Product Citations: 8

Aicardi-Goutières syndrome (AGS) is an autoinflammatory disease characterized by aberrant interferon (IFN)-α production. The major cause of morbidity in AGS is brain disease, yet the primary source and target of neurotoxic IFN-α remain unclear. Here, we demonstrated that the brain was the primary source of neurotoxic IFN-α in AGS and confirmed the neurotoxicity of intracerebral IFN-α using astrocyte-driven Ifna1 misexpression in mice. Using single-cell RNA sequencing, we demonstrated that intracerebral IFN-α-activated receptor (IFNAR) signaling within cerebral endothelial cells caused a distinctive cerebral small vessel disease similar to that observed in individuals with AGS. Magnetic resonance imaging (MRI) and single-molecule ELISA revealed that central and not peripheral IFN-α was the primary determinant of microvascular disease in humans. Ablation of endothelial Ifnar1 in mice rescued microvascular disease, stopped the development of diffuse brain disease, and prolonged lifespan. These results identify the cerebral microvasculature as a primary mediator of IFN-α neurotoxicity in AGS, representing an accessible target for therapeutic intervention.
Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.

  • Mus musculus (House mouse)
  • Immunology and Microbiology

Kinetic Characterization of the Immune Response to Methicillin-Resistant Staphylococcus aureus Subcutaneous Skin Infection.

In Infection and Immunity on 21 July 2022 by Ridder, M. J., McReynolds, A. K. G., et al.

Staphylococcus aureus is a leading cause of skin and soft tissue infections (SSTIs). Studies examining the immune response to S. aureus have been conducted, yet our understanding of the kinetic response to S. aureus subcutaneous skin infection remains incomplete. In this study, we used C57BL/6J mice and USA300 S. aureus to examine the host-pathogen interface from 8 h postinfection to 15 days postinfection (dpi), with the following outcomes measured: lesion size, bacterial titers, local cytokine and chemokine levels, phenotype of the responding leukocytes, and histopathology and Gram staining of skin tissue. Lesions were largest at 1 dpi, with peak necrotic tissue areas at 3 dpi, and were largely resolved by 15 dpi. During early infection, bacterial titers were high, neutrophils were the most abundant immune cell type, there was a decrease in most leukocyte populations found in uninfected skin, and many different cytokines were produced. Histopathological analysis demonstrated swift and extensive keratinocyte death and robust and persistent neutrophil infiltration. Gram staining revealed subdermal S. aureus colonization and, later, limited migration into upper skin layers. Interleukin-17A/F (IL-17A/F) was detected only starting at 5 dpi and coincided with an immediate decrease in bacterial numbers in the following days. After 9 days, neutrophils were no longer the most abundant immune cell type present as most other leukocyte subsets returned, and surface wounds resolved coincident with declining bacterial titers. Collectively, these data illustrate a dynamic immune response to S. aureus skin infection and suggest a key role for precisely timed IL-17 production for infection clearance and healthy tissue formation.

  • Mus musculus (House mouse)
  • Immunology and Microbiology

In situ transplantation of adipose-derived stem cells via photoactivation improves glucose metabolism in obese mice.

In Stem Cell Research & Therapy on 15 July 2021 by Zhu, L., Feng, Z., et al.

Accumulating evidence suggests that enhanced adipose tissue macrophages (ATMs) are associated with metabolic disorders in obesity and type 2 diabetes. However, therapeutic persistence and reduced homing stem cell function following cell delivery remains a critical hurdle for the clinical translation of stem cells in current approaches.
We demonstrate that the effect of a combined application of photoactivation and adipose-derived stem cells (ASCs) using transplantation into visceral epididymal adipose tissue (EAT) in obesity. Cultured ASCs were derived from subcutaneous white adipose tissue isolated from mice fed a normal diet (ND).
In diet-induced obesity, implantation of light-treated ASCs improved glucose tolerance and ameliorated systemic insulin resistance. Intriguingly, compared with non-light-treated ASCs, light-treated ASCs reduced monocyte infiltration and the levels of ATMs in EAT. Moreover, implantation of light-treated ASCs exerts more anti-inflammatory effects by suppressing M1 polarization and enhancing macrophage M2 polarization in EAT. Mass spectrometry revealed that light-treated human obese ASCs conditioned medium retained a more complete secretome with significant downregulation of pro-inflammatory cytokines and chemokines.
These data suggest that the combined application of photoactivation and ASCs using transplantation into dysfunctional adipose tissue contribute to selective suppression of inflammatory responses and protection from insulin resistance in obesity and type 2 diabetes.
© 2021. The Author(s).

  • FC/FACS
  • Mus musculus (House mouse)
  • Biochemistry and Molecular biology
  • Cell Biology
  • Stem Cells and Developmental Biology

Prolonged therapeutic effects of photoactivated adipose-derived stem cells following ischaemic injury.

In Acta Physiologica (Oxford, England) on 1 September 2020 by Fan, X., Li, K., et al.

Adipose-derived stem cells (ASCs) therapies are emerging as a promising approach to therapeutic angiogenesis. Therapeutic persistence and reduced primitive stem cell function following cell delivery remains a critical hurdle for the clinical translation of stem cells in current approaches.
Cultured ASCs were derived from subcutaneous white adipose tissue isolated from mice fed a normal diet (ND). Unilateral hindlimb ischaemia model was induced in high-fat diet (HFD)-fed mice by femoral artery interruption, after which photoactivated and non-light-treated ASCs were injected into the tail vein of mice. Laser Doppler imaging was conducted to measure the blood flow reperfusion. Capillary density was measured in the ischaemic gastrocnemius muscle. mRNA levels of angiogenic factors were determined by reverse-transcription polymerase chain reaction. Flow cytometry was used to determine the characterization of ASCs and endothelial progenitor cell (EPC). Human ASCs secretomes were analysed by liquid chromatography tandem mass spectrometry.
Our study demonstrated that photoactivated ND-ASCs prolonged functional blood flow perfusion and increased ASCs-derived EPC and neovascularization 38 days after ligation, when compared with saline-treated controls. Profiling analysis in ischaemic muscles showed upregulation of genes associated with pro-angiogenic factors after injection of photoactivated ND-ASCs when compared with the non-light-treated ASCs or saline treated HFD mice. Mass spectrometry revealed that light-treated ASCs conditioned medium retained a more complete pro-angiogenic activity with significant upregulation of angiogenesis related proteins.
Our data demonstrates that photoactivated ND-ASCs improve blood flow recovery and their injection may prove to be a useful strategy for the prevention and treatment of diabetic peripheral arterial disease.
© 2020 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  • FC/FACS
  • Mus musculus (House mouse)
  • Stem Cells and Developmental Biology

Appropriate balance of T helper 17 (Th17) and regulatory T (Treg) cells maintains immune tolerance and host defense. Disruption of Th17-Treg cell balance is implicated in a number of immune-mediated diseases, many of which display dysregulation of the insulin-like growth factor (IGF) system. Here, we show that, among effector T cell subsets, Th17 and Treg cells selectively expressed multiple components of the IGF system. Signaling through IGF receptor (IGF1R) activated the protein kinase B-mammalian target of rapamycin (AKT-mTOR) pathway, increased aerobic glycolysis, favored Th17 cell differentiation over that of Treg cells, and promoted a heightened pro-inflammatory gene expression signature. Group 3 innate lymphoid cells (ILC3s), but not ILC1s or ILC2s, were similarly responsive to IGF signaling. Mice with deficiency of IGF1R targeted to T cells failed to fully develop disease in the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis. Thus, the IGF system represents a previously unappreciated pathway by which type 3 immunity is modulated and immune-mediated pathogenesis controlled.
Copyright © 2020 Elsevier Inc. All rights reserved.

  • Mus musculus (House mouse)
  • Endocrinology and Physiology
  • Immunology and Microbiology
View this product on CiteAb