induced by ovalbumin (OVA). Metabolomics based on 1H NMR and UHPLC-MS was used to identify differential metabolites and obtain the major metabolic pathways and potential targets. Network pharmacology was utilized to explore potential targets of DCD for asthma treatment. Finally, the results of metabolomics and network pharmacology were integrated to obtain the key targets and metabolic pathways of DCD for the therapy of asthma, and molecular docking was utilized to validate the key targets. A total of 76 important metabolites and 231 potential targets were identified through metabolomics. Using network pharmacology, 184 potential therapeutic targets were obtained. These 184 targets were overlaid with the 231 potential targets obtained through metabolomics and were analyzed in conjunction with metabolic pathways. Ultimately, the key targets were identified as aldehyde dehydrogenase 2 (ALDH2) and amine oxidase copper-containing 3 (AOC3), and the relevant metabolic pathways affected were glycolysis and gluconeogenesis as well as arginine and proline metabolism. Molecular docking showed that the key targets had high affinity with the relevant active ingredients in DCD, which further demonstrated that DCD may exert therapeutic effects by acting on the key targets. The present study demonstrated that DCD can alleviate OVA-induced allergic asthma and that DCD may have a therapeutic effect by regulating intestinal flora and polyamine metabolism through its effects on ALDH2 and AOC3.

Circulating innate lymphoid cells (cILCs): Unconventional lymphocytes with hidden talents

Innate lymphoid cells (ILCs) are a group of lymphocytes that are devoid of antigen-specific receptors and are mainly found in tissues. The subtypes ILC1, 2, and 3 mirror T-cell functionality in terms of cytokine production and expression of key transcription factors. Although the majority of ILCs are found in tissue (tILCs), they have also been described within the circulation (cILCs). As a result of their better accessibility and putative prognostic value, human cILCs are getting more and more attention in clinical research. However, cILCs are in many aspects functionally distinct from their tILC counterparts. In fact, from the 3 ILC subsets found within the circulation, only for cILC2s could a clear functional correspondence to their tissue counterparts be established. Indeed, cILC2s are emerging as a major driver of allergic reactions with a particular role in asthma. In contrast, recent studies revealed that cILC1s and cILC3s are predominantly in an immature state and constitute progenitors for natural killer cells and ILCs, respectively. We provide an overview about the phenotype and function of the different cILC subtypes compared to tILCs in health and disease, including transcriptomic signatures, frequency dynamics, and potential clinical value. Furthermore, we will highlight the dynamics of the NKp44+ ILC3 subset, which emerges as prognostic marker in peripheral blood for inflammatory bowel disease and leukemia.

Single cell multi-omic analysis identifies key genes differentially expressed in innate lymphoid cells from COVID-19 patients

Introduction

Innate lymphoid cells (ILCs) are enriched at mucosal surfaces where they respond rapidly to environmental stimuli and contribute to both tissue inflammation and healing.

Methods

To gain insight into the role of ILCs in the pathology and recovery from COVID-19 infection, we employed a multi-omics approach consisting of Abseq and targeted mRNA sequencing to respectively probe the surface marker expression, transcriptional profile and heterogeneity of ILCs in peripheral blood of patients with COVID-19 compared with healthy controls.

Results

We found that the frequency of ILC1 and ILC2 cells was significantly increased in COVID-19 patients. Moreover, all ILC subsets displayed a significantly higher frequency of CD69-expressing cells, indicating a heightened state of activation. ILC2s from COVID-19 patients had the highest number of significantly differentially expressed (DE) genes. The most notable genes DE in COVID-19 vs healthy participants included a) genes associated with responses to virus infections and b) genes that support ILC self-proliferation, activation and homeostasis. In addition, differential gene regulatory network analysis revealed ILC-specific regulons and their interactions driving the differential gene expression in each ILC.

Discussion

Overall, this study provides mechanistic insights into the characteristics of ILC subsets activated during COVID-19 infection.

Preliminary study of identified novel susceptibility loci for HAPE risk in a Chinese male Han population

High altitude pulmonary edema (HAPE) is a life-threatening form of non-cardiogenic pulmonary edema. In recent years, association studies have become the main method for identifying HAPE genetic loci. A genome-wide association study (GWAS) of HAPE risk-associated loci was performed in Chinese male Han individuals (164 HAPE cases and 189 healthy controls) by the Precision Medicine Diversity Array Chip with 2,771,835 loci (Applied Biosystems Axiom™). Eight overlapping candidate loci in CCNG2, RP11-445O3.2, NUPL1 and WWOX were finally selected. In silico functional analyses displayed the PPI network, functional enrichment and signal pathways related to CCNG2, NUPL1, WWOX and NRXN1. This study provides data supplements for HAPE susceptibility gene loci and new insights into HAPE susceptibility.

Time-dependent cell-state selection identifies transiently expressed genes regulating ILC2 activation

The decision of whether cells are activated or not is controlled through dynamic intracellular molecular networks. However, the low population of cells during the transition state of activation renders the analysis of the transcriptome of this state technically challenging. To address this issue, we have developed the Time-Dependent Cell-State Selection (TDCSS) technique, which employs live-cell imaging of secretion activity to detect an index of the transition state, followed by the simultaneous recovery of indexed cells for subsequent transcriptome analysis. In this study, we used the TDCSS technique to investigate the transition state of group 2 innate lymphoid cells (ILC2s) activation, which is indexed by the onset of interleukin (IL)-13 secretion. The TDCSS approach allowed us to identify time-dependent genes, including transiently induced genes (TIGs). Our findings of IL4 and MIR155HG as TIGs have shown a regulatory function in ILC2s activation.