Chronic allergy signaling: is it all stressed-out mitochondria?

Allergic diseases in general, and chronic allergic inflammation in particular, are on the rise in the United States and other developed countries. The idea of chronic allergic disease as a chronic type 2 immune response has been around for several decades. However, data suggest that other mechanisms may be important in chronic disease.

Low-Dose Lipopolysaccharide Protects from Lethal Paramyxovirus Infection in a Macrophage- and TLR4-Dependent Process.

Respiratory diseases are a major public health burden and a leading cause of death and disability in the world. Understanding antiviral immune responses is crucial to alleviate morbidity and mortality associated with these respiratory viral infections. Previous data from human and animal studies suggested that pre-existing atopy may provide some protection against severe disease from a respiratory viral infection.

Mouse Model of Sendai Virus-Induced Lung Disease.

Sendai virus (SeV), also known as the murine parainfluenza virus 1, is an enveloped negative-sense RNA paramyxovirus from the family Paramyxoviridae and genus Respirovirus. The virus was named after Sendai, city in Japan, where it was first isolated (Kuroya, Ishida, Yokohama Med Bull 4:217-233, 1953). Antigenically, SeV is closely related to human parainfluenza viruses 1 and 3.

Atopic Neutrophils Prevent Postviral Airway Disease.

Respiratory syncytial virus (RSV) infection in infancy is associated with increased risk of asthma, except in those with allergic disease at the time of infection. Using house dust mite allergen, we examined the effect of pre-existing atopy on postviral airway disease using Sendai virus in mice, which models RSV infection in humans. Sendai virus drives postviral airway disease in nonatopic mice; however, pre-existing atopy protected against the development of airway disease.

Adapting CRISPR/Cas9 System for Targeting Mitochondrial Genome.

Gene editing of the mitochondrial genome using the CRISPR-Cas9 system is highly challenging mainly due to sub-efficient delivery of guide RNA and Cas9 enzyme complexes into the mitochondria. In this study, we were able to perform gene editing in the mitochondrial DNA by appending an NADH-ubiquinone oxidoreductase chain 4 (ND4) targeting guide RNA to an RNA transport-derived stem loop element (RP-loop) and expressing the Cas9 enzyme with a preceding mitochondrial localization sequence. We observe mitochondrial colocalization of RP-loop gRNA and a marked reduction of ND4 expression in the cells carrying a 11205G variant in their ND4 sequence coincidently decreasing the mtDNA levels.

Post-viral atopic airway disease: pathogenesis and potential avenues for intervention.

: In early childhood, wheezing due to lower respiratory tract illness is often associated with infection by commonly known respiratory viruses such as respiratory syncytial virus (RSV) and human rhinovirus (RV). How respiratory viral infections lead to wheeze and/or asthma is an area of active research. : This review provides an updated summary of the published information on the development of post-viral induced atopy and asthma and the mechanisms involved.

Intestinal Microbiota Disruption Reduces Regulatory T Cells and Increases Respiratory Viral Infection Mortality Through Increased IFNγ Production.

Alterations in gastrointestinal microbiota indirectly modulate the risk of atopic disease, but effects on respiratory viral infections are less clear. Using the murine paramyxoviral virus type 1, Sendai virus (SeV), we examined the effect of altering gastrointestinal microbiota on the pulmonary antiviral immune response. C57BL6 mice were treated with streptomycin before or during infection with SeV and resulting immune response studied.

Generation of Knock-out Primary and Expanded Human NK Cells Using Cas9 Ribonucleoproteins.

CRISPR/Cas9 technology is accelerating genome engineering in many cell types, but so far, gene delivery and stable gene modification have been challenging in primary NK cells. For example, transgene delivery using lentiviral or retroviral transduction resulted in a limited yield of genetically-engineered NK cells due to substantial procedure-associated NK cell apoptosis. We describe here a DNA-free method for genome editing of human primary and expanded NK cells using Cas9 ribonucleoprotein complexes (Cas9/RNPs).

Cysteinyl leukotriene receptor 1 expression identifies a subset of neutrophils during the antiviral response that contributes to postviral atopic airway disease.

Background: Viral respiratory tract infections increase the risk of development and exacerbation of atopic disease. Previously, we demonstrated the requirement for a neutrophil (PMN) subset expressing CD49d to drive development of postviral atopic airway disease in mice.

Objective: We sought to determine whether human CD49d PMNs are present in the nasal mucosa during acute viral respiratory tract infections and further characterize this PMN subset in human subjects and mice.

Impaired regeneration in calpain-3 null muscle is associated with perturbations in mTORC1 signaling and defective mitochondrial biogenesis.

Background: Previous studies in patients with limb-girdle muscular dystrophy type 2A (LGMD2A) have suggested that calpain-3 (CAPN3) mutations result in aberrant regeneration in muscle.

Methods: To gain insight into pathogenesis of aberrant muscle regeneration in LGMD2A, we used a paradigm of cardiotoxin (CTX)-induced cycles of muscle necrosis and regeneration in the CAPN3-KO mice to simulate the early features of the dystrophic process in LGMD2A. The temporal evolution of the regeneration process was followed by assessing the oxidative state, size, and the number of metabolic fiber types at 4 and 12 weeks after last CTX injection.

VIP-expressing dendritic cells protect against spontaneous autoimmune peripheral polyneuropathy.

The spontaneous autoimmune peripheral polyneuropathy (SAPP) model in B7-2 knockout nonobese diabetic mice mimics a progressive and unremitting course of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). In this study, bone marrow-derived dendritic cells (DCs) were transduced to express vasoactive intestinal polypeptide (VIP) using a lentiviral vector (LV-VIP). These transduced DCs (LV-VIP-DCs) were then injected intravenously (i.

Hypoxia inducible microRNA 210 attenuates keratinocyte proliferation and impairs closure in a murine model of ischemic wounds.

Ischemia complicates wound closure. Here, we are unique in presenting a murine ischemic wound model that is based on bipedicle flap approach. Using this model of ischemic wounds we have sought to elucidate how microRNAs may be implicated in limiting wound re-epithelialization under hypoxia, a major component of ischemia.

MicroRNA expression in response to murine myocardial infarction: miR-21 regulates fibroblast metalloprotease-2 via phosphatase and tensin homologue.

Aims: MicroRNAs (miRNAs) are small non-coding RNAs that regulate gene expression at the post-transcriptional level by either degradation or translational repression of a target mRNA. Encoded in the genome of most eukaryotes, miRNAs have been proposed to regulate specifically up to 90% of human genes through a process known as miRNA-guided RNA silencing. For the first time, we sought to test how myocardial ischaemia-reperfusion (IR) changes miR expression.

Flavopiridol causes early mitochondrial damage in chronic lymphocytic leukemia cells with impaired oxygen consumption and mobilization of intracellular calcium.

Effective administration of flavopiridol in advanced-stage chronic lymphocytic leukemia (CLL) is often associated with early biochemical evidence of tumor cell lysis. Previous work using other cell types showed that flavopiridol impacts mitochondria, and in CLL cells flavopiridol down-regulates the mitochondrial protein Mcl-1. We therefore investigated mitochondrial structure and function in flavopiridol-treated CLL patient cells and in the lymphoblastic cell line 697 using concentrations and times at which tumor lysis is observed in treated patients.

IL-21 mediates apoptosis through up-regulation of the BH3 family member BIM and enhances both direct and antibody-dependent cellular cytotoxicity in primary chronic lymphocytic leukemia cells in vitro.

Interleukin-21 (IL-21) is a recently identified gamma-chain receptor cytokine family member that promotes B-cell apoptosis as well as activation of innate immune system. Based on this, we hypothesized that IL-21 might enhance the apoptosis induced by fludarabine and rituximab and also play a role in augmenting immune-mediated clearance of the chronic lymphocytic leukemia (CLL) cells. Our studies demonstrate that the majority of CLL patients have surface IL-21 receptor-alpha, and its expression correlates with apoptosis, tyrosine phosphorylation of STAT1, and up-regulation of the proapoptotic BH3 domain protein BIM.

Mcl-1 is a relevant therapeutic target in acute and chronic lymphoid malignancies: down-regulation enhances rituximab-mediated apoptosis and complement-dependent cytotoxicity.

Purpose: The antiapoptotic Bcl-2 family member protein Mcl-1 is dynamically regulated in transformed B-cells, has a short mRNA and protein half-life, and is rapidly processed during apoptosis. Multiple therapies cause down-regulation of Mcl-1 in chronic and acute lymphoid leukemia (CLL and ALL) cells. Mcl-1 has also been reported to mediate resistance to rituximab in CLL.

Reciprocal regulation of nuclear factor kappa B and its inhibitor ZAS3 after peripheral nerve injury.

Background: NF-kappaB binds to the kappaB motif to regulate transcription of genes involved in growth, immunity and inflammation, and plays a pivotal role in the production of pro-inflammatory cytokines after nerve injuries. The zinc finger protein ZAS3 also binds to the kappaB or similar motif. In addition to competition for common DNA sites, in vitro experiments have shown that ZAS3 can inhibit NF-kappaB via the association with TRAF2 to inhibit the nuclear translocation of NF-kappaB.

Anti-fibroblast growth factor-2 antibodies attenuate mechanical allodynia in a rat model of neuropathic pain.

Peripheral nerve injury leads to the activation of spinal cord astrocytes, which contribute to maintaining neuropathic (NP) pain behavior. Fibroblast growth factor-2 (FGF-2), a neurotrophic and gliogenic factor, is upregulated by spinal cord astrocytes in response to ligation of spinal nerves L5 and L6 (spinal nerve ligation [SpNL]). To evaluate the contribution of spinal astroglial FGF-2 to mechanical allodynia following SpNL, neutralizing antibodies to FGF-2 were injected intrathecally.

Proteomic identification of brainstem cytosolic proteins in a neuropathic pain model.

Neuropathic pain involves co-regulation of many genes and their translational products in both peripheral and central nervous system. We used proteomics approaches to investigate expressional changes in cytosolic protein levels in rat brainstem tissues following ligation of lumbar 5 and 6 (L5, L6) spinal nerves, which generates a model of peripheral neuropathic pain (NP). Proteins from brainstem tissue homogenates of NP and SHAM animals were fractionated by two-dimensional (2-DE) gel electrophoresis to produce a high-resolution map of the brainstem soluble proteins.

Differential change in mRNA expression of p75 and Trk neurotrophin receptors in nucleus gracilis after spinal nerve ligation in the rat.

In peripheral neuropathy (PN), dorsal column (DC) fibers that synapse in the nucleus gracilis (NuGr) mediate expression of mechanical allodynia and have increased expression of brain-derived neurotrophic factor (BDNF). Neurotrophins (NTs) are implicated in pathology or repair in PN. To assess NTs in the NuGr in PN, mRNA expression of BDNF, nerve growth factor (NGF), and NT receptors TrkA, TrkB, and p75 was determined 1 week after ligation of L5 and L6 spinal nerves (SNL).

Upregulation of FGF-2 in reactive spinal cord astrocytes following unilateral lumbar spinal nerve ligation.

Spinal nerve ligation results in dramatic changes in spinal cord primary C-afferent fibers, which include atrophy with an accompanied decrease in calcitonin-gene-related peptide (CGRP). These changes parallel the activation of astrocytes, which have been implicated in the ensuing neuropathic pain states. As part of an effort to elucidate the role of the downstream effectors of astrocyte reactivity in the context of allodynia, the expression of fibroblast growth factor-2 (FGF-2) was examined following tight ligation of L5 and L6 spinal nerves.